solutions for dust on dirt roads - nivitex · ‘**** treton impact value the formation of typical...
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Solutions for Dust on Dirt Roads
DS-11-LB(Dust Suppressant 11 Lignin Base)
LIMIT OF LIABILITY APPLIES
The information included in this document is given in good faith and is intended to assist you the customer in determining the suitability of this product for your application. Due to the diverse applications and conditions in which many of our products may be used, we request that you, the user, test and inspect our product to satisfy yourself of its contents and suitability for your specific need. This document does not constitute any guarantee or warranty expressed or implied. The exclusive remedy for all proven claims is replacement of our product and under no circumstances shall we be liable for any special, consequential or incidental damages.
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
Solutions for dust on mining haul roads
Dust on Mining Haul RoadsRoads on mines are often constructed in locations that are problematic, using materials that are far from ideal. This applies equally to haul and access roads, whether they are above or below ground. The problem is exacerbated by the inordinately heavy use that characterizes mining operations.
Dust emissions affect visibility and are a cause of accidents, increased wear and tear on vehicles and resultant maintenance costs. Roads that are not adequately stabilised require additional maintenance and replacement of gravel, resulting in lost time and additional costs.
OHS, mining and environmental regulations require that dust emissions be controlled. Currently water is widely used for this purpose. This approach is both expensive and inefficient. These factors as well as the reduced availability of water as a result of climate change mandate an alternative solution.
Using DS-11-LB Dust Suppressant will:
Improve visibility and road safety•
Provide a hard, smooth dust free surface•
Reduce road water usage by up to 90%•
Reduce gravel loss and increase the load-bearing • capacity of existing road materials
Reduce vehicle operating and maintenance costs•
Minimise road maintenance costs•
Lower road maintenance equipment requirement•
Ensure cost effective, high performance dust control•
Reduce water run-off and furrowing•
AdvantagesOptimised health and safety standards•
Enhance environmental compliance•
Increase financial performance•
Use less fuel•
Reduce Carbon Footprint•
Reduce man-hours•
DS-11-LB Dust Suppressant• is a green product
Non toxic, renewable and environmentally friendly•
The ProductDS-11-LB Dust Suppressant is a product derived from the pulp wood industry. It is non-toxic to humans, fauna and flora and is used in diverse products for the food industry, agriculture, construction and mining. It is biodegradable and made from entirely renewable sources. It works by bonding road base particles together and thereby reduces the need for the use of water and other aggregates.
DS-11-LB Dust Suppressant is easy to use, does not require the use of specialised application equipment and can either be incorporated during road construction or applied to formed road surfaces.
DS-11-LB Dust Suppressant is a green renewable cost effective solution to dust problems.
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
How to use DS-11-LB Dust Suppressant?DS-11-LB Dust Suppressant is not material specific and performs effectively on a wide range of road base materials. It is however important to note that the road to be stabilised should be constructed to recognised standards and built using appropriate materials. These factors will determine the volume of DS-11-LB Dust Suppressant to be applied and contribute significantly to the overall efficacy of the stabilisation, Application rates and methods are adapted to particular situations. In some cases soil tests will need to be performed.
Material selection guidelines for unsealed roads:
‘* Linear shrinkage x % passing on 0.425mm sieve
‘** (% passing 26.5mm - % passing 2.0mm) x % passing 4.75mm/100
‘*** California bearing ratio – soaked at > 95% Mod AASHTO
‘**** Treton impact value
The formation of typical defects such as corrugations, erosion, potholes, ravelling and slipperiness is related to the use of inappropriate materials or poor construction and maintenance practices. The predicted performance of non-conforming materials is illustrated in the figure to the right.
Surface Haul RoadsThe performance-related material selection guidelines in figure 1 is recommended for DS-11-LB Dust Suppressant applications, where high riding quality, year-round access and low maintenance are required. The application rate of DS-11-LB Dust Suppressant is determined by the soils mechanical properties rather than by soil chemistry. DS-11-LB Dust Suppressant can be applied either to formed roads by an over the top application or incorporated to road base during construction.
DS-11-LB Dust Suppressant can be used to eliminate dust problems on unpaved roads, finely divided coal and mineral ores. DS-11-LB Dust Suppressant has exceptional soil stabilisation properties enhancing the appearance of the road, improving safety standards and providing a cost effective solution to dust and road surface deterioration.
Underground Haul RoadsThe guideline for underground haul roads is less stringent since these roads are generally unaffected by climatic factors (rainfall, and temperature / humidity fluctuations) and are usually level and supported by bedrock. The spray on method allows the treatment of vital transport arteries and detours without tying up traffic. DS-11-LB Dust Suppressant reduces dust emissions by binding dust particles together, producing a firmly bound surface that adds traction, increases water runoff and reduces mud conditions.
Economic AnalysisThe table below, produced from road performance prediction models, indicates savings achieved under diverse circumstances using DS-11-LB Dust Suppressant:
Significant cost reductions are also achieved in relation to vehicle operating, maintenance and lower equipment requirements.
”Research shows that unpaved roads treated with calcium lignosulphonate retained 42–61% more aggregate than the untreated test section. The cost savings of retaining aggregate on the treated test sections more than offset the costs of the dust suppressants, resulting in an estimated cost savings of 28–42% over the untreated control test section.”
(Effectiveness and Environmental Impact of Road Dust Suppressants by Thomas G. Saunders, PhD and Jonathan Q. Addo. Department of Civil Engineering, Colorado State University .December 1993)
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
Key Elements to Product ApplicationDS-11-LB Dust Suppressant • can be applied either
as a spray-on or incorporated application.
The three key issues are dosage, speed of application • and product concentration.
In order to achieve penetration of the road surface a • pre-watering with approximately 1 to 1.5L/m² is required.
Aim to wet to a depth of 150mm.•
Calculate the concentration of • DS-11-LB Dust Suppressant to be used in relation to the absorption rate, in order to maximize penetration and prevent surface run-off.
DS-11-LB Dust Suppressant • can be applied with available equipment – no specialised equipment is required.
Ensure that • DS-11-LB Dust Suppressant is evenly applied across the entire surface (avoid irregular application on the middle or sides).
The road must be shaped to allow for water run-off • and prevent pooling.
Compact the surface with a smooth roller for an • optimum surface finish.
For incorporated applications, rip the road to 150mm breaking large clods to maximum 50 mm in diameter. Calculate the approximate volume of water required to reach optimum moisture content and add two-thirds of the product to be applied. Apply the solution to the prepared road surface in 4 to 6 applications, mixing the road base thoroughly between applications. Shape the surface to the required camber in order to allow for proper drainage. Compact the road with a roller to required density. The one third remaining product should be sprayed onto the finished compacted surface while still damp. The road maybe used immediately after treatment.
Dust SuppressionDS-11-LB Dust Suppressant is very effective in suppressing dust in low volume traffic areas, such as road verges, lay down areas, car parks etc.. It is applied as a spray on in a single application with a dilution of approximately 10:1 and aims to achieve 0.2 litres of DS-11-LB Dust Suppressant m²
MaintenanceReapplication may be necessitated due to a lack of moisture during the dry season or after heavy, sustained bouts of rain. In order to keep the surface dust free it is essential to implement a planned road maintenance programme along with a DS-11-LB Dust Suppressant rejuvenation schedule. The volume of DS-11-LB Dust Suppressant to be applied and frequency of maintenance will depend on the material characteristics, application method, climate and traffic density and speed.
Other factors influencing reapplication frequency are payload spillage, debris and fugitive dust blown onto the road surface. Rejuvenation should be carried out before significant deterioration has occurred. Rejuvenation should be done using between 0.08 litres of DS-11-LB Dust Suppressant per square metre of area. This may vary considerably and should therefore be assessed by a DS-11-LB Dust Suppressant representative.
Road StabilisationDS-11-LB Dust Suppressant is very effective in stabilising and binding gravel roads. It can be applied as either a spray on or an incorporated application.
Spray-on or over the top applications of DS-11-LB Dust Suppressant are most common as haul roads cannot normally be decommissioned to allow incorporated applications. The road surface should be well compacted to a density greater than 93%, firm and free of excess loose material and with sufficient camber to allow proper drainage. Ensure the surface is watered before each application.
The product should be used in multiple applications using a 10% solution of product with water avoiding run-off and pooling. The road maybe used immediately after treatment. Incorporated applications are used to bind and stabilise a base layer with a thickness between 50 and 200 mm, eliminating individual particle movement. The product is incorporated into the road base during the water binding process. Conventional road making equipment is used.
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
How Does DS-11-LB Dust Suppressant Work?
Assists with dispersing smaller particles - aids • distribution during compacting, reducing the soil pore volume.
Enables less water to be used for optimal compaction • – as with concrete plasticising effect.
DS-11-LB Dust Suppressant• coats the particles.
On drying, any contacting particles stick together • because of the DS-11-LB Dust Suppressant coating the surfaces.
Best performance is achieved at the highest • compaction.
Benefits of Using DS-11-LB Dust Suppressant
Environmentally friendly.•
Suppresses unwanted road dust (better visibility/safer • driving conditions)
Provides hard, smooth, dust free roads and surfaces.•
Ensures excellent traction in wet and dry conditions.•
Significantly reduces vehicle wear and road • maintenance costs.
Significant water savings through operational life • of roads.
Simple, user-friendly application method.•
Use of existing equipment.•
Significant reduction of P.I. in material.•
Dramatic improvement in CBR of treated wearing • course.
Application Rates – Geology, Soil Types
DS-11-LB Dust Suppressant• is compatible with all aggregates, as tests with CSIR has proved.
Best results achieved where materials with sufficient • Grading Modulus (GM) are used.
Approximate Dilution GuidelinesClay – 10% for easy penetration•
Normal aggregate - 15%•
Soil sand – 20%•
Very porous material – use a thicker solution • for penetration
APPLICATION MANUALVery dense material – more diluted solution •
for penetration
Soil CompactionWhen constructing a road, proper compaction is of cardinal importance to obtain maximum performance and life expectancy. Determining the OMC (Optimum Moisture Content) for the particular soil geology will be required to then work out the compaction ratio or CBR (California Bearing Ratio) that will yield the best performances for the materials available. Site conditions will vary and each needs to have an assessment done to determine the appropriate course of action.
Mix in application of DS-11-LB Dust Suppressant during road construction has proven to be effective and assisting with the quality of the road once completed. Once the top layer has been properly compacted, the application of DS-11-LB Dust Suppressant will assist in reducing the loss of quarry material under traffic due to dust generation. Quarry material is a non-renewable resource and will become harder and more expensive to obtain due to haul distances to borrow pits to reconstruct the road surface once it has deteriorated.
Road PreparationThe preparation of the road is also dependant on site conditions. Marshy areas require drainage works and stabilisation where as sandy soils require addition of graded aggregate for building a stable base or sub grade layer. Top soil and vegetation has to be stripped off to reveal a more stable platform to construct the road on. The importation of quarry material from an approved borrow pit is an expensive operation.
DS-11-LB Dust Suppressant allows for the use of local/on-site materials, achieving similar/better results through chemically improving the CBR of materials used. The maintenance of the road once constructed is critical to extend the service life to the maximum. If the application is to be done on a road already constructed, the surface needs to be hard-packed by compaction and grading and must have as little residual dust before spraying as possible to assist in DS-11-LB Dust Suppressant penetrating the surface.
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
DS-11-LB Dust Suppressant Properties and DilutionThe initial and subsequent rejuvenation applications of DS-11-LB Dust Suppressant are generally accomplished by spraying a solution of the powder and water onto the surface being treated. As the percentage of solid matter
in solution affects the viscosity or “thickness” of the solution, it is necessary to dilute the liquid DS-11-LB Dust Suppressant to approximately 10-30% solids.
This is necessary, as penetration into the soil particles is affected by the “thickness” of the solution and logically, the finer the particles, the more difficult penetration becomes. The converse is true for coarsely graded soils where a higher solids content application can be used.
DS-11-LB Dust Suppressant can be used as either:
A powder supplied in bags.•
A solution delivered by road tanker.•
To explain the terminology of solids in solutions it is necessary to understand that the specific gravity of a solution increases as the solids content is raised. Water has an SG of 1 and therefore a litre of water weighs 1 kilogram. A DS-11-LB Dust Suppressant solution of 50-53% solids is the maximum effective dilution as the viscosity or “thickness” would increase handling problems such as pump ability. Therefore the liquid version is supplied at 50-53% solid content which is the optimum in terms of transport costs. This liquid DS-11-LB Dust Suppressant has an SG of 1.267 which implies that a litre would weigh 1.267 kilograms.
To explain the effect the Specific gravity has on the product application, it should be considered that DS-11-LB Dust Suppressant liquid at 53% solids is 1.267 times as heavy as water. Therefore the recommended dosage of 1 litre per square meter, the solids equivalent is 1.267 x 0.53 (% solids divided by 100) = 0.67 kg per m2.
Logically, the application rate in lt/m2 will increase as the product is diluted with water but still yield the mass of solids as recommended. Assuming a dilution of 20% solids, the equation would be 1.267 x 0.20 = 0.25kg solids per m2. If the original factor of 0.67 is then divided by the 0.25kg of solids, this will equal = 2.68 lt/m2. The SG describes the “thickness” or viscosity of the product and obviously affects the penetration of the liquid into the soil. If the substrate is of a clay nature (fine compacted silt) the penetration will be minimal with a “thick” or viscous solution and therefore needs to be diluted with water. The converse is true for sandy or loosely packed soil where a “thicker” or more viscous solution is required. This is largely based on experience or pre application trials. An added note which requires mention is the fact that 20-
53% solutions increase in viscosity under low temperature conditions and might require further dilution during the winter months.
Obviously, on site facilities would preclude exact measurement of water and DS-11-LB Dust Suppressant and should therefore be interpolated for convenient measurement.
Considerations When Selecting The Application Method
The availability of the equipment – if only limited • equipment is available, spray-on may be most suitable.
The need for on-going use of the road – it is essential • that the road remains in operation, spray-on is recommended.
The ease of penetration of • DS-11-LB Dust Suppressant solutions – if penetration of water is difficult, mix-in is recommended.
The length of time the application has to last•
If the requirement is for a short duration – spray-on • is recommended.
If the requirement is for a long period – mix-in or • spray-on, with rejuvenation, is applicable.
Rejuvenation is a must but only add back what • is required!
ApplicationsDS-11-LB Dust Suppressant Spray-on Application
DS-11-LB Dust Suppressant• is sprayed onto the road surface
Instant dust suppressant•
Uses less • DS-11-LB Dust Suppressant than the Mix-In method
A less costly application method•
Rejuvenation is done on a site specific bases or • when required
Massively reduces water requirement•
Road remains open – little/no disruption to • production/traffic.
Immediate improvement in road safety•
Depth of DS-11-LB Dust Suppressant penetration in Clay Soils
Depth of DS-11-LB Dust Suppressant penetration in Sandy Soils
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
Equipment Required For Spray-On Application: Water Cart or Water TankerDS-11-LB Dust Suppressant Liquid Application Method
(to be presented by a DS-11-LB Dust Suppressant consultant)
Check the compaction of the road, is the road in good • condition, if so, a spray on application is an option.
Check the way the water penetrates the road surface•
Use this check as a measure of the quantity of liquid • to apply per m2.
As an overview consider the amount of water to be • added relative to the OMC (Optimum Moisture Content) for compaction, including the moisture in the road, avoid mud.
Remember • DS-11-LB Dust Suppressant reduces the water demand.
If penetration is good – use a solution of higher solids • content, quicker application.
IF penetration is poor – use a more dilute solution • with more repetitions to try to get the surface penetration required for good results.
The total inclusion mass of • DS-11-LB Dust Suppressant solids is then delivered through multiple applications.
Pre-wet or apply after light rain to get better • penetration.
Apply water in between application to help • DS-11-LB Dust Suppressant penetrate.
Avoid run-off at the time of application – • wasteful of product.
Application can be made while the road is being used • as vehicles assist in compaction – providing there is no mud, else road camber and surface shape be comes distorted.
Ensure the road surface is firm, free of excess loose • material and with sufficient shape to ensure proper drainage.
Apply the product in multiple applications using the • prescribed dilution ratio.
After the initial application use the rejuvenation coats, • re-applying as required to suppress dust to the required level.
Mix-In Application (150mm)DS-11-LB Dust Suppressant• is mixed into the road
surface.
Longer lasting, deeper inclusion in road.•
More • DS-11-LB Dust Suppressant is required.
Rejuvenation is required using post Mix-in surface • sprays.
Equipment required mix –in application: Water cart or • water tanker, grader, compactor.
DS-11-LB Dust Suppressant Liquid Mix-In Application Method
The road is in a bad condition•
Wet the road surface•
Rip open surface to between 100-150 mm using • a grader.
Large clods to be broken to ensure sufficient • Grading Modulus (GM)
Add between 80-90% of the • DS-11-LB Dust Suppressant in the water calculated to bring the material to its OMC for compaction.
Remember to take into account the moisture in the • road and that DS-11-LB Dust Suppressant reduces the OMC by 3-5% - avoid mud.
Use a grader to accomplish mixing using windrows • and a water tanker.
Shape the road with a grader – considering levels and • drainage and shape.
Roll with smooth, steel roller or pneumatic tyre roller – • avoid vibrating ones as they can weaken the adhesion.
Compact to >93% Mod. AASHTO with multiple • passed of the roller.
Compact at the OMC for compaction – don’t delay on • hot days.
Re-open the road to traffic.•
Spray on remaining 10-20% of the • DS-11-LB Dust Suppressant on the surface.
To maintain, spray every +/- 2 weeks to a month, • depending on road material, climate conditions, traffic type/volume, etc.
Liquid dosage recommendation: 2 litres per m2 • (diluted mixture)
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
Example
Road measurements – 8000 m long x 3 m wide = 24000 litres of DS-11-LB Dust Suppressant required.
Using the Spray On Application Method:Add 0.02 litre of • DS-11-LB Dust Suppressant / litre
of water
1lt mixture per m2 to be mixed into the road surface • for stabilization
Once sufficient compaction, shape and quality have • been achieved, apply 0,7 litres/m2 of DS-11-LB Dust Suppressant diluted mixture on surface
Balance of litre which is 0.3 litre will be sprayed once • a week and then a maintenance coat every 2 weeks of 0.03 litres/m2
DS-11-LB Dust Suppressant Spray Equipment For Roads Or Broad acre Applications
There are generally two methods of applying the • DS-11-LB Dust Suppressant liquid to the road surface and this is dependent on the volume and frequency of application. For small scale application, a portable tank with a pump and hand spray unit may be used as depicted below.
To increase surface wetting, use nozzles that produce • a large number of small drops and decrease the contact angle of the spray on the material. Spraying done manually is very much a hit and miss operation which requires expertise acquired by operator experience.
The application to large areas on a continuous • basis will require a tanker fitted with a spray bar unit. Application equipment should be capable of distributing the DS-11-LB Dust Suppressant in a uniform manner at an application rate specified.
Pressure Distributors
Pressure distributors shall be propelled by a power unit capable of accurately maintaining any speed required for spraying and shall be provided with the following minimum equipment:
A pump capable of developing a uniform pressure • within the required range.
A pressure gauge indicating the pressure within the • spray bar that is accurate to 15 kPa and visible to the operator.
A rear mounted spray bar having a positive and • instant shut off that can be set at variable heights parallel to the surface and to any spraying width form 1-3m to spray any portion of the roadway surface, including the shoulders.
The spray bar nozzles should be: • • All the same manufacture and size • Clean and in good working condition • Designed and set to ensure uniform fan shaped spray without atomization. • Nozzles should be set in the spray bar at an angle permitting each spray fan to pass behind the other in such a manner that the fans on either side would substantially spray the area that would otherwise be missed should there be a malfunction of one nozzle.
A strainer installed in the feed system to prevent • clogging of the spray bar nozzles.
A measuring stick graduated in 200 litres increments • calibrated for the particular tank and so identified.
DS-11-LB Dust Suppressant• can be used as a dust suppressor on conveyor belts and throw over points where water is normally injected. It is advisable to have a venture system or an auxiliary pump which injects the concentrated DS-11-LB Dust Suppressant solution into the main water feeder system.
Spray Bar Schematic
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
Spray Nozzles: Set spray nozzles to the desired width, height and output rate. Test equipment (off-site) if necessary.
Coverage:
The spray nozzles should provide an even coat over the treated area with each pass.
Spray Rate:
Set the spray rate high enough to allow even coverage with multiple coats yet low enough to prevent material from draining away from the treated area.
How to Clean The Application Equipment:
Rinse: Rinse of all application equipment thoroughly with water until clean. If the DS-11-LB Dust Suppressant is allowed to dry, use water to rinse and remove residue.
Traffic:
Treated areas may be opened to traffic immediately.
Curing:
No curing period is required.
DS-11-LB Dust Suppressant Storage & Handling
As mentioned previously, the viscosity of DS-11-LB Dust Suppressant is relatively high and requires a substantial pump for delivery into and out of bulk tanks. The types of pumps generally used are petrol driven centrifugal type units capable of high volume output.
The pumping system needs to operate on minimum piping (flexible or ridged) diameter of 50mm. The petrol
or diesel units are driven by 3.5 or 5.0 HP motors which are more than capable of pumping viscous liquids such as DS-11-LB Dust Suppressant whereas an equivalent electrically driven unit would be bulky and probably be a three phase unit which is expensive. The petrol driven units are relatively inexpensive and have the advantage of being highly mobile. Another option is a pneumatically driven diaphragm pump or “sandpiper” type which is very common to the mining industry.
In terms of storage, plastic bulk tanks are suitable, provided that the medium to heavy duty units are used. The specific gravity of the DS-11-LB Dust Suppressant is 1.26 times as heavy as water and could result in conventional water tanks bursting. If absolutely necessary, a light gauge tank would require strapping at strategic intervals to strengthen the tank. LTSA recommends the use of two by 15000 litre units coupled together with a gate valve between the piping. A single 30000 litre unit would be too high to pump from the bulk tanker and would require a long step ladder for access to the manhole situated on top of the tank.
Frequently Asked Questions:
Q: Product is expensive in comparison to water
A: Water is in short supply and it is a valuable commodity, water will have to be applied +/- 6 times per day on a hot day, DS-11-LB Dust Suppressant only needs to be applied +/- 2 times per month. You would also need to hire a water cart if you don’t have one and that can be costly per day and most times you would need more than one.
Q: How often do you need to apply DS-11-LB Dust Suppressant
A: This all depends on the condition of the road. You need to do the initial application and thereafter keep up the rejuvenation +/- every month or when you can see the road getting dusty.
DS-11-LB Dust Suppressant Spray Equipment for Conveyors and Throw Over Points
Typical On SIte Bulk Tank Installation
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
1Water
Short Term
2Water Optimizer
Short Term Cost Saving
3Water Extender
Short Term Cost Saving
Surface Bonding
4.1Soiloc
Long Term Surface Cosolidation Erosion Protection
4.2DS-11-LB Dust Suppressant
Long Term Surface Consolidation Haul roads and
trafficable areas
A step-by-step look at dust control and water management
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
Water as a Dust SuppressantThis is the most commonly used method for dust control
Drawbacks to consider:The availability of water is a growing world wide •
concern
The cost of obtaining the water•
These costs are mostly hidden as pump costs, • electricity and vehicle wear and tear are not always calculated into the costs of dust control
Hyper saline water is corrosive and environmentally • damaging
Use of Water OptimizersThe use of Water Optimizer or extenders can be seen •
as the first step towards effective dust control.
These additives extend the effectiveness of water • when applied.
Wetting agents improve absorption of water into • the soil by reducing surface tension and consequently reducing evaporation
Water optimizers increase water use efficiency by up • to 30%
These products offer a limited short term solution and • are consequently continually reapplied.
The Use of PolymersThe use of polymer based dust suppression is •
recognised as the most effective form of dust control
A polymer is a large molecule composed of repeating • structural units
Although the term polymer is sometimes taken to • refer to plastics, it actually encompasses a large class of natural and synthetic materials
Both synthetic and natural polymers are used in road • stabilization
This applies to haul roads and other trafficable • surfaces.
The benefits of these type of products include • reduced water application more stable road surfaces and a long term sustainable management program.
DS-11-LB Dust Suppressant• is a natural polymer
What is DS-11-LB Dust Suppressant?DS-11-LB Dust Suppressant• uses a binding agent
called Lignosulphonate
Lignin is the constituent in wood which binds • cellulose fibers together
Lignin is extracted from wood pulp as a byproduct in • a paper manufacturing process
DS-11-LB Dust Suppressant• works by bonding road base particles together
The • DS-11-LB Dust Suppressant bond is largely mechanical rater than chemical
Lignosulphonate products have been used in • construction, agriculture, food and mining industries for nearly fifty years.
Lignosulphonate is internationally rated, non toxic • and no irritant
DS-11-LB Dust Suppressant• is non corrosive
DS-11-LB Dust Suppressant• is a natural product – its production and use is environmentally sustainable
Dust and the EnvironmentThe active ingredient in • DS-11-LB Dust Suppressant
is Calcium Lignosulphonate.
This product that has been used widely in agriculture, • food, construction and dust suppressance for almost fifty years.
It is generally accepted that lignosulphonates are • the most environmentally acceptable dust palliatives currently in use.
This applies to the synthetic polymers as well as the • chloride group of chemicals.
To date, world wide, we have been unable to find • any environmental or OHS claims based on the use of Lignosulphonates
Unlike some Lignosulphonates, particularly from • China, DS-11-LB Dust Suppressant is certified free of Dioxin
Dioxin is generally produced by acid catalysed • dehydration of diethylene glycol
DS-11-LB Dust Suppressant• is produced from a process free of DEG
DS-11-LB Dust Suppressant• meets United States EPA levels for elemental contamination, in relation to EP toxicity.
This applies inter alia to chloride, sulphur, sodium, • potassium, iron, magnesium, mercury, lead and arsenic
The use of • DS-11-LB Dust Suppressant significantly reduces water required in fugitive dust abatement
DS-11-LB Dust Suppressant• is non corrosive – in contrast to products based on magnesium chloride.
DS-11-LB Dust Suppressant• is less soluble than magnesium chloride and consequently more likely to remain in the road base profile after rain incidents
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
Dust and the Environment - continuedConsequently • DS-11-LB Dust Suppressant is less
likely to be leached into surrounding eco systems or water tables
DS-11-LB Dust Suppressant• has an extremely low mammalian toxicity
DS-11-LB Dust Suppressant• is digested and decomposed by normal soil bacterial processes this too is in contrast to synthetic polymer and chloride based products
Road Management Using DS-11-LB Dust SuppressantMining Haul Roads – Dust Suppression and Road Stabilization
The quality of road base material is often inadequate•
OHS mining and environmental regulation requires • dust emissions be controlled
Haul roads are characterized by high volume, heavy • impact traffic patterns
Inadequately stabilized roads:decrease efficiency through increased operating costs •
and down time
increase accident risk through poor visibility•
have an adverse effect on worker health•
have an adverse environmental impact•
require ongoing maintenance•
Stabilised Roads:
•- reduce road maintenance costs
•- reduce overhead costs
•- increase transport efficiency
•- increase financial performance
DS-11-LB Dust Suppressant Application - Rates
DS-11-LB Dust Suppressant• bond is mechanical not chemical
Road base soil type is less important than size • composition of the aggregate
Road design ideally needs to comply with best • practice construction principals
The initial application is 0.2 to 0.8 Litres of • DS-11-LB Dust Suppressant per square meter of road surface area
0.2 l/m2 • DS-11-LB Dust Suppressant application for Dust suppression;
- parking, road verges and laydown areas
0.8 l/m2 areas of greater impact require Road • stabilization; - Roads with high traffic speed and density - Road surfaces, above ground, haul, access and service roads - Below ground applications
DS-11-LB Dust Suppressant Application PracticeInitial Application
Initial application of • DS-11-LB Dust Suppressant (0.2 to 0.8 litres/m) diluted into between 6 to 8 spray applications.
This is to achieve required surface penetration.•
This is dependent on the rate of infiltration and is site • specific.
An infiltration test can be carried out in order to • predict the required number of primary applications.
Maintenance ApplicationsOn a monthly basis at 10% solution of the primary •
application.
For example heavy use areas treated at 0.8 litres/m2 - • fort-nightly application at 0.04 litres/m2 be applied
DS-11-LB Dust Suppressant Maintenance ProgramThe following is an example of a recommended ongoing maintenance program:
Week one post initial application – a single application • of water at a rate to allow road base infiltration.
Week two a single application @ 5% of the initial • application
Week three water only - as in week one above•
Week four single application @ 5% of the initial • application
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Magnesium Chloride
Product Description: Concentrated brine that pulls water out of the air. This product sinks into the road and creates a tight, hard, compact surface that resists abrasion. Dust control is by keeping the road surface damp.
Pros Cons
Aids in road surface compaction. Corrodes metal
Readily available Rain causes sloppy conditions
Road can be re graded Minimum curing time 24 hours
Rainfall does not totally deteriorate the product Requires relative humidity greater than 32% at 250
Limited hazard to workers No cementing action
Increases road stability High concentration toxic to plants and water catchments
Leachable under high rainfall conditions
Petroleum Based Emulsions
Product Description: Petroleum based emulsions (resins combined with wetting solutions). Dust control is by cohering to and coating dust particles to form a cohesive membrane that adheres to other particles.
Pros Cons
Long-tern effectiveness Requires special dedicated equipment
Not water soluble when dry and therefor does not leach Potholes may develop due to rigidity and variable soil base
conditions
Provides soil stability Long term application makes grading difficult
Suitable for a wide range of soils Environmentally less acceptable
No relative humidity requirement
Does not attract animals
Limited hazard to workers
Strong bonding action
Lignosulphonates
Product Description: A co-product from the pulping process. Dust control is by gluing and bonding soil particles together
Pros Cons
Long-tern effectiveness is good as the product remains slightly
plastic and can be graded and reformed
Discoloration due to red brown color. This applies to vehicles and
run off
Less water soluble and therefor does not leach to the same extent
as MgCl2
Leaching under high rain fall conditions
No relative humidity problems May increase biochemical oxygen demand (BOD) in water
Suitable for a wide range of soils Wearing surface needs 4-8% fines
Minimal hazard to workers Residual acidity in non neutralised product may cause corrosion
Can be mixed with calcium salts (hydroxide or carbonate). Lime
extends effectiveness and provides tighter road surface with less
gravel loss
May be brittle when dry and slippery when wet
Limited hazard to workers
Strong bonding action
Can be used with hyper saline water
Competitor Products
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Parameters
Product
Hig
h P
I mat
eria
ls (P
I>10
)
Med
ium
PI m
ater
ials
(PI b
ete.
3 -
10)
San
dy
Pi M
ater
ials
(PI <
3)
All
Wea
ther
Acc
ess
Ste
ep g
rad
ient
s
Hea
vy V
ehic
les
(min
e/q
uarr
y)
Hig
h tr
affi
c vo
lum
es (>
250
vp
d)
Sho
rt t
erm
ap
plic
atio
ns (d
eto
urs)
Long
ter
m a
pp
licat
ions
(mai
nten
ance
pro
gra
ms)
Sp
ray
on
app
licat
ions
Mix
in a
pp
licat
ions
Gra
der
mai
nten
ance
Wetting agents
Hydroscopic Salts
Natural Polymers
Synthetic Polymers
Modified Waxes
Petroleum Resins
Bitumen Dependant on characteristics of individual products
*Other products can be applied as long term applications, but will require periodic rejuvenation
Product Comparison
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ENVIRONMENTAL EFFECTS OF APPLYING LIGNOSULFONATE TO ROADSBy JAMES W ADAMS, DAISHOWA CHEMICALS INC, Research & Development, February – 1988
SUMMARY
The overall impact on the environment from applying lignosulfonates to roads is negligible. They are safer to use for stabilisation and dust control than any competing class of chemicals.The manufacture of lignin involves evaporation; the evaporation process drives off any volatile contaminants such as acetic acid. Corrosion and toxicity towards plants can be readily minimised by pH control and lignosulfonates are non-toxic to animals.
Lignosulfonates have been applied to roads, used in animal feeds and converted into human foods for more than 30 years without problem. This comes as no surprise after learning that the products have the following properties:
No dioxins present. No other organics present at • hazardous levels
Toxic trace minerals are below EP Toxicity limits*•
Low order of toxicity towards fish•
Non-toxic orally and non-irritating to the skin or eyes • of animals
No human health problems attributed to exposure•
Very low toxicity towards plants•
Residuals are resistant to decay•
When spread on land, there is no risk of contaminating ground water. Published data indicate that at less than 10 kgs per square meter, no problems arise. This is much above the 1 kgm/square meter required for stabilisation and 0.3 kgm used for dust control. The non-hazardous features and abundant supply of lignosulfonate make it a good material for treating roads (1). It is widely used in Sweden and California – two of the world’s most environment-conscious areas.
PRODUCTION
In the sulfite pulping of wood, lignin – nature’s binder – becomes soluble and is separated from the pulp fibers as spent liquor (SSL). This liquor also contains the naturally occurring wood sugars.
Dilute SSL at 12% solids is treated and concentrated to 50 – 60% solids by evaporating water. Starting from this base material, a family of chemicals has been developed.
They are known as lignins or lignosulfonates.
They are used in the following applications:
Water Treatment Chemicals•
Oil Well Drilling Mud Additives•
Components of Adhesives•
Textile Dye Dispersants•
Animal Feed Pellet Binders•
Gypsum Dispersants for Wallboard•
Concrete Additives •
Leather Tanning Agents•
Road Binders•
Dispersants for Brick Clay•
Feed Molasses Additives •
Battery Plate Expanders•
* As set by the U.S. Environmental Protection Agency
Of the 1.32 million tons of lignosulfonate sold worldwide, 150,000 tons are sold for application to roadways – 80,000 tons in North America and 70,000 tons in Europe and Australia. The product used on roads is the base product that has not been chemically modified and may be the calcium, sodium or ammonium form depending on the pulp mill (36). Complex lignofsulfonates are sophisticated, high technological content chemicals, showing all the chemical complexity of the naturally occurring lignin from which they were derived.
SUGARS
The types of sugars present in lignofsulfonate will change depending on the kind of wood pulped.Wood from needle-bearing trees yield predominantly the hexoses-mannose, glucose and galactose.Wood from leaf-bearing trees yield predominantly the pentoses-xylose and arabinose. We do notpulp maples!
ENVIRONMENTAL EFFECTS
(a) Dioxins:
During the evaporation of spent liquor, SO2 and any volatile components are removed. However, with attention recently focused (38) on the presence of dioxins in paper mill effluents, the U.S. Environmental Protection Agency approved laboratory – Enseco Inc.,was contracted to determine the dioxin content of SSL road binder. Results from analysing a7-day composite of Lignosol B, (a calcium lignofsulfonate) (37) show that it contains no detectable amounts of 2, 3, 7, 8 – tetrachloro dibenzofuran or 2,3 7, 8 – tetrachloro ibenzop-dioxin. This is not surprising as chlorinated organic contaminants require the presence of substantial chlorine concentrations.
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This can come from:Using chlorinated biocides after bleaching•
Bleaching fibers with chlorine, hypochlorite or chlorine dioxide•
But the Quebec mill (REED) does not bleach. Mills that do bleach only do so after thelignosulfonate has been separated and removed from the system.
(b) Trace Elements:
Lignosulfonates are wood extracts that contain the mineral elements naturally present in trees. Depending on the tree type and soil on which it was grown, the wood contains different kinds and amounts of minerals. Element analysis of tree barks that are typical for plant residues were published by Harder and Einspahr (12).
The U.S. Environmental Protection Agency (EPA) has recently defined the maximum concentration of elements to establish EP Toxicity (5). Limits are shown in Table 1.
Table 1
MAXIMUM CONCENTRATION OF CONTAMINANTS FOR CHARACTERISTIC OF EP TOXICITY
EPA Hazardous Waste No. Contaminant Maximum Concentration ppm
D004 Arsenic 5.0D005 Barium 100.0D006 Cadmium 1.0D007 Chromium 5.0D008 Lead 5.0D009 Mercury 0.2D010 Selenium 1.0D011 Silver 5.0
REED’s lignosulfonate products are submitted periodically for Proton Induced X-ray Emission analyses. The testing procedures can detect all eight of the EP Toxicity contaminants plus 67 others. Results on REED products (7) are reported in Table II. Note that barium, cadmium, mercury, selenium and silver could not be detected. The other EP Toxic elements are present at levels below the maximum concentration.
Table 11
TRACE ELEMENTS IN LIGNOSULFONATES. Reed Calcium Lignosulfonate
Concentrate Neutralized Concentrate
Titanium 5.6 2Aluminium - -Silicon 105 241Phosphorus 540 516Manganese 118 155Iron 207 869Cobalt 1.8 6.6Nickel 0.9 1.4Copper 2 1.2Zinc 25 31Gallium 0.3 -Bromine 0.7 0Rubidium 3.7 2.5Strontium 32.5 34Zirconium 1.8 1.6Molybdenum 0 2.5Arsenic 0.1 -Barium - -Cadmium - -Chromium - 2.7Lead - 0.3Mercury - -Selenium - -Silver - -
Neutralisation adds some trace minerals as they are contributed by the naturally occurring limestone that is used in the neutralising process.
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ACUTE ANIMAL TOXICITY:
During the past 22 years, many of REED LIGNIN’S products have been examined. All of them proved to be non-toxic. Table III shows the results for 18 widely used products. The basic lignin used on roads would be even more innocuous (22).
To assess health risks involved in handling a new chemical, it is tested for acute toxicity in white rates and skin and eye irritation on rabbits. If all 10 rats in a test survive a one-time feeding dose offive grams/kilogram of body weight, the product is considered non-toxic according to the Occupational Safety and Health Administration (OSHA) rule, printed in the U.S. Code of Federal Regulations 29 CFR 1910.1200 (4). If rats do not survive the five gram/kilogram feeding level, testing is conducted to find the dose that kills 50% of the rats (LD50).
Empirical scores are used to report results for skin and eye irritation tests with a skin irritation score of less than five needed to rate a material non-irritating to the skin. Testing for eye irritation is done following instructions in the Code of Federal Regulations 16 CFR 1500.42. The Hazelton Laboratory report on testing the lignin product, Additive-A Type 3, (10), is typical for doing this kind of work.
Table 111
PRODUCT TEST LAB DATE
ORAL TOXICITY
ON WHITE RATS,
LD 50g/kg
RABBIT SKIN IR-
RITATION INDEXRABBIT EYE IRRITATION SCORE
24 hrs 48 hrs 72 hrs
Maracell XE WARF 1977 >5 0 0.33 0 0Marasperse N-22 WARF 1975 0 0 0 0Marasperse CB WARF 1975 0 0 0 0Marasperse CE-22 WARF 1977 >5 0.17 2.0 0 0Marasperse B-22 WARF 1975 0 0 0 0Marasperse OS Raltech 1978 >5 0 0 0 0Marasperse N-3 Raltech 1978 >5 0 0 0 0Marasperse CBOs-3 WARF 1977 >5Marasperse CR-23-7 WARF 1977 >5 0.21 0.67 0 0Marasperse XCB-2 WARF 1977 0.17 0.67 0 0Norlig 41 WARF 1975 0 0 0 0Norlig 41D WARF 1975 0 0 0 0Norlig 41N WARF 1976 >5 0 0 0 0Norlig 412 Raltech 1978 >5 0.2 0 0 0Additive-A, Type 3 Hazelton 1985 >5 1.5 0 0 0Americo SD-1 Raltech 1978 >5 0 0 0 0Kelig 32 WARF 1977 0 0 0 0Kelig 32-2 Raltech 1978 >5 0.1 0 0 0
Reed’s roadbinder is among the Norlig 41 class of products.
SUBACUTE TOXICITY:
In 1960, American Cyanamid, Hercules Powder, NOPCO Chemical and Socony Mobil OilCompanies sponsored a study at the Industrial Bio-Test Laboratories to Determine the 90-daysubacute oral toxicity of a REED sodium lignos-fulfonate, Marasperse N.
Seven groups of 14 white rats were fed chow containing 0, 0, .01, .05, .20, 1.0 and 5.0% MarasperseN for 90 days. Results were reported by Kay and Calandra (15).
None of the five dietary levels of Marasperse N had adverse effects on the growth of rats•
Only small differences were found for food consumption and food utilisation•
No dose-correlated trends were apparent in mortality data•
No significant abnormal behaviour was noted among animals of any group•
Periodic blood studies disclosed no adverse findings•
Urine analysis revealed no significant abnormalities•
No significant gross pathological findings were noted at autopsy of sacrificed animals•
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CHRONIC TOXICITY:
For effects of long-term exposure there are the good health records for those who have worked with reacting and spray drying this material. Over a period of 40 years to date, no human health problem has been attributed to exposure to lignosulfonate.
Before using lignosulfonate in poultry and animal feeds, calcium, sodium and ammonium forms ofSSL were scrutinised very carefully for long-term health effects. Results of studies conducted to get approval to use the SSL products in animal feeds were obtained from the U.S. Department of health & Human Services under the Freedom of Information Act (25). After reviewing data filed with Food additive Petitions No. 706 and 1239, the Commissioner of the Food & Drug Administration ruled on August 15, 1962 that:
“…….The Division of Food concludes that the product is reproducible, of uniform composition, and that it accomplishes its intended technical effect of pellet binding. Analytical method is available for regulatory purposes.
The Division of Pharmacology concludes that use of the additive in animal feed under the proposed conditions of use in animal feed is safe. The Division of Veterinary Medicine concludes that the additive is safe for use in animal feeds and effective as a pelleting aid. Mr Philbeck, Meat Inspection Division, ARS, U.S.D.A., offers no adverse comment to this order.”
Today, 30 years after lignins were introduced into animal feeds, no chronic toxicity problems have arisen. This is not surprising, after all – hay, grain and forage contain 20% lignin.
FISH TOXICITY:
Because a lot of water is needed for transporting, processing and pulping wood, paper mills located near oceans, lakes and rivers. Many studies have been conducted to measure the water polluting effects of the following:
Wood transport•
Debarking•
Pulping•
Fiber washing•
Fiber bleaching•
Paper making (6, 20, 21, 31, 32)•
But, most of the studies have been concerned with spent liquor prior to evaporation, whereas lignosulfonate products, sold for road de-dusting are SSL concentrates. When removing water in evaporators sulfur dioxide, acetic and formic acids are distilled off leaving liquors that are less toxic than the raw material. Published information about various lignosulfonates are summarised in TableIV along with reference toxicity values for familiar products.
Evaporating water and volatiles from dilute calcium and sodium SSL substantially reduces toxicity to the point where fish can tolerate 3,000 rather than 1,000 mg/l of solids. With purified lignosulfonates the tolerance is increased to 7,000 mg/l (27). The common salts calcium chloride, sodium chloride and sodium sulfate have LC50 96-hour values in the 5,000 – 10,000 range (8). In reference books (18,28) the cut-off point for LC50 96-hour values is 1,000 mg/l. Compounds with values greater than this are given a value of >1,000 and are considered to have a low order of toxicity. Calcium and sodium lignosulfonates, calcium chloride, sodium chloride and sodium sulphate all are in this category. By contrast, the popular laundry detergent Tide and surfactants used in making such products are very toxic toward fish (14). Values ranging from 4 – 50mg/l are reported for these materials in Table IV.
Table IVTOXICITY OF WATER SOLUBLE MATERIALS TOWARD FISH
REFERENCE FISH LIGNOSULFONATE TESTED LC50 – 96 hours mg solids/litre
Wilson Rainbow Trout Lignosol BD (Quebec) 3,700Stapanian Rainbow Trout Lignosite (west Coast) 2,125Wilson Rainbow Trout Lignosol XD 3,500Roald Rainbow Trout Purified Na Lignosulfonate 7,300Canada Various Calcium Chloride 5,000Jones Various Sodium Chloride 6,000Jones Fathead Minnows Sodium Sulfate 9,000Jones Fathead Minnows Tide Laundry Detergent 50Jones Fathead Minnows Sodium Dodecylbensene
Sulfonate
4
Jones Fathead Minnows Sodium Lauryl Sulfate 5
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PLANTS:
With any liquid material that is applied to roadways, there is concern about harming plants that grow near the roads. Treating dirt roads with lignosulfonate to stabilise them for carrying vehicle traffic requires mixing 15 tons of solid per mile in the top six inches of soil on a 24-foot wide road. To do this, lignosulfonates are diluted with water. After spraying on the roadway, a road grader or scarifier is used to mix the binder with soil. Compacting with a roller is done soon after mixing.
For dust control, only 2.5 tons of solids per mile are sprayed on pre-moistened dirt roads. This total amount is usually applied in two applications. In recent years both techniques have been used in Europe and North America. They account for thesale of 150,000 short tons of lignosulfonate solids that are used to treat 20,000 miles of road way.No complaint of plant damage has been reported from this wide exposure (30). This is not a surprise after reading details of a very bold experiment that Stapanian and Shea (29) conducted. They applied Lignosite, a 50% solids calcium lignosulfonate, directly to the ground cover of Douglas Fir plantations in the state of Washington. Very high application rates of 21, 42 and 63 tons of solids per acre were applied to twelve 5 x 10m (16 x 33 feet) plots of forest land. Four plots received the same treatment. These treating levels are way above the 5 and 1.3 tons of solids per acre applications used for stabilising and de-dusting roads.
Observations made periodically up to 12 weeks after the Lignosite was applied, indicated that the woody vegetation was not affected. The biomass of herbaceous plants was significantly decreased only at the two highest application rates. The growth of Douglas Fir trees was not significantly affected.
In another study Gast and Early (9) reported on the phytotoxicity of three commercial lignosulfonates toward garden crops, cotton and tobacco. This work was done with ingredients used for pesticide formulations. Of the 77 products tested, Marasperse C, Marasperse CB and MarasperseN were the least toxic. Pertinent results are reproduced in Table V. Lignosulfonates are now widely used in herbicide and pesticide formulations. Chlorides are not expensive in California and, like lignins, are often used for dust abatement.However, at relatively low dosage chlorides can kill vines and care is suggested when applyingthem (19).
Table V
PHYTOTOXICITY RATINGS
Plant Injury: 0 = None, 1 = Slight, 2 = Moderate, 3 = Heavy, 4 = Severe
PLANT Conc in water applied % Marasperse C (calcium
Lignosulfonate)
Marasperse CB (sodium
Lignosulfonate)
Marasperse N (sodium
Lignosulfonate)
LEAVES
Bean 1.0 0 1 00.1 0 0 0
Corn 1.0 0 0 00.1 0 0 0
Cotton 1.0 0 0 00.1 0 0 0
Cucumber 1.0 0 0 00.1 0 0 0
Tobacco 1.0 0 0 00.1 0 0 0
Tomato 1.0 0.5 0.3 00.1 0 0 0
ROOTSTomato 1.0 4 1 4
0.1 0 0 00.01 0 0 00.001 0 0 0
Tobacco 1.0 0 0 00.1 0 0 0
GROUNDWATER:
The effect of lignosulfonate on groundwater is related to concentration. Applying 4,000 tons of dissolved solids each year to the same acre of porous soil will drive the liquor down into the groundwater with no time for destruction by fermentation. Results from ponding studies are vivid demonstrations. With much more modest one-time applications of 20 – 60 tons / acre Stapanian(29) indicates slow movement and time for fermentation which should pose no threat to contaminating groundwater. With no serious groundwater contamination expected at 50 tons/acre, applying 5 and 1.3 tons/acre for road paving and dust control would not be a serious matter.
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DECAY / BIOLOGICAL OXYGEN DEMAND:
Sugars and carbohydrates are easily fermented by many different microbes. With as much as 35%of these easily fermented substances present in lignosulfonate, and few toxic materials around, it isno surprise that partial decay occurs quickly. In fact, lignosulfoante is used as a fermentation media for the commercial production of ethyl alco-hol, fodder yeast and food-grade yeast. Because of the wood sugars, lignosulfonates are not added to waterways containing fish and a marginal supply of dissolved oxygen. Microbes will feed on the sugars and consume oxygen in the process.
Results of many tests on basic lignosulfonate indicate that its five-day Biochemical Oxygen Demand (BOD5) is 0.23 pounds per pound of solids. Microbes acting on 100 pounds of basic lignosulfonate for five days require 23 pounds of oxygen. The 100 pounds of lignin must be mixed with 394,000 gallons (1,500 cubic meters) of water containing 11 ppm dissolved oxygen to wind up after five days with water containing 4 ppm dissolved oxygen. The 4 ppm dis-solved oxygen is where fish kill first appears. This means that 30 ppm of SSL solids will allow dissolved oxygen at a safe level. More complex lignosulfonates show lower BOD5 values.
During the 1960s, much attention was given to laundry detergents that produce voluminous and persistent foam in discharge waterways. The problem was traced to sudsing surfactants that biodegraded very slowly. In developing new sudsing surfactants, River Die away was the most popular test used for measuring biodegradation. The test was applied to examine lignosulfonates. Small amounts of lignosulfonate, dissolved in aerated Wisconsin River water, were held at room temperature for 33 days. Samples removed periodically were tested for organic matter content by oxidising with dichromate to determine the Chemical Oxygen Demand (COD). Data showed that Norlig A, a lignosul-fonate road binding material, degraded 28% in five days and 43% in 33 days.This closely corresponds to the car-bohydrate content of the product, and indicates that pure lignin resists decay. Pure lignin is the last to go in natural decay processes.
The 54% material remaining after 33 days of incubation persists as a road binder, and will show as natural lignin colour in waterways. It is a situation much like the brown colour imparted to stream sand lakes by humus and humic acids produced in the decay of plants and trees.
CORROSION:
Severe corrosion of automobile under parts is usually associated with the use of salts for de-icing roads during winter months. This is not always so. A study by the Swedish Highway Department(17), indicates that in areas where calcium chloride or magnesium chloride is used for keeping dust down on dirt roads, automobile corrosion from this source is more severe than from salts used for road dicing(16).
Because of the nature of their binding mechanism, lignins absorb onto soils and clays and form cohesive bonds. This is very different from calcium chloride which is loosely concentrated on the surface of the road from where it is easily blown into passing vehicles where it can start its insidious corroding activity.
DISCUSSION:
This survey of lignin and the environment has only touched on the subject. However, a full reference index is attached for those wishing to study the subject in greater depth. Any open minded analysis of the data will conclude that the use of lignin for dust control and road stabilisation is not only environmentally safe, but is more “environmentally friendly” than any other dust palliatives available.
REFERENCES:U.S. Bureau of Mines Information Circular 7806.1.
Beak, T.W. Consultants Ltd., Anaerobic Contact Filter for Treatment of Waste Sulfite Liquor, CPAR Project Report 103-1, 2. March 31, 1973.
Benning, R., Corrosion Rate of Norlig 11 and Norlig 41, American Can Co. memo to R Peiser, September 19, 1972.3.
Code of Federal Regulations, 29 CFR 1910.1200, Revised as of July 1, 1985, p 888.4.
Code of Federal Regulations, 40 CFR 261.24, Revised as of July 1, 1987.5.
Doudoroff, P and Katz, M., Critical Review of Literature on the Toxicity of Industrial Wastes, Sewerage and Industrial Wastes, 6. 22 1432 (1950).
Element Analysis Corporation report December 5, 1986 in the Rothschild files under 55 Res. and Consulting Labs.7.
Enviro Technical Information for Problem Spills – Calcium Chloride. Environment Canada – Environmental Protection Service, 8. May 1984.
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Gast, R and Early, J., Phytotoxicity of Solvents and Emulsifiers used in Insecticide Formulations, Ag. Chem.,p 43 (April 1956)9.
Glaza, S. Final Report on Toxicity of Additive A – Type 3, Hazelton. Laboratories Report to J. Adams of Reed Lignin, October 10. 11, 1985.
Griffin, J and West, J., Acute Toxicity of Ammonia-Base Neutral Sulfite Pulp Mill Waste Liquor to Rainbow Trout. Bul. of Envir. 11. Contam. and Toxicol. 15 No. 5., 608 (1976).
Harder, M., and Einspahr, D., Levels of Some Essential Metals in Bark, Tappi 63 110 (Dec. 1980).12.
J V Belle. Paper mill by-product used for dust abatement. Public Works. July 1971.13.
Jones, J., Fish and River Pollution. Butterworths, Washington (1964) p 122.14.
Kay, J and Calandra, J., Industrial Bio-Test Labs report to the NOPCO Chemical Co., Ninety-Day Subacute Oral Toxicity of 15. Marasperse N, September 19, 1960.
Data available from Holmens Bruk AB. 546800 Vargon, Sweden.16.
Lecture 09-03-1987, Logging Roads Maintenance Forestry School Course (Sweden).17.
Lewis, R and Tatken, R., Registry of Toxic Effects of Chemical Substances, 1979 Edition, U.S. Dept of Healthand 18. Human Services (Sept, 1980).
Private communication. ITT (Rayonier) Wash. U.S.A.19.
Marier, J., The Effects of Pulp and Paper Waste with Particular Attention to Fish and Bioassay Procedures for Assessment of 20. Harmful Effects. National Research Council of Canada Report No. 13501.
McKean, W., Pulp and Paper Ind. ch. in Introduction to Environmental Toxicology, Guthrie, F., and Perry, J.Ed. Elsevier, N.Y.21.
See Reed Lignin General Brochure under Toxicology.22.
Details available from Special Mining Services Pty Ltd., Lochinvar, Australia.23.
National Association of Corrosion Engineers Handbook – Fifth Ed. Corrosion data summary – Metals Section.24.
Nichol, M., Freedom of Information Act response from the U.S. Dept of Health and Human Services – Ref.F85- 25. 7578 Letter to T. Winowiski, July 11, 1985.
Revall, M., Corrosivity of Spent Sulfite Liquors Toward Rail Tank Car Steel. Institute of Paper Chemistry Report on 26. Project 3614, August 19, 1987.
Roald, S., Acute Toxicity of Lignosulfonates on Rainbow Trout, Bul. Envir. Contam. Toxicol. 17 No. 6, 702(1977).27.
TSax, N.I., Dangerous Properties of Industrial Materials, Sixth Ed., Van Nostrand Reinhold Co., N.Y., p.618.28.
Stapanian, M and Shea D., Lignosulfonates: Effects on Plant Growth and Survival and Migration Through the Soil 29. Profile, Inst. J. Environmental Studies 27 Vol 27, 45 (1986).
Van Belle, J., Paper Mill By-Product Used for Dust Abatement, Public Works, p.51 (July 1977).30.
Walden., C.C., The Toxicity of Pulp and Paper Mill Effluents, Water Research 10, 639 (1976).31.
Walden, C and Howard, T., Toxicity of Pulp and Paper Mill Effluents, Tappi 60, 122 (Jan 1977).32.
Williams, R., Toxic Effects of Sulfite Waste Liquor on Young Salmon. Washington Dept of Fisheries Research 33. Bulletin No. 1. (1953).
Wilson, M. and Chapell, C., Reduction of Toxicity of Sulfite Mill Effluents, Can. Forestry Service CPAR Project 34. Report 49-2, March 31, 1973.
Wilson, R., Acute Toxicity of Spent Sulfite Liquor to Atlantic Salmon. J Fisheries Res. Board of Canada 29,1225 (1972).35.
Reed (calcium), Temfibre (ammonium), ITT (sodium), etc.36.
Miille, M J and Luksemburg, B., Laboratory Report 33353, Enseco Inc., West Sacramento, CA, February 24,1988.37.
Paavila, H.D., Dioxin and Certain Pulp and Paper Processes, Report to the Canadian Pulp and PaperAssociation, 38. August 1987.
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Definition: Calcium Liquid Sulphate- CLS1. INTRODUCTION
Standard road safety is measured by skid resistance. Slippery road surfaces are a major cause of accidents on any type of road. Skid resistance involves the complex interaction of the road surface, vehicle and environmental factors. Since the road surface is not a variable for purposes of this tests, the tests compares the skid distance of different vehicles, at different speeds on a typical mine gravel haul road. The road surface was prepared on different sections with water, CLS (standard application) and CLS (overdose) and compared to untreated standard gravel road surface (the test control). The results indicate which of water or CLS has the greater effect on the skid resistance on gravel road surfaces at the mine.
2. SKID RESISTANCE
Skidding is the jerking of the wheels of the vehicles when it locked due to sudden breaking, if the frictional resistance offered is too low. The friction that can be mobilized is greater than the decelerating force, the vehicle comes to a safe halt within a certain distance. If the friction developed is much smaller than the decelerating force, the vehicle cannot be controlled by the driver. Skid resistance is the force developed when a tyre is prevented from rotating along the road surface. Skid resistance is thought of as a road surface property; it is the antonym of slipperiness.
2.1 FACTORS AFFECTING THE SKID RESISTANCE SURFACES
Different types of road surfaces have different skid resistance properties. Asphalt surfaces have more skid resistance property than gravel. The macro texture helps in providing a good drainage of the surface & the deformation of the tyres. The macro texture property of the pavements brings into play the hysteresis property of friction.
2.2 WATER & TYRES
Water lowers skid resistance on any surface. The contact surface divided into 3 zones:
Zone1- Bulk displacement of water.•
Zone 2 - Water carries a portion of load.•
Zone 3 - Tyre in contact with surface.•
The thread depth and the pattern of tyres influence the skid resistance. Tyre wear and grooves have an influence on water displacement, which increases skid resistance. Smooth tyres = lowered displacement of water.
Tyres with deeper grooves displace water on the road surface effectively, decreasing the possibility of skidding. There are two components of friction which develop between the tyre and road surface:
Adhesion component: Caused by the shear forces at the tyre road interface.•
Hysteresis component: Caused by the deformation of tyres when it comes in contact with the pavement.•
2.3 REMEDIES
Composition of the road surface, the application of binding agents and the effective displacement of water assist in attaining a gritty surface texture. Applying binding agents on the road surface must aim to improve stability but at some point will have a compromise between the skid resistance and generation of dust.
3. TEST PROCEDURE
We used the Skid Resistance Test Protocol for gravel roads, but were limited by the availability of test vehicles and use of the road due to continuing mining activities. Adequate tests and results were achieved given these limitations.
3.1 PROCEDUREA stretch of gravel road was selected on the main access road from the pit to conduct the tests. The chosen 1.
section was of similar structure (soil/aggregate), similar preparation (recently graded) and similar slope for each of the different surface applications.
The chosen vehicles for the tests were a Komatso 370E, CAT 773 and a Toyota LDV, to represent the vehicles 2. regularly used at the mine.
Surface preparation: 3. A. Section 1 – Normal Gravel Road: No special preparation was done on the road and serves as the Control standard for comparison.
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B. Section 2 – Water Only: Water was applied to the surface 15 minutes prior to the tests being conducted, by spraying using the normal application method with a water browser. C. Section 3 – Standard CLS (0.25% dosage): CLS was applied to this section on Monday, 19 March (to represent the standard CLS application) and again 15 minutes prior to the tests being conducted, by using the standard application method using a water browser. D. Section 4 – CLS Overdose (100% CLS solution): An undiluted 100% CLS solution was sprayed to this section 15 minutes prior to the tests being conducted.
Traffic cones were placed at each section to indicate to the driver of each vehicle to start braking at each section.4.
Each vehicle was tested at different speeds in each prepared section of road by measuring the length of the skid 5. mark on the road surface.
3.2 SAFETY
A full risk assessment was conducted prior to conducting the tests. All the necessary precautions to conduct the tests as controlled and safe as possible were taken. An ER24 emergency services unit was present for the duration of the tests. Traffic on the road was limited during the tests. All standard mine Safety Regulations was adhered to during the tests.
3.3 THIRD PARTY CONFIRMATION
Make sure an independent third party or client representative is present atoll times. This party must be familiar with this protocol and must confirm recorded test results.
3.4 EQUIPMENT
A standard distance measuring wheel was used to record the skid distances.
4. TEST RESULTS
The tests were successfully completed and yielded very informative and useful data. A definite trend was observed and an accurate conclusion can be drawn from the test results. More thorough testing should not influence or change the conclusion or result significantly, safe perhaps the percentages of differences on the different surface conditions.
4.1 TEST DATA
Date of Testing: 20 March 2012
Time: 11h45 AM
Place: Main haul road to the mining pit
Weather: Sunny & dry
Road Condition: Good. Recently graded gravel, negligible loose debris, slight down slope (less than 10º), smooth surface
Soil Calcification: Silt gravel/sand mixture
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Skid Distance (meters)
Test Vehicle & Speed Control Gravel Overdose Normal Water OnlyKomatsu 730E (5km/h) 1.2 0.6 1.3 3.7
Komatsu 730E (15km/h) 4.4 4.4 5.2 7.8
Cat 773 (20km/h) 7.5 15 20.4 23.7
Toyota LDV (20km/h) 2.4 2.5 2.5 4.5
Toyota LDV (40km/h) 11.5 11.7 12.2 14.2
Skid Distance Increase % on Control (Gravel)
Komatsu 730E (5km/h) 100% -50.00% +8.33% +208.33%
Komatsu 730E (15km/h) 100% 0.00% +18.18% +77.27%
Cat 773 (20km/h) 100% +100.00% +172.00% +216.00%
Toyota LDV (20km/h) 100% +4.17% +4.17% +87.50%
Toyota LDV (40km/h) 100% +1.74% +6.09% +23.48%
Skid Resistance against Water (% Improvement)
Komatsu 730E (5km/h) 1.2m +258.33% +200.00% 3.7m
Komatsu 730E (15km/h) 4.4m +77.27% +59.09% 7.8m
Cat 773 (20km/h) 7.5m +116.00% +44.00% 23.7m
Toyota LDV (20km/h) 2.4m +83.33% +83.33% 4.5m
Toyota LDV (40km/h) 11.5m +21.74% +17.39% 14.2m
4.1 TEST DATA
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
5. CONCLUSION
From the results, it is evident that applying water only to gravel road surfaces significantly increases the skid distance when performing emergency braking. At the different speeds and vehicles tested the “water only” road surface per-formed by far the worst. The untreated gravel surface yielded the best results but there was no significant difference between that and the overdose application of CLS. The overdose CLS in one instance actually tested better and once exactly the same as the untreated surface. Normal dosage and applications performed on average over 80% better than water and skidding distances compared to untreated gravel is not significantly further.
In our opinion: The tests showed that using only water as dust control on hauling roads significantly reduces skid resistance on all tested vehicles which reduces safety. The application of CLS suppresses the dust while binding loose debris on road surfaces and the surfactant effectively reduces water collection on the surface.
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
TECHNICAL DATA SHEET
DS-11-LB (Dust Suppressant 11 LigninBase)
DESCRIPTION:DS-11-LB Dust Suppressant is a uniquely formulated lignosulphonate-based binder and gravel preserver suitable for binding both fine and coarse particles.DS-11-LB Dust Suppressant is suitable for spray-on applications to the surface of areas requiring medium or long term dust suppression
APPLICATION RATES:Mix-in Liquid 1-2%Spray-on Liquid 1.0-1.5 kg/m 2
BENEFITS:Reduced gravel loss, dust levels and road maintenance•
Suitable for use with a variety of materials with compositions and characteristics•
Easy to apply, no specialised equipment required•
Roads can be trafficked immediately•
Environmentally friendly, non-toxic and non-hazardous•
PREPARATION:Liquid - Dilute the required DS-11-LB Dust Suppressant with the water in the water cart.
APPLICATION:Mix-in
Rip the road to 150 mm and break large clods to maximum 50 mm•
Calculate the approximate volume of water required to reach OMC and add 85% of the required product • application rate to this quantity of water
Apply the solution onto the prepared surface in 4 to 6 applications, mixing thoroughly between applications•
Shape to required camber and compact with pneumatic or vibratory roller to required density•
Apply remaining 15% product to the road surface while still damp•
Spray-onFor spray-on applications, the road surface should be well compacted, density >93%, firm and free of excess •
loose material and with sufficient camber to allow for proper drainage
Apply the product in multiple applications using a 10-15% solution of product with water•
Avoid run-off and pooling•
CHARACTERISTICS:Product form - LiquidAppearance - Brown viscous liquidSpecific gravity - Liquid -1286kg/m3pH (10% solution) - 3.5 ±1Solids % m/m - 55 ±1
HAZARDS:Fire - Non-flammableExplosion: - Non-explosiveSkin - Non-irritantIngestion - Non-hazardousEyes - Non-irritant
PRECAUTIONS:- Not applicable- Not applicable- Safety gloves are recommended- Do not ingest- Eye goggles are recommended
FIRST AID:- Not applicable- Not applicable- Rinse with water- Drink water- Flush with water
PACKAGING:Returnable IBC 1000 litre - 1286kg
STORAGE:The product is stable for several years under dry cool storage conditions
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
IDENTIFICATION OF SUBSTANCE/PRODUCT AND COMPANYProduct Name: DS-11-LB Dust SuppressantContact Details: Tel No: 087 310 2500 or +27 11 412 3059. Emergency Tel No: 082 417 1762Supplier: Nivitex Fibreglass & Resins
COMPOSITON / INFORMATION ON INGREDIENTSProduct Description: Calcium LignosulphateCASS NO: 8061 52 7 (Calcium Lignosulphate)EINECES NO: 23 25 064 (Calcium Lignosulphate)Hazardous Components: None
HAZARDS IDENTIFICATIONImportant Hazards: NoneFlammability: Non-flammableChemical Hazard: None
FIRST AID MEASURESInhalation: Remove to fresh airSkin Contact: Wash with waterEye Contact: Flush with waterIngestion: Drink water
FIRE FIGHTING MEASURESExtinguishing Media: Water, Foam or Carbon DioxideProtection of Fire-Fighters: Standard fire fighting protective clothing and respiratory mask is recommendedHazardous Decomposition Products: Sulphur Oxides, Carbon Monoxide
ACCIDENTAL RELEASE MEASURESEnvironmental Precautions: Avoid infiltration of large quantities into drains, surface water, groundwater and soil.Personal Precautions: Respiratory protection, safety goggles and rubber gloves are recommended.Spills and Clean Up: Dam area to prevent spill from spreading. Recover as much as possible of product into appropriate containers for disposal and thoroughly wash area with water.
HANDLING AND STORAGEHandling: Ensure adequate ventilation when handling. Respiratory protection, safety goggles and rubber gloves are recommended. Eye wash fountains in the work place are strongly recommended.Storage: Must be stored under dry cool conditionsIncompatible Materials: None
EXPOSURE CONTROL / PERSONAL PROTECTIONTLV (8hours): 5mg/m3Personal Protection: Respiratory-Under normal conditions in the field and in normal use the smell of the product is reported as pleasant. However, hot DS-11-LB Dust Suppressant” (.70 deg. Celsius) has been reported to have a mildly pungent aroma, which can be irritating for sensitive field workers exposed to the material at such elevated temperatures. Sensitive field workers can protect themselves by using a respirator should it be required.Skin/Hands: Not a skin irritant, but gloves recommended.Eyes: Not an eye irritant but safety goggles are required.Technical Precautions: Ensure adequate ventilation
MATERIAL SAFETY DATA SHEETMeets 91/155/EEC and ISO 11014-1PRODUCT NAME: DS-11-LB Dust Suppressant
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
PHYSICAL AND CHEMICAL PROPERTIESPhysical State: Viscous liquidColour: BrownOdour: Very slight odourpH (10%Solution): 3.5 +/- 1.0%Dry Matter: 55.00 +/- 1.0%Density (25 deg. Celsius): 1285 kg/m3Solubility: Soluble in waterSolubility in Organic solvents: Very lowPartition coefficient: Method for determination is not applicable (N-octananol/water) for this productVapour Pressure: Not applicableBoiling Point/Range: Not applicableMelting point/Range: >130 deg. CelsiusFlash Point: Not applicableExplosive Properties: Not applicableAuto ignition Temperature: >150 deg. Celsius
STABILITY AND REACTIVITYThe product is stable for several years under dry cool storage conditionsHazardous Decomposition Products: Not KnownMaterials to Avoid: Not KnownConditions to Avoid: Not Known
TOXILOGICAL INFORMATIONAcute Toxicity: LD 50: .5g/kgLocal Effects: NoneSkin Irritant: According to the OECD Guidelines No.404,1981, this product is not classified as a skin irritantEye Irritant: According to the OECD Guidelines No.404,1981, this product is not classified as a eye irritant
ECOLOGICAL INFORMATIONAquatic Toxicity - Fish: According to OECD method No 203, this product is classified as not fish toxicBiodegradability: According to OECD method No 302B, this product is classified as inherently bio gradable
DISPOSABLE CONSIDERATIONSDisposal Methods: Dispose in accordance with local/national regulations governing the disposal of waste materialsDisposal of Packaging: Residues of packaging may be incinerated unless local disposal regulations state otherwise
TRANSPORT CONSIDERATIONSRegulations: Not known regulations for this productReferences: Marpol, Annex ii, Appendix iii
REGULATORY INFORMATIONInformation: Not classified as dangerous for supply or conveyance
OTHER INFORMATIONNone
The information on this Material Safety Data Sheet corresponds to the actual level of our knowledge. This information is not product specification and cannot be a base for contractual use. The user of this product is responsible for the observation of existing laws and directives.
MATERIAL SAFETY DATA SHEETMeets 91/155/EEC and ISO 11014-1PRODUCT NAME: DS-11-LB Dust Suppressant
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DS-11-LB (Dust Suppressant 11 Lignin Base)Tel: 087 310 2500 • [email protected] • www.nivitex.com
DEMONSTRATION OF DS-11-LB Dust Suppressant INCORPORATED INTO THE ROAD SURFACE
LIMIT OF LIABILITY APPLIES
The information included in this document is given in good faith and is intended to assist you the customer in determining the suitability of this product for your application. Due to the diverse applications and conditions in which many of our products may be used, we request that you, the user, test and inspect our product to satisfy yourself of its contents and suitability for your specific need. This document does not constitute any guarantee or warranty expressed or implied. The exclusive remedy for all proven claims is replacement of our product and under no circumstances shall we be liable for any special, consequential or incidental damages.
Physical Address
12 First Street, Randfontein, 1760
Gauteng, South Africa
Postal Address
P.O. Box 2235, Randfontein, 1760
Gauteng, South Africa
Call Centre: 087 310 2500
Tel: +27 11 412 3059
Fax: 086 611 5216
E-Mail: [email protected]
Web: www.nivitex.co.za