solid waste evolution and concepts p… · 50 = 30 + solid waste + 1 total amount of generated...
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Section II Solid Waste Management – Waste Management
Liquid and solid Waste (0670545)
Very Important Note: Most of the figures and tables are downloaded from google
and various text books
Solid Waste Evolution and Concepts:
- Since the beginning of humanity, both humans and animals have been using earth
resources to support their life. As a result of these activities, waste is being
produced.
- At small community No waste problem, but when people starts live in bigger
communities (city) more waste produced ...... thus the demand for waste
management (WM) appear.
- Heterogeneous nature of commingled solid waste makes studying it not an easy job
What is waste:
- The term solid waste refers to thrown items that have no value for its owner
even though it may consider as a material or heat resources for other users.
Why we need to manage the solid waste (SW)?
- The relationship between public health and the improper waste storage, handling
and disposing is significant.
- Improper WM leads to suffer from rats and flies breeding and epidemic diseases.
- Reduce the pollution form waste and its emissions like Methane (CH4), hydrogen
sulphide (H2S), CO
- Protect ground water from leachate (العصارة)
Section II Solid Waste Management – Waste Management
Waste Classifications:
1- Classification in dependent on waste physical status
a- Solid
b- liquid
c- gas
2- classification based on waste nature:
a- hazardous waste: that has one of the hazardous characteristics that pose
human and environmental risks
b- non-hazardous waste
c- Medical waste
d- Special waste like tires, car batteries (acid lead) , used oil
HW# what are the
hazardous
characteristics??
Section II Solid Waste Management – Waste Management
3- Classification in dependent to wastegeneration source to the following:
a) Residential or Domestic waste:includes non-hazardous waste generated in
households,
It includes commercial,business establishments and institutions that has
same composition.
b) Commercial: all municipal solid waste generated from business
establishments such as stores, markets, office buildings, restaurants and
shopping centers.
c) Institutional: waste originating in universities, schools, hospitals, prisons,
research centers and other public buildings.
Note: since the commercial and institutional wastes are generated from
people activities thus its composition almost same as the domestic
d) Industrial:
- Heterogeneous mixture of different materials generated during an industrial
process.
- -It may be gaseous, liquid, sludge, or solid.
- -It's composition depends upon the natural resources, raw materials, markets,
and manufacturing process.
Section II Solid Waste Management – Waste Management
e-Agricultural:
- The solid waste resulted from plant cultivation activities such trees trimming
waste, grass, plastic house, and irrigation hoses.
f- Construction and Demolition:
- All solid waste generated from construction activities, dredging materials,
rubble (انقاض) resulting from construction, demolition of homes, and other
structures or pavements.
- The nature of this type of SW depends upon the used resources in a given
region or country for the purposes of construction.
g- Municipal Services:
- Street sweeping (cleaning), landscaping, parks and beaches
Section II Solid Waste Management – Waste Management
Organics (food waste), 48.9
Paper & Cardboard, 13.
3
Plastics, 15.2
Textile, 5.8
Rubber & Leather, 2.6
Metals, 3.1
Glass, 3.8
Miscellaneous,7.3
h-Treatment plant sites: such as sludge
I –Special waste: such as car tiers, consumer electronic and white goods (refrigerator,
washing machines), used oil.
Composition of Solid Waste
It’s the term used to describe the individual components that is included within a solid
waste stream and their relative distribution usually based on percentage by weight.
Waste composition in zarqa city (almost same as Jordanian waste composition)
Section II Solid Waste Management – Waste Management
- Waste composition is vary through the time due to changes in consumption
trend and life style.
- Waste composition is vary from one place to another
Main Components of SWComposition for Different Studies and time periods.
RSS
(1994 )
Fichtner
( 1996 )
CMCE
(2002 )
JUST
(2007 )
MoEnv. and RSS
(2009)
Study
Composition %by Weight
53.0 44.0 51.4 52.2 38.8 Organics
17.0 10.6 12.6 12.7 12.2 Paper and Cardboard
8.0 2.4 3.1 1.4 3.8 Metals
12.0 13.2 14.2 17.1 17.1 Plastics
10.0 1.4 1.8 2.5 2.6 Glass
- 4.7 4.2 - 8.5 Textile
- - 3.0 - 1.5 Rubber and Leather
- - 0.1 - 0.1 Hazardous waste
0.0 23.6 9.6 14.1 15.4 Miscellaneous
Ministry of Environment, (2009)
Section II Solid Waste Management – Waste Management
Comparison of Jordanian Solid Waste Contents with other Countries.
Waste
Composition
Jordan Asian
Countries
UK USA
Organic 50-68 75 36 20
Paper 5-10 2 31.2 43
Metal 3-6 0.1 5.3 7
glass 2-5 0.2 3.8 9
Plastic 4-6 0.1 5.2 5
Al-Ansari A. et al. (2005)
Example:
a family brings approximately 50 kg of consumer good a week (food,magazine ,
appliances…) of this amount 60% is consumed as food . half of the food is used for
biological maintenance and ultimately released as CO2 and the reminder is discharged
to sewer. The green recycle is about 25% of the solid waste that is generated.
Approximately 1kg is accumulated at home. Estimate the solid waste amount that
placed at curb each week??
Main equation:
Accumulation = input – output
consumer good food
(input)
Solid waste
Accumulation
Section II Solid Waste Management – Waste Management
Consumed food = 0.6 * 50 = 30 kg
Input = output (food) + output (solid waste) + accumulation
50 = 30 + solid waste + 1 total amount of generated solid waste = 19 kg
25% of the solid waste is recycled = 0.25 * 19 = 4.75 kg is recycled
Thus the solid waste send to curb side collection weekly = 19- 4.75 = 14.25 kg.
Characteristics of Solid Waste
- It is the identification of chemical,physical and biological properties of waste.
- Characterization is limited to residential, commercial and some industrial waste.
- It is difficult process due to the limited number of samples, that can be collected
and analyzed, the large number of sources and the heterogeneous nature of
solid.
1- Physical Properties of Solid Waste The main physical prosperities of solid waste are: specific weight, moisture content,
particle size, size distribution and field capacity.
I. Specific weight:
- The weight of materials per unit volume lb/yd3 or kg/m3.
- Each waste component has its own specific weight.
- Compaction process can affect the specific weight, so the specific weight is
reported for uncompacted waste or as found in the container.
- Typical value of specific weight for delivered solid waste in compactor is
296.6 kg/m3(500 lb/yd
3) (Tchobanoglous, et al., 1993).
II. Moisture content:
- Represents the amount of water in the waste.
- This is considered the major parameter in measuring the heat value of the solid
waste, as the moisture content is higher; the lower is the heat or calorific value
of the solid waste.
Section II Solid Waste Management – Waste Management
- Moisture content is measured as the difference in weight for an item wet and
after dried in an oven at 105 oC.
- The typical data for the moisture content is between 15-50%.
-
Section II Solid Waste Management – Waste Management
III. Particle size and size distribution:
- It is an essential term in material recovery especially with mechanical sorting
machines like screens or magnetic separator.
- The average size for individual solid waste components is between 17 -20 cm
(7 -8 inches).
IV. Field capacity:
- It is the total amount of moisture that can be retained in a waste sample subject
to the downward pull of gravity.
- It is important to determine the leachate formation in the landfill (Vesilind et
al., 2002).
2- Chemical Properties of Solid Waste
- It is essential to design processing and recovery options, especially heat recovery.
The main chemical prosperities are ultimate and proximate analysis, fusing point
of ash and energy content.
a) Proximate analysis:
- The determination of the combustible components in solid waste. It includes
moisture content, volatile combustible matter, fixed carbon and ash (Vesilind
et al., 2002).
Section II Solid Waste Management – Waste Management
b) Fusing point of ash:
- The temperature at which ash resulting from the burning of waste at 1100 –
1200 oC (Tchobanoglous, et al., 1993).
c) Ultimate analysis of solid waste:
- The determination of the percentage of Carbon, Nitrogen, Oxygen, Hydrogen,
Sulfur, and Ash.
- Ultimate analysis is used to characterize the chemical composition of the
organic matter in municipal solid waste.
- Determining chemical composition is necessary to achieve the optimum C/N in the
composting treatment of solid waste, or to calculate the heat content (Vesilind et al.,
2002).
Section II Solid Waste Management – Waste Management
d) Energy content of solid waste:
- It is determined by full scale boiler as colorimeter and laboratory bomb
colorimeter or by calculations if the elemental composition is known.
- The moisture content directly affects the energy content ?? why
because portion of the heat within the solid waste will be
consumed to evaporate the moisture. be determined.
KJ/kg or K calori/kg
Average Jordan energy content: 2747 kcal/kg
Section II Solid Waste Management – Waste Management
3- Biological Properties of Solid Waste
- Include the content of the organic fractions in the solid waste except the
plastic, rubber and leather components.
- The main organic fractions are the oil, fat, water soluble substances as sugar
and starch, cellulose, lignin and protein.
- Usually the organic fraction is degradable even though some fractions may
take long time to degrade as lignin (Vesilind et al., 2002).
- Biodegradability of the organic fraction of the solid waste is determined by the
volatile solid content (VS) that is determined at a temperature of 550 oC.
- Degradation of the organic fraction is responsible for most of the odor
produced from the solid waste degradations (Tchobanoglous, et al., 1993).