water treatment plants process description. 2 water treatment plants process description 1.water...

WATER TREATMENT PLANTS

PROCESS DESCRIPTION

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Water Treatment PlantsPROCESS DESCRIPTION

1. Water line

2. Mud line

3. Criteria of use for Power Electronics equipments

SUMMARY

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General ProcessWATER LINE1

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WATER LINE

1. Water entry and rough-dressing

2. Elevation3. Reagents dosage4. De-sanding and Degreasing5. Primary decantation6. Biological reagents7. Clarifiers

Water Treatment PlantsPROCESS DESCRIPTION – WATER LINE

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1. WATER ENTRY AND ROUGH-DRESSING

ENTRY:Through several collectors.

LARGE OBJECTS PRE – ROUGH-DRESSINGWell of large objects with a first pre-roughdressing railing of 25cm. It is removed once a day, introducing a bivalve “spoon” and cleaning the bottom of the well.

» Water collectors

» Pre-roughdressing of large objects


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LARGE OBJECTS PRE-ROUGHDRESSING:Waste removal

TRANSPORT BANDS: Temporized action according to the elevation and descent cycle of the railings. In case of raining, the cadence is decreased increasing the frequency of elevation and descent of it.

» Large objects removal


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LARGE OBJECTS PRE-ROUGHDRESSING: It is a complement for the previous phase by means of two rough-dressing railings of 10cm.

» Large objects rough-dressing

RAKESRAKES


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ROUGH-DRESSING OF SMALL OBJECTS: Part of the previous process. Two railings of 3,5 cm.The rakes sweep out all the material, which falls on a conveyor belt. THE ELEVATION PROCESS IS MADE PREVIOUSLY. (There are Wastewater treatment plants where the elevation is made after all rough-dressings).

TRANSPORT BANDS FOR ROUGH-DRESSING OF SMALL OBJECTS: Its action depends on the elevation and descent cycle of the rakes.

RAKESRAKES

» Transport bands for small objects

» Small object rough-dressing


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2. WATER ELEVATION

» Elevation submerged pumps

In the rough-dressing processes, water is raised up to 8,28 meters height, with two complementary drives:

FIRST DRIVE:TWO SUBMERGED PUMPS

Flow = 1,2m³/seg.

Advantage = Less maintenance required than the screws (belts, bearings, …).

Disadvantage = More sensitive to obstruction


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2. WATER ELEVATION

» Screw of Archimedes

In the rough-dressing processes, water is raised up to 8,28 meters height, with two complementary drives:

SECOND DRIVE:SCREW OF ARCHIMEDES

Flow = 1,24m³/seg.

Advantage = Great elevation capacity. Immune to obstructions.

Disadvantage = High maintenance cost.


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2. WATER ELEVATION

» Elevation pump 01

In the channel there are ultrasonic probes of 6m scope to measure the height of the water surface, they measure the level. They are ultrasonic to avoid the contact with the water.

FUNCTIONING:» If the water surface goes down (decreases), then the intelligent system stops the pumps to protect them.» If the water surface goes up (increases), then the system starts them again according to the set reference.

» Elevation pump 02


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2.a. ROUGH-DRESSING EXIT AND BIFURCATION

» First flow division in the plant

FIRST FLOW DIVISION IN THE PLANT.

After the rough-dressing process the water line bifurcates symmetrically. Both circuits work equally.


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3. REAGENTS DOSAGE

» Reagent dosage centre

REAGENTS CONTROL CENTRE:

There is an automatic and centralized pumps system which allows a correct dosage of reagents.

The main object consist in helping the increase of the size and weight of certain organic particles during this phase, so that the sedimentation, which will begin in the next stage will be easier and faster. This way, the performance of the plant is optimized.

Two kind of reagents are dosed:» COAGULANTS» FLOCCULANTS


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3. REAGENTS DOSAGE

» Ferric sulphate dosage pumps

COAGULANTS DOSAGE:

It is a compound called Ferric Sulphate. It is very dense like sweet and can be stored in deposits, and it will be diluted into water to be dosed afterwards. It will be aggregated to the purifying process in first place.

» Ferric sulphate pump detail

THREE DOSAGE PUMPSTHREE DOSAGE PUMPS


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3. REAGENTS DOSAGE

» Ferric sulphate storage

COAGULANTS STORAGE:

Storage deposits don’t need to be in the control center of dosage.

» Ferric sulphate dosage

COAGULANT ADDITIONCOAGULANT ADDITION


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3. REAGENTS DOSAGE

» Polyelectrolyte dosage pumps

» Polyelectrolyte pump detail

TWO DOSAGE PUMPSTWO DOSAGE PUMPS

FLOCCULANTS DOSAGE:

It is a compound called Polyelectrolyte. It is always delivered as powder, which is diluted into water, where will remain during one hour (maturing process). Afterwards it will be dosed. It is the second one to be aggregated to the purifying process.

POLYELECTROLYTEPOLYELECTROLYTE


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4. DE-SANDING AND DEGREASING

» De-sander and de-grassing channel

» De-sander bridge detail

DE-SANDER:

It is a wide double channel with a cross carriage (similar to a crane) , which sweeps out the whole channel very slowly, so that the submerged pump attached will suction the sand of the channel.

PUMP + CARRIAGEPUMP + CARRIAGE


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» Sands dryer

» Final waste sand

SAND EXTRACTION:

The extracted sand is pressed dry in the sand classifier (there is one in each side of the channel) This is already a waste, which will be carried to an authorized wasteway.

SANDS CLASSIFIERSANDS CLASSIFIER


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» Channel sides for greases extraction

GREASING EXTRACTION:

Meanwhile the sand is extracted, the grease is separated and moved toward the sides, where a scraper will push it to the end of the channel. At the end of the channel there are two wells where this grease is collected.

» De-sander and degreasing channel

TWO SIDES PER CHANNELTWO SIDES PER CHANNEL


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» Sands dryer

» Degreaser detail

DEGREASERDEGREASER

GREASING EXTRACTION :

The grease is collected in the degreaser (one for all the channels). This waste will be carried to an authorized wasteway.


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4.a. DE-SAND EXIT AND NEW BIFURCATION

» Bifurcation of sands collector

» Detail of sands exit

SANDS EXTRACTION SANDS EXTRACTION BIFURCATIONBIFURCATION

SECOND CHANNEL DIVISION IN THE PLANT.

After the de-sander the channel bifurcates symmetrically once again. At the end of the de-sanders there are four decanters. Every circuit (four in total) works the same way.


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5. PRIMARY DECANTATION

» Primary decanter

MUD DECANTATION AND FLOATING – PARTICLES COLLECTION:

The water is distributed into 4 decanters of Ø 40m and 3m height with a capacity of 3.700m³. They are provided with a radial bridge which has scrapers in the bottom part for mud extracting and additionally it has a superficial scrapers to collect the floating-particles (surfs).


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5. PRIMARY DECANTATION

» Primary decanter detail

MUD DECANTATION AND FLOATING – PARTICLES COLLECTION :

Sweep time approximately 45. min. Water must remain 1.5 hours inside the decanter. Water enters the decanters in the middle through a baffle, which breaks the speed, and goes out through the perimeter.


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6. BIOLOGICAL REAGENTS

» Biologic reactors detail 01

TREATMENT WITH MICROORGANISM:

When water is in this stage, germs which grow up here feed themselves with all the biodegradable particles contained in the water. This germs live thanks to the oxygen, which is constantly blowed.

» Biologic reactors 01


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OXYGEN BLOWING:

Four reactors with 5.200m³ of unitary volume which are provided with four airing units as turbines of 180CV, two of them of double speed.

» Biologic reactors detail 02

» Biologic reactors 02


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» Airing units

OXYGEN BLOWING:

To keep constant the bacterium volume, it is required to control the oxygen blowing. That’s the reason for having double speed in the turbines: to control the speed depending on this parameter.

Double speed control:» SLOW SPEED» HIGH SPEED


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7. CLARIFIER

» Secondary decanter 01

SECONDARY DECANTATION:

To decant all those particles which did not sediment in the first stage, by means of the transformation suffered thanks to the biologic reactors action.

» Secondary decanter detail 01

FLOATING SURFSFLOATING SURFS


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7. CLARIFIER

» Secondary decanter 02 » Secondary decanter detail 02

SECONDARY DECANTATION :

The process is realized on four circular clarifiers with 45m of diameter and 3m height. They have a unitary volume of 4.770m³, where the biologic mud sediment, and separate from the purified water.

A part of the floating surfs escape out of the A part of the floating surfs escape out of the clarifier. This will be correct if the water conditions clarifier. This will be correct if the water conditions

are under the established limits.are under the established limits.


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7.a. WATER LINE END

» Albufera regeneration

» Coast line regeneration

PURIFIED WATER EXIT:

The purified water can follow three different process:1. Irrigation net.2. Emissary and sending to the sea. Maintenance and regeneration of the coast line.3. Third treatment and afterwards 3.1. Irrigation 3.2. Emissary and sending to the see.

PURIFIED WATER:Ready for irrigation, cultivation, Albufera maintenance.


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INDUSTRIAL WATER

» Sand filter for industrial water » Industrial water group

INDUSTRIAL WATER:

In the treatment plant there is an internal industrial water network. The water exiting from the clarifiers which goes to this industrial water system, has to go into a sand filter tank firstly and after that can incorporates to the water distribution system.


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EMISSARY

» Emissary – water to the sea 02

EMISSARY:

The water not assigned for irrigation, goes to the emissary to be pumped to the sea.

The sending of submarine water is realized by means of motors and gravidity.

» Emissary – water to the sea 01


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General ProcessMUD LINE2

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MUD LINE

1. Thickener – Floater2. Digester – Gas-meter3. Dehydration

Water Treatment PlantsPROCESS DESCRIPTION – MUD LINE

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1. THICKENER - FLOATER

MUD SEPARATION AND BIOLOGIC MUD:

Before make themselves thick, the mud must suffer a sifting process to avoid further problems in the digestion process.Installations consist of:Three thickeners based on gravidity (primary mud: diameter 27m and 3m height). Its functioning is similar to decanters functioning, the scraper sweeps the bottom instead of the surface.

MUD EXTRACTION PUMPSMUD EXTRACTION PUMPS

» Gravidity thickeners » Mud extraction pumps in thickeners


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1. THICKENER - FLOATER

MUD EXTRACTION PUMPSMUD EXTRACTION PUMPS

MUD SEPARATION AND BIOLOGIC MUD:

Before make themselves thick, the mud must suffer a sifting process to avoid further problems in the digestion process.Installations consist of:A floater (biologic mud: diameter 12,5m and 393m³ volume). In this floater air is injected in order to help the mud to float, so that can be removed by means of a superficial scraper.

» Mud floater » Mud extraction pumps in floaters


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At the end of this process we obtain two products:Treated mud: Which will suffer a dehydration process to be transformed into fertilizer.Biogas: That is a gases mix containing 65% of Methane. This gas will be employed in generating electric energy.

2. DIGESTER – GAS-METER

» Mud digester

MUD DIGESTION:

The digesters function is to produce a biochemical transformation in the mud during 21 days at 37ºC of temperature, reducing in this way the organic material around the 40%.


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3. DEHYDRATION

» Mud centrifugal machine to remove water

REAGENTS INJECTION:

Mud and polyelectrolyte are injected before realizing the centrifuging. Dosage pumps pretend to dose the maximum mud amount as possible to optimize the efficiency of the process.The polyelectrolyte must mature during 1 hour like in the water line process.

CENTRIFUGAL MACHINESCENTRIFUGAL MACHINES


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CONTACTORSCONTACTORS

HYDRAULIC - RELAYSHYDRAULIC - RELAYSVSD / SOFTSTARTERSVSD / SOFTSTARTERS

PNEUMATIC - RELAYSPNEUMATIC - RELAYSCONTACTORSCONTACTORS


VARIABLE VARIABLE SPEED SPEED DRIVESDRIVES


VARIABLE SPEED VARIABLE SPEED DRIVESDRIVES

VARIABLE VARIABLE SPEED SPEED DRIVESDRIVES

COMPLETE LINES: FLOW DIAGRAM FOR WATER AND MUD. ACTUATORS


VSD / VSD / SOFTSTARTERSSOFTSTARTERS

Water Treatment PlantsPROCESS DESCRIPTION

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Criteria of use for Power Electronics DevicesVARIABLE SPEED DRIVES & SOFTSTARTERS3

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Water Treatment PlantsCRITERIA OF USE FOR POWER ELECTRONICS DEVICES

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» TRANSPORT BANDS PRE – ROUGH-DRESSING OF LARGE OBJECTS 3kW: Contactors.» RAKES FOR ROUGH-DRESSING THE LARGE OBJECTS: Relays use. Hydraulic system.

Recommended equipments:» V2 and V5 softstarters.

[ POWER ELECTRONICS EQUIPMENTS USE JUSTIFICATION ][ POWER ELECTRONICS EQUIPMENTS USE JUSTIFICATION ]

WATER LINE – ACTUATORS FOR PRE-ROUGH-DRESSING AND ROUGH-DRESSING OF LARGE OBJECTS STAGES

This stage intend to extract the bigger residual objects to make easy keeping the flow constant.

This action is realized one per day using small powers. At first moment there are no Power Electronics devices although the softstarters means always an improvement to make the system automatic.


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» TRANSPORT BAND FOR SMALL OBJECTS ROUGH-DRESSING 3kW: Contactors.» RAKES FOR SMALL OBJECTS ROUGH-DRESSING: Relays use. Hydraulic system.



WATER LINE – ACTUATORS FOR SMALL OBJECTS ROUGH-DRESSING STAGE

This stage intend to extract the smaller residual objects to make easy keeping the flow constant.

This is an automatic operation realized increasing or decreasing the cadence depending on the requirements. At first moment there are no Power Electronics devices although the softstarters means always an improvement to make the system automatic.


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» SUBMERGED PUMPS: Variable Speed Drives.

Recommended equipments:» SD700 Series» SD450 Series

WATER LINE – ACTUATORS FOR ELEVATION STAGE

The submerged pumps try to keep the input flow constant in order to warranty a correct treatment of the water, always considering that there is no possibility of accumulating this input water.

The variable speed drive allows regulate the speed required to keep this flow constant.

Its possible to overcome problems if one of the lines is stopped or if a part of the plant is on maintenance.

The VSD allows to control the flow without stopping one of the pumps completely. The demanded flow is divided between both pumps.



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»SCREW OF ARCHIMEDES: Softstarter.

Recommended equipments:» V5 Softstarter.

WATER LINE – ACTUATORS FOR ELEVATION STAGE

The screw has a gate to regulate the flow but if the flow increases, the screw will try to elevate more water. That could provoke it to be broken.

To avoid this situation, it is possible to fix a current signal as a reference thanks to a transformer in order to protect the screw.

This system could be improved implementing a VSD controlled by this current signal.



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»THREE PUMPS FOR COAGULANTS DOSAGE: Variable Speed Drives.» TWO PUMPS FOR FLOCCULANTS DOSAGE: Variable Speed Drives.

Recommended equipments:» SD100 Series.»SD250 Series.»SD450 Series.

WATER LINE – ACTUATORS FOR REAGENTS DOSAGE STAGE

Allows to control the exact dosage of the reagents according to the results of test and analysis realized on the laboratory each hour.

Without VSD it would not be possible.

Complete control total of the dosage to treat correctly water with different quality (for example cleaner water and higher amount in summer).

Possibility of implement a closed control loop with the drives, where the reference will be a signal coming from the flowmeters. If the flow increases / decreases the dosage will be increased / decreased.



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» DE-SANDER PUMP: Contactors.» MOTOR OF DE-SANDER CARRIAGE: Contactors / reverse operation.» MOTOR FOR THE BAND OF THE SAND CLASSIFIER: Pneumatic. Relays.» MOTOR FOR GREASE SCRAPER: Pneumatic distributor.» DE-GREASER: Mechanical.


WATER LINE – ACTUATORS FOR DE-SANDING AND DE-GREASING

This stage tries to eliminate the finest sands and greases of the process.

Those actions are continuously realized. The power used is small. At first moment there are no Power Electronics devices although the softstarters means always an improvement to make the system automatic.



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» MOTOR FOR IMPULSE MUD TO DECANTATION: Contactors.» MUD PURGE: Contactors.» FLOATING SURFS ELIMINATION: Contactors.

Recommended equipments:» V2 and V5 softstarters.» SDRIVE VSD (small power)

WATER LINE – ACTUATORS FOR PRIMARY DECANTATION STAGE

To separate mud from the water to insert it on the mud line.

The mud purge is done step by step and it is a timer action. By calculating the mud amount it could be possible to use a turbidimeter and a drive to control the flow.The sweeping process is continuous, the

required power is small and the speed is fixed, for all that Power electronics softstarters could means an improvement.



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» OXYGEN BLOWING TURBINES: Softstarters.


WATER LINE – ACTUATORS FOR BIOLOGIC REACTORS STAGE

In these tanks the bacterium should be keeping alive and in an appropriate number according to the process and the analysis.

As an alternative to the softstarter a VSD could be used since it offers more regulation points.An oxygen meter could be implemented giving a signal to the drive (Xppm of oxygen dosed by the drive).



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» MOTOR FOR IMPULSION TO MUD DECANTERS: Contactors.» MUD PURGE: Contactors or Softstarter.» FLOATING SURFS ELIMINATION: Contactors.» MUD RE-CIRCULATION: Contactors.

Recommended equipments:» V2 and V5 softstarters.» SDRIVE VSD (small power)

WATER LINE – ACTUATORS IN THE SECONDARY DECANTATION

To separate the mud from the water to insert it on the mud treatment line. A part of it goes directly to the biologic tanks to keep the bacterium number in accordance to the requirements.

The mud purge is done step by step and it is a timer action. By calculating the mud amount it could be possible to use a turbidimeter and a drive to control the flow.The re-circulation is continuous and the volume is high (1300m³/h).

The sweeping process is continuous, the power required is small and the speed is fixed, for those reasons Power electronics softstarters could means an improvement.



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» MOTOR FOR INDUSTRIAL NET PUMPS: 1 VSD + 2 Softstarters.» MOTOR FOR IRRIGATION NET PUMPS: Variable Speed Drives.

Recommended equipments:» SD700 Series» SD450 Series» V5 Softstarter

WATER LINEACTUATORS FOR PRESSURE GROUP – INDUSTRIAL NET – IRRIGATION NET

Typical pumping control application.

It intends to control the pressure on the internal distribution system of industrial water. The irrigation of the whole plant is also controlled by VSD.

Versatile and flexible:

The control is done by the drive. In case of a fault, the PLC will take the control over the softstarters.



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» MOTORS OF THE EMISSARY: 1 VSD + 2 Softstarters + Contactors.

Recommended equipments:» SD700 Series» V5 Softstarters

WATER LINE – ACTUATORS OF EMISSARY

Pumping control application where there is so much flow and the height is small. The pumps go out of the curve easily and the consumption increases excessively.

Here is needed a startings number optimizing (the rest of the process to lead the water to the sea is done by gravidity).

Equipment regulation allows to start the pump only 1 or 2 times per day, saving around 24.000€/month.



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» MOTOR FOR BOTTOM SCRAPER: Contactors.» MUD EXTRACTION PUMPS: Softstarter or Variable Speed Drives.

Recommended equipments:» SD700 Series» V5 Softstarters

MUD LINE – ACTUATORS FOR THICKENERS

Once the mud is collected and has to be sent to the digester, it is convenient that the additions are as homogeneous as possible.

We get a great help from the drive in this dosage.

In this stage we pretend to optimize the startings to avoid the mud hammer because due to the mud density, the pipes of the installation could be seriously damaged.Distances to the digester are big and the column of mud to be supported is high.



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» MOTOR OF SUPERFICIAL SCRAPER: Variable Speed Drive.» MUD EXTRACTION PUMPS: Softstarter or Variable Speed Drives.» PRESSURIZING PUMPS : Softstarter.

Recommended equipments:» SD700 Series» V5 Softstarter

MUD LINE – ACTUATORS FOR FLOATER

The superficial mud varies continuously.

To keep the sweeping constant a variable speed drive is use, to set the system according to the current mud amount.

In this stage we pretend to optimize the startings to avoid the mud hammer because due to the mud density, the pipes of the installation could be seriously damaged.Distances to the digester are big and the column of mud to be supported is high.



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» MUD MOVEMENT PUMPS: Softstarter or Star – Delta contactor.

Recommended equipments:» V5 Softstarter.

MUD LINE – ACTUATORS FOR DIGESTER – GAS-METER STAGE

In this stage the material is reduced and as a secondary effect a gas generation is produced. This gas is used in the cogeneration plant.

The pipes are suffering considerably. Using a softstarter this situation will be improved.

The pumps that move the mud stop two times per day for cleaning process. Each time a new start occurs will appear the “mud hammer” problem.



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» DOSAGE PUMPS FOR MUD AND REAGENTS: Variable Speed Drives.» CENTRIFUGAL MACHINES: Variable Speed Drives.

Recommended equipments:» SD700 Series» SD450 Series

MUD LINE – ACTUATORS FOR DEHYDRATION STAGE

The pumps that realize the dosage must be set at several reference points. Depending on the realized tests, it should be possible to calculate the reagent dose.

Without drives this process could not be realized.

The starting of the centrifugal machines requires a huge inertia moment. That implies to apply a starting ramp very long (3 – 4min).

Only the VSD can offer this warranty.



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EXAMPLE: In = 150ASelected Frame = 210AMaximum Torque = 1,5TnImax = 1,5x210 = 310A

MOTOR TORQUE CURVES

Relation Tmax/Tn310 / 150 = 2,1Tn

[ BACK TO ELEVATION ][ BACK TO ELEVATION ]


Thanks for your attention

PresentationWATER TREATMENT PLANT: Process description

RealizedPilar Navarro

OrganizedMarketing Department

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