Of - environmentclearance.nic.inenvironmentclearance.nic.in/writereaddata/FormB/EC/EIA_EMP/...for Refined Sugar manufacturing unit and Gas turbine based power plant of capacities 3000

0

ENVIRONMENTAL MANAGEMENT PLAN

FOR

PROPOSED 170 TPH COAL FIRED BOILER

Of

M/s. SILKROAD SUGAR PVT LTD. VAKALAPUDI VILLAGE,

KAKINADA RURAL, EAST GODAVARI Dt.,

ANDHRA PRADESH.

PREPARED BY

SV ENVIRO LABS & CONSULTANTS

Environmental engineers & consultants in pollution control

Head Office Branch Office

H.No. 38-19-44/2/2&3, H.No. 2-53,

Jyothi Nagar, Mahipala Street,

Marripalem, Yanam – 533 464.

Visakhapatnam – 18. Phone: 0884-321528

Cell: 0891-2797377. Cell : 94403 38628

1

CHAPTER-I

INTRODUCTION

2

1.1 INTRODUCTION

M/s. SILKROAD Sugar Private Limited is situated at Vakalapudi village, Kakinada Rural in

East Godavari District, Andhra Pradesh. The integrated industrial complex includes facilities

for Refined Sugar manufacturing unit and Gas turbine based power plant of capacities 3000

TPD and 35 MW respectively. These units were commissioned during Aug-2010.

M/s. SILKROAD Sugar Pvt. Ltd., was given allocation of 1,00,000/- SCMD of natural gas

against the requirement of 3,50,000/-SCMD. With this allocation only 3 to 3.5 MW of power

is being generated and from the exhaust gases 25 TPH of steam generated form the HRSG.

Due to this lower steam availability the Sugar Refinery is being operated at 500TPD capacity

as against the designed capacity of 3,000 TPD.

In order to meet the full efficiency and the installed capacities and to generate licensed

products, it is un-avoidable for the unit to go for the installation of total 170 TPH (90 + 80 )

capacity boilers which will run on coal based (Indian and Imported coal) as the gas supply is

not available fully. This proposed system will be a fallback arrangement for the existing gas

turbine and Heat Recovery Steam Generator (HRSG).

3

DETAILS ABOUT THE PROJECT SITE

M/s. SILKROAD Sugar Private Limited is situated at Vakalapudi village, Kakinada Rural in

East Godavari District, Andhra Pradesh and the proposed installation of 1 x 90 TPH and 1X

80 TPH boilers will be within the premises only to meet licensed production.

Details about Project Site as per table:

Longitude 820 15’ 36’’ E

Latitude 160 59’ 29’’ N

Annual rainfall 1080 mm

Min and max temp. 220C and 470 C

Avg. relative humidity 75 %

Avg. wind speed 10-12 KMPH

Predominant wind direction

Summer

Winter

Monsoon

SE

NE & NW

SE & S

Nearest highway NH – 214 & NH - 5

Nearest railway station Kakinada Port

Nearest human settlement Vakalapudi

Nearest town Kakinada

Nearest seaport Kakinada

Nearest river Godavari

Nearest reserved forest None with in 10 km

Nearest National park None with in 10 km

Historical places None with in 10 km

Nearest barrage None with in 10 km

Nearest hills None with in 10 km

4

5

1.2 DETAILS OF PRESENT PROPOSAL

Installation of 90 TPH boilers - 1 nos

Installation of 80 TPH boilers - 1 nos

Installation of chimneys - 1 nos

Total Co-generation power - 16 MW (through two steam turbines)

1.3 EXISTING PRODUCTS

Refined Sugar - 3000 TPD

Co-generation power - 35 MW

Molasses - 55 TPD

1.4 List of Existing Raw materials and Chemicals.

Sl.No Description As per CFE for

3000 TPD

1 Raw Sugar 3070 TPD

2 Lime 1000 Kgs / day

3 Phosphoric Acid 1400 Kgs/day

4 Flocculent 45 Kgs/day

5 Colour Precipitant 900 Kgs/day

1.5 FRESH WATER CONSUMPTION DETAILS

S.No. Description Existing

Quantity – 130

TPH BOILER

(GAS BASED)

Proposed

Quantity – 170

TPH BOILER

(COAL BASED)

1. Process & Wash 510.8 510.8

2. Boiler makeup 92.5 285.0

3. Cooling tower 1307.1 1465.0

6

4. Domestic 12.0 10.0

TOTAL (KLD) 1922.4 2270.8

1.6 WASTE WATER GENERATION

S.No. Description Existing Quantity

– 130 TPH

BOILER (KLD)

Proposed Quantity

– 170 TPH

BOILER (KLD)

1. Process & Wash 492.30 492.30

2. Boiler blow down 64.80 84.24

3. Cooling tower blow

down & WTP effluent

360.00 397.44

4. Domestic 9.00 3.00

TOTAL 926.10 976.98

DETAILS OF ADDITIONAL WATER USAGE & DISPOSAL FOR THE PROPOSED SYSTEM

WASTE WATER TREATMENT SCHEME AND BIFURCATION

S.No. Description QUANTITY (KLD)

1. Total waste water 973.98

2. FEED TO RO 974.00

3. RO TO PROCESS (for reuse) 780.00

4. RO REJECTS 194.00

5 RO REJECTS TO MEE 194.00

S.No. Description Proposed Quantity –

170 TPH Boiler (KLD)

1. Additional water used for boiler makeup 192.10

2. Additional water used for cooling tower makeup 158.40

TOTAL 350.50

3. Water lost as vapour through cooling tower and

steam/condensate circuit

293.62

4. Additional water sent to ETP 56.88

Total 350.50

7

6 MEE CONDENSATE TO COOLING TOWER 176.00

7 AT FD DRY PRODUCT 4.00

8 PROCESS LOSS 2%

TOTAL RECYCLING OF WATER FROM TREATMENT SYSTEM

S.No. Description Proposed Quantity – 170

TPH Boiler (KLD)

1. RO PLANT 780

2. MEE CONDENSATE 176

TOTAL 956

3. TOTAL COOLING TOWER MAKE UP &

FLY ASH/ COAL SUPPRESSION FROM

RO PERMEATE & MEE CONDENSATE

956

TOTAL 956

COMPARISON OF POLLUTION LOAD IN THE EXISTING AND PROPOSED SCHEME

Sl.No Description Unit of

Measure

Existing

system

Proposed coal fired boiler

system *

1 Capacity of Boiler TPH 130 170 (90 + 80)

2 Fuel Natural Gas Mixture of Indian and

Imported coal

3 Type of Turbine Gas turbine Steam Turbine

4 Capacity of Turbine MW 35 16

5 Fuel requirement Unit / Hr 13000 Std

M3/Hr

32.966 Mts/Hr

6 Boiler make up water

requirement

Kl/day 92.5 284.64

7 Boiler blow down

water

Kl/day 64.8 84.24

8 Rate of flue gas going

out of chimney

Nm3/Hr 636228 168225

9 Suspended Particulate

Matter in the flue gas

Mg/Nm3 < 50 < 50

10 Sulpher Dioxide in the

flue gas

Mg/Nm3 1-2 1400

11 Nitrous Oxide in the

flue gas

mg/Nm3 10-20 250

12 Exhaust gas

temperature

Deg C 120 145

13 Quantity of Ash

generated

Tons/day Nil 229.4

14 Auxiliary Cooling

water requirement

Kl/day Nil 158.4

15 Auxiliary Cooling

tower blow down

Kl/day Nil 37.44

8

Note: * Proposed coal fired boiler system is designed for 100% fall back to the existing

gas fuel system. Same will be operated along with the existing system to the extent of

shortage in gas supply to meet steam requirement for 3000 TPD sugar refining.

9

CHAPER-II

PROCESS DESCRIPTION

2.0 PROCESS DESCRIPTION

Power Plant

To meet the power and steam requirement of the refinery, a 35 MW (42.1MW ISO rating)

gas based power plant is installed. The power requirement of the refinery is about 8 MW and

the balance power generated is exported to the state power grid. The steam produced from

the flue gasses, about 130t/hr, is used in the process.

SUGAR REFINERY

Raw Material:

Raw material for the refinery is Raw sugar imported with the colour level of 900 to 1200

ICU, regulated % of moisture, non sugar and other components present in it.

10

Melting:

The raw sugar is charged into floor level conveyors using dumpers which carry the sugar to

melter. Here the sugar is mixed with water, usually sweet water recycled from the process

and a raw sugar solution of about 65 brix is prepared. Heating is applied to aid dissolution

and the temperature at the outlet of the melter is about 80 deg C. Colour precipitant is added

to precipitate the colouring matter to the possible extent in clarifier.

Clarification:

Phosphatation and deep bed filtration: This process is carried out in continuous clarifiers to

partially remove coloured impurities from sugar. Lime and phosphoric acid are added to the

melt along with flocculants which results in calcium phosphate scum formation which carries

by occlusion a substantial part of the colouring matter in sugar.

The scum is separated by floatation and washed in a 3 stage scum de-sweetening system to

remove the sugar content, dewatered and separated in a filter press. This calcium phosphate

has higher nutrient value and can be used as manure.

The clarified liquor contains some scum from the clarifier stage and is filtered in a deep bed

filter which is packed with sand, gravel and anthracite to get clear scum free liquor. The filter

is backwashed with filtered melt from time to time to remove the scum accumulated in the

bed.

Ion Exchange:

The clear liquor is then passed through ion exchange columns which contain a bed of acrylic

and styrene polymer based resins which adsorb the colouring matter in sugar solution. The

liquor coming out of the bed is substantially decolourised and is ready for concentration.

The ion exchange beds are regenerated from time to time, when the adsorption capacity is

exhausted, using an alkaline brine solution.

The decolourised liquor is filtered through fine filter to remove any suspended matter and

sent for evaporation.

11

The alkaline brine which is used for regeneration of the ion exchange resins is passed

through membrane filters to separate the excess brine for recycle. The retentate from the

membrane filters which contains the colouring matter from sugar is sent to Multiple Effect

Evaporator for concentration and mixed with Molasses.

Evaporation:

The decolourised liquor is concentrated in a triple effect evaporator from a concentration of

63 brix to 72 brix prior to pan boiling.

Pan Boiling and crystallization:

The concentrated liquor is boiled in a series of vacuum pans to a brix of 88 to 90 with

seeding to crystallize the sugar in solution. The massecuite is transferred to crystallisers

before feeding to centrifugals.

Depending on the quality of product desired, the molasses is boiled 3 or 4 times in

subsequent stages to get progressively darker coloured product.

After the 4th boiling the molasses is sent to the recovery section to recover the residual sugar

before sending the final molasses out.

Centrifugation:

The massecuite in each stage is filtered in basket centrifuges to separate molasses from the

crystals as well as washing the crystals. The crystals vary in colour depending on which stage

the massecuite is from.

The crystals are discharged batch wise from the bottom of the centrifuge to a hopper for

feeding to the dryer.

Dryer

12

The wet sugar is passed through a rotary dryer to remove the residual moisture content in the

sugar. The dryer is a long, cylindrical drum with slight inclination, rotating on rollers, Hot air

is passed from one side and wet sugar from the other. The sugar is discharged from the other

end dry.

Storage and packing

The dry sugar from the dryer is sent to silos for intermediate storage through a grader where

over size and under size crystals are removed. Several silos are provided to store sugar of

different quality.

Depending on the market requirement different grades of sugar are blended in a blender and

packed in bags of different sizes and sent to the refined sugar warehouse for export.

Recovery section:

The molasses from the pan station still contains some high purity sugar. This is recovered in

recovery pans as dark coloured sugar which is sent to the melting station for reprocessing.

Sugar from excess sweet water is also recovered in this section.

PROCESS LAY OUT-Existing

The process of refined sugar manufacture can be divided into the following sections and the

schematic diagram of refined sugar manufacturing is presented below.

1. Raw Sugar unloading

2. Melting

3. Phosphatation and Filtration

4. Ion Exchange

5. Evaporation

6. Pan boiling and crystallization

7. Centrifugation

8. Drying

9. Storage and packing

10. Recovery section

Raw sugar - 3070 ton per day

Melting

Water

13

PROCESS DEISCRIPTION FOR PROPOSED 170 TPH COAL FIRED BOILER

The major equipments of the plant are

a. Boilers

b. Electrostatic precipitator

c. Turbo generators

d. Coal storage

e. Coal handling system

f. Ash handling system

g. Ash storage

h. Cooling water system

14

Coal receipt and storage system

Coal is used as fuel in the boiler to generate steam. Coal will be brought to the plant

by trucks and unloaded in a closed storage yard, which can accommodate coal of about

15days requirement.

Coal crusher

Coal will be reclaimed using front end loaders/dozers. Coal will be fed to ground

hoppers. The raw coal size will range from 150mm to 50mm; however, the size of coal

required for boiler will be 6mm. Hence, the coal will be sized in a crusher and sieved in a

screen. Coal, after crushing and screening, will be stored in the bunkers installed in front of

the boilers.

Boiler

When coal is fired in the boiler, the heat released will be utilised to convert water into

steam at high pressure and temperature.

Turbine

The steam thus produced will be fed to the turbine, where the thermal energy is

converted into mechanical energy. The turbine will be coupled to a generator through a gear

box, where the mechanical energy will be converted in to electrical energy.

Ash Collection

After burning, the mineral matter/ash will be taken away from the boiler through hoppers

provided in the bed zone, economiser, air preheater and electro static precipitators. The ash

will be conveyed to a storage bin pneumatically through steel pipes.

Electrostatic Precipitator

The solid particulate matter in the flue gas will be removed using electro static precipitators.

The outlet dust concentration will be maintained at 50mg/Nm³.

The plant will have other systems like

a. Cooling tower

b. Cooling water pumps

c. Air compressors

d. Electrical system for evacuating the power produced

15

Electro static precipitator:

The flue gases coming out of the boiler will be having high dust concentration and will be

passed through an electrostatic precipitator to capture the dust. Each boiler will have one ESP

at the back end.

The electro static precipitator will have emitting electrodes and collecting electrodes. There

will be transformer rectifiers in each filed to create the ionisation. Each filed of ESP will

have on hopper at the bottom to collect the ash.

Technical data:

Type of precipitator Electrostatic precipitator

Inlet dust concentration g/Nm³ 63 (for worst coal)

Outlet dust concentration mg/Nm³ 50

Specific collection area m²/m³/sec Approx 100

No of fileds 4

Collection efficiency % 99.92%

Dust suppression systems

The dust generated in the coal yard will be controlled by providing dust suppression system

using water nozzles. The dust emanating from the transfer points of conveyors and crusher

house will be extracted using suction blowers; the dust laden air will be filtered in a bag

filter. The dust thus collected will be fed back to the system. The air escaped from the filter

will be evacuated to the atmosphere through a separate stack.

Specification of coal proposed to be used

Sl.No Fuel Composition (% by

Weight)

Indian coal Imported coal

01 C 34.43 42.85

02 H2 2.25 3.48

03 N2 0.76 0.86

04 S 0.04 0.6

05 H2O 10 35

06 ASH 40 8

07 O2 12.52 8.91

07 GCV of fuel (K cal/kg) 3200 4500

16

PROCESS FLOW DIAGRAM – 170 TPH BOILER

COAL STORGAE

COAL CRUSHER

COAL STORAGE BUNKER

BOILER

ASH

STORAGE SILO

COVERED TRUCKS TO DISPOSAL CEMENT

PLANT/BRICK MANUFACTURING

CHIMNEY ESP

VENT BAG FILTER

17

CHAPTER-III

ENVIRONMENTAL MANAGEMENT PLAN

18

3.0 ENVIRONMENTAL MANAGEMENT PLAN

Any type of development project exerts certain benefits and adverse impacts on the

surroundings.

Environmental Management Plan includes protection/mitigation/enhancement measures as

well as suggesting post project monitoring programme. Environmental management plan

may often suggest additional project operations that have to be incorporated in the

conventional operation.

The Environment Management Plan (EMP) is required to ensure sustainable development in

the study area of the proposed plant site, hence it needs to be all encompassive plan for which

the proposed industry, Government, regulating agencies like pollution control board working

in the region

The management action plan aims at controlling pollution at the source level to the possible

extent with the available and affordable technology followed by treatment measures before

they are discharged.

Environmental management plan aims at the preservation of ecosystem by considering the

pollution abatement facilities at the plant inception. In Silkroad Sugar pvt. Ltd., pollution

abatement has become an integral part of planning and designs along with techno economic

factors.

19

3.1 WASTE WATER GENERATION SOURCES AND

TREATMENT SYSTEM

Cogeneration Power Plant-existing

The quantity of wastewater from various sources and their expected characteristics are as

given below:

WATER TREATMENT Plant Effluent: In the water treatment plant, filters have to

be periodically back washed and rinsed. Some water gets consumed in this process

and effluents get created. The wastewater generated from this plant as WATER

TREATMENT plant. There will be some reject water from water treatment plant

clarifier(ACTIFLOO). The effluents would include impurities generated during back

wash and the above reject water from clarifier. The main parameter critical in

WATER TREATMENT plant effluents is high TDS, pH, Sulphates and Chlorides.

Boiler Blow down (B/B-DN): The second source of effluents would be the boiler

blow down. In the boiler steam is produced by circulation of aerated water from

WATER TREATMENT plant. As more and more steam gets evaporated, the

dissolved impurities get concentrated and have to be periodically removed, by

blowing down water from the boiler drum. Loss due to this blow down is made up

from the WATER TREATMENT system.

Cooling tower Blow down (CT/B-DN): Periodic continuous blow down from

cooling tower is essential to maintain the water chemistry required for condensing the

steam in turbine condensate. The cooling tower blow down would contain high TDS,

Alkalinity, Turbidity, Hardness, and high pH ranging above 8.

Plant Washings: The plant units would be washed for removal of impurities etc. the

typical reagents used are HCL, caustic lye, etc.,

Stack scrubber water: The scrubbing (if taken up) for removal of particulates fly

ash would add.

Sugar Industry-existing

The process and washings water from sugar processing.

20

Water input and Effluent generation. - EXISTING

Fresh water is received from Godavari River’s summer storage tank at Samalkot

through pipeline @ 0.5 MGD

In the following table, Point of usage of fresh water and points of waste water

generation & loss of water are given

Waste water generated from the process and utility blow downs are treated in effluent

treatment plant and are further purified in a Reverse Osmosis plant. The permeate of

RO plant is recycled to cooling tower for make up.

RO reject is concentrated in a Multiple Effect Evaporator and waste is obtained as salt.

The water evaporated is condensed and taken into the cooling tower as make up water.

WATER BALANCE- EXISTING

All figures in KLPD

Input

As Per CFO

Output

As Per CFO

3000 TPD 3000 TPD

Process & Washings 510.80

Process Effluent 492.30

Water in molasses and solid waste 11.50

7.00

Boiler 92.50 Boiler Blow down 64.80

Loss 27.70

Cooling Tower 1307.10 Cooling Tower Blow down 360.00

Loss 1847.40

Domestic 12.00 Domestic Effluent 9.00

Loss 3.00

Water from

Godavari

1920.40

Water through

Recycled stream

(through both ETP

RO permeate and

MEE condensate)

900.30

Total water input 2820.70 Total Output 2822.70

Note: Actual raw water consumption : 1922.40 KLD

Treated waste water recycled into process : 900.30 KLD

Total water consumption : 2822.70 KLD

21

WATER BALANCE INCLUDING THE PROPOSED COAL FIRED BOILER

SYSTEM

WATER BALANCE (KLPD) PROPOSED

Input As Per

CFO

Output As Per CFO

Process & Washings 510.8 Process Effluent 492.3

Water in molasses

and solid waste

18.5

Boiler 284.6 Boiler Blow down 84.24

Loss 200.36

Cooling Tower 1465.5 Cooling Tower

Blow down

397.44

Loss 2024.06

Domestic 13 Domestic Effluent 10

Loss 3

Water from Godavari 2273.9

water through Recycled

stream (through both

ETP RO permeate and

MEE condensate)

956

Total water input 3229.9 Total Output 3229.9

22

WASTE WATER TREATMENT

The wastewater generated is highly organic and hence is amenable to biological treatment.

The wastewater is first sent to bar screen to remove suspended solids. Then equalization of

the wastewater is done to reduce the shock loads on the treatment system.

Then the wastewater sent to primary settling tank to remove settable suspended solids after

treatment the wastewater is treated biologically by activated sludge process to reduce the

BOD and COD load in the effluent. The wastewater after secondary treatment is sent to

tertiary treatment after the treatment effluent sent to green belt development. The sludge

generated from the treatment system is dewatered on Sludge drying beds and will be used for

green belt development.

Water Pollution

The contribution of effluent from process plant is from Ion Exchange wastewater, plant

washings from process, utility blow downs and from domestic facilities. The effluent

treatment plant is designed to have a zero liquid discharge consisting of MBR (Membrane

Bioreactor) system, Reverse osmosis (RO), Multiple effect evaporator to concentrate the

rejects from RO and Agitated thin film dryer (ATFD). Permeate from the RO and the

condensate from multiple effects Evaporator is reused for cooling tower makeup.

The water balance of the plant with the addition of MBR, RO and MEE system is as follows:

Total Effluent Generation and Characteristics

Type of Effluent Quantity, KLD Characteristics

Process Effluent 492.30 PH : 7.5, BOD : 2200 mg/l

COD : 3500 mg/l

Utility Blow downs 433.80 pH: 7 – 8, TDS : 4000 mg/l

TSS : 200 mg/l

23

Effluent Treatment System

The effluent treatment and treated effluent handling are as described below.

The effluents from the plant is divided into 2 streams

1. Process effluent of 492.30 m3/day containing BOD of 2200 mg/L and COD of 3500

mg/L

2. Utility Effluent consisting of Boiler blow down and Cooling Tower blow down of

433.80 m3/day

Process Effluent Treatment

The Process effluent is collected in an Equalisation Tank in order to homogenize the feed to

the following stages and pumped to a Bar Screen Chamber to remove the floating impurities

followed by Neutralisation tank for pH adjustment.

The neutralised effluent is pumped to the aeration tank where biological treatment is done

using activated sludge. In the aeration tank the micro-organisms present in suspended form

oxidise the dissolved organic content of the waster water. The MLSS is maintained at 4000

ppm.

After primary treatment the effluent is pumped in to MBR stream where the secondary

treatment starts with 8000 – 12000mg/l of MLSS and constant air flow through air blower.

During the process COD, BOD levels are further reduced. When BOD and COD are reduced

to desired levels, the water is filtered through the MBR membrane filter by suction pump and

transferred to the RO feed tank. Excess sludge is sent back to sludge holding tank from

where it is dewatered in a filter press

Utility Effluent

The utility effluent comprising mainly of boiler and cooling tower blow down water is

collected in the Utility Collection Tank. Acid/alkali are dosed to neutralize the effluent and

pumped to the clarifier. The neutralised effluent is dosed with dolomite, coagulants and Hypo

dosing to disinfect the treated effluent and it is pumped through the Pressure sand filter and

carbon filter to remove the excess chlorine and suspended solids in the effluent. The treated

24

effluent is collected in the UF Feed tank and is pumped to Ultra Filtration system vide basket

strainer. Ultra filtration removes the following RO fouling materials like: Particulate matter,

suspended solids, bacteria, viruses, Colloidal materials (non-reactive silica, silt etc.,) and

High molecular weight organic compounds. This minimizes RO cleaning protocols and

reduces operating pressures and enhances membrane life. The filtrate from the UF is sent to

the RO feed tank

Recycling of Treated Water

The filtered water from the MBR and UF is collected and mixed in the RO feed tank. This

water is taken to a 2 stage RO plant through a micron filter which removes fine suspended

solids. The RO plant is fully automatic and the water recovery is 85%. The permeate

collected out of RO is used for recycling through cooling tower and the reject is taken to

multiple effect evaporator where it is concentrated and converted as salt.

Multiple Effect Evaporators

The multiple effect evaporator plant envisages a Five Effect Evaporator with TVR System to

get the fluid concentrate from initial concentration of 2.7% to 27% solid content, followed by

a Double Effect Forced Circulation Evaporator for further concentrating the effluent from

27% to 50% solid content. This will then be followed by drying of the concentrate in an

Agitated Thin Film Dryer to dry solid in baggable form at about 10% moisture content. The

solids from this plant, is of about 3.2 tons per day.

Holding Tank

A holding tank (lagoon) with impervious lining with a capacity to store up to 3 days effluent

generation has been constructed to take care of emergency requirements. This tank is located

adjacent to the effluent treatment plant.

25

Utility Waste collection

Clarification

Sand Filter

Carbon Filter

Ultra Filtration

RO Feed Water

Process Waste Collection

Neutralisation

Aeration

Membrane Bio Reactor

RO Reject

Evaporation Plant

425 KLD 493 KLD

RO plant

Recycle Water – 900 KLD For cooling tower make up

Solid Waste – 3.2 TPD

Boiler Blow down

Cooling tower Blow down

Water treatment plant effluent

Effluent from De-colorizer

Effluent from Plant washings

FLOW DIAGRAM OF EXISTING EFFLUENT TREATMENT PLANT

26

3.4 CHARACTERISTICS OF RAW EFFLUENT

S.No. PARAMETER UNITS RESULT

1. pH 7.0 – 7.5

2. TOTAL DISSOLVED SOLIDS mg/l 4000

3. TOTAL SUSPENDED SOLIDS mg/l 600-800

4. BIOCHEMICAL OXYGEN DEMOND mg/l 2200

5. CHEMICAL OXYGEN DEMOND mg/l 3500

6. OIL & GREASE mg/l 10-20

3.5 CHARACTERISTICS OF TREATED EFFLUENT

S.No. PARAMETER UNITS RESULT

1. pH 7.5 – 8.0

2. TOTAL DISSOLVED SOLIDS mg/l 1600-1800

3. TOTAL SUSPENDED SOLIDS mg/l <100

4. BIOCHEMICAL OXYGEN DEMOND mg/l <100

5. CHEMICAL OXYGEN DEMOND mg/l <250

6. OIL & GREASE mg/l <10

27

SOLID WASTE DETAILS – EXISTNG & PROPOSED

Sl.No Description Type of

waste

Quantity

generated

Gas

Based

Quantity

generated

Coal

Based

Sources

and waste

characteri

stics

Mode of storage

within the plant

and method of

disposal

1 Waste oil Hazardous

waste

500 Lit

per year

1000 Lit

per year

From DG

sets, Gear

boxes

Stored in barrels

in secured place

and sent to

authorized

recyclers / re-

processors

2 Used

Batteries

Hazardous

waste

2 nos. per

year

10 nos.

per year

Power back

up systems

Stored in secured

place and

disposed to the

manufacturers /

dealers on buy

back basis.

3 Multiple

Effect

Evaporator-

Salt

Non

Hazardous

waste

Generated

from

Multiple

Effect

Evaporator

3.2 TPD 4.0 TPD Multiple

effect

evaporator.

We have

submitted sample

to APPCB lab to

assess whether

this is hazardous

or non hazardous.

If it is found to be

hazardous we will

send to TSDF

4 Calcium

Phosphate

Non

Hazardous

waste

Generated

from sugar

refining

7 TPD 7 TPD Filter press

in Sugar

Refinery

Is having nutrient

value as manure.

Sent to authorized

re-processors like

fertilizer plant /

composting

facilities

5 ETP Sludge Non

Hazardous

waste

Biological

sludge

generated

from ETP

1.2 TPD 2.0 TPD Filter press

– sludge

separation

system in

ETP

Used as manure

after composting

6 Ash Solid

Waste

- 229 Cole fired

Boiler

Cement & Brick

Manufacturing

units

28

EXISTING EMISSION CONTROL SYSTEMS

NOx Control

The gas turbine has been provided with DM water injection facility to inject DM water into

the gas turbine combustor to control the NOx emission level. A DM water plant has already

been installed to cater to this requirement. The NOx level in the exhaust gas stipulated in our

Environmental Clearance is 100 ppm, and BHEL has guaranteed that NOx levels for both

natural gas and naphtha will be well below 100 ppm.

Emission Monitoring

A Continuous Emission Monitoring System (CEMS) has been installed in the main stack to

continuously measure SOx and NOx in the exhaust gas. The outputs from the CEMS will be

indicated and recorded in our DCS.

Atmospheric emissions

Type of Fuel Fuel per

Hr

Ash

%

Nox SO2 HC CO Particulate

Natural Gas 13000

sm3/hr

- - - - - -

Naphtha 10.5 tph - - - - - -

Process emissions

Pollutant Emission Rate (g/sec)

Stack

Attached to

Nox SO2 HC CO Particulate

130 TPH

Natural Gas

Fired Boiler

10.69 0.15 - 3.2 Nil

29

PROPOSED EMISSION CONTROL

SYSTEM FOR COAL FIRED BOILER

30

PROPOSED EMISSION CONTROL SYSTEM FOR COAL

FIRED BOILER

Air Environment

The only major source of air emission from the proposed coal fired boiler and steam

turbine will be burning of coal in the Boiler apart from fugitive emissions due to storage and

transportation of coal & Ash.

Emission of Pollutants

The main fuel to be used for the operation of the proposed boiler would be mixture of

Indian coal and coal imported from Indonesia, Australia & African countries etc,. The stack

emissions would be constituted of suspended particulate matter (SPM) and gaseous

emissions, particularly Sulphur Di Oxide (SO2) and Oxides of nitrogen (NOX).

Typical composition of the coal proposed to be used is given below for reference:

Fuel Composition (% by

Weight) Indian coal Imported coal

a. C 34.43 42.85

b. H2 2.25 3.48

c. N2 0.76 0.86

d. S 0.04 0.6

e. H2O 10 35

f. ASH 40 8

g. O2 12.52 8.91

h. GCV of fuel (K cal/kg) 3200 4500

Electrostatic Precipitator

The flue gas from Boiler will be passed through an Electro static Precipitator to capture both

the suspended particulate matter (SPM) . The outlet concentration of SPM would be reduced

to less than 50 mg/Nm3

Electrostatic precipitator is a device which removes dust or other finely divided particles

from flue gases by charging the particles inductively with an electric field, then attracting

them to highly charged collector plates. This is also known as precipitator. The process

31

depends on two steps. In the first step the suspension passes through an electric discharge

(corona discharge) area where ionization of the gas occurs. The ions produced collide with

the suspended particles and confer on them an electric charge. The charged particles drift

toward an electrode of opposite sign and are deposited on the electrode where their electric

charge is neutralized. The phenomenon would be more correctly designated as electrode

position from the gas phase. Pnuematic conveying system will be employed for extraction of

flyash from the ESP

Gaseous emissions

Sulphur is present to an extent of 0.5% in Indian coal and up to 0.8% in imported coal

received from Indonesia. When mixture of both the coals is fired in the boiler, it generates

suplhur dioxide to the tune of about 310 Kgs/Hr. The stack and emission characteristics are

presented in the following Table

Emission details

Particulars Value

Stack height

Number of stacks

Volume Flow Rate (m3/s)

Temperature of flue gas (°C)

Density of Flue Gas

85 m

1

35.8

145

0.858

The rate of SO2 emission using Indian and Imported coal mixture is given below

SO2 emission = 309.88 kg/hr

Stack height calculation:

H = 14 Q0.3

Where, H = height of the Stack

Q = SO2 Concentration in Kg/hr.

Hence Q = 309.88 Kg/hr.

Hence H = 78.25 m

32

To be on the safer side it is decided to go for a Stack Height of 85 meters.

Nitrous Oxide (NOx)

Emission of Nitrous oxide in flue gas will be less than 250 PPM

Air pollution monitoring system

Presence of SO2, NOx, CO will be monitored through an online stack emission monitoring

system and the emissions will be controlled within limits effectively using the data captured

through the on line system. Suspended particulate matter (SPM) and Respirable Particulate

Matter (RPM) present in the flue gas will be monitored at the frequency of once in fortnight.

Ambient air quality will be monitored once in a fortnight at four locations of the site. SPM,

RPM, SO2, NOx and CO will be monitored in ambient air quality measurement.

During Construction Phase

During excavation and transportation over roads near the proposed boiler house area, there is

a scope for local dust emissions. Frequent water sprinkling in the vicinity of the construction

activity is proposed to be done. It is proposed to make provision for water sprinklers.

Coal storage:

There is a possibility of coal dust to fly from the coal storage yard. To avoid this, we propose

to construct covered shed and coal will be stored in such covered shed. Over and above this

arrangement, water sprinklers will be provided in such shed to suppress the coal dust.

Coal dust emission from coal crushers

There is a possibility of coal dust emission from the proposed coal crusher house. Hence

suitable dust extraction cum bag filter arrangement will be installed to suck the dust coming

out of crusher house.

Coal dust emission from coal conveyors

All coal transporting conveyors will be covered with metallic sheet to prevent flying of dust

at the time of coal transportation through conveyors. In order to prevent the coal dust

33

emission from the conveyor transfer points, dust extraction hoods with bag filter will be

installed.

Dust emission from Roads

All internal roads will be asphalted to avoid generation of dust due to movement of vehicles

carrying both coal and ash. In addition to this water spray system also will be established

along side of the road to suppress the dust generation if any.

Ash handling system:

Fly ash has the potential to create air pollution. In order to eliminate this, right from the stage

of electrostatic precipitator the primary ash generation point to the ash storage silos, ash will

be handled only in closed pipes through pneumatic conveying system. Ash from silos will be

filled in covered trucks to avoid flying of ash at the time of transportation.

Handling of solid waste generated out of boiler system:

Ash is the only solid waste generated from the proposed coal fired boiler and turbine system.

Ash generated in the boiler will be safely collected in storage silos without any spills.

Such collected ash will be filled in covered trucks and transported mainly to the cement

industry for the production of cement. Apart from cement manufacture, ash will be supplied

for the manufacture of fly ash bricks, construction of roads etc., as specified in the fly ash

notification.

Green Belt development:

Since there is likelihood of dust emission from the coal handling and storage system, we will

develop green belt along the boundaries of the proposed boiler house and storage area. Apart

from this we will also develop green belt as an ongoing activity.

34

CHAPTER-IV

PREDICTION OF IMPACTS

REDICTED GROUND LEVEL CONCENTRATIONS

AR QUALITY MODELLING FOR SO2 DISPERSION

SILK ROAD SUGARS LIMITED 16/09/11

10:25:52

35

*** SCREEN3 MODEL RUN ***

*** VERSION DATED 96043 ***

C:\Users\Ramki\Desktop\so2.scr

COMPLEX TERRAIN INPUTS:

SOURCE TYPE = POINT

EMISSION RATE (G/S) = 5.00000

STACK HT (M) = 85.0000

STACK DIAMETER (M) = 4.5000

STACK VELOCITY (M/S) = 5.1000

STACK GAS TEMP (K) = 433.0000

AMBIENT AIR TEMP (K) = 293.0000

RECEPTOR HEIGHT (M) = 0.0000

URBAN/RURAL OPTION = RURAL

THE REGULATORY (DEFAULT) MIXING HEIGHT OPTION WAS SELECTED.

THE REGULATORY (DEFAULT) ANEMOMETER HEIGHT OF 10.0 METERS WAS

ENTERED.

BUOY. FLUX = 81.860 M**4/S**3; MOM. FLUX = 89.102 M**4/S**2.

FINAL STABLE PLUME HEIGHT (M) = 163.9

DISTANCE TO FINAL RISE (M) = 151.3

16/09/11

10:25:52

*** SCREEN3 MODEL RUN ***

*** VERSION DATED 96043 ***

C:\Users\Ramki\Desktop\so2.scr

SIMPLE TERRAIN INPUTS:

SOURCE TYPE = POINT

EMISSION RATE (G/S) = 5.00000

STACK HEIGHT (M) = 85.0000

STK INSIDE DIAM (M) = 4.5000

STK EXIT VELOCITY (M/S) = 5.1000

STK GAS EXIT TEMP (K) = 433.0000

AMBIENT AIR TEMP (K) = 293.0000

RECEPTOR HEIGHT (M) = 0.0000

URBAN/RURAL OPTION = RURAL

BUILDING HEIGHT (M) = 0.0000

MIN HORIZ BLDG DIM (M) = 0.0000

MAX HORIZ BLDG DIM (M) = 0.0000

THE REGULATORY (DEFAULT) MIXING HEIGHT OPTION WAS SELECTED.

THE REGULATORY (DEFAULT) ANEMOMETER HEIGHT OF 10.0 METERS WAS

ENTERED.

BUOY. FLUX = 81.860 M**4/S**3; MOM. FLUX = 89.102 M**4/S**2.

*** FULL METEOROLOGY ***

**********************************

36

*** SCREEN AUTOMATED DISTANCES ***

**********************************

*** TERRAIN HEIGHT OF 5. M ABOVE STACK BASE USED FOR FOLLOWING

DISTANCES ***

DIST CONC U10M USTK MIX HT PLUME SIGMA SIGMA

(M) (UG/M**3) STAB (M/S) (M/S) (M) HT (M) Y (M) Z (M) DWASH

------- ---------- ---- ----- ----- ------ ------ ------ ------ -----

200. 0.5321E-05 5 1.0 2.1 10000.0 180.54 30.99 29.40 NO

300. 0.7695E-02 1 3.0 3.5 960.0 235.80 76.17 53.87 NO

400. 0.5947 1 3.0 3.5 960.0 235.80 97.73 77.59 NO

500. 3.591 1 3.0 3.5 960.0 235.80 118.60 110.63 NO

600. 6.894 1 3.0 3.5 960.0 235.80 138.92 159.18 NO

700. 7.373 1 2.5 2.9 800.0 267.36 161.44 219.94 NO

800. 9.204 1 1.5 1.7 480.0 392.26 193.23 296.73 NO

900. 11.12 1 1.0 1.2 549.4 548.39 232.55 387.00 NO

1000. 11.96 1 1.0 1.2 549.4 548.39 247.93 473.17 NO

1100. 11.75 1 1.0 1.2 549.4 548.39 263.50 571.19 NO

1200. 11.18 1 1.0 1.2 549.4 548.39 279.22 680.87 NO

1300. 10.59 1 1.0 1.2 549.4 548.39 295.03 802.08 NO

1400. 10.05 1 1.0 1.2 549.4 548.39 310.90 934.77 NO

1500. 9.564 1 1.0 1.2 549.4 548.39 326.81 1078.93 NO

1600. 9.120 1 1.0 1.2 549.4 548.39 342.73 1234.58 NO

1700. 8.715 1 1.0 1.2 549.4 548.39 358.65 1401.74 NO

1800. 8.345 1 1.0 1.2 549.4 548.39 374.55 1580.46 NO

1900. 8.006 1 1.0 1.2 549.4 548.39 390.44 1770.79 NO

2000. 7.693 1 1.0 1.2 549.4 548.39 406.29 1972.76 NO

2100. 7.405 1 1.0 1.2 549.4 548.39 422.11 2186.44 NO

2200. 7.138 1 1.0 1.2 549.4 548.39 437.89 2411.87 NO

2300. 6.890 1 1.0 1.2 549.4 548.39 453.63 2649.11 NO

2400. 6.660 1 1.0 1.2 549.4 548.39 469.33 2898.22 NO

2500. 6.445 1 1.0 1.2 549.4 548.39 484.98 3159.24 NO

2600. 6.244 1 1.0 1.2 549.4 548.39 500.59 3432.22 NO

2700. 6.056 1 1.0 1.2 549.4 548.39 516.14 3717.22 NO

2800. 5.908 2 1.0 1.2 549.4 548.39 407.61 363.73 NO

2900. 5.983 2 1.0 1.2 549.4 548.39 419.09 376.11 NO

3000. 6.031 2 1.0 1.2 549.4 548.39 430.54 388.58 NO

3500. 5.959 2 1.0 1.2 549.4 548.39 487.55 452.29 NO

4000. 5.602 2 1.0 1.2 549.4 548.39 544.03 517.79 NO

4500. 5.171 2 1.0 1.2 549.4 548.39 599.94 584.71 NO

5000. 4.761 2 1.0 1.2 549.4 548.39 655.28 652.80 NO

5500. 4.400 2 1.0 1.2 549.4 548.39 710.06 721.88 NO

6000. 4.364 3 1.0 1.2 520.3 519.26 534.91 338.92 NO

6500. 4.406 3 1.0 1.2 520.3 519.26 572.50 361.24 NO

7000. 4.382 3 1.0 1.2 520.3 519.26 609.86 383.61 NO

7500. 4.310 3 1.0 1.2 520.3 519.26 647.01 405.99 NO

8000. 4.207 3 1.0 1.2 520.3 519.26 683.95 428.38 NO

8500. 4.084 3 1.0 1.2 520.3 519.26 720.69 450.76 NO

9000. 3.950 3 1.0 1.2 520.3 519.26 757.21 473.12 NO

37

9500. 3.812 3 1.0 1.2 520.3 519.26 793.54 495.46 NO

10000. 3.675 3 1.0 1.2 520.3 519.26 829.68 517.76 NO

MAXIMUM 1-HR CONCENTRATION AT OR BEYOND 200. M:

1018. 11.97 1 1.0 1.2 549.4 548.39 250.87 490.89 NO

DWASH= MEANS NO CALC MADE (CONC = 0.0)

DWASH=NO MEANS NO BUILDING DOWNWASH USED

DWASH=HS MEANS HUBER-SNYDER DOWNWASH USED

DWASH=SS MEANS SCHULMAN-SCIRE DOWNWASH USED

DWASH=NA MEANS DOWNWASH NOT APPLICABLE, X<3*LB

********************************************

* SUMMARY OF TERRAIN HEIGHTS ENTERED FOR *

* SIMPLE ELEVATED TERRAIN PROCEDURE *

********************************************

TERRAIN DISTANCE RANGE (M)

HT (M) MINIMUM MAXIMUM

------- -------- --------

5. 200. 10000.

*** INVERSION BREAK-UP FUMIGATION CALC. ***

CONC (UG/M**3) = 7.849

DIST TO MAX (M) = 13144.71

***

PLUME HEIGHT IS BELOW TIBL HEIGHT

FOR DISTANCE TO SHORELINE OF 1000.00 M.

NO SHORELINE FUMIGATION CALCULATION MADE.

***

***************************************

*** SUMMARY OF SCREEN MODEL RESULTS ***

***************************************

CALCULATION MAX CONC DIST TO TERRAIN

PROCEDURE (UG/M**3) MAX (M) HT (M)

-------------- ----------- ------- -------

SIMPLE TERRAIN 11.97 1018. 5.

INV BREAKUP FUMI 7.849 13145. --

***************************************************

** REMEMBER TO INCLUDE BACKGROUND CONCENTRATIONS **

***************************************************

38

39

AIR QUALITY MODELLING FOR SPM

M/S.SILK ROAD SUGARS LIMITED

**********************************

*** SCREEN AUTOMATED DISTANCES ***

**********************************

*** TERRAIN HEIGHT OF 0. M ABOVE STACK BASE USED FOR

FOLLOWING DISTANCES ***

DIST CONC U10M USTK MIX HT PLUME

SIGMA SIGMA

(M) (UG/M**3) STAB (M/S) (M/S) (M) HT (M) Y

(M) Z (M) DWASH

------- ---------- ---- ----- ----- ------ ------ ----

-- ------ -----

200. 0.1139E-05 5 1.0 2.1 10000.0 183.90

30.55 28.94 NO

300. 0.4597E-02 1 3.0 3.5 960.0 232.63

75.92 53.52 NO

400. 0.3174 1 3.0 3.5 960.0 232.63

97.45 77.23 NO

500. 1.824 1 3.0 3.5 960.0 232.63

118.28 110.29 NO

600. 3.411 1 3.0 3.5 960.0 232.63

138.57 158.88 NO

700. 3.650 1 2.5 2.9 800.0 262.55

160.53 219.28 NO

800. 4.623 1 1.0 1.2 529.9 528.87

213.21 310.12 NO

900. 5.795 1 1.0 1.2 529.9 528.87

228.59 384.64 NO

1000. 6.113 1 1.0 1.2 529.9 528.87

244.22 471.24 NO

1100. 5.943 1 1.0 1.2 529.9 528.87

260.02 569.59 NO

40

1200. 5.634 1 1.0 1.2 529.9 528.87

275.93 679.53 NO

1300. 5.329 1 1.0 1.2 529.9 528.87

291.92 800.94 NO

1400. 5.051 1 1.0 1.2 529.9 528.87

307.95 933.79 NO

1500. 4.801 1 1.0 1.2 529.9 528.87

324.00 1078.09 NO

1600. 4.574 1 1.0 1.2 529.9 528.87

340.05 1233.84 NO

1700. 4.368 1 1.0 1.2 529.9 528.87

356.09 1401.09 NO

1800. 4.180 1 1.0 1.2 529.9 528.87

372.11 1579.89 NO

1900. 4.008 1 1.0 1.2 529.9 528.87

388.09 1770.27 NO

2000. 3.850 1 1.0 1.2 529.9 528.87

404.04 1972.30 NO

2100. 3.704 1 1.0 1.2 529.9 528.87

419.94 2186.02 NO

2200. 3.569 1 1.0 1.2 529.9 528.87

435.80 2411.49 NO

2300. 3.444 1 1.0 1.2 529.9 528.87

451.62 2648.77 NO

2400. 3.328 1 1.0 1.2 529.9 528.87

467.38 2897.90 NO

2500. 3.220 1 1.0 1.2 529.9 528.87

483.09 3158.95 NO

2600. 3.119 1 1.0 1.2 529.9 528.87

498.76 3431.96 NO

2700. 3.024 1 1.0 1.2 529.9 528.87

514.37 3716.98 NO

2800. 3.064 2 1.0 1.2 529.9 528.87

405.37 361.21 NO

2900. 3.091 2 1.0 1.2 529.9 528.87

416.90 373.67 NO

3000. 3.104 2 1.0 1.2 529.9 528.87

428.42 386.23 NO

3500. 3.021 2 1.0 1.2 529.9 528.87

485.68 450.26 NO

4000. 2.815 2 1.0 1.2 529.9 528.87

542.35 516.02 NO

4500. 2.586 2 1.0 1.2 529.9 528.87

598.42 583.15 NO

5000. 2.376 2 1.0 1.2 529.9 528.87

653.89 651.40 NO

5500. 2.208 3 1.0 1.2 502.3 501.27

495.50 314.13 NO

6000. 2.257 3 1.0 1.2 502.3 501.27

533.41 336.54 NO

41

6500. 2.262 3 1.0 1.2 502.3 501.27

571.09 359.01 NO

7000. 2.236 3 1.0 1.2 502.3 501.27

608.54 381.51 NO

7500. 2.188 3 1.0 1.2 502.3 501.27

645.77 404.01 NO

8000. 2.126 3 1.0 1.2 502.3 501.27

682.78 426.50 NO

8500. 2.056 3 1.0 1.2 502.3 501.27

719.57 448.98 NO

9000. 1.983 3 1.0 1.2 502.3 501.27

756.15 471.42 NO

9500. 1.909 3 1.0 1.2 502.3 501.27

792.53 493.84 NO

10000. 1.837 3 1.0 1.2 502.3 501.27

828.71 516.21 NO

MAXIMUM 1-HR CONCENTRATION AT OR BEYOND 200. M:

1000. 6.113 1 1.0 1.2 529.9 528.87

244.22 471.24 NO

DWASH= MEANS NO CALC MADE (CONC = 0.0)

DWASH=NO MEANS NO BUILDING DOWNWASH USED

DWASH=HS MEANS HUBER-SNYDER DOWNWASH USED

DWASH=SS MEANS SCHULMAN-SCIRE DOWNWASH USED

DWASH=NA MEANS DOWNWASH NOT APPLICABLE, X<3*LB

*** INVERSION BREAK-UP FUMIGATION CALC. ***

CONC (UG/M**3) = 3.861

DIST TO MAX (M) = 12903.49

***************************************

*** SUMMARY OF SCREEN MODEL RESULTS ***

***************************************

CALCULATION MAX CONC DIST TO TERRAIN

PROCEDURE (UG/M**3) MAX (M) HT (M)

-------------- ----------- ------- -------

SIMPLE TERRAIN 6.113 1000. 0.

INV BREAKUP FUMI 3.861 12903. --

***************************************************

** REMEMBER TO INCLUDE BACKGROUND CONCENTRATIONS **

***************************************************

42

S.No Distance Predicted GLC’s Max. Max. TOTAL NAAQ

43

In mts GLC’s in

study

area

Predicted

GLC with

in study

area

GLC’s STANDARDS

SPM SO2

1 Plant site 0.3174 0.59 SPM - 1364

SO2 – 14.23

SPM -6.1131

SO2 -1.97

SPM – 142.113

SO2 - 25.20

200

80

2 100 2.48 1.03

3 200 3.31 0.82

4 500 1.82 3.591

5 1000 6.113 11.96

6 1500 4.80 9.561

7 2000 3.85 7.693

Note: Unit - µg/m3 - microgram/cum

SPM – Suspended Particulate Matter

SO2 – Sulphur dioxide

GLC’s – Ground Level Concentrations

All the predicted GLC are well below the National Ambient Air Quality Standards

44

CHAPTER-V

CONTROLING PARAMETERS FOR

TREATMENT PLANT

45

5.1 CONTROLLING PARAMETERS FOR TREATMENT PLANT

Various parameters play an Important role in smooth running of the treatment plant, some

important parameters and their effects on the plant are:

pH

The pH of the effluent entering the aeration tank has to be carefully monitored. The pH

should invariably maintained neutral. If the pH falls below 6.5 the fungi compeate with

bacteria and if the pH is above 8.5 the rate of metabolism in bacteria decreases.

FOOD TO MICROBES RATIO

The concentration of organic food substrate per unit mass of active biological solids present

in the aeration tank is termed as F/M ratio. If F/M ratio is not maintained within the

prescribed limits the efficiency of treatment is reduced. Proper F/M ratio results in good

sludge settlement.

F/M ratio can be defined as KgBOD5 applied / kg MLVSS. Hence to calculate F/M ratio the

BOD value has to be know. But as BOD test results are obtained after 3 days. COD is used

for calculating BOD of using BOD to COD ratio. F/M ratio of 0.14 has to be maintained in

this plant.

MIXED LIQUOR SUSPENDED SOLIDS

The concentration of suspended solids in mixed liquor has to be checked daily. In the

aeration tank MLSS of 4000 mg/l has to be maintained. This is maintained by returning the

sludge from Membrane Bio Reactor (MBR) to the required amount. If MLSS is above

4000mg/l, sludge from aeration tank has to be wasted.

46

5.2 SLUDGE HANDLING AND DISPOSAL

RETURN SLUDGE

The sludge recycled to the aeration tank from the bottom of the clarifier is called return

sludge. This is done to maintain the MLSS.

The Functions of return sludge are

a) To read influent with active biological life.

b) To keep the sludge fresh

c) To dilute the influent coming into aeration tank

d) To prevent loss of sludge during storms

The condition of the return sludge is observed from the following action.

1) Presence of bacteria : The return sludge should contain bacteria, protozoa

etc.,

2) Sludge age : The return sludge should not be too old. As this might

result in inactive sludge.

3) Relative volume : It should be seen that there is no excess of MLSS

than prescribed.

EXCESS SLUDGE

The Excess Sludge from the Membrane Bio Reactor (MBR) is send to the filter tress feed

tank. The filtrate from filter tress is fed to aeration tank. The cake discharge from filter tress

is collected and used as manure.

47

CHAPTER-VI

ANALYSIS AND SIGNIFICANCE OF TESTS

48

6.0 ANLYSIS AND SIGNIFICANCE OF TESTS

Introduction

Analysis of water and wastewater is necessary right at the planning stage of any water

purification and wastewater treatment projects. Analysis can tell the correct characteristics of

water and waste water, which depends on the proper and economical solution to the problem

of treatment. It is aid in adjustments in operation and control it is an important tool in

conducting research on the unit process and to find out simple, economical and efficient

methods of treatment.

Purpose of Analysis

The essential purpose of wastewater analysis is to the concentration and condition of the

effluent from the treatment plants and the potential effects of its discharge into receiving

body of water or onto land. It is from the out come of the analysis we say that the effluent has

met prescribed standards.

Physical analysis

The determination made in physical analysis is may include temperature, colour, odor and

turbidity.

Chemical analysis

Chemical analysis include determination of pH, TDS, SS, DO, COD, BOD, fixed and

volatile solids etc.,

49

Significance of some common tests

Temperature

It has different types of significance in sedimentation, it reflects the viscosity of fluid, in

sewage treatment, if determines the rates of extortion of BOD because temperature is a vital

factor which determines the biological growth and activity.

Turbidity :Turbidity measures are generally restricted to water/occasionally used on

sewage effluents. Turbidity in water is caused by suspension of silt clay finely divided

organic matter, microscopic organisms.

Colour : Colour of natural water is due to dissolved or colloidal substances coming from

industrial wastes contain dyes and other coloring substances. The colour of sewage reflects

its strength and condition. Fresh Sewage is Grey and stale sewage is black in colour.

Odor : It is caused by volatile substances associated with organic matter, living

organisms give specific odors like distillery waters, tannery wastes.

Taste : Taste is due to presence of chloride or sulfate ions associated with sodium,

calcium and Magnesium ions.

pH : pH is measured by pH meter using glass electrode which generate a potential varying

linearly with the pH of the solution in which it is immersed.

Solids : Solids refer to matter suspended of dissolved in water or wastewater. Solids

affect water or effluent quality adversely in a number of ways. Analysis is important in

the control of biological and physical water treatment processes.

Total Solids : A well-mixed sample is evaporated in a weighed dish and dried to

constant weight in an oven at 103 to 105 degrees centigrade. The increase in weight over

that of the empty dish represents the total solids.

Calculation

Total Solids mg/l = (A-B) X 1000/volume of ml

50

A = Weight of dried residue + dish in mg

B = Weight of dish in mg

Total dissolved solids

A well-mixed sample is filtered though a glass fiber filter and the filtrate if evaporated to

dryness in a weighed dish and dried to constant weight represents the total dissolved solids.

Calculation

Total dissolved solids mg/l = (A-B)/ sample weight mg

A = Weight of dried residue + dish in mg.

B = Weight of dish in mg

Total suspended solids

A well-mixed sample is filtered through a weighed standard glass fiber filter and the residue

retained on the filter is dried to constant weightier at 1030 to 1050 C. The increase in weight

of filter represents the total suspended solids. The difference between the total solids and

total dissolved solids provide an estimate of the total suspended solids.

Calculation

A = Weight of filter paper = dried residue in mg.

Total suspended solids = (A-B) X 1000/sample volume m1

B = Weight of filter paper in mg.

Dissolved oxygen

It represents the amount of oxygen present in the dissolved conditions no dissolved oxygen,

unless the sewage is very fresh or very weak. Presence of dissolved oxygen in sewage or

effluent from a treatment plant means that as long as D.O. remaining putrefaction odors will

not be given off. The D.O. constant decreases with the depth of the liquid.

Biochemical oxygen demand (BOD)

51

B.O.D. is usually defined as the amount of oxygen required by bacteria while stabilizing

decomposable organic matter under aerobic condition. It is the principal test applied to

sewage and industrial wasters to determine strength in terms of oxygen requirements for

stabilization B.O.D. is therefore a useful criteria for stream pollution control. The test is used

to evaluate the efficiency of various with.

Calculation

BOD mg/l = (A-B) X (Seed correction) X Initial day D.O. in sample

Sample volume ml

A = Initial day D.O. in sample

B = 3rd day D.O. in sample

Seed correction: Initial day D.O. in blank - 3rd D.O. in blank.

Chemical oxygen demand (COD)

The chemical oxygen demand is used as measure of the oxygen equivalent of the organic

matter content of a sample that is susceptible to oxidation by a strong chemical oxidant.

Most types of organic matter are destroyed by boiling with a mixture of dichromate and

sulphuric acid.

Calculation

COD mg/l = (A-B) x N x 8000/sample volume ml

Where

A = ml of Fe(NH4)2 (SO4)2 used for blank

B = ml of Fe (NH4) (SO4)2 used for sample

N = Normality of FAS

Sulphate

Sulphate is precipitated in a acidic medium of barium sulphate by addition of barium

chloride, the precipitation is carried out near the boiling temperature and after period

digestion the precipitate is filtered, washed free of chloride ignited or dried and weighed as

barium sulphate.

Calculation

Sulphate mg/l = (mg f BaSo4) x 411.6/ Sample volume

A = final weight filter paper

B = Initial weight of filter paper

52

CHAPTER-VII

OPERATIONAL PROBLEMS AND MAINTENANCE

53

7.0 OPERATIONAL PROBLEMS AND MAINTENANCE

6.1 FOAMING

Wastewater contains normally surfactants that produce foam when the wastewater aerated, if

the concentration of mixed liquor suspended solids is high the foaming tendency is

maximized. The foaming action produces a foam that contain sludge solids, grease and large

number of wastewater bacteria.

It is essential to have some method for controlling floc formation. A commonly used system

consists of a spray nozzles mounted along the top of edge of the aeration tank. Effluent or

clean water is sprayed.

Another approach is to add a small quantity of anti foaming chemical additive into the inlet

of the aeration tank.

6.2 BULKING OF SLUDGE

The bulked is one that has poor settling characteristics and poor compatibility. The two

principal types of sludge bulking problems have been identified

Caused by the growth of filamentous organisms or organisms that can grow in a

filamentous from under adverse conditions.

Caused by bound water in bacterial cells composing the floc swell through the

addition of water to the extent the density is reduced and they will not settle. The

causes of sludge bulking and are most commonly sited.

Physical and chemical characteristics.

Include flocculation in flow and strength, pH, Temperature, Staleness, and Nutrient

content.

Design limitations

54

Air supply, classifier design, return sludge pumping capacity limitations and short-

circuiting or poor mixing.

Operational causes

Low dissolved oxygen in the aeration tank, organic waste over loading of aeration

tanks and final clarifier operation.

Limited dissolved oxygen has been noted more frequently than any other cause of

bulking. If the problem is due to limited dissolved oxygen it can usually be

confirmed by operation the air blowers at full capacity. This can maintain at least 2

mg/l of dissolved oxygen; in the aeration tank.

To avoid internal plant overloading it should be determined that the liquid removed

from the sludge during mechanical sludge dewatering, or other similar operations is

not being returned to plant flow during times of peak hydraulic and organic loadings.

In an emergency situation chloride and H2O2 may be used to provide temporary

help. Chlorination of water or of return sludge has been practiced as a means of

controlling bulking.

6.3 RISING SLUDGE

Occasionally sludge that has good setting characteristics will be observed to rise or float to

the surface after a relatively short settling period. This is due to forming of Nitrogen gas at

sludge layer.

This problem can be return come by

Increasing the rate of return sludge

Decreasing the rate of flow of aeration liquor into the offending tank.

Increasing the speed of sludge collecting mechanism

Decreasing the mean cell residence time by thickening the sludge.

55

CHAPTER-VIII

SPECIAL INSTRUCTIONS TO THE OPERATOR

56

8.0 BEFORE PUMPING EFFLUENT TO PRIMARY CLARIFIER

1. pH

2. Neutral

3. Suspended Solids

4. COD – DAILY

5. BOD5 twice a week. For Assessing Treatment

AERATION TANK

1. Mix liquor Suspended Solids. (MLSS) should be maintained 3500mg/l

MEMBRANE BIO REACTOR (MBR)

1. pH

2. Suspended Solids

3. COD – DAILY

4. BOD5 Twice a week. For Assessing Treatment.

57

GREEN BELT

Green belt has been developing all around the plant. Nearly 9 types of plant species are

selected for Green belt development. The selection being based on the broad leafed nature of

the trees and its ability to attract birds.

The philosophy behind the green belt development is to improve the ecology and

environment of the surrounding of the plant by extensive afforestation.

PLANT DETAILS

1. Eucalyptus 6. Kanugu

2. Neredu 7. Neem

3. Jama 8. Mango

4. Tellamaddi 9. Palm

5. Teak

Greenbelt is a set of rows of trees planted in such a fashion, to create effective barrier

between the plant and surroundings. The greenbelt helps to capture the fugitive emissions,

attenuate the noise levels in the plant and simultaneously improving aesthetics of the plant

site. The greenbelt around the factory compound wall and in the reserve site will be

developed in keeping view of the following objectives.

1. Planting of trees in each row will be in staggered pattern.

2. The short trees will be planted in the first two rows and the tall trees in the outer

rows around the purview of the project site.

3. Since the trunks of the trees are generally devoid of foliage, it will be useful to have

shrubs in front of the tress so as to give coverage to this portion.

4. Sufficient spacing will be maintained between the trees to facilitate effective height

of the greenbelt.

58

5. Plants of native origin, fast growing type with canopy and large leaf index shall be

preferred. Do we need to mention the commitment as given in the CFO

GREEN BELT DEVELOPMENT – LAND AVAILABILITY

Total plant area of Silkroad = 43.7 acres

Area earmarked for green belt development = 75 acres

By Silkroad & Parry Infra (PICPL)

Green belt developed till Aug’11by Silkroad = 6 acres

Green belt developed till Aug’11 by PICPL = 3 acres

Area proposed to be developed by Silkroad = 17.77 acres

Area proposed to be developed by PICPL = 48.23 acres

Coal fired boiler is proposed to be located in the area originally earmarked for the

development of greenbelt in the Eastern side of the plot as marked in the site layout. M/s.

Silk road Sugar Pvt. Ltd will take equivalent area for the lease from M/s. Parry Infra

Structure Company Pvt. Ltd and develop green belt in that area.

EXISITNG GREEN BELT PHOTOGRAPHS

59

ANALYSIS REPORTS

Date: 05-05-2011

NAME AND ADDRESS : M/s. SILKROAD SUGAR PRIVATE LTD,

SEZ VAKALAPUDU,KAKINADA-533003

ANDHRA PRADESH

SAMPLE PARTICULARS : AMBIENT AIR QUALITY

SOURCE OF COLLECTION : NEAR SECURITY GATE

DATE & TIME OF START : 29-04-2011 @ 10.15 hr

DURATION OF SAMPLING : 24 hours

ATMOSPHERE CONDITION : Clear Sky

TEST REPORT

PARAMETER UNIT

RESULT

PARTICULATE MATTER –PM2.5

(size less than 2.5 microns)

g/m3 48

PARTICULATE MATTER10– PM10

(size less than 10 microns)

g/m3

89

SULPHUR DIOXIDE – SO2

(8 hours sampling)

g/m3

18

17

14.5

OXIDES OF NITROGEN - NOX

(8 hours sampling)

g/m3

19

17.4

14

60

Date: 05-05-2011



ANDHRA PRADESH


SOURCE OF COLLECTION : NEAR NORTH GATE SECURITY




TEST REPORT

PARAMETER UNIT

RESULT



g/m3 28.4



g/m3

71


(8 hours sampling)

g/m3

19.65

18.25

16.2


(8 hours sampling)

g/m3

17.32

17.36

14.3

61

Date: 05-05-2011



ANDHRA PRADESH


SOURCE OF COLLECTION : NEAR LABORATORY




TEST REPORT

PARAMETER UNIT

RESULT



g/m3 32.5



g/m3

60.4


(8 hours sampling)

g/m3

16

14

12.5


(8 hours sampling)

g/m3

18

15

13.5

CARBON MONOXIDE – CO

(24 hours sampling)

mg/m3

0.41

TOTAL HYDROCARBONS –HC

(8 hours sampling)

mg/m3

0.20

62

Date: 05-05-2011



ANDHRA PRADESH


SOURCE OF COLLECTION : NEAR PUMP HOUSE




TEST REPORT

PARAMETER UNIT

RESULT



g/m3 43.6



g/m3

71.03


(8 hours sampling)

g/m3

16

17

14.2


(8 hours sampling)

g/m3

19.5

18

15.5

CARBON MONOXIDE – CO

(24 hours sampling)

mg/m3

0.48

TOTAL HYDROCARBONS –HC

(8 hours sampling)

mg/m3

0.17

63

Date: 05-05-2011



ANDHRA PRADESH

SAMPLE PARTICULARS : STACK EMISSIONS

SOURCE OF COLLECTION : GAS TURBINE GENERATOR- 2

DATE & TIME OF COLLECTION : 29-04-2011 @ 14.25 hr

TEST REPORT

S.No. DESCRIPTION

UNIT RESULT

1. Stack height mt 35

2. Number of Pot Holes nos 04

3. C/s. Area of Stack sq.m 9.61

4. Pitot Coefficient - 0.87

5. Specific gravity of Fluid - 0.83

6. Temperature @ DGM 0C 32

7. Stack Temperature 0C 143

8. Nozzle Diameter mm 10

9. Exit Velocity m/sec 6.02

10. Gas Quantity m3/hr 208267

11. Duration of Sampling minutes 60

EMISSION RATE

1. Suspended Particulate Matter - SPM mg/Nm3 8

2 Sulphur Dioxide - SO2 mg/Nm3 1.14

3. Oxides of Nitrogen - NOX ppm 81

64

Date: 05-05-2011



ANDHRA PRADESH

SAMPLE PARTICULARS : SEWAGE WATER

SOURCE OF COLLECTION : 1) STP INLET

2) STP OUTLET

DATE OF COLLECTION : 29-04-2011

TEST REPORT

Sl.No. PARAMETER

UNIT RESULT

(1) (2)

1. pH -- 6.9 7.6

2. TOTAL DISSOLVED SOLIDS mg/l 1035 886

3. SUSPENDED SOLIDS mg/l 165 10

4. CHEMICAL OXYGEN DEMAND – COD mg/l 279 54

5. BIO-CHEMICAL OXYGEN DEMAND – BOD

(3 days incubation at 270C)

mg/l 136 23

6. CHLORIDES as Cl- mg/l 198.6 159.7

7. SULPHATES as SO4-- mg/l 59.9 55.8

8. OIL & GREASE mg/l 09 BDL

Note: - BDL denotes Below Detectable Level.

65

Date: 05-05-2011



ANDHRA PRADESH

SAMPLE PARTICULARS : NOISE LEVELS


Sl.No. SOURCE OF COLLECTION Noise levels measured in dB(A)

Day Night

1. Near Security Office 72.2 59

2. Near Pump house 76.5 62.8

3. Near Packing plant 72 66

66

Date: 05-05-2011



ANDHRA PRADESH

SAMPLE PARTICULARS : WATER SAMPLE

SOURCE OF COLLECTION : GROUND WATER


TEST REPORT

Sl.No. PARAMETER UNITS RESULT

1. pH -- 7.97

2. Turbidity NTU BDL

3. Color Hazen units colorless

4. Total Dissolved Solids mg/l 994

5. Suspended Solids mg/l 02

6. Alkalinity to Methyl orange mg/l 272

7. Alkalinity to Phenolphthalein mg/l NIL

8. Total Hardness as CaCO3 mg/l 293

9. Calcium Hardness mg/l 185

10. Magnesium hardness mg/l 109

11. Chlorides as Cl- mg/l 276.5

12. Sulphates as SO-24 mg/l 15.2

13. Fluorides as F- mg/l 0.86

14. Nitrates as NO-3 mg/l 3.92

15. Iron as Fe mg/l 0.62

16. Silica mg/l 1.73

Note: BDL denotes Below Detectable Level

67

Date: 31-5-2011



ANDHRA PRADESH


SOURCE OF COLLECTION : NEAR SECURITY GATE

DATE & TIME OF START : 20-5-2011@ 09.15 hr



TEST REPORT

PARAMETER UNIT

RESULT

PARTICULATE MATTER –PM10


g/m3 25.2

PARTICULATE MATTER10– PM2.5


g/m3

64.13


(8 hours sampling)

g/m3

17.32

16.7

14.23


(8 hours sampling)

g/m3

15.3

14.42

12.18

68

Date: 31-5-2011



ANDHRA PRADESH


SOURCE OF COLLECTION : NEAR NORTH SECURITY GATE




TEST REPORT

PARAMETER UNIT

RESULT



g/m3 27.9



g/m3

60.32


(8 hours sampling)

g/m3

17.32

14.34

13.62


(8 hours sampling)

g/m3

16.87

15.32

12.52

69

Date: 31-5-2011



ANDHRA PRADESH


SOURCE OF COLLECTION : NEAR LABORATORY




TEST REPORT

PARAMETER UNIT

RESULT



g/m3

30.16



g/m3

62.27


(8 hours sampling)

g/m3

17.2

15.8

13.12


(8 hours sampling)

g/m3

16.32

15.20

12.15

70

Date: 31-5-2011



ANDHRA PRADESH


SOURCE OF COLLECTION : NEAR PUMP HOUSE




TEST REPORT

PARAMETER UNIT

RESULT



g/m3

32.6



g/m3

65.18


(8 hours sampling)

g/m3

17.50

15.14

13.2


(8 hours sampling)

g/m3

15.68

14.19

13.6

71

Date: 31-5-2011



ANDHRA PRADESH

SAMPLE PARTICULARS : SEWAGE WATER

SOURCE OF COLLECTION : 1) STP INLET

2) STP OUTLET


TEST REPORT

Sl.No. PARAMETER

UNIT RESULT

(1) (2)

1. pH -- 6.8 7.4

2. TOTAL DISSOLVED SOLIDS mg/l 1045 887

3. SUSPENDED SOLIDS mg/l 168 9

4. CHEMICAL OXYGEN DEMAND – COD mg/l 273 56

5. BIO-CHEMICAL OXYGEN DEMAND – BOD

(3 days incubation at 270C)

mg/l 133 22

6. CHLORIDES as Cl- mg/l 197.6 159.2

7. SULPHATES as SO4-- mg/l 58.9 55.2

8. OIL & GREASE mg/l 08 BDL

Note: - BDL denotes Below Detectable Level.

72

Date: 31-5-2011



ANDHRA PRADESH

SAMPLE PARTICULARS : NOISE LEVELS


Sl.No. SOURCE OF COLLECTION Noise levels measured in dB(A)

Day Night

1. Near Security Office 71.2 58

2. Near Pump house 75.5 63.2

3. Near Packing plant 71 65

73

Date: 31-5-2011



ANDHRA PRADESH

SAMPLE PARTICULARS : WATER SAMPLE

SOURCE OF COLLECTION : GROUND WATER


TEST REPORT

Sl.No. PARAMETER UNITS RESULT

1. pH -- 7.86

2. Turbidity NTU BDL

3. Color Hazen units colorless

4. Total Dissolved Solids mg/l 985

5. Suspended Solids mg/l 03

6. Alkalinity to Methyl orange mg/l 265

7. Alkalinity to Phenolphthalein mg/l NIL

8. Total Hardness as CaCO3 mg/l 284

9. Calcium Hardness mg/l 188

10. Magnesium hardness mg/l 107

11. Chlorides as Cl- mg/l 275.2

12. Sulphates as SO-24 mg/l 14.8

13. Fluorides as F- mg/l 0.82

14. Nitrates as NO-3 mg/l 3.12

15. Iron as Fe mg/l 0.66

16. Silica mg/l 1.78

Note: BDL denotes Below Detectable Level

74

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