1

CHAPTER 1

1.1 INTRODUCTION

Wastewater treatment refers to the process of removing pollutants from water

previously employed for industrial, agricultural, or municipal uses. The techniques used to

remove the present in wastewater can be broken into biological, chemical, physical and

energetic.

Sewage is a major carrier of disease (from human wastes) and toxins (from industrial

wastes). The safe treatment of sewage is thus crucial to the health of any community. This

article focuses on the complex physical and biological treatments used to render sewage

both biologically and chemically harmless.

The waste treated is a mixture of domestic and industrial waste, with the domestic

accounting for slightly more than half of the total. Some storm water also enters the system

through leaks and illegal connections.

1.2 WASTE WATER CHARACTERISTICS

An understanding of the nature of wastewater is essential in the design and operation of

collection, treatment and disposal facilities and in the engineering management of

environmental quality. To promote this understanding, some of the wastewater

characteristics are discuss below.

Temperature

PH

Colour

Odour (ton)

Solids

Nitrogen

Phosphorus

Chloride

Toxic metals and compounds

Effluent discharge standards

Biochemical oxygen demand (BOD)

Chemical oxygen demand (COD)

Objectives treatment

Unit operation and process and flow sheet

Treatment systems

Preliminary treatment system

Primary treatment system

Secondary treatment system

Tertiary and Advanced treatment system

2

1.3 NEED OF THE PROJECT

In recent years, with increasing awareness of sewage system effect on the

environment, technology has advanced with the introduction of reticulated pipework

systems collecting swage from both domestic and industrial sources, transfer of collected

sewerage to a central treatment facility, and state of the art treatment technology to ensure

that discharge to streams and disposal of byproduct wastes do not threaten the environment.

Everyone generates west water. Typical residential water usage is from 75 to 100 gallons

per days. Seventy-three percent of the population is connected to a centralized (municipal)

waste water collection and treatment system, while the remaining 27 percent uses on-site

septic systems.

Water is not used up. When people are through with water it becomes wastewater-

better known as sewage-that must be cleaned up before it is returned to the environment for

reuse. In one way or another, all water is recycled. In the past, people had the idea that

wastewater was something that could be disposed of – it would just disappear. This idea has

caused many people to assume that when they dispose of the waste water they also dispose

of any problems or hazards related to it.

Today we recognize that we must recycle water to maintain sustainable supplies of

safe drinking water for future generations. In order to clean up or treat wastewater for

recycling, it is important to understand what waste water contains, what problems it may

cause, and what to take to clean it up.

This project also suit objectives of “Ganga Action Plan” which is executed by

Central Government of India for decreasing pollution level in holly river Ganga.

1.4 OBJECTIVES

This plant, based on up flow anaerobic sludge blanket process, was constructed and

commissioned in January 2010. This plant is designed introduction Sewage is generated by

residential, institutional, commercial and industrial establishments. It includes household

waste liquid from toilet, baths, showers, kitchens, sins and so forth that is disposed of via

sewers. In many areas, sewage also includes liquid waste from industry and commerce. The

separation and draining of household waste into grey water and black water is becoming

more common in the developed world, with grey water being permitted to be used for

watering plants or recycled for flushing toilets.

Sewage may include storm water run-off. Sewage systems capable of handling

storm water are known as combined sewer systems. This design was common when urban

Sewerage systems were first developed, in the late 19th

and early 20th

centuries. Combined

sewers require much larger and more expensive treatment facilities than sanitary sewers.

Heavy volumes of storm runoff may overwhelm the sewage treatment system, causing a

spill or overflow.

Sanitary sewers are typically much smaller than combined sewers, and they are not

designed to transport storm water. Backups of raw sewage can occur if excessive

infiltration/inflow (dilution by storm water and/or ground water is allowed into a sanitary

sewer system. Communities that have urbanized in the mid-20th

century or later generally

3

have built separate systems for sewage (sanitary sewers) and storm water, because

precipitation causes widely varying flows, reducing sewage treatment plant efficiency.

As rainfall travels over roofs and the ground, it may pick up various contaminants

including soil particles and other sediment, heavy metals, organic compounds, animal

waste, and oil and grease. Some jurisdictions require storm water to receive some level of

treatment before being discharged directly into waterways. Examples of treatment processes

used for storm water include retention basin, wetlands, and buried vaults with various kinds

of media filters, and vortex separators (to remove coarse solids). For treatment of 130 MLD

of domestic waste water.

Since its commission illegal discharge from tanneries and industrial waste water

from various industries situated in city areas is being discharged regularly to 90 outfall

sewers reaching the main pumping station from where sewerage is pumped to this plant.

The tannery waste water and industrial waste water contains leather flushing, chromium

sulphides and other toxic elements for which the STP has not been designed. Consequently

the components of the equipment are corroded.

The plant is now running at 1-/3rd

of its capacity. The treated effluent from two STPs

(36 MLD and 13 MLD) is pumped into a channel that transports water to the sewerage farm

with a total area of about 2200 hectare. From the channel, irrigation water is fed to the farm

lands. With even 100 percent efficiency in system, there is surplus sewage, which gets

discharged in Pandu or Ganges River without treatment. Comprehensive 210 MLD

sewerage treatment for old city area of Kanpur has been approved by CSMC with Project

cost of Rs. 127 cr.

The project will provide Sewerage facility in Kanpur city in Comprehensive manner

and to the present population of 42 lakhs of Kanpur city, the largest commercial center in

U.P, which is located on the river Ganges and currently discharges 426 MLD sewage

against which the installed capacity for sewage treatment in the city currently is 162 MLD.

Out of 23 Nallas in Kanpur, 19 Nallas have been intercepted.

There is hence a need to provide a sewage treatment facility otherwise this network

would keep polluting the river Ganga. The project under JNNURM will utilize this existing

gravity sewerage network under construction and the intermediate pumping stations at

Rakhimandi, Munshipurwa and Gandanala will pump the combined swaged to the main

pumping station at Bingwan rough drunk sewer along COD nala which will be treated in the

two modular units of 105 MLD each. This will benefit District II which discharges 210

MLD but does not have any treatment capacity at present.

4

CHAPTER 2

2.1 HISTORICAL DEVELOPMENTS OF UASB TECHNOLOGY

Worldwide presently over 200 full-scale UASB plants are in operation for the

treatment of both domestic and industrial waste waters. However, in India the UASB

Process is being widely adopted for domestic waste water and it can be claimed that 80% of

total UASB reactors worldwide for domestic waste water treatment is in India. The basic

approach towards selection of technology for sewage was low capital costs, low energy

requirement, low O&M costs and sustainability aspect. This was derived from the

experience of Ganga Action Plan (Kanpur-Mirzapur). Based on the successful results of 5

mld demonstration plant was constructed at Kanpur, Uttar Pradesh.

The experience GAP was mixed in terms of efficiency of treatment versus energy

consumption and cost of operation and maintenance. Drawing lessons from GAP, the YAP

opted for energy neutral and energy recover technologies like anaerobic processes for the

sewage treatment. Conventionally, anaerobic processes are to be used for the treatment of

high strength organic waste waters. However, typical hydro-dynamics of UASB coupled

with its unique characteristics of holding high granular biomass (Sunny et al, 2005), made it

possible to apply the anaerobic processes for the treatment of low strength waste waters.

After studying the performance of the demonstration plant for a few years, a full

scale UASB plant of 14 MLD was constructed at Mirzapur for treating he domestic waste

water (Draijer et al, 1992) In view of the fact that the USAB effluent does not meet

discharge standards, the plants were used in consumption with a settling pond called „final

polishing unit‟ to achieve desired BOD and suspended solids reduction. These being pilots

and experimental plants, their performance were varied.

However they were found to be promising in terms of energy consumption, biogas

yield and reduced requirements, for sludge disposal. The key factors that influenced

selection process against the conventional aerobic systems were their high energy

requirements, unreliable power supply situation in the state, and higher O&M costs; while

those in favors of UASB were their robustness, low or no dependence on electricity, low

cost of O&M Moreover, the possibility of resource recovery form biogas and aquaculture

respectively also influenced the selection process. Among the large capacity plants under

YAP, in all 28 STPs comprising 16 UASBs, 10 Waste Stabilization Ponds (WSPs) and 2

BIOFOR technology STPs with aggregate capacity of 722 MLD were constructed. UASBs

accounted for an overwhelmingly high 83% of the total created capacity.

The state of Haryana almost entirely opted for UASB technology where 10 out of

the 11 large plants were based on this. On the other hand in the state of UP there was a

balance in terms of numbers of STPs based on UASB and WSP technologies. Generally for

larger flows UASBs were considered while for smaller flows WSPs were adopted.

5

2.2 MATERIAL OF CONSTRUCTION OF UASB REACTORS

From the time of introduction of UASB concept in India in late 1980s and till date,

there have been significant modifications in the material of construction of UASB reactors,

which has significantly resulted in lowering capital costs.

The modifications incorporated in the 14 MLD UASB plant at Kanpur under GAP

were in the selection & introduction of Fibre Reinforced Plastic (FRP) (bisphenol resin) to

rectify corrosion problems and resulting in longer durability. Simpler waste water feed inlet

system in the UASB reactors is adopted to take care of choking, operation and maintenance

problems surfaced at 5 MLD plant. But, in the ten UASB STPs designed for YAP in

Haryana and recently in other UASBs, further necessary improvements were incorporated,

such as, improvements in fixing of FRP Fed inlet boxes, Gas Liquid Solids Separator

(GLSS), change in design of deflector beam, selection of most appropriate material with

respect to durability and costs etc.

In the present scenario, the main structure of UASB reactor being constructed at

various places in India is with RCC (Reinforced Cement Concrete) since concrete is easily

available and has been used in most of the developing counties for construction works. The

inside surface was coated with epoxy paint as a protective layer to avoid corrosion due to

formation of H2S and CO2. FRP of Isothelic resin class gas hoods and domes have been

providing in the GLSS (Gas-Liquid-Sold Separation). The purpose of use of FRP because of

easy construction, light weight, anti-corrosion and simple maintenance.

The feeding boxes, effluent gutters, baffle plates and gas collection pipes are also

constructed with FRP material. For feeding pipes, HDPE (High Density Polyethylene) pipes

are being used to distribute the waste water uniformly over the surface of the reactor. For

sludge discharge, CI (Cast Iron) pipe is being generally used. However, further R& D shows

that the reactors can be constructed fully in FRP using Isothelic resin instead of RCC for

small flows provided modular approach is adopted.

6

2.3 POTENTIAL OF UASB TECHNOLOGY IN OTHER DEVELOPING

COUNTRIES

In most of the developing countries, sewage treatment technologies that can provide

effluent standards at minimum cost are generally preferred. The concept of centralized

sewage treatment methods is very common in these countries. The most widely used

treatment systems are stabilization ponds, activated sludge process, trickling filters,

extended aeration system etc.

The performance of waste water stabilization ponds in achieving the goals for

developing countries appears to be satisfactory in many cases. Conventional sewage

treatment processes (like the activated sludge process) require high capital investment,

excessive consumption of energy, and high maintenance costs.

As a result, efforts to implement these methods in developing countries for water

pollution control have been seriously impeded. During the last two decades, the use of

anaerobic treatment systems particularly the UASB process in outstanding position has

increased significantly for sewage treatment in countries having warm climatic conditions

like in Brazil, India, and Columbia (C.A.L. Chernicharo, 2006).

In spite of their grate advantages, anaerobic reactors hardly produce effluents that

comply with usual discharge standards established by environmental agencies. Therefore,

the effluents from anaerobic reactors (UASB) usually require a post-treatment step as a

means of adapt the treated effluent to the requirements of the environmental legislation and

protect the receiving water bodies.

In contrast to developed countries, emphasis is given more in developing countries

to remove organic pollutants, solids and pathogens to some extent only. The ideal situation

for sewage treatment in these counties would be the complete removal of pathogens (health

protection) and the highest removal of COD (environmental protection) with recovery of

energy (methane or hydrogen) and compounds of interest: nitrogen (as NH+, NO2 and

NO3), phosphorus (as phosphate) and sulfur (as S0). As such, in terms of sustainability the

use of UASB reactors as the core unit of sewage treatment facility is most suited for this

purpose.

In addition to the removal of organic matter with low energy consumption and with

a net production of methane as, the presence of phosphate, nitrogen and sulfur reduced

compounds in the effluent opens the opportunity for the development of economically

feasible processes to recover these compounds of interest. In fact, the development of post-

treatment units of anaerobic reactors is not only important to improve the effluent quality

for environmental protection, but also to achieve the recovery of resources.

7

CHAPTER: 3

3.1 SEWAGE WATER:

Sewage water is any water household waste water with the exception of waste water

from sinks, dishwashers, laundry/wash machine, bathroom sinks, tubs, and showers which

is known as gray water. Typically, Black water, which is water contaminated by sewage,

comes from your toilet. If you use a composting toilet, 100% of your water household waste

water is black (sewage water).

3.2 SEWAGE WATER REUSE OPTIONS:

• Gardening

• Fire sprinklers

• Agricultural use

• Industrial use

• Construction Use

3.3 SEWAGE WATER CONTAMINATION:

Various sources of contamination are -

• Biological

‐ Microorganisms

• Chemical

‐ Dissolved salts – sodium, nitrogen, phosphates, chloride

‐ Chemicals – oils, fats, milk, soap, detergents

• Physical

‐ Soil

‐ Food

‐ Lint

Sewage Water

Fig. 1

8

3.4 HEALTH EFFECTS OF SEWAGE

The public health and environmental implications of sewage overflows are

tremendous. Sewage pollutes our waters with pathogens, excess nutrients, heavy metals, and

other toxins. It kills aquatic life and creates algal blooms that can suffocate fisheries.

Even worse, sewage carries pathogens that can end up in our drinking water supplies

and swimming areas. These disease-causing microorganisms cause diarrhea, vomiting,

respiratory, and other infections, hepatitis, dysentery, and other diseases. Common illnesses

caused by swimming in and drinking untreated or partially treated sewage include

gastroenteritis, but sewage is also linked to long term, chronic illnesses such as cancer, heart

disease, and arthritis.

Experts estimate that there are 7.1 million mild-to-moderate cases and 560,000

moderate-to-severe cases of infectious waterborne disease in the United States each year

and the Environmental Protection Agency estimates that between 1.8 and 3.5 million people

are estimated to get sick from recreational contact with sewage from sanitary sewer

overflows annually. While most people recover from these diseases, they can be deadly for

children, the elderly, and other patients with weakened immune systems who comprise

approximately 30% of our population at any one time.

3.5 ECONOMIC LOSS:

Debris associated with sewage probably has the highest monetary cost associated with

its presence on our beaches due to the resulting loss of tourism in addition to blockage

removal. The closing of commercial shellfish beds due to sewage contamination can lead to

high income loss.

Clean beaches have many advantages for humans and commercial seafood farms as well

as for the wildlife.

They are safer for the public.

They encourage people to come and use them, which will improve local economy.

They benefit everyone now and in the future.

These reasons prove the necessity for a solution.

9

3.6 WHAT IS THE SOLUTION?

It used to be said that “the solution to pollution is dilution.” When small amounts of

sewage are discharged into a flowing body of water, a natural process of stream self-

purification occurs. However, densely populated communities generate such large

quantities of sewage that dilution alone does not prevent pollution. Instead of discharging

sewage directly into a nearby body of water, it‟s better to let it pass through a combination

of physical, biological, and chemical processes that remove some or most of the pollutants.

This takes place in sewage treatment plants.

3.7 TREATMENT PLANT:

Sewage treatment plants neutralize and deactivate the chemicals found in the sewage

water. They work by relying on the bacteria that is found in our colons, which eat away the

nitrates, phosphates and organic matter that is found in sewage. These plants can be

expensive to build and operate for many governments, but there are cheaper alternative

which rely on nature to do most of the work. This is done by rebuilding or restoring

wetlands, because the plants and bacteria found in the wetlands will do the same thing that

bacteria in standard sewage treatment plants do. This helps the environment in two ways:

restoring wetlands and treating human waste water before it pollutes the natural waterways.

10

CHAPTER 4: METHODOLOGY

4.1 PROCESS

Primary treatment

Screening

Grit removal

Flow equalization

Fat and grease removal

Secondary treatment

Activated sludge

Aerobic granular sludge

Surface-aerated basins (lagoons)

Filter beds (oxidizing beds)

Constructed wetlands

Soil bio-technology

Biological aerated filters

Rotating biological contactors

Membrane bioreactors

Secondary sedimentation

Tertiary treatment

Filtration

Lagooning

Nutrient removal

Nitrogen removal

Phosphorous removal

Disinfection

Odor control

Sludge treatment and disposal

Anaerobic digestion

Aerobic digestion

Composting

Incineration

Sludge disposal

11

4.1.1 PRIMARY TREATMENT

The primary treatment system includes all the units of the preliminary treatment

system and the Primary Sedimentation Tank (PST), also known as the primary clarifier.

When only these units are provided for treatment it is called primary treatment of

wastewater. Fig. shows a schematic diagram of a typical primary treatment system.

Bar screen Grit chamber Skimming tank Disposal

s

Parshall PST

Approach Flume or

Channel other velocity

Control device Primary

Sump and Screening Grits Oil and sludge for

Pump house grease treatment

Schematic diagram of a typical primary treatment system

In the primary treatment system, the removal of the most of the large floating

materials takes place in the screen chamber; the most of the heavy suspended solids are

separated in the grit chamber. The primary clarifier (PST) then reduces about 60-70% of

fine settable suspended solids, which includes about 30-32% of organic suspended solids. It

should be noted that colloidal and soluble (dissolved) organic content of waste water is not

removed in the system.

12

4.1.2 SECONDARY TREATMENT

After primary treatment, if wastewater is further treated for the removal of colloidal

and soluble organic matter present in wastewater, then it is called secondary treatment of

wastewater. Normally, biological processes are employed to remove the remaining colloidal

and soluble organic as shown in figure.

PST Aeration Reactor SST Effluent

For disposal

or reuse

Influent from

Preliminary Return sludge line Secondary Sludge

Treatment

Sludge to

Treatment

Primary Sludge

(a) Secondary treatment system with activated sludge process

PST Tricking filter SST

Influent Secondary sludge

From (Humus)

Preliminary

Treatment Sludge to treatment

Primary sludge

(b) Secondary treatment system with tricking filter

Schematic diagram of biological secondary treatment system

Other biological treatment units usually provided for secondary treatment to cater to

specific needs, particularly for a small volume of wastewater, include:

Waste stabilization ponds (also known as oxidation ponds)

Oxidation lagoons (Aerated lagoons)

Oxidation ditches (Extended Aeration System)

Rotating Biological Contractor (RBC)

Up-flow Anaerobic Filter (UAF)

Up-flow Anaerobic Sludge Blanket (UASB)

13

4.1.3 TERTIARY TREATMENT

This treatment is sometimes called final or advanced treatment, and consists in

removing the organic load left after the secondary treatment, and particularly to kill the

pathogenic bacteria.

This treatment, which is normally carried out by chlorination, is generally not

carried out for disposal of sewage in water, but is carried out, while using the river stream

for collecting water for re-use or for water supplies. It may, however, sometimes be

adopted, when the outfall of sewage is very near to the water intake of some nearby town.

The different techniques available for the tertiary treatment are given in table.

Different techniques for tertiary treatment

Techniques For Complete removal

1. Granular media filtration,

ultrafiltration and micro-strainers.

Residual suspended solids.

2. Biological nitrification de-

nitrification , ion exchange and air

stripping

Removal of nitrogen, chlorine and dissolved

gases.

3. Biological and chemical process.

Residual nitrogen and phosphorus.

4. Ion exchanges Reverse Osmosis,

Electro dialysis, Chemical

Precipitation, Adsorption.

Residual dissolved inorganic solids, toxic

and complex organic compounds.

14

4.1.4 SLUDGE TREATMENT AND DISPOSAL

The residue that accumulates in sewage treatment plants is called sludge (or bio-

solids). Treatment and disposal of sewage sludge are major factors in the design and

operation of all wastewater treatment plants. Two basic goals of treating sludge before final

disposal are to reduce its volume and to stabilize the organic materials. Stabilized sludge

does not have an offensive odour and can be handled without causing a nuisance or health

hazard. Smaller sludge volume reduces the costs of pumping and storage.

It involves the process of sludge treatment and disposals are:-

Anaerobic digestion

Aerobic digestion

Composting

Incineration

Sludge disposal

Sludge dewatering

Sludge drying

15

4.2 WORK PLAN:

DURATION

Graph between activity and duration

D

C

B

A

ACTIVITY

16

4.3 PROCESS DESIGN CALCULATIONS

1 PROCESS DESIGN CALCULATIONS

A BASIC DATA ON FLOW

Total flow to plant 210 mld

8750 cum/hr

2.431 cum/sec

Peak flow 420 mld

17500 cum/hr

4.861 cum/sec

Minimum design flow 84 mld

3500 cum/hr

0.972 cum/sec

B SITE INFORMATION

General ground level at site 118.5-120.0 m above msl

H.F.L of river Pandu 119.610 m

R.L of top of rising main at inlet chamber 127.640 m

R.L of bottom of treated effluent channel 119.900 m

F.G.L at STP site 121.0-119.9 m

Sub soil water level 6.000 m

C BASIC DATA ON INFLUENT

CHARACTERISTICS

Average inlet bod (5 days@20 c) 322 mg/l

Average inlet bod load 67620 kg/day

Average inlet cod 523 mg/l

Average inlet suspended solids 418 mg/l

PH of influent 7.7

Sulphate 52.3 mg/l

Sulphides 25 mg/l

D DESIRED TREATED EFFULUENT QUALITY

Desired effluent bod to be less than 30 mg/l

Desired effluent suspended solids to be less than 50 mg/l

Desired effluent Sulphides to be less than 2 mg/l

Fecal coliform count after chlorination 10000 mpn/100 ml

17

E UNTI SIZE OF SEWAGE TREATMENT PLANT

Design of inlet chamber 4.861 cum/sec

Design peak flow 1

No. Of chambers 30 sec

Retention period 146 cum

Volume required 15.44 m

Length of chamber 2.25 m

Area of chamber 34.74 sq.-m

Depth required 4.2 m

Hence size of inlet chamber provided 15.44m × 2.25m × 4.2m

swd + 0.5 m fb

2 DESIGN OF SCREEN CHAMBER

Design avg peak flow 210 mld

Design peak flow 420 mld

2A MANUAL SCREEN CHANNEL

No. Of manual screen 2

Angle of inclination 60 deg.

Size of MS bars 50 mm wide

Thickness 10 mm

Width of clear opening 10 mm

Inclined depth 1.68 m

Total width of opening required with inclination 1.68 m

Total width of opening required with inclination 168 nos.

Nos of bars required 167 nos.

Size of channel provided 3.36m × 1.25m × ld + 0.5

m

Fb

Velocity through channel at avg flow 0.3 m/sec

2B DESIGN OF MECHANICAL SCREEN CHAMBER

Nos of mechanical screen channel 3 nos.

Angle of inclination 40 deg.

Size of ss bas 40 mm wide

Thickness 2 mm thick

Width of clear opening between bars 3 mm

Clear surface area of opening at peak flow 1.620 sq.-m

Inclined depth 1.69 m

18

Total width of opening required with inclination 1.43 m

Nos of bars required 478 nos

Nos of opening required 477 nos

Width of channel required 2.64 m

Size of channel provided 2.64m × 1.25m × ld + 0.5

m

Fb

Velocity through channel at avg flow 0.25 m/sec

Ok

3 DESIGN OF GRIT CHAMBERS

3A MANUAL GRIT CHAMBER

Nos of tank 6 nos.

Nos pf working channel 5 nos.

Design peak flow for each unit 84 mld

84000 cum/day

0.972 cum/day

3.889 m2

Effective depth provided 0.90 m

Width of channel required 4.32 m

Surface loading rate 958 cum/m2/day

Surface area 87.68 m2

Length of channel required 20.29 m2

Length if channel adopted 21.00 m

Width 4.32 m

Total depth including 0.2 m for grit storage 1.10 m

Size provided 21.0 m × 4.32m×1.10m

ld + 0.5 m

Fb

3B MECHANICALLY OPERATED GRIT CHAMBER

Nos of tanks 4

Each mechanically operated grit chamber design flow 105 mld

Surface loading rate as per cpheeo manual 959 cum/day

Surface area of grit chamber required 109.489 m2

Size of square tank provided 10.5 m × m

Size of square tank required 10.5 m × m

Liquid depth provided in grit chamber 0.80 m

19

Volume of grit chamber 88 cum

Hydraulic attention period at peak flow 1.2 minute

Free board provided 0.5 m

Size of mechanically operated grit chamber provided 10.5 m × 10.5m×0.8m ld

+ 0.5 m

Fb

4 PARSHALL FLUME WITH ULTRASONIC FLOW

METER

Nos of channel with parshall flume 1

Design peak flow 420.0 mld

4.861 cum/sec

Velocity in channel considered 1 m/sec

Width of channel considered 4.000 m

Depth of flow 1.2 m

Throat width of parshall flume provide 900 mm

5 DESIGN OF UASB REACTORS

Design capacity or peak flow 420 mld

17500 mld

Design capacity or average flow 210 mld

8750 cum/hr

Nos. Of unit for 210 mld 16 nos.

Minimum design flow 84 mld

3500 cum/hr

0.972 cum/sec

Upflow velocity recommended for peak flow as per nit 1.5 m/hr

Considering the upflow velocity on peak flow 1.15 m/sec

The surface area of each UASB reactor required 951.09 m2

Spacing of gas collection beams considered 4 m

Length of UASB reactor required in multiple of 4 m 32 m

Width of each reactor required 29.7 m

Width of reactor considered 30.00 m

Surface area of each UASB reactor 960.00 m2

Width of glass considered 3.0 m

Area of aperture 240.00 m2

Velocity through aperture on peak flow 4.6 m/hr

Upflow velocity at dry weather flow 0.228 m/hr

20

6 SLUDGE PRODUCTION IN UASB REACTOR

Design inlet BOD (5 days @ 20 C) 322 mg/l

Design inlet BOD load 4224.64 kg/day

Avg inlet COD 523 mg/l

Design inlet COD load 6861.76 kg/day

COD removal efficiency 65 %

COD removal in reactor 339.95 mg/l

Design temperature 20 c

Total bacterial yield factor 0.007 kg vss/kg cod

removed

7 BIOLOGICAL SLUDGE PRODUCTION

Vss production in reactor due to cod 23.8 mg/l

Degradation of organic compound 50 %

Solids in digested sludge 11.9 mg/l

Biological sludge production 11.9 mg/l

Biological sludge production per reactor 156.1 kg/day

Tss in influent given iv nit 418.0 mg/l

Min. Tss reduction in reactor 65 %

TSS in effluent 146.3 mg/l

VSS in influent given in nit 178.0 mg/l

VSS in effluent 57.9 mg/l

VSS in digested sludge 60.10 mg/l

Ash content 57 %

Sludge production due to ash content 156. Mg/l

Sludge production due to tss per reactor 216.1 mg/l

Total sludge production per reactor per day 2991 kg/day

Sludge concentration 65 kg/cum

Sludge volume production per reactor per day 46.0 cum

Sludge retention time 38 days

Total sludge mass in reactor 113658 kg

Sludge volume 1749 cum

Area of one reactor 960.0 m2

Maximum sludge bed height % of height up to gas

collector

80%

Height of deflector beam 2.28 m

Height of glass from edge of deflector beam 0.87 m

Height of glass 1.49 m

Total sludge in UASB reactor required 5.04 m

Total sludge in UASB reactor provided 5.20 m

Volume of each reactor 4992 cum

HRT on average flow 9.13 hrs

21

COD loading per day 6862 kg

COD loading per cum per day on each reactor 1.37 cod/cum/day

8 DESIGN OF COMPONENTS OF UASB REACTOR

Angle of gas collector 50 deg

Min: hood width 0.44 m

Min. Settling zone detention time 1.20 hr

Max. Feed inlet pipe distance 2.00 m

Angle of deflector beam 45 deg

Minimum overlap 0.15 m

C/c distance of gas collector 4.00 m

Max. Weir loading 5.00 m/hr

Min. bio gas 0.08 mg/l

Min. Sulphides at reactor outlets 22.00 mg/l

22.00 mg/l

Min. Methane content in bio gas 70%

H2s content in bio gas 1%

Min. Nos. Of sludge withdrawal pits in one reactor 4

Min. Sludge withdrawal points per sw pits 2

Total no. Of reactor provided for 210 mld avg. Flow 16

Area of first 8 nos. UASB reactor provided 32 m × 28 m = 896.0 m2

Area of second set of 8 nos. UASB reactor provided 32 m × 32 m = 1024 m2

Total area of all 16 reactor 15360 m2

Hence size of each of 8 nos UASB reactor provided 32.0m × 28.0m × 5.2m ld

+0.5m fb

Size of each of other 8 nos UASB reactor provided 32.0 m x 32 m x 5.20 ld

+ 0.5 m fb

Reactor size 32 m × 28 m

Design peak flow to each reactor 24.5 mld

Length of one reactor 32.0 m

Reactor width provided 28.0 m

Distance of gas collector 4.0 m

Nos. Of gas collector beam in one reactor 8

Area covered by one feed point 4.0 m2

No. Of feeding points in one reactor 224

No. Of feed inlet box provided in one reactor 16

Nos. Of feed pipes in one feed inlet box 14

Size of pipe provided (hdpe pipe) 110

Nos of feed boxes per distribution box 8

Nos of distribution box per reactor 2

Size of pipe provided 180 mm

Width of gloss at bottom 3.00 m

Weir loading at peak flow 448.0 m

22

9 DESIGN OF FEED INLET BOX(FRP)

Size of one outflow chamber 0.2m × 0.2 m × 0.2 m

Length of feed inlet box 2.04 m

Width of central chamber 0.4 m

Width of feed inlet box 1.12 m

Depth in central chamber 0.5 m

10 DESIGN OF NOTCH WEIR PLATE OF FEED

INLET BOX (FRP)

Nos of feed pipes in one feed box 14

Peak flow in one reactor 24.5 mld

Peak flow in one feed inlet box .01772 vum/sec

Flow through 90' v notch .00127 cum/sec

Depth of flow in v notch 0.055 m

Peak flow in one reactor 24.5 mld

0.289 cum/sec

Peak flow in one effluent gutter 0.0181 cum/sec

Avg. flow of each gutter 0.0090 cum/sec

Assuming width of each gutter 0.2 m

Velocity in gutter 0.8 m/sec

Depth of flow at discharge end 0.08 m

Depth of flow at mid-point 0.100 m

Avg. Depth of flow in one effluent gutter 0.100 m

11 DESIGN OF V NOTCH N WEIR PLATE FOR

EFFLUENT GUTTER

Peak flow in one effluent gutter 0.0181 cum/sec

Provided triangular v notch with an angle 90 degree

Assuming depth of flow in notch 0.03 m

Flow through v notch 0.00022 cum/sec

Nos of v notch per gutter 82

Reactor size 32 m x 32 m

Design peak flow to each reactor 28.00 mld

Design average flow to each reactor 14.00 mld

Length of one reactor 32.0 m

Reactor width provided 32.0 m

Distance of gas collector 4.0 m

Nos if gas collector beam in one reactor 8

Area covered by one feed point 4 sq-m

No of feeding points in one reactor 256

23

Nos of feed inlet box provided in one reactor 16

Nos of feed pipes in one feed inlet box 16

Size of pipe provided (D of hdpe pipe) 110 mm

Nos of feed boxes per distribution box 8

Nos of distribution box per reactor 2

Size of pipe provided 180 mm

Width of glass at bottom 3.00 m

Total weir loading in one reactor 512.0 m

Weir loading at peak flow 2.279 cu/sec

12 DESIGN OF FEED INLET BOX (FRP)

Size of one outflow chamber 0.2 m× 0.2 m × 0.2 m

swd

Length of feed inlet box 02.24 m

Width of central chamber 0.4 m

Width of feed inlet box 1.12 m

Depth in central chamber 0.5 m

13 DESIGN OF V NOTCH WEIR PLATE OF FEED

INLET BOX (FRP)

Nos of feed pipes in one feed box 16

Peak flow in one reactor 28.0 mld

0.324 cum/sec

Peak flow in one feed inlet box 0.02025 cum/sec

Peak flow in one feed inlet pipe 0.00127 cum/sec

Flow through 90 degree v notch 0.00127 cum/sec

Depth of flow in v notch 0.055 m

14 DESIGN OF EFFLUENT GUTTER INSIDE

REACTOR

Peak flow in one rector 28 mld

Peak flow in one effluent gutter 0.0181 cum/sec

Avg. Flow in one effluent gutter 0.009 cum/sec

Assuming width of each gutter 0.2 m

Velocity of flow in gutter 0.8 m/sec

Depth of flow at discharging end 0.08 cum/sec

Depth of flow at mid-point 0.100 m

Avg. Depth of flow in one effluent gutter 0.100 m

24

15 DESIGN OF V NOTCH IN WEIR PLATE FOR

EFFLUENT GUTTER

Peak flow in one effluent gutter 0.0181 cum/sec

Provided triangular notch with an angle 90 deg

Assuming depth of flow in notch 0.03 m

Flow through v notch 0.00022 cum/sec

Nos of v notch per gutter 82

Design of division box

Nos of outlets from box 32

Nos of division box for 32 x 28 m reactor 16

Peak flow to each compartment 6.125 mld

Retention period for each chamber 10 sec

Volume of each compartment 0.729 cum

Liquid depth considered 1.000 m

Width of weir considered 1.870 m

Width of chamber provided 0.90 m

Nos of division box for 32 x 32 m 16

Peak flow to each compartment 7.000 mld

Retention period for each chamber 10 sec

Volume of each compartment 0.810 cum

Liquid depth considered 1.0 m

16 DESIGN OF DISTRIBUTION BOX

Design flow 7.000 mld

Retention time for common chamber 15 sec.

Volume of common chamber 1.215 cum

Nos of outlets from distribution box 8

Width of each outlet box 0.50 m

Length of common chamber 2.60 m

Depth of common chamber 1.20 m

Width of common chamber 0.39 m

Width of distribution box 1.798 mm

Size of distribution box 2.60 m× 2.163 m × 1.20

ld + 0.5 m fb

17 BIO GAS PRODUCTION

Influent COD 523 mg/l

COD reduction in reactor 65%

COD reduction in reactor 340 mg/l

Bio gas production per reactor 356.81 cum

Bio gas by all reactor 5708.98 cum

25

18 DESIGN OF FACULTATIVE AREATED

LAGOONS

Design flow

Nos of units 2

Retention period 12 hrs

Volume required 52500 cum

Depth of lagoons provided 4 m

Area of aerated lagoons required 13125 m2

Size of each aerated lagoons provided 13125 m2 × 4.0m ld + 0.5

m fb

Capacity of aerated 39.38 kw

Sulphides in effluent of FPU 22 mg/lit.

Oxygen requirement 19.3 kg/hr

Total capacity of aerator‟s 74.31 hp

19 DESIGN OF CHLORINE CONTACT TANK

Design flow 210 mld

Numbers of tank 1

Retention time 30 min

Volume of each tank required 4375 cum

Liquid depth provided 3 m

Area of tank provided 1458.3 m2

Width of tank taken 30.0 m

Length of tank 48.6 m

Size of chlorine tank provided 48.6 m × 30.0 m × 3.0 ld

+ 0.5 m fb

Chlorine design rate 5. Mg/l

Consumption of chlorine per day 1050 kg

20 DESIGN OF SLUDGE SUMP AND PUMP HOUSES

Sludge produced by one reactor per day 46.02 cum

Capacity of wet well provided 184.1 cum

Depth of wet well provided 5.0 m

Area of wet well required 36.8 m2

Length of wet well required 8.0 m

Width of wet well 4.6 m

Sludge pump required 3

Nos of working pump 2

Capacity of each pump provided 23 cum/hr

Power required with 50 % efficiency of pump 5.0 kw

Hence size of sludge sump 8.0 m × 4.6 m × 5.0 swd

+ 0.5 m fb

26

4.4 HYDRAULIC DESGN CALCULATIONS

1 HYDRAULLIC DESIGN CALCULATIONS

Flow to STP 210 mld

210000 cum/day

8750.0 cum/hrs

145.833 cum/min

2.431 cum/sec

Peak factor 2

Peak flow (q peak ) 420 mld

42000 cum/day

17500.00 cum/hr

291.667 cum/min

4.861 cum/sec

2 GENERAL INFORMATION OF LEVELS

General ground level at site 118.5-120.0m above

MSL

H.F.L of river Pandu 119.61 m

R.L of top rising main inlet chamber 127.64 m

R.L of bottom treated effluent channel 119.90 m

F.G.L at STP site 122.00 m

Sub soil water level 6.00 m

Twl at inlet chamber 127.215 m

Total head loss in STP 6.115 m

3 HYDRAULIC LOSSES CALCULATIONS AND

SIZING OF CONDUIT

IL of conduit at discharge point 119.90 m

Length of final effluent channel 250.0 m

Width of channel considered 4.10 m

Critical depth in channel considering free fall in

river(Dc)

Dc =(q/b*Og) )^2/3

0.523 m

Depth of flow in the final effluent channel is

provided

1.2 m

Twl of flow in the effluent channel is provided 121.100 m

Peak flow in final effluent channel 4.8611 cum/sec

Velocity in channel assumed 1.00 m/s

27

Liquid depth in channel 1.186 m

Using manning‟s equation (V) 1/n × r^2/3×s^1/2

For concerts surface (N) 0.012 m

Hydraulic radius (R) 0.757 m

Slope in channel required (S) 0.000209

Slope in channel provided (1 in 4600) 0.000217

Depth of flow at peak flow at the end 1.200 m

Critical velocity at the end at peak flow 0.988 m/s

Depth of flow provided in final effluent channel

outside (CCT) 119.954 m

Twl in final effluent near CCT 121.154m

Free fall in channel from CCT 0.125 m

Crest level of CCT outlet weir 121.275

Nos. Of CCT units 1

Flow through 1 CCT 4.8611 cum/sec

Total length of weir 3000 mm

Clear length of weir (B) 30 m

Width of weir 150 mm

Head over rectangular weir=(q/1.77b)^2/3 0.205 m

Twl of CCT 121.481

CCT received the flow from final polishing pond-ii

through treated effluent

Channel. The open channel receive the 50%flow

from land compartment of

FPU-ii and balance 50% from is compartment of

FPU-ii

Considering losses in entry point of CCT 0.049 m

Twl of channel at inlet of CCT 121.530 m

Peak flow in effluent channel 100% 4.8611 cum/sec

Width of channel considered 4.10m

Depth of flow considered as above 1.2m

Velocity in channel 0.99m/sec

Il of channel at outlet FOU-ii 120.33m

Twl of channel at channel at outlet of FPU-ii 121.530 m

Free fall in effluent channel from FPU-ii 0.1 m

Level of crest of weir at FPU-ii outlet 121.630

Nos of FPU units 2.000

Flow through one FPU 2.4306

Total length of wire 30000mm

Total width of end supports (2x500) 1000 mm

Clear length of wire b 29m

Head over rectangular wire=(q/1.77b) 2/3

0.1336m

28

Twl at outlet of FPU-ii 121.764m

Twl at inlet of FPU-ii 121.764m

Level crest of wire of FPU-ii inlet 121.764m

Total length of wire 36000m

Clear length of wire 36 m

Width of wire 150mm

Head loss over wire (H) Qa/(1.65×b)2/3

0.1213m

Head over wire 0.121m

Head loss in pipe from collection channel of aerated lagoon to overflow

chamber in FPU-ii

Nos of pipe for each aerated lagoons 1

Peak flow through each conduit 2.431 cum/sec

Size of RCC NP3 pipe provided 1.8m

Velocity through sever 0.95563m/sec

Velocity head (v2 /2g) 0.0465m

Head loss at entry and exist [1.5x (v2/2g)] 0.0698m

Length of pipe from collection chamber to FPU-i 25.0m

Conduit material Rcc

Cr value for modified h-w formula 1.00

Frictional losses in pipe using modified Hazen-

Williams formula,

HF= (l*(Q/CR)1.81

/994.62*D4.81

0.07 m

Total head loss in pipe 0.07724m

Twl in collection channel 121.842m

Considering free fall in collection channel of aerated

lagoon

0.13m

Level at crest of channel 121.000m

Head over the weir 0.035m

Twl at outlet of aerated lagoon 122.007

Considering losses in lagoon 0.3m

Twl at aerated lagoon considered 122.037

Aerated lagoon receives flow from common

collection channel of UASB

Reactors through 1800 mm RCC pipe. The flow is

further divided in three

Parts for better distribution in

Aerated lagoon

Size of each overflow chamber 4m×4m

Level of crest of overflow channel 122.050

Length of weir crest 12.000m

Flow to each chamber 0.810 cum/sec

29

Head over the weir 100m

Twl in distribution overflow chamber 122.150 m

HEAD LOSS THROUGH PIPE FROM COLLECTION CHAMBER TO

AERATED LAGOON

Nos. Pipe for each aerated lag through lagoons 1

Peak flow through each conduct Q 2.431 cum/sec

Size of rcc np3 pipe provided 1.8 m

Velocity through sewer 0.95563m/sec

Velocity head (V2/2g) 0.0465m

Head loss 0.0

Head loss in bend 0.0233 m

Length of pipe from collection chamber to FPU-i 25.0 m

Conduit material RCC

CR value for rcc pipe for modified h-w formula 1.00

WORK VALUE MEASURED in

Critical losses in pipe .using modified Hazen-

Williams formula.

HF = (l*(q/cr1.81

)/99.62*d4.81

0.007 m

Total head loss in pipe 0.10051 m

Twl in collection chamber effluent chamber 122.251 m

Consider the topography of the area and head

available the twl in collection can be increased

123.266 m

Losses in the effluent outside UASB reactor

considered (maximum)

0.300 m

Width of channel 1.200 m

Velocity of flow 1.000 m

Depth of flow during flow 0.608 m

Il of channel 0.506 m

Free fall in channel effluent channel considered 122.760 m

Il of frp in the UASB reactors 0.100 m

Nos. Of gutter in the one reactor 123.666 m

Peak flow to each reactor 16 m

Peak flow to each frp reactor 0.30382 m

Width of each frp gutter 0.00949 m

Width of each gutter 0.2 m

Critical depth in the gutter considering free fall

in the

m

Depth of the starting point (at middle of gutter ) 0.106 m

30

Average depth of flow in gutter 0.084 m

Depth of flow in the gutters considered 0.110 m

Twl in the frp gutter provided 123.776 m

V- notch provided in frp gutters@ 250 m

Nos of v-notch in 1 gutter 83 m

Flow through each v-notch 0.000057 cum/sec

Head over weir in v-notch(q/1.48)2/5 0.026 m

Free fall in gutter 0.054 m

Twl in UASB reactors 123.856 m

Nos of feed inlet pipes in one reactor 224 m

Flow through each pipe 0.00136 m

Size(outer dia)of feed inlet pipe 90 m

Velocity through pipe (id=0.098m) 0.26997 cum/sec

Velocity head 0.00371 m

Losses through pipe 0.012 m

Water level in outlet box of feed inlet box 123.868 m

For proper distribution each outlet box receive

flow through v-notch

Flow through v-notch q=8/5 cd 2g h tan 0/2 0.001356337 cum/sec

Head over v-notch h (q/1.40)2/5 m

0.061 m

Total depth of v-notch provided 65 cum/sec

Fee fall after the v-notch considered 0.1 m

Twl center chamber required 124.033 m

Difference between twl in reactor and in feed

intent

0.177 m

This head shall be helpful to clear in feeding

Each feed box will receive the flow distribution

box through 180 mm hdpe pipe

Consider id of hdpe pipe 0.019 cum/sec

Consider id of hdpe pipe 0.155 m

Velocity through pipe 1.00684 m/sec

Velocity head V2/2g .0517 m

Head loss at enter and exit 0.775 m

Head loss in 3 nos bends (max) 0.0775 m

Strength of one pipe considered (max) 23.0 m

Material Hdpe m

Value of hdpe pipe for modified h-w formula 1.0 m

Friction losses pipe using modified Hazen

Williams formula

HF=(l*(q/cr1.81

)/994.62*d4.81

0.139 m

31

Total head in pipe at peak flow 0.2939 m

Total head loss in pipe at average flow 0.0714 m

Twl in outlet box of distribution box 124.327 m

Free fall considered in outlet box at peak low 0.1 m

Level of edge wire 124.427 m

Width of wire 0.6 m

Head over rectangular wire (q/1.77b)2/3

0.0702 m

Twl at center chamber of distribution 124.497 m

Each distribution box will the flow division

through 450 mm id/di pipe

m

Flow through each 450 mm id pipe 0.154 m

Size of pipe 0.45 m

Velocity through pipe 0.95563 m

Velocity head v2/2g 0.0465 m

Lead loss at entry exit 0.0698 m

Lead loss in 4nos bends (max) 0.0931 m

Length of one pipe considered (max) 135.0 m

Pipe material Cl m

Value for ci pe for modifier h-w formula 0.85 m

Considering same twl in connecting as

manual grit chamber

126.765 m

Width of connecting channel 6.0 m

Peak flow in channel 1.620 m

Velocity in channel assumed 1.0 m

Liquid depth in channel 0.27 m

Using manning equation 1/n*r2/3*s1/2 m

For concrete surface 0.012 m

Hydraulic radius 0.248 m

Slop in channel provided (1 in 1700) 0.000924 m

Depth of flow at peck flow 1.25 m

Of connecting channel 125.515 m

Twl at d/s of fine bar screen same as u/s of

manual grit chamber

126.7635 m

Considering maximum head loss across

screen

0 m

Twl at u/s of bar screen 127.065 m

Depth of flow at screen 1.25 m

Of screen channel 125.815 m

Considering head loss across the open

channel gates

0.15 m

Twl inlet chamber of STP 127.215 m

32

CHAPTER 5

DESCRIPTION OF UNITS

5.1 MAIN PUMPING STATION ( M.P.S)

Pumping stations are facilities including pumps and equipment for pumping fluids

from one place to another. They are used for a variety of infrastructure systems, such as the

supply of water to canals, the drainage of low-lying land, and the removal of sewage to

processing sites.

A pumping station is, by definition, an integral part of a pumped-storage

hydroelectricity installation.

Sewage treatment plant at Bingawan main pumping station detail’s:---

Delivery pipe 1200 mm

Suck pipe 800 mm

Cost of M.P.S 26 crore‟s approx.

Total number of pumps 12 pumps

Working at a time 6 pumps

After the treatment of sewage water, treated water delivered to the Pandu River.

Total cost of the full plant approx. 150-170 corer‟s.

Pumping station is the most important part of any treatment plant or sewage

treatment plants. It transfers the fluids of water one place to another place for treatment

process or supply purpose of fluids of water.

OUTLET PIPE OF M.P.S

(During Construction)

Figure-2

33

5.1.1 WORKING OF MAIN PUMPING STATION

Main pumping station in sewage collection system also called lift stations, are

normally designed to handle raw sewage system that is fed from underground gravity

pipelines (pipes that are sloped so that a liquid can flow in one direction under gravity).

Sewage is fed into and stored in an underground pit commonly known as a wet well.

Sewage pumping stations are typically designed so that one pump or one set of

pumps will handle normally peak flow condition. And in this pumping station there are too

set of 6-6 pumps on the both adjacent side of MPS and three- three pumps are running from

both side at a working hours (4 hours from 8 hours).

Fig. 3- Main Pumping Station

(During Construction)

34

Fig. 4-Main Pumping Station

(After Construction)

Fig.5

Main pumping station one side pipes

35

During working hours, in this pumping station there are to set of 6-6 pumps on the

both adjacent side of MPS and three- three pumps are running from both side at a

working hours (4 hours from 8 hours). Three pumps are working only four hours

continuously from both side, after that remained all six pumps are worked.

Fig. 6

Main pumping stations both side pipes

36

5.2 INLET CHAMBER (Receiving Chamber)

The raw sewage will be delivered through 2200mm diameter RCC pipe into the inlet

chamber. The function of the inlet chamber is to reduce the incoming velocity which is

constructed in RCC M30 concrete. Fig2 Inlet Chamber. The chamber is provided with

coarse screen for screening the coarse particulars coming through the inlet pipe which

reduce the choking of pump and to ensure smooth running. All internal surfaces are finished

with smooth cement plaster with water proofing compound. All outside surface above

ground level are finished with thick sand faced plaster.

Figure-7

Inlet Tank

37

5.3 SCREENING CHANNEL

5.3.1 Mechanical Screening Channel Fine screen channels are provided to remove still finer suspended/floating particles

like leaves, paper, weeds etc. that is escaping coarse screen. They may escape from primary

clarifier and attach themselves to the weir of clarifier thereby preventing uniform over flow.

Sometimes the screening might choke sludge pipe line and also sludge pumps. The screens

installed are mechanical whereby the cleaning is done by means of a mechanical lift and

removed by using belt conveyor. This prevents any manual handling of the screen and is an

added advantage. The numbers of mechanical screens installed in the plant are three which

further allowed the flow into grit channel.

5.3.2 Manual Screening Channel Two manual screen channels are provided with dimensions of 6×3.36×1.25m + 0.5m

FB to overcome any mechanical problem or any power failure situations at R.L. of 125.815

m. At the entrance of these channels fine screens are installed to prevent the entrance of

coarser particles into channel that may affect the further process of treatment.

Screening Channel

Figure-8

38

5.4 SETTLING TANK

5.4.1 Detroiter Tank

Four Detroiter tanks two manual screen channels are provided with dimensions of 10.5

× 10.5 × 0.8m + 0.5 FB at R.L. of 125.565 m. The grit removal consists of two essential

elements-grit collecting mechanism and grit washing mechanism. Each operates separately

but in hydraulic communication with one another. The removal of grit is essential to protect

moving mechanical equipment from abrasion and accompanying abnormal wear.

Reduce formation of heavy deposits in pipeline, channels and conduits.

Fig. 9 - Detroiters Tank

39

Mechanism

The Detroiter is a continuous flow tank in which the grit settles due to gravity and

the water overflows though the outlet weir on the opposite side. The settled grit is scraped

by means of a scraper mechanism towards the openings on the classifier sidewall at the

bottom. The collection chamber works on velocity principal and is so designed that only grit

settles down and organic matter overflows. The classifier mechanism consists of a

reciprocating rake driven by a gear drive fitted with a motor. The grit collected is given a

thorough washing and is delivered from the top of the classifier through a Parshall Flume

for further disposal.

5.4 .2 Manual Grit Chamber

Grit chambers are nothing but like sedimentation tanks, designed to separate the

intended heavier inorganic materials) (specific gravity about 2.65) and to pass forward the

lighter organic materials. Hence, the flow velocity should neither be too low as to cause the

settling of lighter organic matter, nor should it too high as not to cause the settlement of the

silt and grit present in the sewage. Six chambers, each with the dimensions of 21.0 4.32 1.1

m + 0.5 m FB at R.L of 125.565 m are provided. A center of these chambers a hole of 30

cm diameter is made to remove the settled grit manually.

Generally grit channels are designed to remove all particles of higher specific

gravity of 2.65 or so with a nominal diameter of 0.20 mm and more, having settling velocity

of about 21 mm/sec at 100/C, although some grit removal channels are designed to remove

particles above 0.15 mm size, having settling velocity of about 15 mm/sec at 100/C. It is not

at all desirable to remove any organic matter in the grid chambers because no further

treatment of removed grit is provided.

Fig. 10- Manual grit chamber

40

5.5 PARSHALL FLUME

A Parshall flume is a fixed hydraulic structure (104.5m) used in measuring

volumetric flow rate in surface water and waste water treatment plant. The Parshall flume,

R.L. 123.965m, accelerates flow though a contraction of both the parallel sidewalls and a

drop in the floor at the flume throat. Under free-flow conditions the depth of water at

specified location upstream of the flume throat can be converted to a rate of flow.

The Weirs, in which the discharge is proportional to head, are known as

Proportional Weirs. By float-regulated dosing devices the flow over a proportional weir

can be determined, e.g. in the case of a rectangular notch it is proportional to 3h/2 and in the

case of a triangular V-notch) the discharge is proportional to 5h/2, etc., where h is the head

over weir. The inverse problem is for a known head-discharge relationship finding the shape

of a weir constitutes the design of proportional weirs.

Fig. 11- PARSHAL FLUME

41

5.6 DIVISION BOX

Division box is a long distributing channel which is dividing into 32 blocks to

distribute the sewage flow into different distribution boxes. It consists of a baffle wall

through which the sewage is uniformly distributed throughout the channel. Each box has a

dimension of 2.2×1×1.75 m with a R.L. of 123.665 m. 32 Densities iron pipes of diameter

450 mm are used to carry sewage from division box to distribution box to feed the reactors.

Each pipe has a flow regulating valve at the entrance of the plant.

Fig.12 - Division Box after Construction

42

5.7 DISTRIBUTION BOX

Distribution box is the structural unit which is installed just before the UASB

reactors. The main function of the distribution box is to receive the flow from the division

box and feeds to reactors. At its bottom, flow from division box is stored and stabilized and

flow is further fed to reactors using 8 outlets of FRD pipes at the side of distribution box.

Fig. 9- Distribution Box

Fig.13 - Distribution Box

43

5.8 UPFLOW ANAEROBIC SLUDGE BLANKET (USAB) REACTORS

Up flow Anaerobic Sludge Blanket (UASB) reactors are anaerobic centralized or

decentralized industrial wastewater or block water treatment system achieving high removal

of organic pollutants. The wastewater flows upwards in a vertical reactor through a blanket

of granulated sludge.

Bacteria living in the sludge break down organic matter by anaerobic digestion,

transforming it into biogas. Solids are also retained by a filtration effect of the blanket. The

upflow regime and the motion of the gas bubbles allow mixing without mechanical

assistance. Baffles at the top of the reactor allow gases to escape and prevent an outflow of

the sludge blanket. As all aerobic treatments, UASB require a post-treatment to remove

pathogens, but due to a low removal of nutrients, the effluent water as well as the stabilized

sludge can be used in agriculture. UASB reactor (Under construction) in the UASB process,

the whole waste is passed through the anaerobic reactor in an upflow

Mode, with a hydraulic retention time (HRT) of only about 8-10 hours at average

flow. No prior sedimentation is required. The anaerobic unit does not need to be filled with

stones or any other media; the up flowing sewage itself forms millions of small “granules”

or particles of sludge which or held in suspension and provide a large surface area on which

Organic matter can attach and undergo biodegradation. The gas produced is collected

through gas hood. Anaerobic systems function satisfactorily when temperatures inside the

reactor re above 18-200C .Excess sludge is remove from time to time through a separate

pipe and sent to sludge sump under the action of gravity.

There are 16 UASB Reactors (32x28x5.2m) in 4rows each having 4 reactors. Each

reactor is subdivided into 8 parts each having a deflector beam, and is fed by two

distribution boxes from both sides. Sludge generated in reactors flows into sludge sump

under the action of gravity through three valves at different height.

These valves are operated on the basis of amount of sludge formed in the reactor.

Sewage coming upward through sludge blanket flows into gutter made of FRP. This

effluent is carried in a channel and conveyed to AERATION LAGOON. After this stage

contaminations are removed approximately 50-60% from sewage.

44

Fig. 14 -USAB Reactor

(After Construction)

45

5.9 AERATED LAGOON (FPU I)

Aerated lagoons are relatively shallow lagoons which wastewater is added at a single

point either at the edge or middle of the lagoon and the effluent is removed from another

point. The retention time is a function days as the removal of BOD. The retention time may

vary from 6 to 18 days as the removal of BOD from domestic wastewater varies from 75 to

90 percent.

Oxygen is supplied by means of surface aerators or by diffused aeration units. The

action of the aerators also maintains the solids of the lagoon in suspension. Sewage in this

units gets oxidized in increase in DO level of flow. Two aerated lagoons are used in this

plant, each having area of 13125 sq. m with 4.5 m depth. 9 aerators are installed in each

lagoon at slabs supported on columns. The aerators have the following advantages:

High circulation and mixing capacity

Virtually maintenance free

No risk of clogging, even at intermittent operation or power failure

No spray water.

Fig. 15-Aeration Lagoon

46

5.10 FINAL POLISHING UNIT II

Polishing ponds are used to improve the quality of effluents from efficient anaerobic

sewage treatment plants like UASB reactors, so that the final effluent quality becomes

compatible with legal or desired standard. That residual organic material and suspended

solids concentrations in the digested sewage are reduced, but often the main objective of

polishing ponds is to improve the hygienic quality, measured by the concentration of two

indicator organisms: helminthes eggs and fecal coli forms (FC).

The FC removal is normally the slowest process and for that reason becomes the

main design criterion for a polishing pond. Final polishing unit is usually a shallow earthen

basin of controlled shape, which is designed for treating wastewaters. The ponds are usually

2 to 4 feet deep, although much deeper ponds shave been used quite successfully.

There are two final polishing units in the plant of area70, 000 sq. m with LD of

1.5m+0.5m FB. Base of this unite is made of Mud-Husk.

Fig. 16- Block Diagram of Final polishing unit

47

5.11 CHLORINE COTACT TANK

The treated sewage is disinfected using gas chlorinator all the micro-organism that is

present in water/waste water is not harmful to human beings. Disinfection is the process

meant for removal of those microorganisms, which are harmful (disease causing) to human

beings. In disinfection process, the cell wall of micro-organism is punctured and

deactivation of the enzyme occurs.

A minimum contact time of 15 min is required for the chlorine to destroy the micro-

organism in the treated sewage. Free residual chlorine of 0.5 ppm should be maintained

after 15 min to ascertain complete destruction of the micro-organism.

Chlorine contact Tank Size of chlorine contact tank in the plant is 48.6x30x3.00 m

LD + 0.3 m FB. Maximum amount of micro-organism is removed in this tank and treated

sewage is carried by Final effluent channel to Pandu River.

Fig. 17-Chlorine Contact Tank

48

5.12 GAS HOLDER

SEWAGE GAS TO POWER—

Flaring of Methane produced from the Sewage Treatment Plant is highly hazardous

and detrimental to the environment. Besides, it wastes of a precious source of renewable

energy that can be utilized to run the Sewage treatment plant. Envirex India is a pioneer in

India for indigenously designing, developing and implementing a qualitative system to

efficiently convert the methane from Sewage treatment plants into a renewable and

sustainable source of energy.

Fig. 18 – Gas holder

(During Construction)

49

5.13 FINAL EFFLUENT CHANNEL

A 4.5 m wide channel carried final discharge to Pandu River. This channel is made

of M 25 concrete with the level depth of 1.25 m at RL of 117.41 m.

Fig. 19-Final Effluent Channel

50

5.14 SLUDGE PUMPING STATION

Sludge extracted in reactors is collected in sludge pumping station through FRP

pipes of diameter 10 cm under the action of gravity. Sludge in this unit, is in semi-solid

form which necessitates proper slope of DI pipes from reactors to sludge pumping station.

Powerful pumps should be installed to pump the sludge into filter press building.

5.15 FILTER PRESS BUILDING

One of the most difficult problems today is the disposal of sludge in waste

treatment. Dewatered sludge form traditional dewatering equipment, (i.e. rotary vacuum

drum filters, centrifuges and belt presses), are less acceptable for disposal in landfills and

due to their high moisture content they are not economical feasible. Drying Beds are widely

used these days but they require a considerable amount of land which makes the project

costly. Apart from this it is time taking process and fails in cloudy or rainy weather. The

filter press process results in drier sludge that has proven to be an effective solution. Three

Filter press Machine are used in this project on top of the building (25×15×9m. Solid

particles are collected in trucks under the filter press building. Water separated from sludge

transported to reactors through underground pipes under gravity.

Fig.20 -Filter Press Building

51

5.16 ADMINISTRATIVE CUM LABORATORY BUILDING

Final effluent of the plant should satisfy standards of CPCB. For frequent and

regular testing of influent and effluent, an advanced Laboratory of area 200m2 is present in

the plant for the analysis of BOD, DO, COD and various other characteristics.

Fig. 21-Administrative Cum Laboratory Building

52

6. CONCLUSION

UASB technology used Sewage treatment plant, Bingawan will play very

important role to treat large amount of sewage. It will help in reducing pollution

level in the Ganga in Kanpur district. It is also economic when compared with other

sewage treatment technology like UASB. It will be 2nd

largest STP in India.

It will reduce pollution load on river the Ganga. Apart from this solid sludge

can be used as fertilizers. Many environmental aspect is also associated with this

treatment plants. Aquatic life of river Ganga can be improved.

53

7. REFRENCES

1. Jane Cumberlidge (2009) in land waterways of Great Britain (8th edition

) - Imrey

Laurie Norie and Wilson.

2. Barcelona city history museum water pumping station casa del “aigua”

3. "Evaluation Of Operation And Maintenance Of Sewage Treatment Plants In

India-2007". CENTRAL POLLUTION CONTROL BOARD, Ministry of

Environment & Forests. 2008.

4. "Status of Sewage Treatment in India". Central Pollution Control Board,

Ministry of Environment & Forests, Govt of India. 2005.

5. “Agbar water museum”

6. Sewage disposal and environmental engineering by S.K Garg

7. www.wikipedia.com; www.google.com

8. Environmental engineering II by Saurabh Kumar Soni with KATSON books

9. Environmental engineering by Ardent Publications

10. Some details from the staff of Sewage Treatment Plant, Bingawan, Kanpur

11. Khopkar, S. M. (2004). Environmental Pollution Monitoring and Control. New

Delhi: New Age International.

12. Wastewater engineering: treatment and reuse (4th ed.). Metcalf & Eddy, Inc.,

McGraw Hill, USA. 2003.

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Book Company.

14. Wastewater engineering: treatment and reuse (4th ed.). Metcalf & Eddy, Inc.,

McGraw Hill, USA. 2003.

15. Sharma, Sanjay Kumar; Sanghi, Rashmi (2012). Advances in Water Treatment

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16. EPA. Washington, DC (2000). "Package Plants. "Wastewater Technology Fact

Sheet. Document no. EPA 832-F-00-016.

17. EPA. Washington, DC (1999). "Sequencing Batch Reactors." Wastewater

Technology Fact Sheet. Document no. EPA 832-F-99-073.

18. Wastewater engineering: treatment and reuse (4th Ed.). Metcalf & Eddy, Inc.,

McGraw Hill, USA. 2003