Design of 125 kld sewage treatment plant at dundigal village, medchal distrct, telanagana state ijae

Scientific Journal of Impact Factor (SJIF): 4.72

e-ISSN (O): 2348-4470 p-ISSN (P): 2348-6406

International Journal of Advance Engineering and Research Development Volume 4, Issue 11, November -2017

Design of 125 KLD Sewage Treatment Plant at Dundigal Village, Medchal Distrct, Telanagana State Dr.Vajja Varalakshmi1, Dr.K.Venkateswara Reddy2, N.Krishna Rao2, T.Abhiram Reddy3 1,3,4

2

Department of Civil Engineering, Marri Laxman Reddy Institute of Technology and Management, Dundigal Village&Mandal, Hyderabad, Telanagana State

Principal, Marri Laxman Reddy Institute of Technology and Management, Dundigal Village&Mandal, Hyderabad, Telanagana State

Abstract — Dundigal Village of Medchal District, Telangana State does not have proper drainage system. The house holds waste water (grey water) joining directly into the lake creating the pollution. So it is required to construct a sewerage treatment plant to collect and treat grey water before entering the lake to decrease the lake pollution. The treatment operations are done by various methods in order to reduce its organic content. This paper focuses on the Designing of Sewerage Treatment Plant for 4 colonies of Dundigal area. In one day the total sewage generated was estimated 125 KLD. The various components of sewage treatment plant are Grey water collecting tank, Bar screen chamber, SBR Tank, Equilisation tank and Treated water collecting tank. It is proposed to design the various components of sewage treatment plant considering the various standards and permissible limits of treated sewage water.

The treated water will be supplied for irrigating the crops and the sludge which is generated after the treatment will be used as manure, so it increases the fertility of soil. Also reduce the ground water usage.

Keywords- Grey water, sequential batch reactor, Sewarage Treatment Plant; Design approach I.

INTRODUCTION

Sewage treatment plant (STP) plays an important role for the mankind. The main function of these plants is to make the water of the sewage clean that comes from home. The treatment of sewage water has become the need of the hour as it stops spreading the diseases and illness caused by the sewage water. It helps society in making the water as well as environment clean.

In Dundigal Village & Mandal of Telangana State, it is observed that there is severe crisis of drinking water as well as there is problem of disposing the sewage water due to lack of storm water drainage system in the village. Some colonies near the lake are disposing their waste directly into the lake. It causing a severe threat to the water chemistry, micro-habitat, causing a variety of diseases, increased evapotranspiration, fishing problems etc. therefore it is necessary to create a proper sewer lines to collect a grey water from the colonies and treated the this grey water before entering it into the lake and supplied to agricultural and gardening purpose. Therefore the treatment plant is designed to cover four colonies namely Munnur basthi, Kurma basthi (fully) and Gollola basthi and Pittala basthi (partly) covering nearly 200 houses near the lake.

II. LITERATURE REVIEW Activated sludge process, oxidation ponds, aerated lagoons and oxidation ditches are the commonly adopted suspended growth biological treatment systems. However, the flexibility in design, process and cost Sequencing Batch Reactor (SBR) is best defined process. (Irvine et al., 1979). Demoulin et al., 1997; Keller et al., 2000 used SBR for nutrient removal. Hersbrun, 1984; Ng, 1987; Ng and Chin, 1986 used for treatment of industrial and hazardous wastes effectively.

Lin S.H. and Cheng K.W., (2001) treated the municipal sewage with SBR process. SBR reactor was divided into 3 equal compartments containing Two perforated baffle plates having 2-mm holes. From this Reactor the COD and BOD removal observed was 93.6% and 91.8 % respectively. Klimiuk and Kulikowska (2006) carried out the SBR study to treat the municipal landfill leachate. The study was devoted to nitrogen removal from leachate by activated sludge treatment in SBR. The rate of ammonium removal and nitrification rate in the SBR cycle were estimated. The concentration of ammonium in the effluent did not exceed the value of 1 mgNNH4/dm3 at sludge ages above 20d and the ammonium removal rate changed from 5.38 mg NNH4/ g VSS.h to 7.36 mg NNH4/g VSS.h, while the nitrification rate changed from 0.75 mg NNO3/g VSS.h to 0.99 mg NNO3/g VSS.h.

Kulikowska et al. (2007) aimed to estimate the BOD5 and COD removal efficiency and biomass yield coefficient in SBR treating landfill leachate.. It was observed that there is no change in BOD removal efficiency due to change in HRT but @IJAERD-2017, All rights Reserved

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International Journal of Advance Engineering and Research Development (IJAERD) Volume 4, Issue 11, November-2017, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406 COD removal efficiency was affected by about 4 to 5 % in both conditions. Also there is significant increase in biomass decay rate, as it was observed fivefold increase in aerobic condition as compared to aerobic-anaerobic phase (0.006 d -1 to 0.032 d-1). Due to lower biomass aerobic system was considered to be optimal for municipal leachate. Freitas et al.

(2009) proposed that short SBR cycles select and maintain a robust and active biomass, able to cope with typical disturbances occurring in wastewater treatment plants. In order to test this hypothesis, an SBR system was subjected to COD, N and P shock loads. It was shown that the sludge enriched in the SBR operated with short cycles was able to rapidly recover from the tested disturbances.COD and N removal recovered within 1–2 days for shock loads of 10 times the standard concentration. . It was concluded that SBR operated with short cycles led to a robust sludge that was able to respond well to shock loads.

III. Methodology

SBR: Sequencing Batch Reactor , PSF: Pressure sand filter,ACF Activated carbon filter Fig.1 Flow Diagram IV. Point To Be Considered In Design Following points are considered during the design of sewage treatment unit  The maximum waste water generation shall not exceed 115KLD  The proponent shall provide Sewage Treatment Plant (STP) of 125 KLD capacity consisting of Grey water collecting Unit, Bar Screen Chamber, Equilisation tank, Sequencing Batch Reactor (SBR) tank, Treated water collection Tank  The treated wastewater shall be recycled for agricultural and gardening purposes. The excess treated wastewater is to be discharged into Public sewer line.  All the units of the STP shall be impervious to prevent ground water pollution. STP shall be operated in a closed circuit so as to avoid smell nuisance.  Treated effluents (i.e. outlet of STP) shall comply with inland surface water discharge standards.  Self scaling velocity should develop at every place and stage  The design of the treatment units should be economical; easy in maintenance should offer flexibility in operation @IJAERD-2017, All rights Reserved

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International Journal of Advance Engineering and Research Development (IJAERD) Volume 4, Issue 11, November-2017, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406 V. Design of Individual Units 5.1 Receiving chamber: Receiving chamber is the structure to receive the raw sewage collected through under ground sewage system from the village. It is a rectangular shape tank constructed at the entrance of the sewage treatment plant. The main sewer pipe is directly connected with this tank.

Average water supply per day =140000lit =0.18 mld Average sewage = 85% of supplied water =0.85x0.14 =0.119mld = 119 KLD ͌ 125 KLD Total quantity of water requirement for the Dundigal people is 1,40,000 lit/day. By considering 85 % of the water supplied will be converted in to sewage i.e. 119 KLD. Wastewater generated from the proposed project will be treated in an STP of 125 KLD. Detailed design write up of the STP is in the following section.

The sewage generated during the operation phase will be treated up to the tertiary level in Sewage Treatment Plants (STP) The entire (100%) treated sewage from STP of 125KLD capacity will be recycled/ reused for agricultural and gardening purposes in the Dundigal village.

Average. Sewage per hour = 125/24 = 5.20 �3/hr Peak Factor = 3 Design Flow capacity = 5.20×3 =15.6 m3/hr. =0.0043m3/sec Sizing calculation for collection pit: Retention time required =4h Average design flow =15.6m3/h Capacity of collection sump =4x15.6 =62.4m3 Assume liquid depth =5m Area required for collection pits =62.4/5 =12.48 m2 Let it is a rectangular tank Now 12.48 = bd d=5.5m, b= 2.5m, l=5 Volume of the pit provided =68.75m3 5.2 Bar screen chamber: Max Flow = 125 KLD Detention Time = 6.0 min Bar Screen Chamber Volume = 1.5 m3 Let Side water depth (SWD) be 1.0 m BSC Size = 1.0 m x 1.0m x 1.50 m Screen is made out of MS Flat of Size 10mm x 50mm (10mm facing the flow) Clear spacing between bars = 20mm Inclination of bars with horizontal = 60° (For Manual Cleaning) �max = 0.0043 �3/sec Assumption; Shape of bar = M.S. Flats Size = 10 mm X 50 mm Clear spacing between the bars = 20 mm. inclination of bars = 60 deg.

Assume avg. Velocity to sewer = 0.8 m/sec At peak flow, net inclined area required = 0.03 9/0.8 = 0.048 sq. m Gross inclined area = 0.048 x 1.5 = 0.072 sq. m gross vertical area required = 0.072 x sin80 = 0.070 sq. m Provide submergence depth = 0.3 m Width of channel = 0.070/0.3 = 0.23 m ≈ 0.30 m Provide 20 bars of 10 mm x 50 mm at 20 mm clear spacing. Screen chamber will be 60 cm wide.

Bar Screen Chamber Size = 1.0 m x 1.0m x 1.50 m 5.3 Equalization tank: The flow from the bar screen chamber is let into the equilisation tank. This tank is provided to even out the flow variation and to provide a continuous feed into the secondary biological treatment units.

Design flow : 1,40,000lit/day @IJAERD-2017, All rights Reserved

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International Journal of Advance Engineering and Research Development (IJAERD) Volume 4, Issue 11, November-2017, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406 Average flow: 20 hours Provided equilisation tank with HRT of 6 hours (holding capacity) Hence required volume of the tank = 37.5m3 Provide a tank of 39,000 liter capacity Equalization tank dimension = 3.33m x 5.0m x 4.0m Free board should be 1.5m 4.4. SBR Flow = 125 KLD BOD after treatment <10mg/l Assumption: F/M Ratio : 0.10 (between 0.10-0.18) MLSS : 8000MG/L when tank is full Total BOD Load : 46kg/day No. of Reactor : 2 Nos No. of Cycles per reactor: 3 Nos Deccant fraction of aeration tank : 60% Fill volume per batch :55 cumecs Recommended value of the reactor :165cumec Overall volume of SBR :165 M3 Hence provide SBR tank of capacity 1,65,000lit/day The aeration tank size required will be of dimension 3.6m×5m×4m Free board should be 0.5m 5.5 Calculation of air volume BOD5 after treatment <10mg/l BOD5 loading :350mg/l Total BOD5 load :(125×1000×350)/1000000 kg/day Total BOD5 load :44kg/day BOD5 load in kg/day in the aeration tank:44kg/day (2kgs of axygen is required for every kg of BOD5 to be removed) % of oxygen in air :0.21 Density of air :1.2 Air volume required per day :365m3 of O2/Day No.of hours of oxygenation :10.5 =35m3/hr Diffuser transfer efficiency = 35/0.27 =130 m3/hr (27% for 4.5 m submergence) Hence, air volume required in aeration tank :130+30% extra :169m3/hr Equilisation 20% of air volume of aeration tank :34m3/hr Sludge holding tank+decant tank+treated water tank:34m3/hr Therefore total air requirement in cum/day :240m3/hr

5.6 Pressure sand filter Pressure sand filter with various grades of pebbles and sand media help in the removal of residual suspended solids. The filter will be operating in the pressure range of 3-3.5 kg/cm2 Assuming a loading rate of 6.0 m3/ hr Design flow = 125 m3/day and considering 20 hr/day of operations of PSF The recommended PSF dimension is 0.8m diameter with 1.5 m height sand media over layer, under drainpipe, laterals face piping.

5.7 Activated carbon filter Design flow = 125 m3/day Loading rate =12 cumec/m2/hr Provide an activated carbon filter of dimension is 0.8m diameter with 1.5 m height with carbon filter media with under drainpipe, lateral face piping.

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International Journal of Advance Engineering and Research Development (IJAERD) Volume 4, Issue 11, November-2017, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406 5.8 Chlorination: The filtered water is further chlorinated through an online automatic chlorination system with electronic dosing pump for disinfection. Provide one number automatic chlorinator with electronic metering pump to ensure the residual chlorine level to be less than 2 ppm for disinfect ion as that it will not affect the plantations. The chlorinator shall be coupled with the filter outlet.

5.9. Final collection tank: Final Collection Tank: Detention time = 11.5 Hrs Volume of Final collection tank = 70.0 m3 Final Collection tank dimension = 4.5m x 5.0m x 3.5m 5.10 Pumps: A.provide 2 Nos sewage transfer pumps (one working and one standby) Capacity:6.0KLH@15m head Type : centrifugal pumps Solid handling size upto 10mm Purpose: to pump the sewage from the equilisation tank to SBR Tank B. Provide 1 No sludge transfer Capacity:3KLH/hr@15m head Type :centrifugal pump Solid handling size upto 25mm Purpose: to pump the sludge from SBR Tank to sludge drying beds C. Provide 1 No sludge transfer Capacity:10KLH/hr@30m head Type :centrifugal pump, self priming Solid handling size upto 5mm Purpose: to pump the treated effluent from the pre-filtration tank through the pressure sand filter and activated carbon filter VI. CONCLUSIONS The wastewater generated from Dundigal Village and mandal of Medchal District, Telanagana State is currently treated by 125 KLD sewage treatment plant. The treatment is carried out by SBR technology which is the cyclic activated sludge treatment process. In the SBR Multiple Sequencing batch reactors are provided to treat the wastewater in batches.

Sequencing batch reactors will be operated to oxidize carbonaceous Bio chemical Oxygen Demand (BOD), nitrify the ammonia and denitrify to reduce total nitrogen to a level that meets the permit limits. The treated water from SBR is pumped through the Pressure sand filter and Activated carbon filter for removal of suspended solids, final polishing and removal of any traces of colour. For HVAC purpose part of the treated water is passed through Softener for achieving the desired hardness reduction. The effluent is then disinfected with Chlorine by intermittent dosing system. The treated sewage can be used for chillers and flushing purposes. Excess sludge from SBR tank is pumped out periodically to the Sludge holding tank and then fed in to the Filter press for dewatering and drying during decanting phase.

S.No

Table:1 Important units of the sewage treatment plant Name of the unit Size in m

1

Bar screen chamber

1.0m×1.0m×1.50m

2

Equilisation tank

3.33m×4.0m×5.0m

3

Sequencing Batch Reactor (SBR)

3.6m×5.0m×4.0m

4

Decant tank

4.2.0m×5.0m×4.0m

5

Final treated water tank

1.5m×5.0m×4.0m

6

Sand bed filters

.8m dia and 1.5mm height

7

Activated carbon filter

.8m dia and 1.5m height

8

chlorinator

100liters capacity

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International Journal of Advance Engineering and Research Development (IJAERD) Volume 4, Issue 11, November-2017, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406

Fig.2 Plan and Section of 125 KLD STP at Dundigal Village VI. ACKNOWLEDGEMENTS I would like to thank Science & Technology for women under Science for Equity, Empowerment & Development (SEED) Division –DST for giving financial support for this work.

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[2] Freitas Filomena, Margarida F. Temudo , Gilda Carvalho , Adrian Oehmen , Maria A.M. Reis, “Robustness Of Sludge Enriched With Short SBR Cycles For Biological Nutrient Removal”, Bioresource Technology Vol.100, pp.

1969–1976, 2009.

[3] Hersbrun, P. A., “Treatment Of Hazardous Waste In A Sequencing Batch Reactor,” Proceedings of 39th Annual Industrial Waste Conference, Purdue University, West Lafayette, Indiana, USA, pp 385-393, 1984.

[4] Irvine, R. L., Miller, G., and Bhamrah, A. S., “Sequencing Batch Treatment Of Wastewater In Rural Areas,” Journal Water Pollution Control Federation, vol.51(2), pp.244-254, 1979.

[5] Keller, J., Watts, S., Battye-Smith, W., and Chong. R., “Full-Scale Demonstration Of Biological Nutrient Removal In A Single Tank SBR Process” Proceedings of the 2nd International symposium of International Water Association (IWA) on Sequencing Batch Reactor Technology, 10-12, July, Narbonne, France, pp 380-388, 2000.

[6] Klimiuk E., Kulikowska D., “The Influence of Hydraulic Retention Time and Sludge Age on the Kinetics of Nitrogen Removal from Leachate in SBR”. Polish J. Environ. Stud. Vol. 15(2), pp. 283-289, 2006.

[7] Kulikowska Dorota , Klimiuk Ewa , Drzewicki A., “BOD5 and COD Removal And Sludge Production In SBR Working With Or Without Anoxic Phase”. Bioresource Technology Vol. 98, pp. 1426–1432,2007.

[8] Lin S.H., Cheng K.W., “A New Sequencing Batch Reactor For Treatment Of Municipal Sewage Wastewater For Agricultural Reuse”. Desalination Vol.133, pp. 41-51, 2001.

[9] Ng, W. J. and Chin, K. K., “Biological Treatment for Pig Farm Wastewater”. Proceedings of the Regional Symposium on Management of Industrial wastes in the Asia & Pacific, ENSEARCH, Kualalumpur, Malaysia, 17-18 November, pp 123-127. 1986.

[10] Ng, W. J., “Treatability Of Textile Finishing Effluent – SBR Method”. Internal report, Environmental Engineering Laboratory, National University of Singapore, Singapore. 1987. @IJAERD-2017, All rights Reserved

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