Graduation Project for Sanitary Works

2014Group (11)

Andrew salah faheamAhmed adel said

Environmental Engineering

1- Introduction.

2- Water Supply System.

3- Waste Water System.

.

1- Introduction

Project Data & Preliminary studies :

-(rectangular ) shaped lands for water treatment plant & waste water treatment plant, Dimensins (1:1.5).

-Nile River level (67:00)WTP level (72.00) Locatedat 120 from Nile River WWTP Level (118.50) Located at 5 Km of city.

-From Population & water consumption studies qavg=230 l/c/d Population=27919 capita

2- Water Supply System :Water Treatment Plant Layout

Capacity = 23886m3/day

2- Water Supply System ContinuedWater Treatment Stages :1-Collection Works :shore intakeL.L.P.

2-Purification Works :A.Mixing.B.Coagulation/flocculation. Sedimentation.C.Filtration

3-Distribution Works.Ground reservoir.H.L.P.Elevated tank.Water Distribution network.

2- Water Supply System Continued1-Collection Works:

shore Intake L.L.P

shore intake was chosen based on project given(rayah) …navigable channel high cost of pipe intake (bridge)

Used to Deliver raw water to the WTP through a force main of 120m.

2- Water Supply System Continued :2-Purification works: To get rid of suspended solids and pathogenic bacteria.

A.Mixing Tank B.Clariflocculator

Designed on retention time 1min to ensure adequate mixing between alum and

raw water.

Consists of 2 main parts 1st coagulation/flocculation for 0.5hrs.(to ensure chemical reaction thus floc formation)2nd Sedimentation for 3 hrs(to separate suspended solids form raw water).Depends on size/dentation time/den.of solids

2- Water Supply System Continued :C. Rapid Sand Filter

Used to carry on Filtration process with ROF=150m3/m2/d to ensure removal of remaining particles.

Sedementation action : works as sed, tankBiological action: presence of bacteria help on dec. organic matters

2- Water Supply System Continued :3-Distribution works: we use HLP to deliver waterwith sufficient quantities and adequate pressure.

Ground Reservoir

Store water for Disinfection with chorinemost common dose 1 ppm

Elevated Tank

(Floating) Type for controlling pressure(lowest pressure ) at distribution system and supplying water at peak hours.

2- Water Supply System Continued : Water Distribution Network

- Used System in DesignGRID IRON SYSTEM dead end system

- advantage1- Best basic arrangement of distribution network.2- cheap in some areas3-water flow at any point of system

3- Waste Water SystemWaste water Treatment Plant Layout

We have tried to make the units compacted as possible in order to give the most economic design so that not to waste land areas.

Capacity = 19775 m3/dInfluent : BOD =326ppm Effluent : BOD = 20ppm , TSS= 20ppm

3- Waste Water System Continued :Waste Water Treatment Stages :1-Collection Works :Network of gravity pipes toPump Station.

2-Treatment Works :screening stage Primary treatmentsecondary treatment

3-Disposal & Sludge handling:Gravity thickenerDrying BedsTo irrigation Zone.

3- Waste Water System Continued :1-Collection Works: Network of Gravity Pipes

-Gravity pipes should be partially full to avoid anaerobic reactions and production of harmful gases and smell( H2S & CH4).

-Manholes are placed at specific locations according to Egyptian code.

3- Waste Water System Continued :Pump Station

Pump Station was chosen at the lowest elevation in the city4 dry Pumps(2 Operating + 2 Standby) to deliver water to the WWTP through a Force main of 5 Km length.

3- Waste Water System Continued :2-Treatment Works:

Inlet Chamber, Screens & Grit Removal

Primary Sedimentation Tank

-- Screening & Primary Treatment :

Used to get rid OF large Solids, Grit & Sand.

To get Rid of 65% of SS. & 35% of OM.Circular type PST with retention time 3 hrs

3- Waste Water System Continued :-- Secondary Treatment :Trickling filter Final Sedimentation

Tanks

Design is based on :attached growth where Bactria grow on surface and feed on OM

Design is based on : Water settle in this tank to get rid of reaming solids withSolids loading rate = 2.5 Kg/m2.hr.

3- Waste Water System Continued :3- Disposal & Sludge handling SystemGravity Thickener Drying Beds

Decreasing volume of sludge to half it’s volume by decreasing water content from 95% to 90%. Retention time = 2 days.

Simple operation.Low maintenance & affected by climate.

Any Questions ?!!Thank you