Ahs Mrw00 SEO-nf100 Revd Asb

8/18/2019 Ahs Mrw00 SEO-nf100 Revd Asb

1/13

M1145-A40215REV

D SH/SH END

1/13N of SH

13HS M RW 00 SEO-NF100

COMMENTS :

Sign.N.

Sign.N.

DSign.N. ALLETRU PAUL ORIOU 2010/09/20 AS BUILT ASB

C Sign.N. ALLETRU PAUL ORIOU 2010/02/17 APPROVED AS PER LETTER S/LI/ALSTOM-2226 DATED08/02/2010 GFE

B Sign.N. ALLETRU PAUL PASCAL 2009/08/12 UPDATED ACCORDING TO VARIATION ORDER C-020 GFR

ASign.N. RENTROP

AUGERDELAGE

BINDELE 2005/03/01 FIRST ISSUE GFE

R E V

ETABLI

ESTABLISHEDVERIFIE

CHECKEDAPPROUVEAPPROVED

DATE MODIFICATIONS STAT

Approved Approved as noted Returned for correction For information

Date : ………………………….. Signature : …………………………….

LAHMEYER INTERNATIONAL

GOVERNMENT OF THE REPUBLIC OF THE SUDANMINISTRY OF IRRIGATION AND WATER RESOURCES

MEROWE DAM PROJECT IMPLEMENTATION UNIT

MEROWE DAM PROJECT10 x 140MVA

CONTRACTS 3A, 3B, 3C, 3E

ENGINEER: CONTRACTOR:

DOMESTIC SEWAGE SYSTEM

PROCESSING NOTICE

SCALE1/1

Subcontractor:

INTERNAL USE

Ce document propriété de ALSTOM ne doit pas être utilisé, copié ou communiqué à des tiers sans son autorisationThis document is the exclusive property of ALSTOM and shall not be used, copied or communicated to third parties without their prior authorization

Power EnvironmentHydro

22/09/2011

V. Paul S/LI/ALSTOM-3186


2/13

M-1145-A40215.2/D

TABLE DES MODIFICATIONS / MODIFICATIONS TABLE

REVETABLI

ESTABLISHED VERIFIECHECKED

APPROUVEAPPROVED DATE MODIFICATIONS STAT.

A RENTROPAUGERDELAGE

BINDELE 2005/03/01 FIRST ISSUE GFE

B ALLETRU PAUL PASCAL 2009/08/12 UPDATED WITH VARIATION ORDER C-020 GFR

C ALLETRU PAUL ORIOU 2010/02/17APPROVED AS PER LETTER S/LI/ALSTOM-2226DATED 08/02/2010

GFE

D ALLETRU PAUL ORIOU 2010/09/20 AS BUILT ASB


3/13

M-1145-A40215.3/D

TABLE OF CONTENTS

1 PURPOSE OF THE DOCUMENT........................................................................................................ 4

2 REFERENCE DOCUMENT.................................................................................................................. 4

2.1 CONTRACT DOCUMENTS .................................................................................................................... 4 2.2 ASSOCIATED DOCUMENTS ................................................................................................................. 4

3 GENERAL DESCRIPTION OF THE DOMESTIC SEWAGE SYSTEM ........................................ 4

4 SYSTEMS MANAGEMENT AND OPERATION PRINCIPLES ..................................................... 5

4.1 DOMESTIC SEWAGE TANK (00SEO001BA)....................................................................................... 5 4.2 DOMESTIC SEWAGE PUMPS (00SEO001/002PO)............................................................................... 5 4.3 SEWER SHAFT (91SEO001BA).......................................................................................................... 7

4.4 SEWER SHAFT PUMPS (91SEO001/002PO)........................................................................................ 7 4.5 DOMESTIC SEWAGE PIPING ................................................................................................................ 9 4.6 FLUSHING CONNECTIONS................................................................................................................... 9

4.6.1 Flushing connections for pumps ................................................................................................ 9 4.6.2 Inspection pits.......................................................................................................................... 10

4.7 VALVES............................................................................................................................................ 10

5 SYSTEM CONTROL PRINCIPLES .................................................................................................. 11

5.1 REMOTE CONTROL ........................................................................................................................... 11 5.2 MAINTENANCE AND MANUAL CONTROL ......................................................................................... 11 5.3 ELECTRICAL INTERFACES TO OTHER SYSTEMS................................................................................ 11

6 INTERFACE DATA ............................................................................................................................. 12 6.1 INSTRUMENTATION .......................................................................................................................... 12


4/13

M-1145-A40215.4/D

1 PURPOSE OF THE DOCUMENT

The purpose of this document is to describe the general function, the maincomponents, the control principles and the interfaces to other systems of thedomestic sewage disposal system pertaining to the MEROWE project.

2 REFERENCE DOCUMENT

2.1 CONTRACT DOCUMENTS

Particular Technical Specification Contract 3E - §36

2.2 ASSOCIATED DOCUMENTS

AHS MRW00 SEO-SP100: DOMESTIC SEWAGE SYSTEM - FLOW DIAGRAM

AHS MRW00 SEP-SP100: DRINKING WATER SUPPLY SYSTEM - FLOWDIAGRAM

AHS MRW00 ITY-MS100: PIPING SPECIFICATION

3 GENERAL DESCRIPTION OF THE DOMESTIC SEWAGE SYSTEM

Domestic sewage from the sanitary facilities of the administration and servicebuilding, the power house, the substation control building and the service area iscollected in the domestic sewage tank at level 241,500 m. Sludge and filterbackwash water originating from the drinking water system is directed into this tank.Two submersible wastewater pumps (one duty, one stand by) of at least 25 m³/hcapacity transfer the wastewater via a pressure pipe to the sewer shaft.

Domestic sewage from the supporting facilities is collected in the sewer shaft atlevel 257,650 m.

From the sewer shaft, the effluents are directed to the sewage treatment plant viatwo submersible wastewater pumps (one duty, one stand by) of at least 25 m³/hcapacity.

The main components of the domestic sewage disposal system are:

- Domestic sewage tank (00SEO001BA);


5/13

M-1145-A40215.5/D

- Submersible domestic sewage pumps (00SEO001/002PO);

- Sewer shaft (91SEO001BA);

- Sewer shaft pumps (91SEO001/002PO);

- Domestic sewage pressure pipe;

- Six inspection pits with flushing connections;

- All necessary valves and instrumentation.

4 SYSTEMS MANAGEMENT AND OPERATION PRINCIPLES

4.1 DOMESTIC SEWAGE TANK (00SEO001BA)

The domestic sewage tank (00SEO001BA) is a concrete basin integrated into theservice and administration building at level 241,500 m. It is accessible via a manholefrom level 247,600 m.

The usable volume is 20 m³.

It is equipped with:

- Support, guiding rope and pressure pipe to install two submersible sewage

pumps;

- A basket with a mesh size equal to the free passage of the pump (> 75 mm) at theinlet. This is only a safety device to protect the pumps from extraordinary bigparts, which are normally not expected in the network;

- A vent pipe going outside the building.

A slight slope at the bottom of about 4 % directs domestic sewage to thesubmersible pumps.

4.2 DOMESTIC SEWAGE PUMPS (00SEO001/002PO)

Two pumps 00SEO001PO and 00SEO002PO are installed as domestic sewagepumps to transfer domestic sewage from the domestic sewage tank 00SEO001BAto the outdoor sewage network.

These are submersible centrifugal pumps specially designed for wastewater. Theyare placed inside the domestic sewage tank 00SEO001BA.


6/13

M-1145-A40215.6/D

The pumps are equipped with special impellers allowing a free passage of at least75 mm.

This enables to do without strainers or rakes, which would require maintenance.

The pumps are connected to the pressure pipe using a specially designed bend.The weight of the pump acts as a seal between the pump and the bend. Formaintenance, each pump can be removed and repositioned without emptying thedomestic sewage tank.

One pump is working in normal operation mode and the other pump is working instand-by operation mode. The permutation of the pump is automatic, while thepumps electric supply is ensured from the auxiliary board 20LKA001TB.

In the tank 00SEO001BA:

- An emergency low level detector 00SEO001SN detects a low level in the tank(242,500 m). Emergency stop of all pumps in operation by the local control board00SEO001CR.

- A low level detector 00SEO002SN detects a low level in the tank (242,800 m).The pump in operation is stopped by the local control board 00SEO001CR.

- A high level detector 00SEO003SN detects a high level in the tank (244,600 m).The normal pump is started by the local control board 00SEO001CR.

- A very high level detector 00SEO004SN detects a very high level in the tank

(245,600 m). Both pumps are started by the local control board 00SEO001CR.

- An emergency very high level detector 00SEO005SN detects a very high level inthe tank (246,500 m). The drinking water filtration and purification unit00SEP001FI is stopped by the local control box 00SEP001CR.

The following table provides a summary of the main operation principles:

Sensor identification Automatic consequences

00SEO005SN↑ : Stop of 00SEP001FI by the localcontrol box 00SEP001CR

00SEO004SN↑ : Start of both pumps by the localcontrol board 00SEO001CR

00SEO003SN↑ : Start of one pump by the local controlboard 00SEO001CR

00SEO002SN↓ : Stop of the pumps in operation bythe local control board 00SEO001CR

00SEO001SN↓ : Emergency stop of the pumps inoperation by the local control board

00SEO001CR


7/13

M-1145-A40215.7/D

Note : ↑ represents a level rising in the tank↓ represents a level decreasing in the tank.

At the outlet of the two pumps 00SEO001PO and 00SEO002PO, two manometers,

respectively 00SEO001LP and 00SEO002LP, allow the local verification of thepressure levels.

Two pressure logical sensors, respectively 00SEO001SP and 00SEO002SP, ensurethe hydraulic supervision of the flow presence at the outlet of the pumps.

The pumps 00SEO001PO and 00SEO002PO can be isolated for maintenancepurpose respectively by the valve 00SEO002VE as well as 00SEO004VE. Each ofthese valves is normally open.

Two non-return valves 00SEO001VE and 00SEO003VE prevent respectivelycounter flows on the pumps 00SEO001PO and 00SEO002PO.

4.3 SEWER SHAFT (91SEO001BA)

The sewer shaft (91SEO001BA) is a concrete basin recovering sewage water fromSupporting Facilities and from Spillway. It is accessible via a manhole from level261,850 m.

The usable volume is 7 m³.

It is equipped with:

- Support, guiding rope and pressure pipe to install two submersible sewagepumps;

- A basket with a mesh size equal to the free passage of the pump (> 75 mm) at theinlet. This is only a safety device to protect the pumps from extraordinary bigparts, which are normally not expected in the network;

- A vent pipe going outside the pit.

4.4 SEWER SHAFT PUMPS (91SEO001/002PO)

Two pumps 91SEO001PO and 91SEO002PO are installed as sewer shaft pumps totransfer domestic sewage from the sewer shaft 91SEO001BA to the sewagetreatment plant.


8/13

M-1145-A40215.8/D

These are submersible centrifugal pumps specially designed for wastewater. Theyare placed inside the sewer shaft.

The pumps are equipped with special impellers allowing a free passage of at least75 mm.

This enables to do without strainers or rakes, which would require maintenance.

The pumps are connected to the pressure pipe using a specially designed bend.The weight of the pump acts as a seal between the pump and the bend. Formaintenance, each pump can be removed and repositioned without emptying thesewer shaft.

One pump is working in normal operation mode and the other pump is working instand-by operation mode. The permutation of the pump is automatic, while the

pumps electric supply is ensured from the auxiliary board 91LKA001TB.

In the sewer shaft 91SEO001BA:

- An emergency low level detector 91SEO001SN detects a low level in the tank(258.050 m). Emergency stop of all pumps in operation by the control box91SEO001CR and information is monitored by 20KKM controller.

- A low level detector 91SEO002SN detects a low level in the tank (258.200 m). Allpumps in operation are stopped by the control box 91SEO001CR and informationis monitored by 20KKM controller.

- A high level detector 91SEO003SN detects a high level in the tank (258.750 m).The normal pump is started by the control box 91SEO001CR and information ismonitored by 20KKM controller.

- A very high level detector 91SEO004SN detects a very high level in the tank(259.300 m). Both pumps are started by the control box 91SEO001CR andinformation is monitored by 20KKM controller.

- An emergency very high level detector 91SEO005SN detects a very high level inthe tank (259.450 m). An alarm is transmitted to the control room and both pumpsare started by the control box 91SEO001CR and information is monitored by

20KKM controller.

The following table provides a summary of the main operation principles:

Sensor identification Automatic consequences

91SEO005SN↑ : Emergency start of both pumps bythe local control board 91SEO001CR

91SEO004SN↑ : Start of both pumps by the localcontrol board 91SEO001CR


9/13

M-1145-A40215.9/D

91SEO003SN↑ : Start of one pump by the local controlboard 91SEO001CR

91SEO002SN↓ : Stop of the pumps in operation bythe local control board 91SEO001CR

91SEO001SN↓ : Emergency stop of the pumps inoperation by the local control board91SEO001CR

Note : ↑ represents a level rising in the tank↓ represents a level decreasing in the tank.

At the outlet of the two pumps 91SEO001PO and 91SEO002PO, two manometers,respectively 91SEO001LP and 91SEO002LP, allow the local verification of thepressure levels.

Two pressure logical sensors, respectively 91SEO001SP and 91SEO002SP, ensurethe hydraulic supervision of the flow presence at the outlet of the pumps.

The pumps 91SEO001PO and 91SEO002PO can be isolated for maintenancepurpose respectively by the valve 003VE as well as 004VE. Each of these valves isnormally open.

Two non-return valves 001VE and 002VE prevent respectively counter flows on thepumps 91SEO001PO and 91SEO002 PO.

4.5 DOMESTIC SEWAGE PIPING

Domestic sewage piping is cast iron according to piping specification AHS MRW00ITY-MS100, except from Supporting Facilities to Sewer Shaft (PVC).

The piping has continuous slope.

In order to avoid sedimentation during stand still, the pipe diameter is selected toassure a minimum velocity of 0,8 m/s.

4.6 FLUSHING CONNECTIONS

4.6.1 Flushing connections for pumps

A water tap ND 50 with a hose connection and a hose is installed near the pumps.Flushing connections with ND 50 hose connections is supplied to enable flushingeach pump backwards as well as the pressure pipe in case of blockage or prior todismantling of the system.


10/13

M-1145-A40215.10/D

4.6.2 Inspection pits

Two inspection pits with one ND 50 hose flushing connection each are built toenable flushing the pressure pipe in case of blockage or prior to dismantling of the

system between domestic sewage tank 00SEO001BA and the sewer shaft91SEO001BA.

Four inspection pits with one ND 50 hose flushing connection each are built toenable flushing the pressure pipe in case of blockage or prior to dismantling of thesystem between the sewer shaft 91SEO001BA and the sewage treatment plant.

Flushing will be done via hydrants located on the fire fighting pipe which is installedalong the sewage pipe.

4.7 VALVES

All valves used in the domestic sewage system are gate valves to avoid anyobstacles that may lead to a blockage.

All check valves are also of “free flow” type without restrictions or obstacles whenopen.


11/13

M-1145-A40215.11/D

5 SYSTEM CONTROL PRINCIPLES

5.1 REMOTE CONTROL

See documents AHS MRW00 SEO-MS200 and AHS MRW91 SEO-MS200“DOMESTIC SEWAGE SYSTEM – FUNCTIONAL ANALYSIS”.

5.2 MAINTENANCE AND MANUAL CONTROL


5.3 ELECTRICAL INTERFACES TO OTHER SYSTEMS



12/13

M-1145-A40215.12/D

6 INTERFACE DATA

Interface Maximum instantaneous

flow rate

Average flow rate

Domestic sewage inFlow by gravity intodomestic sewage tank 20m³

50 m³/d

Domestic sewage out 25 m³/h (about 45 m³/h incase both pumps operatein parallel)

50 m³/d

Sludge (0,5-1% solids)from sedimentation tankfrom the drinking waterunit to the domesticsewage tank by gravity

30 m³/h 4,5 m³/d

Back wash waste waterfrom the drinking waterunit to the domesticsewage tank by gravity

10 m³/h 1,5 m³/d

Drinking Water fromdrinking water network

15 m³/h Maintenance andcleaning only

Electrical power Max 17 kW per pump

6.1 INSTRUMENTATION

Sensor Designation Connection to Purpose

00SEO001LP 00SEO001PO pumpoutlet pressureindicator

/ 00SEO001PO pumplocal pressure indication



00SEO001SP 00SEO001PO pumpoutlet pressure logicalsensor

00SEO001CR 00SEO001PO pumpautomatic control andrunning supervision



00SEO001SN Domestic sewage tank00SEO001BAemergency low levelsensor

00SEO001CR Domestic sewagetransfer pumps control

00SEO002SN Domestic sewage tank00SEO001BA lowlevel sensor


00SEO003SN Domestic sewage tank00SEO001BA high

level sensor



13/13

M-1145-A40215.13/D

00SEO004SN Domestic sewage tank00SEO001BA veryhigh level sensor


00SEO005SN Domestic sewage tank00SEO001BA

emergency very highlevel sensor

00SEP001CR Drinking water filtrationand purification unit

control









91SEO001SN Domestic sewage tank91SEO001BAemergency low levelsensor


91SEO002SN Domestic sewage tank91SEO001BA lowlevel sensor


91SEO003SN Domestic sewage tank91SEO001BA high

level sensor


91SEO004SN Domestic sewage tank91SEO001BA veryhigh level sensor


91SEO005SN Domestic sewage tank91SEO001BAemergency very highlevel sensor


Ahs Mrw00 SEO-nf100 Revd Asb

Documents

Transcript of Ahs Mrw00 SEO-nf100 Revd Asb