SOP for Preventive Maintenance of Effluent Treatment Plant EN-55

The objective of this Standard Operating Procedure for preventive maintenance of Effluent Treatment Plant is to outline the steps and guidelines for conducting preventive maintenance on an Effluent Treatment Plant (ETP) to ensure its efficient operation, compliance with environmental regulations, and proper treatment of wastewater.

SOP for Preventive Maintenance of Effluent Treatment Plant

• OBJECTIVE:
  • To lay down the procedure for preventive maintenance of Effluent Treatment Plant.
• SCOPE:
  •  This procedure is applicable to preventive maintenance of Effluent Treatment Plant installed in the premises.                                                                    
• RESPONSIBILITY:
  •  Technician/ Operator-Engineering shall be responsible for proper execution of preventive maintenance of Effluent Treatment Plant as per SOP.
  •  Engineering – Head shall be responsible for reviewing the SOP and for ensuring proper execution of preventive maintenance of Effluent Treatment Plant
• ACCOUNTABILITY:
  •  Head of department- Engineering shall be accountable for SOP.
• DEFINITION:
  •   Preventive Maintenance: The preventive maintenance of Effluent Treatment Plant describes all scheduled work done on a routine, predefined basis to maintain facilities, equipment, utilities and devices in good status in order to ensure reliable performance.
• PROCEDURE:   
  • Preventive maintenance of Effluent Treatment Plant shall be executed as per the SOP No.: SOP/EN/XXXYYY – Execution of Preventive Maintenance.
  •  Ensure that the spare parts shall be available at the time of preventive maintenance.
• Mechanical preventive maintenance of Effluent Treatment Plant;
• Checking of pumps.
  • Check for any leakages from the mechanical seal, if leakage is found then rectify the leakage by following method:
  • Switch off the pump.
  • Check the gasket condition of foot valve in pump suction line.
  • Check the lubrication of mechanical seal and coupling if required lubricate the same with recommended lubricating grease.
  • Check the condition of coupling between pump and motor, if found damage replaces the same.
  • Check the pump for any abnormal sound if found, check the bearing impeller and other moving parts, if found damage rectifies the same.
  • Checking shall be done on quarterly basis.
• Checking of air blower.
  • Switch OFF the air blower.
  • Check the belt tension, on weekly basis; too tight belts would cause premature bearing failure while too loose belts would cause overheating of belts and pulleys.
  • Check for any knocking and abnormal sounds; high frequency sound indicates bearing problem. Knocking sound indicates rotor timing upset. Contact the technical personnel from the supplier for the proper maintenance.
  • Check the grease / oil levels in the gears and in the bearing end.
  • Oil changed should be done monthly.
  • Checking shall be done on quarterly basis.
• Check the piping and pipe fittings
  • Physically check the piping and pipe fittings for any leakages, if required attend the same.
  • The frequency is as needed; however it shall be check for every month.
• Checking of ball valve, butterfly valve and multiport valve
  • Physically check for smooth movement of valve stem, if found hard then, carry out the valve maintenance as follows:
  • Switch OFF the pump.
  • Close the nearby upward and downward valve.
  • Dismantle the both side flanges of the valve for which maintenance is to be carry.
  • Physically check the valve seat, clean the internals, and re-fix the valve in line, if it is not functioning well then replace the same.
  • The valve checking frequency is on monthly.

• Checking of flash mixer agitator
  • Check the flash mixer agitator RPM with the help of tachometer.
  • Clean the scaling on agitator blade.
  • Check the agitator nut and bolts; if required tighten the same.
  • The frequency is on monthly basis.
• Checking of primary and secondary tube settler
  • Check the strength of structure for tubes by visual inspection, as the level for all tubes is equal if any disturbance in arrangement is appear then check the support structure for strength if required rectify the same.
  • Clean the tubes of tube settler. The frequency is on quarterly basis.
  • Physically check the operation of sludge withdrawal valve. The frequency is as needed.
  • Clean the baffles at effluent weirs as on needed.
  • Clean the sludge collector of tube settler. The cleaning frequency is on half yearly.
• Checking of Aeration tank (MBBR Reactor)
  • Physically check the air diffusers for uniformly flow, if required clean the same .Frequency is as needed.
  • Physically check the air diffuser pipe is found damaged, then rectify the same. Frequency is as needed.
  • Physically check the SAFF media for any damaged; if required replace the same.
  • Physically check and clean the weirs at inlet and outlet of aerator. The frequency is on weekly.
  • Physically check and clean the fills, check the fill support structure for strength. The frequency is on semi annually.
  • Check the aerator blowers for the current withdrawal and voltage rating.
  • Frequency is on half yearly.
• Checking of PSF
  • Physically check the support structure of PSF.
  • Physically check for the structure of PSF pressure vessel for any dent; damage and leakage if required rectify the same.
  • Change the media of PSF annually.
  • Clean the vessels internally by water thoroughly.
  • Physically check the condition of rubber lining of the PSF pressure vessel.
  • Fill the new filter media in PSF. Before filling it close the bottom strainer and flange.  And refill the sand from top end.

• Checking of ACF
  • Physically check the support structure of ACF.
  • Physically check for the structure of ACF pressure vessel for any dent; damage and leakage if required rectify the same.
  • Change the media of ACF by annually.
  • Clean the vessels internally by water thoroughly.
  • Physically check the condition of rubber lining of the ACF pressure vessel.
  • Fill the new filter media in ACF. Before filling it close the bottom strainer and flange.  And refill the sand from top end.
• Checking of feed water storage tank
  • Physically checks the any leakage from the storage tank, if required rectify the same.
  • Physically checks for any dent, damage; if required rectify the same.
  • Physically check the corrosion spot, if required pain the tank with anticorrosive paint.
  • The checking frequency shall be after every six month.
• Preventive maintenance of Effluent Treatment Plant of Electrical
• Checking of Electrical Panel
  • Ensure that the main power supply to the Electrical Panel is switched off.
  • Visually check all the power and control wiring and terminals in the electric panel and at all the field instruments for any sign of overheating and loose terminals.
  • Remove dust from control panel with help of air blower.
  • Physically check and ensure by using appropriate tools that all the wires are properly tightened.
  • Physically check and ensure that double earthing is provided to the panel.
  • Ensure that there is no chance for the entry of dust into the panel.
  • Check and ensure that all switches are working.
  • Check the condition of rubber mat.
  • Check and ensure that the all indicators are working properly.
  • Check the working of voltmeter.
  • Check the working of ampere meters.
  • Check the conditions of display signs for each switches and indicators.
  • Check the working conditions of exhaust fans.
  • Check the working conditions of thermocouple for the exhaust fan working.
  • Checking shall be done on quarterly basis.
• Checking of motor
  • Switch off the main power supply to panel before starting the preventive maintenance.
  • Check the physical condition of base frame; and tightness of nut and bolts; if required tight the same.
  • Check the insulation resistance of motor winding with the help of meagger.
  • Check the phase continuity and winding continuity of motor with the help of tong tester.
  • Physically check the motor terminal box, gland and terminal connections.
  • Check the voltage and current drawn by motor with the help of multimeter
  • Physically check the direction of rotation; it should be as per recommended direction.
  • Checking shall be done after every six month.
• Checking of Contactors
  • Ensure that the power supply to the machine is switched off.
  • Open contactor contact points cover.
  • Physically check all the contacts for pitting and carbon deposits in the contacts.
  • Clean all the contacts with carbon tetra chloride or with contactor cleaner.
  • Clean the electrical control panel with the help of air blower or vacuum cleaner.
  • Replace the contacts if found damaged or welded.
  • Check the earthing of the panel body.
  • A good earthing shall show less than 2 Volts between the Neutral Wire of the Incoming Power supply and Panel Body.
  • Checking of contactors shall be done on monthly basis.
• Post Preventive maintenance of Effluent Treatment Plant – Check List
  • Record the preventive maintenance details as per the Format No.: SOP/EN/XXXYYY“Preventive Maintenance Checklist & Record for Effluent Treatment Plant”.
  • Whenever any modifications and major works are carried out to the equipment, the same shall be mentioned in the equipment history card as per the respective SOP.
  • Connect the equipment main power supply and start the equipment.
  • Ensure that the equipment is running smoothly, without any abnormality.
  • If any abnormality is observed in the above, same will be attended in co-ordination with User department Head.
• ABBREVIATIONS:
  • CRF No.           :         Change Request Form number
  • ETP                  :         Effluent Treatment Plant
  • RPM                 :         Rotation Per Minute                                                                                     
  • MSRL               :         Mild Steel with Rubber Lining
  • QA                    :         Quality Assurance
  •  PSF                   :         Pressurized Sand Filter                                                                                    
  • ACF                  :         Activated Carbon Filter                                                                                 
  • MBBR              :         Moving Bed Biofilm Reactor
• REFERENCES:
  • Execution of preventive maintenance of Effluent Treatment Plant  : SOP/EN/XXXYYY 
• DISTRIBUTION LIST:
  • SOP shall be distributed to following departments Quality Assurance, Engineering as per user request.
• ANNEXURES:
  • Preventive Maintenance Checklist & Record for Effluent Treatment Plant: SOP/EN/XXXYYY

Preventive maintenance of Effluent Treatment Plant Checklist and Records

You may also read about Good Laboratory Practices (GLP)