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The SOP for the operation of the Effluent Treatment Plant (ETP) and Sewage Treatment Plant (STP) to define the comprehensive procedure for handling the waste of pharmaceuticals. Effluent Treatment Plant (ETP) – The mechanism or process used to treat the wastewater prior to release into the environment or its reuse. Sewage Treatment Plant (STP) -It is the process of removing contaminants from wastewater and household / industrial sewage, both runoffs (effluents)

SOP : Effluent Treatment Plant (ETP) & Sewage Treatment Plant (STP) / SOP for ETP and STP

Purpose:

• To lay down a procedure for the operation of Effluent Treatment Plant (ETP) & Sewage Treatment Plant (STP)

Scope:

• This procedure applicable for operation of Effluent Treatment Plant (ETP) and Sewage Treatment Plant (STP).

References & Annexures:

• References: In-house
• Annexures:
  • Daily ETP Performance & Operation Record
  • Daily STP Performance & Operation Record
  • Monthly ETP Performance Record.
  • Monthly STP Performance Record.

Responsibilities:

• User Department / Area in-charge of ETP/STP:

  • Ensure the operation done as per SOP for ETP and STP.
  • Ensure effective control measures implemented and sustained.

•     Head Environment Health and Safety (EHS):

  • Provide training to all relevant Staff regarding the Operation activity & related documentation of SOP for ETP and STP.
  • To co-ordinate with relevant staff and support for the smooth operation as per SOP for ETP and STP.

•    Quality Assurance Department:

  • Check the SOP and maintain the master copy of SOP for all departments.
  • Issue controlled copy of SOP & maintain issuance copy record.
  • Retrieve the control copy of superseded SOP  .
  • Monitor the review process of the SOP.
  • Ensure implementation of SOP.

Distribution:

•    Environment, Health & Safety (EHS)
•    Quality Assurance (QA)
•    Information Technology (IT)

Abbreviations and Definition of Terms:

• Abbreviations :

  • SOP        :   Standard Operating Procedure
  • ETP       :    Effluent Treatment Plant
  • STP       :   Sewage Treatment Plant
  • EHS      :   Environment Health Safety
  • PPE       :   Personal Protective Equipment
  • DAP     :   Di-ammonium Phosphate
  • SAFF    :   Submerged Aerobic Fixed Film
  • PSF        :   Pressure Sand Filter
  • ACF      :    Activated Carbon Filter   
  • KL         :   Kilo Liter
  • PPM               :   Parts Pre Million

• Definition of Terms:

  • Waste Water: Used water after for domestic or industrial purposes.
  • Effluent: Treated wastewater, flowing from a tank, treatment process, or treatment plant.
  • Effluent Treatment Plant (ETP):
    • The mechanism or process used to treat the waste water prior to release in to environment or its re- use.
  • Sewage Treatment Plant (STP):
    • It is the process of removing contaminants from waste water and house hold / industrial sewage, both runoffs (effluents).
  • Settling Tank:
    • A vessel / tank in which solids settle out of water by gravity during wastewater treatment processes.
  • Sludge:
    • Any solid, semisolid, or liquid waste that settles to the bottom of settling tanks (in Effluent Treatment Plants or Sewage Treatment Plants) or septic tanks.

 Procedure (SOP for ETP and STP):

• Operation of Effluent Treatment Plant (ETP) & Sewage Treatment Plant (STP)

  • Shall carried out by the operators / Technician’s in each shift round the clock under the supervision of the area in-charge and above.
  • Before operation any pump care should taken
    • That any valve properly placed or not .

• Operation of Effluent Treatment Plant – SOP for ETP and STP :

  • Effluent comes from the plant in to Effluent collection sump (T – 17) having capacity 50 KL.
  • Two Nos. Pump (P – 08 A / B) provided with level sensor for automatic control of effluent level in collection sump to avoid over flow and then effluent comes into bar screen chamber of Inlet chamber (T – 01)
  • Then effluent enters in to inlet Chamber having capacity 2.5 KL and again over flows to Oil Grease Tank (T – 02 ) having capacity 9 KL
  • The oil obtained as a floating scum at the surface of the oil and grease tank and this is skimmed off manually in to the oil collection drum.

• • Then the over flow of oil free effluent enters in to Equalization Tank (T – 03 A / B) having capacity each 45 KL and ensure that only one valve open at a time. i.e. raw effluent enters in to either in to tank T – 03 A or T – 03 B.

• • Equalization tank (T – 03 A / B) is provided by diffused air grid system comprising of air blowers (AR – 01 A / B) to avoid any shock load and equalize both hydraulic or organic load to the system.

• Safety measures and Testing ( SOP for ETP and STP) :

  • Prepare dosing solutions as per instruction provided by the area in-charge.
  • Use proper PPE’s like Nose, Mask, Gumboot, Hand gloves, Safety goggles etc. while handling chemicals.
  • Also follow safety instructions provided by handling chemicals from MSDS / SDS.
  • Performing jar test for raw effluent when chemical or effluent quality changes fix the dosing rate.

  • Lime Dosing Solution – (SOP for ETP and STP)

    • Do the Lime dosing in HDPE tank (T – 13) having capacity 500 Liters with Concentration 10 % .
    • Prepare the solution preparation with portable water supplied by the designated area before run the operation activity.
    • Switch on the agitator for proper mixing of the chemical & tank cleaning activity should perform as when required.

  • Alum Dosing Solution – (SOP for ETP and STP)

    • Alum dosing done in HDPE tank (T – 14) having capacity 500 Liters with Concentration 10 % .
    • Solution preparation done with portable water supplied by the designated area before run the operation activity.
    • Switch on the agitator for proper mixing of the chemical & tank cleaning activity should perform ( when required).

  • Polyelectrolyte Dosing Solution – (SOP for ETP and STP)

    • Polyelectrolyte dosing done in HDPE tank (T – 15) having capacity 250 Liters with Concentration 0.1 to 0.2 % .
    • Solution preparation done with portable water supplied by the designated area before run the operation activity.
    • Switch on the agitator for proper mixing of the chemical & tank cleaning activity should be performed as when required.
    • After dosing lime & Alum in Equalization flocks are observed,
    • After sample check effluent transferred to PST (primary settling tank) (T – 04) having capacity 7.9 KL.
    • Inlet Effluent is measured to an inlet flow meter and documented as per Annexure – 1 in each shift.
    • Effluent transfer performed from Equalization to PST by 4 Nos. effluent transfer pump (P – 01 A / B / C / D)
    • where one running at a time others standby & flow rate fix by adjusting the recirculation line of these pumps.

                      Tube settler is fixed in Primary settling tank (PST) which are inclined PVC media for                                 better settlement polyelectrolyte solution dosed in the 1^st compartment of PST and care                           should take for the adjust effluent flow rate for better settling conditions avoiding eddy                           currents and turbulence.

• • • Settled flocs in the primary settling tank are nothing but sludge drained off to sludge collection sump (T – 13) on a regular interval (every 24 hours).
    • Primary Settling Tank effluent overflows by gravity to SAFF Reactor Tank – I (T – 05 A) having capacity 60 KL.
    • Oxygen is supplied the SAFF – I & also SAFF – II for aerobic biological treatment by running of Air Blowers (AR – 01 A / B) and arrangement of diffused aeration system to the uniform distribution of oxygen to this tank.
    • Effluent overflows from SAFF – I launder to Secondary Settling Tank – I (T – 06A) having capacity 9 KL.
    • The settled biomass on Secondary Settling Tank – I is recirculated by means of two nos. pumps ( Sludge recirculation pump P – 02 A / B) & excess sludge will be wasted to the Sludge Collection Sump T – 11 as when required or instruction provided by the area in-charge.
    • Secondary Settling Tank – I overflow to SAFF Reactor Tank – II (T – 06 B) having capacity 60 KL.
    • Secondary Settling Tank – II (T – 06 B) having capacity 60 KL. & the settled biomass recirculate by means of two nos. pumps (Sludge re-circulation pump P – 03 A / B) & excess sludge will be wasted to the Sludge Collection Sump T – 11 as when required or instruction provided by the area in-charge.
    • Nutrients like Urea, DAP (Di Ammonium Phosphate) and Jaggery (Molasses Solid form) added to SAFF – I & SAFF – II for proper growth of the biomass as instruction provided by the area in-charge.
    • Launder cleaning done as when required.
    • Secondary Settling Tank – II overflows to Intermediate Collection Tank (T – 07 ) having capacity 11 KL.

  • Hypo-chloride Dosing Solution: 

    • With Concentration 1 ppm, Do the  Hypo-chloride dosing in HDPE tank (T – 16) having capacity 100 Liters.
    • Prepare the solution with portable water supplied by the designated area
      • Hypochlorite solution dosing on the MS baffled inlet launder before running the operation activity.
    • The air grid system provided for proper mixing of hypochlorite to the effluent & tank cleaning activity should perform as when required.
    • From this intermediate collection tank, the mixed effluent will pump into Pressure Sand Filter (PSF) using pump P– 04 A / B having capacity 5 m³ / hr. The retention time of the tank is 2.7 hr.
    • Pressure Sand Filter (PSF) (T – 08) removes the suspended particulate matter, proper backwashing required at the pressure loss of 0.8 kg / cm² observed in the inlet and outlet pressure gauge.
    • The raw effluent line is provided to pump suction line P– 04 A / B & Backwash duration will be 15 to 20 min. for both Filters PSF & ACF, .
    • The backwash effluent of this system taken into the inlet chamber of ETP for retreatment.
    • Before completion of backwash,
    • Ensure that coming to the inlet chamber should clear.
    • Before and after the backwash related valve should check properly. 
    • Treated effluent from Pressure Sand Filter (PSF) then goes to Activated Carbon Filter (ACF) (T – 09) which removes odor and color present in the effluent.
    • Proper backwashing required at the pressure loss of 0.8 kg / cm² observed in the inlet and outlet pressure gauge.
    • After completion of filtration (PSF & ACF), effluent enters into final collection tank (T – 10) having capacity 50.6 KL and finally discharges through two number of the submersible pump ( P – 07 A / B)

• Operation of Filter Press ( FP – 01) – SOP for ETP and STP

  • Before plan to operate filter press equipment check the cleaning status i.e. – with a clean cloth and fixed properly.
  • Filter press operation should start when sludge collection sump (T – 11) having capacity 9.6 KL at least 75 % full and the batch should be made with adding polyelectrolyte.
  • Depends upon sludge characteristic polyelectrolyte dosing quantity should fix by performing jar test or instruction provided by the in-charge.
  • Before feeding sludge in to filter press (FP – 01) line should flush by the portable water line connected to the pump.
  • After completion of the line flushing portable water valve should shut down and the sludge feed valve should open.
  • At the starting of sludge feeding to FP – 01 recirculation valve should adjust.
  • Never shut down the recirculation valve.
  • Initially pressure not shown to the pressure gauge and after some time pressure generated and
  • it should maintain between 2.0 – 4.0 kg / cm²  
  • The operator should ensure the pressure when goes to raise more, recirculation valve should adjust and
  • Backpressure increases due to the generation of sludge cake.
  • Remember overpressure may damage the system.
  • Ensure the filtrate continues through discharge cock/tap and indicates sufficient soluble discharges,
  • when no effluent discharges stop the filter pressure operation.
  • Shut down the second feed valve and open the recirculation valve and flush the running pump. After that stop the pump and plan to give compressed air from the compressor to filter press for removing the effluents/filtrates from the sludge cake.

• When Compressor is breakdown condition (SOP for ETP and STP)

  • Then compressed air should be provided from the plant main compressor line and the operator inform the utility in-charge / area in-charge.
  • Before cleaning the sludge cake ensure the airline valve shut down and mobile trolley placed on proper place and used proper PPE’s.
  • Operate the lever of the hydraulic system reverse direction and switch off from the main panel to avoid any major accident and after completion of the job again switch on from the main panel.
  • Hydraulic system to operate safely when pressure gauge shows 200 – 230 kg / cm²
  • Pull the slide head of the moving plates and remove the sludge cake from sliding one by one plate & sludge cake fall down to the below mobile trolley.
  • Finally cleaned the filter press and removed sludge to pack in a bag and shifted to the hazardous waste storage area.
  • Handling of ETP sludge should perform with PPE’s.
  • Then follow the above relevant steps, then the equipment is ready for the next batch operation.
  • Cleaning of discharge cock/tap and foot valve/check valve to perform (when required).
  • Overall operation time for a batch depends upon the concentration of the effluent sludge and high concentrations of filter press feed sludge reduce the batch completion time.  

• Operation of Sewage Treatment Plant (STP) (SOP for ETP and STP) :

  • Raw effluent comes by gravity to STP inlet chamber A / B (both compartment).
  • Do Screening with a bar screen chamber to separate heavy and grit particles from not entering our system.
  • Effluents then enter into equalization tank A / B (both compartment) to the lower cut out, where oil and grease separate and cleaned manually as when required. Chemical dosing is done in an equalization tank for primary treatment.

  • Caustic soda Dosing Solution :

    • Caustic Soda dosing is done in the HDPE tank having capacity 100 Liters with Concentration 10 %.
    • Solution preparation is done with portable water supplied by the designated area before running the operation activity.
    • Manually mixing of the chemical to be done & tank cleaning activity should be performed (when required).

  • Alum Dosing Solution :

    • Do the Alum dosing with Concentration 10 %  in HDPE tank having capacity 100 Liters.
    • Prepare the solution preparation with portable water. Supplied by the designated area.
    • Manually mixing of the chemical to be done & tank cleaning activity should perform.

• Poly Dosing Solution (SOP for ETP and STP):

  • Poly dosing is done in HDPE tank
    • Having capacity 100 Liters with Concentration of 0.1 to 0.2 %.
  • Solution preparation is done with portable water supplied by the designated area before running the operation activity.
  • Manually mixing of the chemical to be done & tank cleaning activity should be performed as when required.
  • The effluent then enters into the lower cut-out to aeration tank A / B ( both compartment) and
  • Dosed nutrients like Urea, DAP And Jaggery / Molasses (solid form) to maintain the biomass of the system.
  • Aeration tank effluent overflows into the Clarifier tank by gravity on settling and recirculate the return biomass by means of two Nos. sludge recirculation pump A / B.
  • Excess sludge to waste into sludge drying bed / Sludge Collection Sump ( T – 11).
  • Clarifier overflows through launders to Chlorine contact tank and hypochlorite is dosed into this tank.

• Hypochlorite Dosing Solution:

  • Dosing of  Hypochlorite in HDPE tank, Tank capacity should 100 Liters with Concentration 1 to 2 ppm.
  • Solution preparation is done with portable water supplied by the designated area before running the operation activity.
  • Manually mixing of the chemical to be done & tank cleaning activity should be performed as when required.
  • Then effluent overflows into Final treated tank or effluent transferred from chlorine contact tank to final treated tank by means of to nos. pumps A / B
  • Final treated effluent discharges for reuse purposes (gardening/toilet flushing) by means of two nos. of pumps (FTD – 01 A / B)
  • Final treated effluent transferred quantity should be measured by two no’s flow meter F.M – 01 & F.M – 02 in each shift & documented as per Annexure (2)
  • Monthly ETP performance report is prepared by the ETP / STP in-charge / Area in-charge & documented as per Annexure (3)
  • Monthly STP performance report is prepared by the ETP / STP in-charge / Area in-charge & documented as per Annexure (4)

For Annexure and Formats : Click here –SOP and Formats for ETP / STP