We offer services to Operation and Maintenance of effluent treatment plants (ETP) and Sewage treatment plant (STP). We provide dedicated resources and technical assistance for water and wastewater treatment plants some process as bellow;

PRE STARTUP CHECKS;

SEWAGE LIFTING PUMP:

  1. Flush the entire pipeline and the system before lining into the system.
  2. Ensure that pump rotates freely by hand.
  3. Check for Power supply cable connection for motor.
  4. Ensure the direction of rotation of driver corresponds to the direction of rotation of pump

AIR BLOWER:

  • Flush the entire pipeline before lining into the system.
  • Oil to be filled in the oil-chamber.
  • Grease shall be applied for valves & drive chain properly if required.
  • Check for free rotation.
  • Check for Power supply, Cable connection for Motor and check the direction of rotation also.

FILTER FEED PUMP:

  • Flush the entire pipeline and the pump casing before lining into the system.
  • Oil to be filled in the oil-chamber if applicable.
  • Grease shall be applied for valves if required.
  • Check for free rotation.
  • Check for cable connection for motor and check the direction of rotation also.

MULTIGRADE FILTER:

  • Flush the entire pipeline and the system before lining into the system.
  • Open the valve and backwash the system till clear water is collected. Repeat the process with intermediate time of half an hour to one-hour.
  • Proper Operation should be applied for valves
  • Proper rinsing shall be done before putting the plant into service.
  • Check the inlet water quality and ensure the parameters are as per design.
  • Check for inlet water flow rate.
  • After commissioning check the outlet water quality

STARTUP AND NORMAL OPERATION PROCEDURE.

NORMAL STARTUP:

During normal start-up, the plant has to be operated at 25% capacity. All the respective valves have to be opened for 25% of flow except Air blower. The following activities have to carry out 10 days prior to the date on which the plant is to be operational and the sequence of the operation to be done as follows:

  • Start the transfer pump with controlled flow.
  • Check the pH in the collection tank.
  • Check the waste water quality from collection tank.
  • Check the water flow rate of pumps
  • Fill the aeration tank with 25% of volume.
  • Run the Air blower at full capacity.
  • Fill the aeration tank with fresh water.
  • Add the cow dung/culture (Bio – culture) as per the requirement. Add the nutrients – DAP & Urea as per requirement.
  • Check for the DO level and maintain at 1 – 2 mg/l.
  • Start feeding the combined effluent gradually from 25% to 100% into the Aeration tank in order to avoid the load to the culture bacteria

Effluent starts overflow from Aerator tank to Secondary Settling Tank

  • Start the filter feed pump to flush the filters (i.e., backwashing to remove the dirt and mud particles from the pebbles and Sand/Carbon).
  • Start the sodium hypo chlorite dosing in the inlet line of PSF. The dosage level of the chlorine is 2 to 5 ppm.
  • Check for the clarity of the water and enter in the logbook.
  • Now the plant is ready for regular operation.
  • Ensure that the treated water quality at the outlet of the Clarified Water Tank and Activated Carbon Filter is as per the PCB norms

NORMAL OPERATION:

    1. Gradually increase the flow at an interval by opening the respective valves in the pumps to meet the plant capacity and start the plant for regular operation.
    2. Follow the same procedure as in the Normal start-up.  In addition to that performance has to be monitored during normal operation:
    3. Chemicals to be dosed as per requirement and the dosage to be adjusted as per site conditions.
    4. Backwashing of the MGF, when the pressure drop exceeds 0.5 kg/cm2 from the initial pressure drop.
    5. Dosing chemicals to be monitored for the quantity.
    6. Pressure/Capacity to be monitored for the required quantity.
    7. Solid or Cloggy materials should not be allowed near by the Pump suction

MULTIGRADE FILTER AND ACTIVATED CARBON FILTER

Water from the clarified water sump water is pumped by means of Filter feed pump to Pressure Sand Filter.  Filter operation consists of the following steps.

  1. Service cycleIn the service cycle, water enters the filter through the inlet valve and is distributed through the inlet distribution system which reduces the water velocity to 1.0 m/s.  This avoids direct impinging of water on the bed. The inlet turbidity of the water will be 100 ppm before passing through the filter bed. The water passes through the filter media where the turbidity is reduced to <10.0 ppm. The filtered water is then collected through the bottom collecting system which consists of lateral pipes connected to the common header where the filtered water is collected. From the collection system the water comes out through outlet valve and filtered water is fed to the Activated Carbon Filter. A sample from the outlet line pressure gauge drain valve has to be taken and tested at lab for the presence of turbidity.During this cycle inlet valve is opened and the remaining valves of the filter are kept closed. Pressure Sand Filter to be throttled to maintain the required flow rate of water. On putting the filter to service, air vent valve has to be manually opened and the air present inside the vessel is released. Once the water starts coming out of the air release valve, it is closed. The outlet water is fed to the Activated Carbon. This service operation is continued for 20 hours or once the differential pressure across the bed exceeds 0.5 Kg/cm2, after which the inlet and outlet valves are closed.  A pressure gauge is provided on the Filter feed pump discharge line and another on the outlet for monitoring the pressures
  2. BackwashBackwash of filter is done to remove the clogged matter formed on the top surface of the filter media. During backwash the water enters from bottom of filter and passes through media and picks up the suspended solids present on top surface of the filter bed and is led to the collection pit provided near the system.Before backwashing it should be ensured that enough water is available in the clarified water. The backwash has to be carried out for 15 minutes (or) until the backwash water seems to be clear. The backwash flow rate shall be 7.0 m3/hr. Once backwash is completed backwash inlet and outlet valves are closed.
  3. RinsingRinsing of filter is carried out to remove any traces of impurities that are left out during the backwash cycle and setting of bed. The flow of water is from top to bottomAt the beginning of this cycle the valve shall be kept in rinse position. The rinsing operation has to be done for 5 minutes and the rinse flow rate maintained at 3 m3/hr. After rinsing, above valves are closed and the system is ready for service.

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