OPERATION AND MAINTENANCE OF DM PLANT

OPERATION AND MAINTENANCE OF DM PLANT

1.0 OBJECTIVE : Objective of this procedure is to provide operation and maintenance instruction of Dematerialization Plant  (DM Plant) as per safety and cGMP requirements.

2.0 SCOPE: This SOP covers the instructions for operation & maintenance of DM Plant. The SOP also covers preventive maintenance schedule and gives guideline for maintaining critical spares generally required for maintenance. The SOP specifies the responsibilities of staff for the various functions outlined here under.

3.0 SYSTEM REQUIREMENT: A number of minerals readily dissolve into raw water. DM Plant  removes mineral salt by an ion-exchange process from the raw water. After demineralization water passes through the fine filtration and UV sterilizer so that the water meet all the specification of pharmaceutical for purified water

4.0 SYSTEM DESCRIPTION:

The Indion Packaged Up flow DM Plant consists of water feed pumps (one working one stand by) with motor, activated carbon filter, strong acidic Cation unit, strong alkaline anion unit, Mixed bed unit, 5 micron filter, UV sterilizer, inter connected pipe work with valves & ejectors, pressure gauges, flow meter, conductivity meter etc.,

In Activated carbon filter (ACF), Activated carbon used is in granular form which is filled in mild steel pressure vessel. ACF eliminates suspended solids and absorbs most pollutants dissolve in water like detergents, phenols, obnoxious gases like chlorine & sulphur dioxide. It also helps to reduce the impurities like colour, taste etc.

Cation Exchange column of MSRL material contains strongly acidic Cation Exchanger resin. The Cation Exchange material, which exchanges Cations such as Calcium, Magnesium and Sodium for hydrogen ions to form the corresponding acids. This process is reversed when the resin is regenerated by hydrochloric acid through column.

Anion Exchange column of MSRL material contains a strongly basic Anion resin.  The strongly basic Anion Exchanger will remove the acid formed by the cation exchange material and producing water, which is free from dissolved solids. This process is reversed when the resin is regenerated by Caustic Soda solution Mix bed Exchange column of MSRL material contains Cation and Anion resins and thoroughly mixed with compressed air.  When the water passes through Mixed Bed Column the traces of dissolved salt leaked out will be retained in the Mixed Bed Column.

Conductivity meter is used to show the purity of dematerialized water. The conductivity is proportional to be the residual ionized solids in the water. Low conductivity indicates water of high purity.

5 micron filters with SS housing removes the particular impurities from the water.

UV as disinfections is used for removing microbial reduction.

The unit is fitted with all necessary piping, valves & ejectors from the raw water inlet and to DM water outlet.

5.0 OPERATING PROCEDURE:

• Ensure prior to start up -  First time after every maintenance:

Ø      Ensure that Activated carbon filter, Cation, Anion, Mix bed,  vessel is filled with specified and required quantity resin.

Ø      Ensure that the all valves are in operation.

Ø      Check that all piping work is carried as per its piping drawing given in manufacturer’s manual.

Ø      Ensure that there is no water leakage.

Ø      Ensure that the DM plant feed water pump gives rated flow and pressure required for DM plant.

Ø      Test the water inlet quality. It should be as per specification given in design data.

Ø      Ensure raw water pressure at the inlet is not less than 1.7 to 2 kg/cm2

·         Starting Procedure / Instruction of DM Plant

Ø      Open the GIDC raw water inlet valve leading to the suction line of the DM plant feed water pump.

Ø      Switch ON the DM plant feed water pump.

Ø      Slowly open the pump discharge valve leading to the inlet valve of the DM plant.

Ø      Open the Cation inlet valve V1.

Ø      Open the Anion inlet valve V5 and rinse outlet valve V7

Ø      Adjust V7 to get specified rinse flow to drain.

Ø      Open valve V12 to allow some flow through the conductivity cell.

Ø      Switch ON the conductivity meter to ‘CALIBRATE’

Ø      If the needle on meter indicates exactly 40, move to ‘READ’ position

·         Stopping Procedure / Instruction of DM Plant

Ø      Switch OFF the conductivity meter.

Ø      Switch OFF the DM water feed pump.

Ø      Close the Anion outlet valve V6.

Ø      Close the Anion inlet valve V5.

Ø      Close the Cation inlet valve V1.

Ø      Close the GIDC inlet raw water valve.

·        Acid Injection:

Ø     Prepare the stipulated quantity of acid + dematerialized water solution by stirring in the measuring tank.

Ø      Open the main raw  water inlet valve V1, acid ejector power water valve V3.

Ø      Open the acid outlet valve V10.

Ø      Open the acid ejector suction valve V4.

Ø      Adjust V3 to maintain the specified flow to drain, such that the acid measuring tank is emptied in the specified time, leaving only a dead level of 25 mm in the tank.

Ø      Now close valve V4.

·        Acid Rinse:

Ø      Adjust valve V3 to maintain specified flow for the specified time.

Ø      At the end of this specified period, it is advisable to take a sample from valve V10 and test it for pH with the help of pH strip.

Ø      If the result of the test is satisfactory, close valves V10 and V3.

·        Soda Injection:

Ø     Prepare the stipulated quantity of caustic soda + dematerialized water solution by stirring in the measuring tank.

Ø      Open the main raw water inlet valve V1, caustic ejector power water valve V8.

Ø      Open the caustic outlet valve V11.

Ø      Open the caustic ejector suction valve V4.

Ø      Adjust V8 to maintain the specified flow to drain, such that the acid measuring tank is emptied in the specified time, leaving only a dead level of 25 mm in the tank.

Ø      Now close valve V9.

• Soda Rinse:

Ø      Adjust valve V3 to maintain specified flow for the specified time of 30 min..

Ø      At the end of this specified period, close valves V8 and V11.

• Final Rinse:

Ø      Open valve Anion inlet valve V5 and final rinse outlet valve V7.

Ø      After @ 20 minutes, open conductivity cell isolation valve V12

Ø      Switch ON the conductivity tester. Reading must be below 30 uS/cm.

Ø      Close final rinse outlet valve V7.

Ø      Open Anion outlet valve V6 to send DM water to service.

After 30 to 40 minutes we can get an acceptable level of conductivity

·        Ensure prior to start up of Mixed Bed Unit – Only first time:

Ø      Ensure that mixed bed vessel is filled with specified and required quantity resin.

Ø      Ensure that the all valves are in operation.

Ø      Check that all piping work is carried as per its piping drawing given in manufacturer’s manual.

Ø      Ensure that there is no water leakage.

Ø      Ensure the specified flow rate.

Ø      Test the water inlet quality. It should be as per specification given in design data.

·               Preparation of Regenerants:

Ø     Prepare the 6L Hydrochloric Acid + 30L dematerialized water solution (10%) by stirring in the measuring tank.

Ø     Prepare the 2.6 kgs Caustic + dematerialized water solution (10%) by stirring in the measuring tank.