Commissioning is an indispensible part of seawater desalination RO system, in order to work out reasonable operation method and operation parameters, and ensure the normal parameters of whole system, including qualified production quality, system protection and comprehensive assessment of system design and equipment situation, etc. This paper mainly describes how to do commissioning of seawater desalination RO system, and do’s and dont’s in the commissioning process.
13 manual operation steps of Seawater Desalination RO System:
1, Use the pretreatment production to flush the security filter before RO unit, confirm the filter is clean and equipped with filter element.
2, Use the production of security filter to flush each pressure vessel and pipe of the RO device, and then clean the inner of pressure vessel by detergent, and finally flush with fresh water.
3, Arrange RO membranes according to the running water flow direction, and one by one installed into the pressure vessel ( use pure glycerol lubrication in the installation process, so as not to damage the sealing ring)
4, Record each membrane module number according to the installation sequence.
5, Close inlet and outlet of pressure vessel, and reset the device to be used.
6, Under the state of pretreatment device into operation, open RO device concentrated discharge valve, concentrated control valve, production discharge valve, inlet valve, and the outlet control valve of the high pressure pump, and then low pressure flush reverse osmosis device. After concentrated discharge foam decreases significantly, stop pretreatment and close RO inlet valve, concentrated discharge valve, concentrated adjusting valve and production discharge valve, making RO membrane soaked in one night and full contacted with water to avoid affecting membrane performance in the process of commissioning.
7, Open slightly high pressure pump outlet control valve, and semi open concentrated control valve.
8, close concentrated discharge valve and inlet valve, and open high pressure pump 10 seconds later, meanwhile open antiscalant metering pump.
9, open the RO device inlet valve ( full opening time in 15 seconds), slowly adjust high pressure pump outlet control valve, so that the RO inlet pressure gradually increases, and thus not exceed 1.0MPa in the beginning.
10, Check whether there is leakage with RO device and pipelines, and whether instrument valve is normal or not. If normal it can slowly adjust concentrated control valve, making production recovery rate gradually rising. In the beginning it is not suitable to control the production recovery rate with 75%, but control within 60-70% at first and then rising to 75% slowly.
11, Record all operating parameters of RO device after normal operation. Remark antiscalant metering pump and related metering pumps again, and check whether the dosage is in accordance with the design requirements.
12, Detect the production conductivity. If conductivity meets the design requirement, first open production outlet valve, and then close production discharge valve.
13, Use RO production to flush middle water tank.
Do’s and dont’s in the process of commissioning:
- In the commissioning process inlet pressure should not be greater than
- 15MPa, and only limited to the pressure test for device.
2, If inlet temperature is higher than or below to 25?, it should be revised based on the curve of water temperature-production, controlling recovery rate is 75%. - After 4 hours of continuous operation, if the desalination rate could not reach the designed rate, each device should be checked one by one, and confirm the broken-down devices should be replaced.
- If there is leakage with high pressure pipes, the device should discharge the pressure. It is strictly prohibited to loosen high pressure fitting under high pressure situation.