RO reverse osmosis membrane replacement process and program in pure water equipment

RO reverse osmosis membrane replacement process and program in pure water equipment
Part I: Preparation
1.1 Prepare all the tools that may be used in the construction process
1.2 Clean the upstream inlet pipe line;
1.3 Carefully assess the quality of incoming water;
1.4 Check the piping for leaks;
1.5 prepare a water-soluble lubricant (chemically pure glycerine);
1.6 ensuring that all parts and chemicals used are complete;
1.7 checking that the pre-treatment system is functioning and that the water is coming out properly.

The second part: reverse osmosis old membrane dismantling and new membrane installation
2.1 Dismantle the pressure vessel of reverse osmosis membrane, unify all end caps and parts, and store them in order.
2.2 Take out the old reverse osmosis membrane element in the pressure vessel, and flush the pressure vessel clean.
2.3 Take out the new membrane element, check whether the position and direction of the brine seal ring on the element is correct (the opening direction of the brine seal ring must face the direction of water intake).
2.4 Push the end of the membrane element without brine sealing ring from the inlet end of the pressure vessel parallel to the membrane shell until the element is exposed outside the inlet end of the pressure vessel for about 10 centimeters.
2.5 Insert the connecting tube between the elements into the center tube. Before installation, apply a small amount of glycerin lubricant to the “O” ring of the joint, or if not available, wet it directly with qualified pretreatment water.
2.6 Remove the second membrane element, check that the brine seals on the element are in the correct position and orientation, hold the element and allow the connecting tube on the first element to be inserted into the center tube of the element, and push the element into the pressure vessel in parallel until the second element is exposed for approximately 10 centimeters.
2.7 . Repeat until all elements are in the pressure vessel, transfer to the thick water end, install the connecting tube on the first element center tube, the length of the element and the pressure vessel determines the number of membrane elements that can be installed in a single pressure vessel, install the thrust ring on the thick water end of the pressure vessel during installation.
2.8. Check the “O” ring on the element adapter, insert the element adapter into the thick water end plate, align the element connecting tube and push the thick water end plate assembly parallel to the pressure vessel; rotate and adjust the thick water end plate assembly to align it with the external connecting tube; install the end plate snap ring.
2.9 Push the membrane element from the inlet side to the thick water side until the first installed membrane element is in firm contact with the thick water end plate.
2.10 . Install the influent end plate. Before installing the inlet end plate, in order to prevent axial runout of the element and impact between the elements during system start-up and shutdown, adjust the gap between the membrane element and the end plate with an adjustment piece (thickness 5mm).
2.11 Repeat the above steps to install membrane elements in each pressure vessel and connect all external feed, concentrate and production water lines.

Part III: Equipment commissioning
3.1 Pre-commissioning inspection and preparation, which includes the following parts:
1. Configure measuring instruments, calibration of the instruments;
2. Setting up the sampling points of each link of the system, and correctly setting up the interlocking, time delay and alarm devices;
3. Checking the pressure vessel and cleaning line connections and tightening all joints;
4. test run the pumps and other rotating equipment under no load to ensure that the steering is correct and well lubricated;
5. Open the produced water discharge valve, open the thick water discharge valve;
6. Before starting the high-pressure pump, adjust the opening of the high-pressure pump discharge valve to control the membrane system water inlet flow is less than 50% of the operating water inlet.

3.2 Check all valves and ensure that all settings are correct and that the membrane system produced water discharge valve, influent control valve and concentrated water control valve must be fully open.
3.3 . Use low-pressure, low-flow qualified pretreatment effluent to drive out air from within the membrane element and the pressure vessel, and all produced and concentrated water from the process should be discharged water to the sewer.

3.4 . During flushing operations, check all valves and piping connections for leakage points.
3.5 Systems with dry membranes should be flushed continuously at low pressure for more than 6 hours or flushed for 1 to 2 hours, soaked overnight, and then flushed for about 1 hour. Scale inhibitors are not permitted to be applied to the pretreatment section during low-pressure, low-flow flushing.
3.6 . Reconfirm that the produced water valve and the thick water control valve are in the open position.
3.7 The first time the high pressure pump is started the inlet control valve between the high pressure pump and the membrane element must be in a state close to fully closed to prevent the impact of water flow and water pressure on the membrane element.
3.8 Start the high-pressure pump.
3.9 Avoid the membrane system super-flow super-pressure impact, in the high-pressure pump should be slowly opened after the start of the high-pressure pump outlet inlet control valve uniformly increase the concentrated water flow to the design value, the rate of pressure should be less than 0.07 MPa per second .
3.10 . Slowly open the high-pressure pump outlet inlet control valve at the same time, slowly close the thick water control valve to maintain the system design of the thick water discharge flow, while observing the system water production flow, and gradually adjust the recovery rate to the design value.
3.11 Check whether all chemical dosage is consistent with the design value, and determine the pH value of the influent water.3.12 . The system runs continuously for 1 hour. When the produced water is qualified, open the qualified produced water delivery valve and then close the produced water discharge valve to supply water to the subsequent equipment. Record all the operating parameters in the first group. The above adjustments are generally made in manual operation mode and the system is converted to automatic operation mode after stabilization.
3.13 After 24 to 48 hours of continuous operation, review all recorded system performance data, including influent pressure, differential pressure, temperature, flow rate, recovery rate and conductivity. Also sample and analyze the influent, concentrate and total system produced water. Confirm that the equipment is operating properly and construction is complete.