Reverse osmosis membrane unit conversion, temperature, conductivity, installation and removal are so simple

I. Reverse Osmosis Membrane Unit Conversion

1. Unit conversion of size, pore size, diameter, area and water yield of imported reverse osmosis membranes?

Answer: In China's water treatment process, the length unit is generally represented by mm. The scale units of imported equipment need to be converted (in=inch, ft=foot): 1in=25.4mm, 1ft=304.8mm, 12in=1ft;

Reverse osmosis membrane pore size: 10-6in=2.54x10-6mm;

Surface Area: 1ft2=144in² =929x10-4m²=92903mm², 1 in2=6.45 x10-4m²=645.2 mm²;

Flow Rate: UK gpd (gal/d, gallon/day) =4.546L/d=5.26*10-5L/s; US gpd (gal/d, gallon/day) =3.785L/d=4.381*10-5L/s;

Pres sure: 1b/in² (psi, pound-force/square inch) =0.0703kgf/cm², Legal unit: 1pa=1N/m², 1Mpa=106pa,

1psi=6.895kpa=6.895x10-3Mpa; When the reverse osmosis can withstand a pressure of 600psi is 4.14Mpa.

1bar (commonly known as 1 kg) =0.1Mpa; 1mmHg=0.1333kpa;

Free chlorine content < 1ppm, i.e., free chlorine <1mg/L.

2. Temperature conversion? (Thermodynamic temperature, Celsius temperature, Fahrenheit temperature)

Answer: Thermodynamic temperature ( K) = Celsius temperature + 273.15;

℃=5/9（℉-32），℉=9/5℃+32；

Relative humidity can be obtained by dry-bulb thermometer and wet-bulb thermometer; it can also be found in the table.

3. Conductivity correction?

Conductivity correction can be used 0.01mol/L and 0.02mol/L potassium chloride solution for correction, specific method: Place the conductivity electrode to be calibrated in

0.01mol/L or 0.02mol/L potassium chloride solution, maintain the potassium chloride solution at different temperatures with a precision constant temperature water bath, and compare the measured

conductivity with the following table to determine the electrode constant of the unknown constant electrode, and also to verify it.

Conductivity of potassium chloride solution at different concentrations and temperatures ( uS/cm)

II. Component Installation:

1. Remove the end plate and thrust ring from the system pressure vessel.

2. Rinse the opened pressure vessel with clean water to remove dust and sediment.

Note: If further cleaning is required, make a mop large enough to fill the inner diameter of the pressure vessel, let the mop absorb 50% glycerin

aqueous solution, and drag it back and forth in the pressure vessel until the inner wall of the pressure vessel is clean and lubricated.

3. Insert the end of the membrane element without the brine seal ring from the pressure vessel inlet direction, and push the element in about half way.

Note: It is stipulated that the element must be installed from the inlet of the pressure vessel.

4. Confirm that the direction of the brine seal ring on the element stressor is correct. That is, the opening direction of the seal ring should face the inlet direction.

Insert the connecting joint between the elements into the central water outlet pipe of the element. Before installing the joint, you can apply a small amount of glycerin (except for special cases where it is not allowed)

to the O-ring on the joint.

5. Install the second element and connecting joint in turn, carefully hold the element, do not let the connecting joint bear the weight of the element, and push the element

into the pressure vessel until about half of the element is exposed outside.

6. Repeat steps 4 and 5 until all elements are installed in the pressure vessel. The length of the element and pressure vessel determines the number of elements in a single pressure vessel.

7. Install the thrust ring at the concentrate end of the pressure vessel and locate the thrust ring according to the diagram of the pressure vessel manufacturer.

8. Install the end plates at both ends of the pressure vessel according to the following steps:

a) Carefully position the pressure vessel concentrate end plate, align the element and push into the end plate assembly, carefully place the O-ring on the transition joint (adapter) between the element and the end plate, and insert the transition joint into the element to avoid twisting or turning the O-ring.

b) Rotate and adjust the end plate assembly to align with the external connecting pipe.

c) Install the end plate retaining ring according to the diagram of the pressure vessel manufacturer.

d) Push the RO element from the inlet side to the concentrate side.

e) Before installing the inlet end plate, it is recommended to adjust the gap between the element and the end plate with shims. This step can help prevent the element from moving and impacting each other during system startup and shutdown.

f) Install components on each pressure vessel in the system using the same method as steps a) to e).

9. Connect all external pipelines.

III. Disassembly of components:

1. First, remove the external hard pipes from both ends of the pressure vessel. If necessary, refer to the pressure vessel manufacturer's diagram. Label all removed parts and store them in order.

2. Remove the vessel end plate assembly from both ends of the pressure vessel.

3. Push the RO element out of the pressure vessel from the inlet of the component. Push out one element at a time. When the element is pushed out of the pressure vessel, catch it immediately to prevent damage to the element or injury to personnel.