Nanofiltration of high-salt wastewater---Related configurations of reverse osmosis salt separation device
Nanofiltration of high-salt wastewater----Related configurations of reverse osmosis salt separation device
The produced water flow is 77m3/h, the design recovery rate is 70%, the design flux is 16.5LMH, and the sulfate removal rate is ≥95%. The number of membranes required for calculation is 138, and the membrane shell is 6-core, with a total of 23 membrane shells.
Since the influent COD is about 100mg/L, in order to ensure sufficient cross-flow rate on the concentrated water side of the membrane, a three-stage design is adopted, and an inter-stage booster pump is set to balance the inter-stage flux and water production. The membrane shell arrangement ratio is 12:7:4, and the inter-stage booster pump boost pressure is adjusted to 5bar. The calculation results are shown in the figure below. The water inlet of a single membrane shell can be guaranteed to be above 9m3/h.
water quality report
1. Security filter: FRP horizontal membrane shell type, external pressure filtering. Single filter processing capacity 20m3/h, 6 filters are selected, each filter inlet and outlet is equipped with manual butterfly valve to ensure non-stop filter element replacement. 40-inch filter element total length L = 1120mm, end and tail cover diameter Φ154±1mm.
2. Water pump: High-pressure pump Q=110m3/h, H=190m, N=90kW; two-stage booster pump Q=68m3/h, H=50m, N=18.5kW; three-stage booster pump Q=45m3/h, H=50m, N=15kW; water pump material is SS2205
3. Membrane housing: According to the operating pressure of each section, the first, second and third section membrane shells are respectively selected from the 8040 series 300, 450 and 450psi membrane shells. The outer diameter of the membrane shell is φ244mm, and the inner diameter is φ203mm. When designing the device, the first section is at the bottom of the membrane frame and the third section is at the top of the membrane frame. The three sections of concentrated water pipeline are higher than the installation height of the membrane shell at the highest point of the skid frame.
4. Instrumentation: Pressure gauges are installed at the inlet and outlet of the security filter, each section of the water inlet and concentrated water, and the water production pipe; each section of the water inlet and concentrated water, The pressure transmitter is installed at the water production pipe and the concentrated water production pipe; the security filter is installed with a differential pressure transmitter; the inlet and outlet of the high-pressure pump are respectively installed with a low-pressure switch and a high-pressure switch; the water production pipe and the concentrated water pipe are installed with a remote flow meter; the first and second sections of the water production are installed with a rotor flow meter;
5. Frame: The bottom is made of 12# channel steel, the vertical support and the membrane tube horizontal support are made of 8# square tubes, and the rest are made of 5# square tubes.
6. Automatic valve: equipped with pneumatic valve for water production discharge; pneumatic valve for concentrated water discharge; electric valve for water inlet; electric valve for flushing water inlet;