(1) Physical method
Physical methods include ① precipitation method or air flotation separation method, ② sand filtration, pre-coating (filter aid) filtration, filter cartridge filtration, fine filtration, etc., ③ activated carbon adsorption method, ④ cooling or heating.
(2) Chemical method
Chemical methods include ① oxidation method: use ozone, air, oxygen, chlorine and other oxidants for oxidation, ② reduction method, ③ pH value adjustment method
(3) Photochemical method
The photochemical pretreatment method mainly refers to ultraviolet irradiation.

Technical specifications of drinking water RO system:

Model	JFRO-500L
Host Size	800x600x1600mm (can be customized)
Power	1.5KW
Power Supply	220V /380V/460V - 50Hz/60Hz,220V 50Hz can be customized
Operating Pressure	0.8-1.2MPa
Recovery Rate	50%
Designed Water Inlet	1000L/h
Outlet Flow	500L/h
Desalination Rate	≥99.5%
RO Frame	SUS304
Membrane Size	4040
Membrane Elements	DOW /Hydranautics/Troy/ Vontron (Optional)
Number of Membranes	2
Raw Water Pump	CNP/NYP/GRUNDFOS (Optional)
Raw Water Pump	CNP/NYP/GRUNDFOS (Optional)
Tank Material	SS/FRP (Optional)
Control Valve	Manual/Automatic
Control Valve Brand	FLECK/RUNXIN
Membrane Housing	SS/FRP (Optional)
Pipe Material	U-PVC, Stainless steel (Optional)

Dringking water RO system preprocessing requirements:

1. The reverse osmosis pretreatment must be able to remove most of the impurities in the raw water to meet the water inlet requirements;
2. Reverse osmosis pretreatment must consider changes in water quality to prevent fluctuations in raw water quality from affecting the stable operation of the entire system;
3. The reverse osmosis pretreatment process must be able to operate efficiently and stably, while simplifying the process as much as possible to reduce investment and operating costs

Drinking water RO system process flow:

Source water tank → source water booster pump → multi-media filter → active carbon filter → resin softening device → precision filter → first RO reverse osmosis pure water system → second RO reverse osmosis pure water system → water-gas mixer → ozone sterilizer → stainless steel pure water tank → automatic filling line

Cleaning of drinking water RO system membranes:

A. Cleaning method Dilute the cleaning agent to a certain concentration and pump it into the membrane module for cleaning. In the case of serious pollution, the method of soaking overnight can be used, but the time should not be too long; the contact time between the chemical agent and the membrane should be minimized.
B. Calcium carbonate scale Reduce the pH value of the feed water to between 3.0 and 5.0, and run for 1 to 2 hours.
C. Calcium sulfate scale The best way to remove the scale is to use 7.7kg of sodium tripolyphosphate, 3.18kg of sodium EDTA, and 379kg of reverse osmosis product water, and adjust the pH value to 10.0 with sulfuric acid.
D. Metal oxide scale is removed by the method of removing calcium carbonate scale.
E. Organic sediments can be removed with 7.7kg of sodium tripolyphosphate, 0.97kg of sodium dodecylbenzene sulfonate, 379L of reverse osmosis product water, and the pH value is adjusted to 10.0 with sulfuric acid. If the pollution is serious, this solution can be soaked for 12 hours.