Overview of Iron and Manganese Removal Devices 　　The rocks and soils in the earth's crust are eroded by carbonic acid, causing organic matter to dissolve iron and trivalent iron oxides to be reduced under anaerobic conditions, resulting in a large amount of iron entering groundwater, especially in areas with high iron content such as river floodplains. For example, the iron content of groundwater in the Pearl River Delta, Yangtze River Delta, river banks and coastal areas is generally 10-15 times higher than the domestic water standard. The iron and manganese removal device uses oxidation methods to oxidize low valent iron ions and low valent manganese ions in water into high valent iron ions and high valent manganese ions, which are then removed through adsorption filtration to achieve the goal of reducing the iron and manganese content in water. The filter material is made of refined quartz sand or manganese sand. Process method for removing iron and manganese At present, there are two methods for removing iron and manganese from groundwater: natural oxidation method and contact catalysis method. The CT type pressure type groundwater iron removal device adopts the internationally advanced contact catalytic iron and manganese removal process. The treatment process forms r-type iron oxide hydroxide (r-FOOH) and utilizes the catalytic effect of r-FeOOH to remove iron from the water through processes such as contact, adsorption, catalysis, oxidation, and separation. The main reactions are as follows:

　　Fe2+＋FeO(OH)→FeO(OFe)+＋H+

　　FeO(OFe)+ ＋O2＋H2O→FeO(OH) ＋H+

　　Contact catalytic removal of iron and manganese uses quartz sand or natural sand as filter media, while contact catalytic removal of manganese mainly relies on natural manganese sand filter media.

Heideneng 4040 reverse osmosis membrane	Dow 8040 reverse osmosis membrane

Scope of Application

　　Pressure type iron (manganese) removal device is generally suitable for general underground iron and manganese removal.
　　·PH>6, ρ (Fe)<10mg/l, using single-stage equipment.
　　·PH>6, ρ (Fe)=10-20mg/l, using two-stage series connection.
　　·PH>6.5, ρ (Fe)<2mg/l, ρ (Mn)<1.0mg/l, single-stage iron and manganese removal can be used.
　　·PH=5.5~6.0, ρ (Fe)<5mg/l, single-stage treatment can still be used, but water quality stability treatment should be carried out.
　　·When pH<5.5 or ρ (Fe)>20mg/l, or when both iron and manganese contents are high, the process flow should be determined through experiments if necessary based on the water quality.