Heavy Metal Wastewater | Heavy Metal Wastewater Treatment Process

　　Regarding heavy metal wastewater, the following mainly discusses the basic concepts of heavy metal wastewater, general regulations of heavy metal wastewater and heavy metal wastewater treatment processes.

　　I. Heavy Metal Wastewater

　　It refers to wastewater discharged from electroplating production that contains metal ions such as cadmium, chromium, lead, nickel, silver, copper, and zinc. According to the heavy metal elements contained in the wastewater, it is also called cadmium-containing wastewater, chromium-containing wastewater, lead-containing wastewater, nickel-containing wastewater, silver-containing wastewater, copper-containing wastewater, zinc-containing wastewater, etc.

　　II. General Regulations for Heavy Metal Wastewater

　　1. When the wastewater contains cyanide, the cyanide should be removed first; if the wastewater contains hexavalent chromium ions, the hexavalent chromium should be reduced to trivalent chromium, and then the heavy metal ions in the wastewater should be treated.

　　2. When treating a certain type of heavy metal wastewater by ion exchange, other types of plating wastewater, floor flushing wastewater, etc. must not be mixed in. The ion mass concentration should not be greater than 200 mg/L. The design, operation control technical conditions and parameters of ion exchange treatment of heavy metal wastewater shall comply with the relevant regulations and requirements in GBJ 136. All the drained water from backwashing and rinsing of filter columns and exchange columns should enter the electroplating wastewater treatment system and be reused or discharged after treated and reaching the standard.

　　3. When reverse osmosis equipment is adopted to treat heavy metal wastewater, pretreatment measures such as sterilization and scaling control should be taken. The concentrated water produced by the reverse osmosis device should be treated with biochemical treatment system and be discharged after meeting the standards.

　　Heavy metal wastewater treatment

　　III. Heavy Metal Wastewater Treatment Process

　　The high-precision heavy metal removal technology of Shangchen Environment performs precise pH and ORP control based on the different reaction conditions of various heavy metal ions. After the reagent is added to fully react with the wastewater, it enters the precisely controlled high-efficiency precipitation system to form solid-liquid separation, and then is filtered through a high-efficiency filtration system. Subsequently, heavy metal capture or special-effect resins can be added for in-depth treatment to ensure the removal of heavy metals.

　　● Set online monitoring instruments such as pH and ORP to automatically control the metering pump for quantitative dosing.

　　● Set high-efficiency stirring system to effectively improve the mixing effect, speed and uniformity, ensure full reaction of the reagents, and the reaction speed is 15 times that of air stirring.

　　● Precisely control the efficient sedimentation, adopt special corrugated inclined plate filler, which can increase hydraulic load, save space, and reduce the collapse of plate caused by excessive flocs.

　　● The high-efficiency filter media is subject to the combination of various filter media, the pollution holding capacity is 3 times that of ordinary sand filters, and the backwashing interval is long.