How to treat the industrial wastewater produced by mineral processing reagents
The pollution effect of mineral processing reagents on ecological environment is very complex, which has direct harm or indirect harm. Next, let's learn how to treat the industrial wastewater produced by mineral processing agents.
The pollutants in mineral processing wastewater mainly include suspended solids, acid and alkali, heavy metals, beneficiation reagents, chemical oxygen consumption substances, etc. According to the pollutants in wastewater, different treatment methods can be adopted. Suspended solids mainly adopt pre precipitation and coagulation / sedimentation methods; acid-base wastewater adopts mutual neutralization method; heavy metal ions can adopt co precipitation technology, adsorption technology, ion exchange method, etc.; chemical oxygen consumption materials can adopt coagulation / precipitation, biodegradation, oxidation, adsorption, etc.
1. Adding reagent precipitation: the grinding particle size of some mineral processing agents is too fine or the fine tailings are suspended in the tailings water after adding some mineral processing agents, which can not be clarified for a long time, so chemical agents need to be added for treatment. The chemical agents mostly use No. 3 flocculant or lime. For example, mineral water contains sodium silicate and oleic acid, and fine tailings are suspended in water and cannot be clarified for a long time. After adding lime, good clarification effect is obtained. The dosage of lime is about 0.3-0.5% of the pulp.
2. Natural precipitation: the mineral processing reagent contains suspended solids, including tailings, wet dust collection and washing surface water. The tailings water is generally precipitated by tailings pond, while the wet dust collection and washing surface water is precipitated by sedimentation tank or concentration tank. When the supernatant after solid-liquid separation is reused for production or the water quality meets the discharge standard, it is directly discharged. The aerobic treatment wastewater is separated from liquid and solid by natural sedimentation in the sedimentation tank to obtain the discharged wastewater and sludge. A small part of the sludge is sent back to the contact oxidation tank, and most of the sludge is sent to the sludge thickening tank.