Acid pickling wastewater tank and wastewater treatment equipment of Xichang Silicon Mine Corrosion protection material - acid resistant and heavy anti-corrosion

Acid cleaning is a key link in the purification of high-purity quartz placer, especially in the preparation of high-purity quartz sand raw materials for glass manufacturing. This process mainly makes use of the characteristic that quartz is insoluble in acid, while other impurity minerals can be effectively dissolved by acid solution, so as to realize the purification of quartz. Common acids include hydrofluoric acid, * * *, hydrochloric acid, oxalic acid and * * *, etc. The specific acid concentration depends on the type and content of impurities in quartz sand.

In the process of treatment, acid washing wastewater is a major treatment focus, including acid washing sediment, deacidification wastewater, tank washing wastewater, dehydration wastewater after water washing and quartz sand storage percolation wastewater. In order to deal with the challenges brought by these wastewater, we have adopted ZS-1033 special acid resistant coating. This kind of coating is elaborately processed from more than 20 kinds of materials, such as phenol formaldehyde plus fluorine densification modified resin, barite, nano graphite flake, etc. Its cured coating shows excellent properties such as high inertia, large chemical steric resistance, compactness, strong acid and alkali resistance, and low moisture permeability coefficient. It can effectively prevent the corrosion of hydrofluoric acid of various concentrations, and can also resist the corrosion of various strong acids, strong bases, salts, intermediates and organic additives, such as hydrochloric acid, * * *, * * *, oxalic acid, phosphoric acid, * * *, soda ash, * * *, sodium chloride, calcium chloride, etc.

When hydrofluoric acid is used as the main pickling medium, the core task of wastewater treatment is to remove F ions. At present, we mainly use sedimentation method and adsorption method to treat this kind of wastewater. The treatment process will be adjusted according to the different fluoride concentration. Flocculation sedimentation method or adsorption method can be directly used to treat low concentration fluoride wastewater; For high concentration fluoride containing wastewater, lime milk is first added for calcium fluoride precipitation to reduce the fluoride content to below 50mg/L, and then flocculant is added to further reduce the fluoride content to below 10mg/L.

The main pollution factor of pickling wastewater is F -, we mainly add Ca2 to convert fluoride into sediment, and then remove it through coagulation and sedimentation, so as to ensure that the treated wastewater meets the discharge standard or can be reused. The whole treatment process is divided into two stages of sedimentation: the first stage sedimentation mainly removes most of the fluoride ions in the wastewater, and the treatment capacity reaches more than 90%; The secondary precipitation will further remove the remaining fluoride ion to reduce its content below 10mg/L, so as to meet the emission requirements of fluoride ion.

In the acid cleaning sand wastewater treatment process, we also use ZS-1033 hydrofluoric acid resistant anti-corrosion coating to protect various metal pools (tanks) and other equipment. For the concrete pool, we first use ZS-1011 oily transition coating for priming treatment, and then apply ZS-1033 coating. In addition, for other tanks with high acid and alkali dosing concentration, we can also choose ZS-1032 strong oxidation resistant anti-corrosion coating or ZS-1034 acid and alkali resistant anti-corrosion coating for protection to ensure long-term stable operation of equipment.