Nowadays, many sewage treatment processes are inseparable from polyaluminium chloride. Polyaluminium chloride is also a kind of water purification flocculant, which has a good water purification effect in water treatment. The application range of polyaluminium chloride is very wide. It is not only used for the purification of sewage, wastewater and circulating water, but also for the purification of groundwater, tap water, etc. In recent times, the price of polyaluminium chloride has risen to a large extent. Many customers are complaining that the price is too high, and we are powerless. The surge in the price of upstream raw materials has led to the continuous rise in the price of polyaluminium chloride. Today, our Haoquan polyaluminium chloride manufacturer will explain how to use polyaluminium chloride in coal washing wastewater and the role of polyaluminium chloride in coal washing plants. Coal washing wastewater is wastewater generated in the process of wet coal washing in coal mines. Coal washing wastewater contains a large amount of coal slime and silt, which contains a certain amount of hydrocarbon substances and needs to be purified before discharge. However, it is difficult for coal washing wastewater to settle in a natural state. The stability of suspended matter is good. It is necessary to add coagulants and flocculants to assist coagulation and sedimentation. This method is also the most common method for wastewater treatment in coal washing plants in my country. Xinhuan Polyaluminium Chloride Manufacturer shares with you the knowledge of coal washing wastewater purification principles, the specific details are as follows:
The coal sludge water from the coal washing plant is directly discharged into the coal sludge sedimentation tank for purification. The clarified water can be recycled or discharged. Because the fine coal sludge particles and clay in the coal washing wastewater are difficult to settle, the coal sludge particles are continuously refined during the circulation process, which increases the SS concentration of the circulating water and destroys the coal preparation process. Therefore, the method of diluting the high-concentration coal washing wastewater with clean water and then using it as circulating water is no longer feasible.
The coal washing wastewater is purified by heavy concentration sedimentation, and sedimentation tanks, concentrators and other processes are often used. After the coal sludge water enters the concentrator through the bailing pit, its overflow solid content does not exceed 10g/L[5]. The overflow water is further treated by the sedimentation tank. The surface load of coal washing wastewater treated by sedimentation is low and the area occupied is large. The suspended solids concentration of the wastewater after treatment is still high and cannot meet the wastewater discharge standard.
The coagulation and sedimentation method mainly uses chemical coagulants and flocculants to purify coal-washing wastewater. At present, PAC polyaluminium chloride and PAM polyacrylamide are the most commonly used coagulants and flocculants in coal-washing wastewater purification. According to the different underground coal strata in different regions, the properties of the coal-washing wastewater produced are also different, and experiments are needed to determine the required flocculant model. PAC polyaluminium chloride coagulant is used for coal-washing wastewater treatment. There are three types of drum-type polyaluminium chloride with 26/28/30% content to choose from. The higher the alumina content is between 26-30%, the higher the content, the higher the price of PAC polyaluminium chloride.
PAC polyaluminium chloride for coal-washing wastewater mainly uses the principle of compressing the double electric layer to destabilize the suspended particles in the coal-washing wastewater and produce agglomeration to form small alum flowers. The density of the coal sludge group after adding PAC polyaluminium chloride will decrease, the cohesion between the coal sludge particles will increase, and high-multiple particles will be generated. Such particles have a large void ratio, which leads to a decrease in the effective density e of coal sludge granulation. The effluent turbidity SSt decreases significantly with the increase of PAC dosage, and the effluent changes from turbid to clear; when PAC increases to 2.6 mg/L, SSt changes very little and basically tends to be stable. The increase of PAC increases the destabilization degree of fine particles in coal washing wastewater, increases cohesion, and SSt drops sharply. When the dosage of polyaluminium chloride reaches a certain value, most of the particles in the wastewater are almost completely destabilized and coagulated, achieving the best effect. At this time, there is no need to increase the dosage of PAC polyaluminium chloride, and the dosage of coagulant can be reasonably controlled to save water treatment costs.
The main products of flocculant manufacturer Xinhuan Water Treatment are:
White polyaluminium chloride (food grade), drinking grade polyaluminium chloride, industrial grade polyaluminium chloride, anionic polyacrylamide, cationic polyacrylamide, nonionic polyacrylamide, petroleum recycling polyacrylamide, oil recovery polyacrylamide, polyacrylamide, polymer flocculant polymer flocculation coagulant, polymeric ferrous sulphate, polyferric aluminium chloride and other water treatment chemicals. Welcome customers to write to us to negotiate business! Tel/WhatsApp：+8619003830067 Email：joanna@xhwtm.com Contact:Joanna
