The water treatment agent- polyaluminium chloride (abbreviated as PAC) is inorganic high molecular polymer and is made from high grade calcium aluminate powder and hydrochloric acid. Function and use 1). It is used widely for purifying drinking water and industrial water.2). It is featured with fast response, less agent consumption, large alum flower, fast sedimentation, good filtration. It can increase equipment availability and reduce water treatment cost.3). Over dosage may not create side effect. It is easy handling and management, not corrosive on water treatment equipment and pipes. Scope of application The agent is suitable to the water with PH value of 4 to 14, but the optimal treatment scope is PH value of 6-8. Its adaptive capacity is good so that it can purify different kinds of water and has solved the difficulties encountered by other agents, such as slow response and poor effect in low turbid water and low temperature water (lower than 4℃). Operation method and precautions 1). In accordance with different situation of raw water, a test shall be conducted before using it so as to calculate optimal dose. The solution for test is prepared by weight volume ratio (W/V) , 2～5% is advisable in general. If 3% solution is needed, put 3g of PAC into a clean 200 ml beaker; add about 50 ml of clear water. After PAC is dissolved, add water up to 100 ml scale on the beaker. Shake the beaker and the solution is prepared well.2). In formal production, PAC and clear water in 1:5 are mixed together first; then add water further to dilute the solution to 2～3%(W/V) of concentration. The solution with less than 1% of concentration is easy to be hydrolyzed and its performance may be reduced. The solution with too large concentration is wasteful.3). Add proper quantity of PAC; keep observation and make adjustment while adding. If alum flowers are few in settling tank and residue turbid is high, the dosage is too small. If settling alum flowers are large and upturned, as well as the residue turbid is high, the dosage is too large. The dosage shall be adjusted properly.4). Dosing facility shall be corrosion resistant and the PAC is applicable to all water treatment facilities. Install , transport and store the request