In order to find a clarification technology, which is simple in technique, convenient in operation and management, and has durable equipments; a multi grading coarse filter bed, comprehensive clarification technology with slow filtration, is experimentally researched. According to the designed experimental process, the two kinds of raw water with different water qualities are assayed. The phenol is assayed by using ampyrone and direct photometry; the ammonia and nitrogen is assayed by using pretreatment method of the distillation titration method; the dissolution oxygen is assayed by using iod...
