Method of filter-pressing sludge of concentration tank and septic tank of sewage plant

The invention relates to a dewatering treatment of a pollutant, in particular to a method of filter-pressing sludge of a concentration tank and a septic tank of a sewage plant. The method comprises the steps of: (1) sending sludge in the concentration tank and the septic tank into a dispensing tank, firstly adding a ferric trichloride solution of which a dry sludge mass is 15%, secondly adding a calcined lime of which a dry sludge mass is 10% to stir and perform dispensing, and (2) conducting filter-pressing treatment to obtain block-shaped sludge of which a moisture content is 35-60%. With the adoption of the dewatering treatment, existing filter-pressing process is changed; though the process of adding water to dilute is only saved during the process, and the generation of secondary filter-pressing is directly avoided, so that the maximization of the economic benefit and the work efficiency is greatly achieved.