Study On The Activated Carbon Produced With Sewage Sludge

In resent years, the quantity and the scale of municipal wastewater treatment plants are increasing rapidly due to the rapid urbanization and higher effluent criteria. In the meantime, large amounts of sludge are produced. Without proper treatment and disposal, it will cause a secondary pollution problem in the environment. Sewage sludge is rich in carbonaceous organic material, therefore it has the potential to be converted into activated carbon if pyrolysed under controlled conditions or with some chemical treatment. This conversion will offer the combined benefits of reducing the volume of sewage sludge to be disposed of and producing a valuable adsorbent with lower cost than commercial activated carbons.This paper proposes a chemically activated method to utilize the digested sludge to make up activated carbon. The optimal operating conditions were determined through experiments. The kinds of activated agent, the activation agent concentration, the activation temperature, the activation time and the ratio of solid to liquid were chosen as impact factors. BET surface area, pore size distribution, SEM photography, weight-loss curve and FT-IR were analyzed to evaluate the performance of sludge activated carbon and discuss the preparation process and mechanism. Carry on research of the adsorption of methylene blue on sludge activated carbon thermodynamics and dynamics. The sludge activated carbon was used to adsorb synthesized wastewater and actual dyestuff wastewater, and then the regeneration of the used sludge activated carbon was studied. The experimental results showed that:As potential adsorbents, sewage sludge was pyrolyzed, chemically activated by ZnCl₂ and H₂SO₄ respectively. Iodine and methylene blue were used in order to characterize the adsorption capacity of the different adsorbents, and the adsorption capacity of ACz is the best. The highest surface area of ACz is 458m²Â·g^-1, and the average pore diameter is the smallest. The highest surface area of ACs is 209m²Â·g^-1, and the proportion of mesopores is more. The surface area of ACp is 98m²Â·g^-1, and the...