Simulation of sludge dewatering on belt filters

摘要

A mathematical model for belt filters was developed to determine optimum load rate and beltnspeed during drainage of flocculated biological sludge. Numerical simulations were performed fornbelt filters with and without plows, and the model fit experimental data well. Experimentsnshowed that highly compressible cakes were formed during drainage, which was important.nDue to cake compression, the final sludge dry matter content increased with load rates as longnas the drainage time was sufficiently long. The dry matter content could be increased by stackingnthe cake at the end of the process. An optimum load rate was found. At high load rates, thendrainage time was too short and the dry matter content decreased with load due to high cakenresistance. The resistance could be lowered by mixing cake and suspension during the process.