Sludge dewatering subjected to constant vacuum pressure: a modelling approach

Sludge is often generated from the treatment of wastewater and it is essential to reduce its volume before disposal into the environment through dewatering. This helps to reduce the cost of final sludge disposal. This study was therefore aimed at developing a model for the draining time of sludge through the application of vacuum pressure. A vacuum filtration experiment was performed on sewage sludge collected from the wastewater treatment plant situated at the University of Nigeria, Nsukka. The sludge sample was poured into Buchner funnel apparatus and the volume of the filtrate collected was noted at a certain time interval until the end of the experiment. The specific resistance values were obtained using the newly derived-, modified-, and Carman’s-equation, respectively. A comparative study was carried out on the three values obtained and the results showed that the newly derived equation gave the best result. Overall, the newly derived equation demonstrated conformity with Carman’s equation and can be used for sludge dewatering investigation. This paper covers a relevant subject within the field of waste treatment processes, namely the dewatering of sludge from wastewater treatment system and on a large scale, can aid in producing cost effective mechanism that makes it more possible for developing nations to incorporate adequate and effective sanitation.