Comparison of dewaterability enhancement for river sediment by adding water transmitting channels in three dewatering procedures

Abstract

The efficiencies of pressure filtration using air pressure (Air-P), suction (Suct-F), and filter pressing (Plate-P) were compared with and without the addition of water transmitting channels (WTCs). From the sediment, with initial water content of 60 ± 0.2 wt% and thickness of 5 cm, dry mud cakes with final water contents of 45.2 ± 0.1 wt%, 43.7 ± 0.1 wt% and 36.2 ± 0.4 wt% were obtained using Air-P, Suct-F and Plate-P respectively with 9 WTCs. The dewatering capacity increased by 100%, 200% and 100% compared to without WTCs. Layer water content analysis of the mud-cake after dewatering indicates that the WTCs added to the Air-P and Plate-P processes mainly enable filtration of free water from the upper layer, whereas the water in the middle and upper layer are sucked and filtered out through the WTCs during the Suct-F process. The water content of the upper layer decreased by 3.3%, 7.3% and 5.2% compared to without WTCs.

Keywords:

• Comparison of pressure filtration methods
• dewatering
• river sediment
• top-to-bottom water transmitting channels (WTCs)

Acknowledgments

Authors thank those students majoring in environmental engineering at Hubei University of Technology who are not afraid of getting dirty and tired. The students helped to get sediment from the smelly river under the hot sun. Second, the authors thank their colleagues for not being driven away from work or complaining about any unpleasant smell emanating from the sediment during the experiments. Finally, the authors express their special thank to those students who came to their team to carry out research. It’s their enthusiasm and persistence in protecting the environment have encouraged authors to work harder and more actively.