A Parametric Study of Dewatering of Fine Coal

Abstract

A study using an experimental design of pressure filtration for fine coal dewatering is presented. The effects of five major process parameters of the dewatering, i.e. applied pressure, filtration time, cake thickness, solids concentration and slurry pH, on cake moisture reduction and air consumption were investigated. The study was conducted starting with two level factorial experiments to identify the most significant parameters in the filtration process, and concluding with response surface methodologies to establish an optimum operating condition for the dewatering of fine coal with these significant variables. It was observed that applied pressure, cake thickness and filtration time were identified to be the key operating variables for reduction of moisture content of the filter cake as well as air consumption. With the key parameters, an operating process condition for the dewatering that provided satisfactory performance was determined to be an applied pressure of 93 psi (6.4 bar) with a cake thickness of 2.5 cm and a filtration time of 4.8 minutes for this specific laboratory filtration system. At the optimum process condition the filter cake containing about 22 percent moisture by weight was obtained and the air was consumed by 4.1 m ¹ /(m ² .min.kg) on dry solid basis.

Key words:

• Pressure filtration
• fine coal dewatering. factorial design
• response surface methodology

Additional information

Notes on contributors

B. K. PAREKH

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