Community Research and Development Information Service - CORDIS


This project was used to identify economic methods of reducing the moisture content of fine coal within a power station blend. Tests on various vacuum filters showed the horizontal belt filter to have double the specific throughput of a conventional rotary vacuum filter (RVF) with a small improvement in cake moisture. The Valmet filter gave a significant moisture reduction compared with an RVF, but with a low specific throughput. Trials aimed at increasing its throughput showed the Diastar filter to be useful for thickening the feed to subsequent dewatering operations. Pilot scale tests were carried out on an air blown press, and a full scale press was installed at a working colliery. Tests on a number of different hyperbaric filters showed them to be capable of producing a low moisture product or a high specific throughput or any optimum intermediate combination. The performance of a high pressure tube press was evaluated over a long period at a colliery site. It consistently produced a hard brittle cake capable of being handled in any proportions in a blend. A high speed centrifuge used in the sugar industry was tested and gave a low moisture product. The machine is potentially a very cheap dewatering device, if the problem of very high rates of screen wear can be resolved. Chemical dewatering aids gave no significant reduction in product moisture. Detailed calculations of dewatering costs have enabled a table of comparative costs to be drawn up for the machines tested. This has led to suggestions for circuit modifications to obtain more economic dewatering of flotation concentrate.

Additional information

Authors: BRITISH COAL CORPORATION HQTD, British Coal Corporation HQTD, Burton upon Trent (GB)
Bibliographic Reference: EUR 13549 EN (1991) 152 pp., MF, ECU 8, blow-up copy ECU 20
Availability: (2)
Record Number: 199111041 / Last updated on: 1994-12-02
Original language: en
Available languages: en