摘要 |
The method maximises available heat transfer surfaces during heat exchange process carried out in closed tubular channels between two roughly equally pressurised laminar flows of aqueous suspensions. The suspension solids content is more that 6 weight % and a large part of the solids comprises cellulose, textile or mineral fibres. Heat transport from one suspension flow to the other is achieved using a pumped counter flow cycle of a recirculating intermediate flow system comprising e.g. water, the counter flow being roughly as great as the two suspension flows. A sloping plate replaces the boundary layer of the laminar flow of the two suspension and intermediate flow cycles on each side of the plate with the central layer of the flow, resulting in a more uniform temperature distribution. The angle of the plate in relation to the flows is used to achieve a change in flow direction without the formation of a dead zone immediately downstream from the plate. |