PRESSURE LOSS REDUCING DEVICE IN PIPE CONVEYANCE OF SLUDGE CAKE

摘要

PROBLEM TO BE SOLVED: To reduce pressure loss of a highly viscous substance, feed it under pressure, and convey it over a long distance by providing a projection body consisting of a gradually shrinking part whose diameter is gradually shrunk along the direction of a stream and an expansion part whose diameter is abruptly or slowly expanded on an inner side of a pipe which feeds the highly viscous substance such as sludge cake under pressure. ;SOLUTION: A projection body 3 formed by a tapered gradually shrinking part 4 whose diameter is gradually shrunk from an inlet side toward an outlet side and an expansion part 5a whose diameter is stepwise expanded from its terminal is provided toward an inner side on inner periphery of a restriction pipe 2 which restricts dewatered cake which is being conveyed and is provided on the halfway of a pipe 1. At this time, a sludge cake 6 which is fed under pressure in the pipe 1 and enters the restriction pipe 2 comes into contact with the gradually shrinking part 4 of the projection body 3, moves, is gradually restricted, and is fed under pressure. The sludge cake 6 which advances from the gradually shrinking part 4 to the expansion part 5a is decompressed, and air mixed into the sludge cake enters a clearance between an inner face of a pipe and the sludge cake to reduce friction resistance and conveyance pressure.;COPYRIGHT: (C)1998,JPO