Waste water heat exchanger

摘要

A waste water heat exchanger comprises of an inner cylinder 3 through which waste water flows and an outer cylinder 1 surrounding the inner cylinder 3 and through which a liquid to be heated flows. Couplings 2 at each end of the inner cylinder 3 may be provided and may be connected to a waste water or sewage pipe and have an inner diameter the same size as an inner diameter of the inner cylinder 3. The outer cylinder 1 is closed at each end, sealed to and covers the inner cylinder 3 but does not cover the couplings 2, and may be supplied with liquid via pipes 4. The heat exchanger may be used above and below ground and its material of construction varied accordingly. The thermal conductivity of the material used for the manufacture of the heat exchanger may be of varied. Waste water may flow through the inner cylinder 3 unimpeded and in counter flow to the liquid flowing through outer cylinder 1. Inner cylinder 3 may have ribs inside and/or outside along its length to increase its surface area. Two or more heat exchangers in series may be used and the heat exchanger may be used horizontally or vertically.