Vapor control system for vapor degreasing/defluxing equipment

摘要

An improved vapor degreaser characterized by a deep freeboard zone (i. e., freeboard to width ratio of 1.0 to 2.3) containing a three- stage condenser/heat exchanger configuration comprising: a water-cooled lower primary exchanger operating above 32° F. to effect condensation of the bulk of the vapor generated by the boiling sump and a combination of an intermediate exchanger above, but preferably overlapping, the primary exchanger and a dehumidifying third exchanger position just below the top lip of the degreaser, both operating at a temperature below 32° F. (preferably +10° to -30° F.) to effect a reduction in the vapor concentration gradient that controls the rate of vapor diffusion through the freeboard zone. The improved vapor degreaser is particularly useful in reducing vapor losses when using low boiling solvents.