Patent ID: 6550250
Filing Date: 2003-04-22
Classification: B01D,F01N,Y02A,Y02T

Abstract:
A process for reducing the content of nitrogen oxides (NOx) in the exhaust gases of diesel engines or turbines for stationary or mobile applications/vehicles in an SCR system by providing a stored source of liquid reducing agent and feeding the stored reducing agent to the exhaust gases, said process comprising:transferring the liquid reducing agent from the external storage tank to one or more membrane storage tanks, each equipped with an inner bellow consisting of a non-permeable flexible membrane with a hydraulic or pneumatic displacement fluid located outside the inner bellow, wherein the shell of each membrane storage tank is lined on its inner side with foam rubber at least in the area of the flexible membrane to absorb any expansion of the flexible membrane caused by freezing of the liquid reducing agent contained within the flexible inner bellow; filling the flexible inner bellow with the liquid reducing agent and simultaneously exerting pressure on the displacement fluid in the membrane storage tank until the feeding pressure is attained; increasing the pressure of the displacement fluid in the membrane storage tank by transferring more fluid into the volume present outside the flexible inner bellow, and thus forcing the liquid reducing agent to leave the flexible inner bellow; and transferring the liquid reducing agent from the flexible inner bellow to the exhaust gases.