Filter unit for avoiding environmental pollution in cemeteries

Claim 1

A filter for removing harmful gases and unpleasant odors from decomposing corpses, said filter comprising an elongated container hermetically sealed at one end and having a perforated inlet extending substantially across the opposite end, an exit duct projecting through said perforated inlet and extending through substantially the entire length of said container to terminate just short of said hermetically sealed end whereby gases entering the container through said perforated inlet end pass through substantially the entire container length before entering the exit duct for passage in the reverse direction for venting to atmosphere, first separator means located within said container and extending around said exit duct and diametrically across said container substantially to isolate a first compartment within said container proximate said perforated inlet end containing inert and porous material to filter large particles and retain the contents of the container in position, second separator means located downstream of the first separator means in the gas flow direction substantially to isolate a second compartment containing oxalic acid to remove amines from the gas flow, third separator means located downstream of the second separator means in the gas flow direction substantially to isolate a third compartment containing a metallic salt selected from the group consisting of copper sulphate, mercuric chloride and lead acetate to remove sulfur components from the gas flow and activated charcoal disposed between said third separator means and said hermetically sealed end of the container to envelop the entrance end of the exit duct and remove remaining unpleasant odorous gases.