Abstract: For the purpose of controlling odor, a slurry of digested sewage sludge to be sprayed on land for restoring its fertility is mixed with a deodorant composition containing glacial acetic acid and amyl alcohol and optionally other components including 2,3-butanedione, sulfuric acid, hydrochloric acid, benzaldehyde and copper sulfate.

Abstract: A process for the chemical treatment of organic waste materials contaminated with a pathogenic microorganism, such as raw sewage, sewage sludge and other organic waste products, and to the treated organic waste material so obtained, which process comprises: prereacting the organic waste material with a water-soluble methylol compound subject to condensation, such as a methylolurea compound, under alkaline pH conditions; and, thereafter, condensing the methylol compound by establishing an acid pH condition to form a solid waste product comprising a condensation polymer containing methylene bridges and a sterile solid waste material.

Abstract: A completely integrated and automated apparatus by which liquid sewage sludge from any sewage or waste treatment plant may be processed into a completely dry, pelletized and sterilized product of an organic nature containing nutrients valuable for the support of plant life. The apparatus involves one completely integrated and automated unit together with a control center by means of which electric circuits program each component of the apparatus to automatically regulate the operation of each component, so that no labor or other manpower is required in the operation, except for observation, lubrication, maintenance and repair of the various motors and machineries involved.

Abstract: Liquid sewage and waste, such as manure and/or sewage sludge, are treated to destroy pathogenic bacteria and remove offensive odors to make the material usable as a plant nutrient and soil conditioner. The liquid sewage is thoroughly aerated within a cone-shaped, pressurized vessel by injection of a jet of compressed air tangentially to the side walls of the vessel into contact with the liquid sewage. The vortex motion and agitation created by injection of the compressed air disintegrates the larger solids of the sewage or sludge so that the compressed air can permeate the material to a greater degree. A head of compressed air is built up above the liquid level in the pressurized vessel, which, on opening of a discharge valve in the lower end of the pressurized vessel, forces the contents of the vessel through an outlet pipe connected to the vessel through the discharge valve. The material may be used as is or discharged onto a pile of sawdust, ground bark or straw for composting.

Abstract: A biological fertilizer is prepared by a process which comprises treating sewage sedimentation sludge with sulphite waste liquor, the treatment being carried out at a pH of no more than 6, followed by mixing the mixture of treated sludge and waste liquor with pulverized vegetable matter, whereby to form a biological fertilizer.

Abstract: An apparatus for and a process of treating sludge filter cake and the granular product thereof which comprises reducing the particle size and moisture content of the sludge cake, sterilizing the sludge cake by contacting the sludge cake with an N-methylol-urea solution, reacting the N-methylol-urea solution with the sludge cake at a pH of 3 to 5 while agitating the sludge particles to provide a granular-reaction product, and drying the product to provide a granular, high-nitrogen, odorless fertilizer or animal feed supplement product.