PROCEDE ET APPAREIL POUR CONVERTIR LES DECHETS ANIMAUX EN ALIMENTS DE COMPLEMENT

摘要

1352160 Animal feed INTERNATIONAL FARM SYSTEMS INC 17 Dec 1971 [22 Dec 1970 11 Aug 1971 30 Nov 1971] 58674/71 Heading A2B [Also in Division B1] A swine feed supplement is prepared by passing an oxygen-containing gas through a slurry of swine waste, while maintaining the slurry at a temperature of between 75‹F and 100‹F and at a pH of between 4 and 7, until urea is substantially eliminated from the slurry. The supplement may be prepared by using the apparatus of Fig. 1 which comprises an aerating assembly 16 and a rotary agitator 14 formed by two frames 18, 20 each supporting a wire mesh and attached to each other and to a rotatable shaft 26. In operation slurry of water and swine waste products is introduced into vat 12, and, to initially start the conversion process Candida utilis yeast, Balcer's yeast and sugar are also added (the Specification disclose the preferred quantities and ratios of the ingredients). The agitator 14 is rotated at 50 r.p.m. and air is supplied at 100 litres/mm. The temperature of the slurry is maintained preferably between 75‹F and 95‹F, and the pH is maintained preferably between 4.5 and 5. Phosphoric, hydrochloric or other inorganic acids may be added periodically to maintain the pH value. After the conversion process part or all of the batch may be removed from the vat for mixing with a basal feed e.g. corn or bone meal. If only part of the batch is removed further raw swine waste may be added. Alternatively, the treated slurry may be processed for at least 5 mins in a separate vat of a temperature of at least 140‹F to reduce enteric flora and E. coli content. At 180‹F all enteric flora will be inactivated after 30 mins. The separate vat may instead be pressurized and depressurized to destroy the living organisms. In a modified process liquid and solid waste plus run-off drinking water (the amount of which may be controlled) passes directly from pig pen's into an oxidation ditch in which an aerator rotor is provided. The slurry is then pumped into a vat in which it is agitated and aerated by air delivered via a perforated hose at a minimum temperature of 29‹C. A thermostatically controlled heating mantle maintains the slurry in the vat at or above the minimum temperature.