Biological organic fertiliser prepd. from refuse - by three-stage fermentation process

摘要

Prepn. of fertilisers from solid town refuse and organic waste of any origin, size and compsn. comprises biological transformation at pH 4-8.5, a moisture content of 45-60% and a C/N ratio 25-35:1, in a plant which permits turning of the mass and its natural aeration which is controlled to give a temp. of 65-68 degrees C, and contg. the treatment until the pH stabilises at about 7 and until, in the 24 hr. after the maximal temp. has been reached, the temp. does not rise =10 degrees C above that in the same part of the previous cycle. The partially fermented mass produced is then fermented anaerobically, but sheltered from the weather, in the form of bales which are turned and replaced each time a fall in temp. follows an initial rise, fermentation being complete when the rise in temp. after turning the bale is lower by 5-10 degrees C than the temp. in the preceding cycle. The obtd. mass is fermented after addn. of a microbial culture, isolated from the mass itself, which is a thermophilic organism with high degrading activity on the main organic substances such as cellulose, starch, protein, pectin, etc., fermentation continuing until the C/N ratio is stable.