The invention relates to a method for preparing an
organic fertilizer through
processing agriculture and
forestry wastes by using an
organic solvent. The method comprises the following steps:
processing the
agriculture and
forestry wastes in high-temperature and high-pressure
organic solvent environment to completely or partially depolymerize
cellulose,
hemicellulose,
lignin and other chemical components in
plant raw materials in order to dissolve above chemical components in a waste liquid, and distilling and
drying the waste liquid to obtain the
solid organic fertilizer and recover the
organic solvent. The
plant raw materials are depolymerized and degraded by the organic
solvent to form the
organic fertilizer which can be easily degraded by microorganisms and absorbed by plants, so the
plant raw materials can improve soil and increase the
fertility. The organic
fertilizer obtained after
processing with the polar organic
solvent has limited
solubility in water, contains abundant phenolic hydroxyl groups, carboxylic groups and other ionizable groups, can be combined with Ca, Mg, B, Zn, Se, Fe, Mn, Cu, Mo and other trace elements, and can be used as a sustained and
controlled release fertilizer. The method converts the
agriculture and
forestry wastes into the organic
fertilizer only through using the organic
solvent without any acid or alkali, so the method has the advantages of low cost and good economic benefit.