The source and classification of organic fertilizer raw materials

There are many raw materials for composting to produce organic fertilizer, which can be distinguished according to the following methods:

1. Classification by source of raw materials

(1) Crop straw and other plant residues. This part of the plant sources mainly include straw, wheat straw, corn stalk, garden waste and so on.

(2) Livestock and poultry manure. Such as pig manure, cow manure, sheep manure and other breeding manure.

(3) scraps of agricultural and sideline products. Such as soybean meal, rapeseed meal, monosodium glutamate residue, mushroom residue, etc.

(4) Residents’ domestic garbage. Such as kitchen waste, plant ash, etc.

(5) Other raw materials. Such as biogas residue, peat, plant ash, silt, urban domestic sludge, etc.

2. Classification according to primary and secondary functions

(1) Main raw materials. Usually the main raw material accounts for 30%-80% of the whole material, which is composed of one or several kinds of raw materials. Commonly used main materials are livestock and poultry manure, straw powder, mushroom residue and so on.

(2) Accessories. It is mainly used to adjust some raw materials of moisture, carbon-nitrogen ratio, PH value and permeability, and is composed of one or several raw materials. Usually, such raw materials account for less than 40% of the entire material, and the proportion of a single material does not exceed 20%. Commonly used excipients are wheat bran, soybean meal, peat, grass ash, quicklime and so on.

3. Classification according to the properties of raw materials According to the properties of raw materials, it can be divided into carbon-containing raw materials, nitrogen-containing raw materials and conditioner raw materials.

(1) Carbon-containing raw materials. It refers to raw materials with high organic carbon content, which are usually used as the main material of compost, such as straw, rice husk, mushroom residue, etc. Except for straw compost, most carbon-containing raw materials are used as auxiliary materials to adjust moisture, carbon-nitrogen ratio, bulk density and enhance the permeability of materials.

(2) Nitrogen-containing raw materials. Generally, it refers to raw materials with a carbon-nitrogen ratio below 30:1, such as livestock and poultry manure; there are also some high-nitrogen raw materials that are used as accessories to adjust the carbon-nitrogen ratio, such as soybean meal, fish meal, etc.

(3) Conditioner raw materials. Mainly refers to the raw materials used to adjust the pH value, such as quicklime to adjust the acidity, gypsum to adjust the alkalinity, etc. Sometimes the raw materials for adjusting the carbon-nitrogen ratio are summarized as regulators, such as superphosphate, phosphate rock powder, etc.