Why should compost be crushed and screened before fermentation
Date:2020/03/04
When using livestock manure and sludge as composting raw materials, the main task of the early fertilizer production process is to adjust the water and C / N ratio, or add bacteria and enzyme. However, when municipal solid waste is used as composting raw material, there is a pre-treatment process of crushing and sorting because there is a large amount of non composting material in the waste. Through crushing and sorting, the non composting material is removed and the particle size of the waste is adjusted.
The reasons why non compost materials must be removed are as follows:
① If not removed, the volume of fermentation bin will increase;
② The conveyor or compost windrow turner may be wound by fibers or ropes or twisted by bamboo, metal, etc., which may affect the operation;
③ Non compost materials hinder the fermentation process;
④ Although non composting materials can also be removed in the post-treatment process, the heavy metals contained in dry cells and other materials, once mixed with composting materials, can not be selected in the post-treatment, but mixed into the finished compost.
The water content of raw materials can be homogenized to a certain extent by the organic fertilizer machine crushing, and the surface area of raw materials can be increased by crushing, so the speed of microbial erosion will be accelerated, and the fermentation speed can be increased. Theoretically, the smaller the particle size is, the easier it is to decompose. However, in consideration of increasing the surface area of the material, it is necessary to ensure that the material has a certain porosity, which is convenient for ventilation, so that the material can obtain sufficient oxygen.
Generally, the suitable particle size range is 2-60mm, and the optimal particle size changes with the change of the physical characteristics of garbage. If the compost material structure is solid and not easy to be extruded, the particle size should be smaller, otherwise, the particle size should be larger. In addition, when determining the size of garbage particles, we should also consider the economy, because the smaller the crushing is, the greater the power consumption is, and the cost of garbage treatment will increase.
The reasons why non compost materials must be removed are as follows:
① If not removed, the volume of fermentation bin will increase;
② The conveyor or compost windrow turner may be wound by fibers or ropes or twisted by bamboo, metal, etc., which may affect the operation;
③ Non compost materials hinder the fermentation process;
④ Although non composting materials can also be removed in the post-treatment process, the heavy metals contained in dry cells and other materials, once mixed with composting materials, can not be selected in the post-treatment, but mixed into the finished compost.
The water content of raw materials can be homogenized to a certain extent by the organic fertilizer machine crushing, and the surface area of raw materials can be increased by crushing, so the speed of microbial erosion will be accelerated, and the fermentation speed can be increased. Theoretically, the smaller the particle size is, the easier it is to decompose. However, in consideration of increasing the surface area of the material, it is necessary to ensure that the material has a certain porosity, which is convenient for ventilation, so that the material can obtain sufficient oxygen.
Generally, the suitable particle size range is 2-60mm, and the optimal particle size changes with the change of the physical characteristics of garbage. If the compost material structure is solid and not easy to be extruded, the particle size should be smaller, otherwise, the particle size should be larger. In addition, when determining the size of garbage particles, we should also consider the economy, because the smaller the crushing is, the greater the power consumption is, and the cost of garbage treatment will increase.