Composting and fermentation of fertilizer production process is a process to realize the harmless of organic materials. There are two types of commonly used processes, i.e. stacking process and tank process.
1. Strip and stack fermentation
Stacking composting process is a common aerobic fermentation system, which can decompose raw materials in aerobic condition by stacking them in long strips or stacking.
① Heap shape. The bottom width of the pile is controlled between 120-300cm (or determined according to the width of the crawler compost windrow turner), and the pile height is controlled between 80-200cm, with 120cm as the most appropriate; the length is unlimited. The spacing of each stack is about 80-100cm;
② Composting equipment. It is mainly a stacker tripper: the technical parameters of the main equipment are the maximum allowable stacker height of 200cm, stacker width of 300cm, forward / backward speed of 5-15m / min, and production capacity of not less than 600m3 / h.
2. Trough fermentation
Tank fermentation is a kind of aerobic composting fermentation technology, which combines controlled ventilation and regular turning of piles.
① The size of fermentation tank is usually L × w × H = (60 ~ 100) m × (4 ~ 9) m × (1.5 ~ 2) M. guide rails are laid on the upper part of the tank wall for the convenience of the composter walking; aeration system is laid on the bottom of the tank to ventilate and oxygenate the fermentation materials in the tank, which is mainly composed of high-pressure fans and ventilation pipes.
② The tank type compost turning machine agitates the materials evenly by mechanical agitation, promotes the heat and moisture volatilization, and displaces the materials slowly in the tank. Common organic fertilizer machines include chain plate and agitator, mainly composed of traveling chassis, chain plate (agitator), hydraulic lifting part, transmission part and electric control part.
Tank type organic fertilizer fermentation equipment. The equipment required for tank fermentation is the tank fermentation dumper, which has the advantages of large processing capacity, small land occupation, simple operation, driverless and so on. However, due to the construction of fermentation tank, the fermentation field is fixed, which has certain limitations, and the air permeability is not as good as the strip stack type. At present, based on the function of turning and throwing, some trough fermentation organic fertilizer dumpers are designed with oxygenation devices to increase air permeability; Some add the function of crushing and stirring, which is suitable for fecal type, dregs and fermented products with more fiber and less viscosity. In this way, the pretreatment processes of raw material stirring and crushing can be saved and the production links can be reduced. The trough organic fertilizer dumper is mostly driven by motor because it walks on a fixed track, and its price is mainly related to its motor power.
There are two common composting methods in the granulation of fertilizer production lines
