What are the different advantages of various fermentation and composting technologies and organic fertilizer fermentation tanks

With the development of aquaculture in China, the amount of livestock manure is also increasing. In 2020, the total amount of livestock and poultry manure in China will reach 3.00 billion tons, exceeding the total amount of solid wastes such as industry and agriculture. The treatment of livestock and poultry manure has become the key to environmental issues. In recent years, China has issued a number of policies to promote the resource utilization of livestock and poultry manure. For example, in 2017, the State Office issued the "Opinions on Accelerating the Resource Utilization of Animal and Poultry Breeding Wastes", vigorously advocating to adhere to the reduction at the source and comprehensively promote the resource utilization of livestock and poultry breeding wastes; In 2019, Zhongnong issued the "Implementation Opinions on Doing a Good Job in Agricultural and Rural Work in 2019", vigorously implementing the whole county promotion project for the resource utilization of livestock and poultry manure. It can be seen that the proper treatment of livestock and poultry manure is an inevitable trend in the development of the aquaculture industry, and also a fundamental guarantee for achieving sustainable agricultural development in China.
At present, the main composting technologies for livestock and poultry manure treatment in China are flip stack composting, ventilated static stack composting, fermentation tank composting, and closed tank composting. The treatment process of tipping and stacking compost is simple and requires less investment, but it covers an area of up to, requiring the fermentation of livestock and poultry manure on concrete or other hardened ground to avoid soil pollution. Secondly, this composting process has a long cycle and generally takes about 1 to 3 months depending on the climate; During the fermentation process, due to the outdoor fermentation, it is greatly affected by the weather, and the fermentation is not thorough, which is easy to cause residues of substances such as diseases, insects, and bacteria. Ventilated static stack composting is a composting process formed by adding a ventilation system on the basis of flip flop composting. This fermentation technology has a low investment cost and is less affected by the environment. However, it has a large single floor area, poor ventilation control, and ventilation pipes are prone to corrosion. At the same time, it can also pollute the air and generate toxic gases such as biogas during the composting process; Fermentation tank type composting generally consists of a fermentation tank, mixing machinery, ventilation devices, and fermentation workshops. This type of composting has a relatively small environmental impact, with a composting duration of around 30 to 40 days, and a large processing capacity. However, this fermentation technology has a high investment and a large floor area, and mixing machinery is prone to corrosion, resulting in high equipment maintenance costs.
The closed tank composting technology mainly refers to the organic fertilizer fermentation tank technology. The organic fertilizer fermentation tank adopts the principle of aerobic microbial fermentation, enabling microorganisms to utilize the organic matter and residual protein in livestock and poultry feces and carcasses, and rapidly reproduce under a certain temperature, humidity, and sufficient oxygen environment, thereby achieving harmless treatment of livestock and poultry waste. The main advantages are as follows:
1. Tank Closure: The tank is fully enclosed, and the fermentation process is not affected by the natural environment, making the organic fertilizer production meet industrial production standards, preventing the leakage of waste gas generated by fermentation, and eliminating secondary pollution;
2. Heat insulation treatment: Polyurethane is used as an insulation layer inside the tank, which is less affected by the external environment, ensuring fermentation throughout the year;
3. Drive design: hydraulic drive with large thrust can ensure full load operation of the decomposed substances in the tank, ensuring stable operation;
4. Energy saving design: Through a heat exchange treatment system, the thermal controlled gas in the tank is circulated for fermentation, reducing energy consumption, and improving energy utilization;
5. Long service life: The inner walls of the tank are all made of 304 corrosion-resistant stainless steel, which has a long service life;
6. Simple operation: electric control, automatic and manual double combination mode, easy to operate, easy to learn, save labor costs;
7. Floor space saving: This equipment adopts a vertical closed tank structure, which saves floor space and can be installed outdoors without requiring a factory building.