Method for removing heavy metals in pig manure by using biochar enhanced indigenous ferrous oxide bacteria

Abstract

The invention discloses a method for removing heavy metals in pig manure by using biochar enhanced indigenous ferrous oxide bacteria; the method can be used for removing heavy metals in the pig manureand other livestock and poultry manure by using the biochar enhanced indigenous ferrous oxide bacteria. Biochar is prepared by carrying out anoxic calcination on wheat straw at 500 DEG C. The methodcomprises the steps of adding the pig manure to be treated into a bioreactor, respectively inoculating 10-15% of indigenous ferrous oxide bacteria and 5-10g / L of biochar, and carrying out aeration treatment for 4-7 days at 30+ / 2 DEG C; pumping out the treated pig manure, dehydrating the pig manure, adjusting the pH of a liquid phase part to precipitate the heavy metals, and neutralizing a solid phase part so as to realize the agricultural utilization of the pig manure. The removal rate of the heavy metals in the pig manure reaches up to 90-98%, and the nutrient loss in the pig manure is reduced by 10% or above. The method is simple and convenient to operate, economically feasible and safe, and is an efficient method for removing the heavy metals in the pig manure.

Description

1. Technical Field [0001] The invention relates to a method for removing heavy metals from pig manure by using biochar to strengthen indigenous ferrous oxidizing bacteria. It uses the redox activity and adsorbability of biochar to promote the growth of ferrous oxidizing bacteria to remove heavy metals in livestock and poultry manure while reducing nutrients The technology of material loss belongs to the field of environmental engineering technology. 2. Background technology [0002] In recent years, with the rapid development of large-scale livestock and poultry breeding, a large amount of livestock manure is produced every year. According to statistics, the output of livestock manure in 2010 was 243 million tons. Since livestock manure is rich in nutrients such as nitrogen, phosphorus, organic matter, etc., it is widely used as agricultural soil fertilizer. However, in the production process of livestock and poultry, in order to promote animal growth, increase feed utilization ...

AI Technical Summary

Problems solved by technology

However, the growth rate of ferrous oxide bacteria is generally slow and the growth cycle is long, and the sludge bioleaching process will cause a large amount of nutrients such as nitrogen and phosphorus to be lost, and the loss rates of total nitrogen (TN) and total phosphorus (TP) can respectively reach 20-33% and 17-68%

[0005] Aiming at the incomplete removal of heavy metals in livestock and poultry feces solidification technology, it is easy to cause secondary pollution, and the conventional bioleaching technology has a long cycle, low removal efficiency, and serious nutrient loss. This project is specially launched to strengthen the ferrous oxide bacteria with biochar. Research on the separation of heavy metals from livestock and poultry manure by bioleaching, in order to provide technical support and engineering practice reference for the removal of heavy metals in livestock and poultry waste in my country, to ensure the harmless resource utilization of livestock and poultry waste in the process of resource utilization, and to provide food production, Provide a strong guarantee for food safety and human health

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