A method for efficient purification of biogas slurry based on algae-bacteria symbiosis

Abstract

The invention provides a fungus-algae symbiosis-based high-efficiency biogas liquid purifying method. The fungus-algae symbiosis-based high-efficiency biogas liquid purifying method comprises the following steps: a, taking biogas liquid, inoculating active sludge, performing aeration treatment until the pH falls to 6.5 to 7.0 and naturally settling to obtain supernate 1; b, inoculating microalgae into the supernate 1 obtained in the step a, culturing and naturally settling to obtain precipitate and supernate 2, wherein the precipitate is microalgae bacteria; c, discharging the supernate 2 obtained in the step b into a vascular plant reaction tank and standing for 5 to 10 days.

Description

technical field [0001] The invention belongs to the field of environmental protection and the field of renewable energy, and in particular relates to a method for efficiently purifying biogas slurry based on the symbiosis of algae and bacteria. Background technique [0002] Biogas slurry, also known as "anaerobic fermentation liquid", is the residual liquid after anaerobic fermentation of poultry manure, straw and other organic matter. It is rich in nitrogen, phosphorus and other substances, especially the high content of ammonia nitrogen, which is regarded as high Concentrated sewage, direct discharge will lead to eutrophication of the water body and pollute the water source. With the vigorous development of biogas projects in my country, a large amount of biogas slurry discharged has become a source of environmental pollution that cannot be ignored, and has also become one of the main bottlenecks affecting the development of the biogas industry. [0003] Biogas slurry tre...

AI Technical Summary

Problems solved by technology

[0005] However, the technology of treating biogas slurry based on microalgae cultivation is not yet perfect, and still faces three major problems: First, the high content of ammonia nitrogen in the biogas slurry will inhibit the growth of microalgae, and the process of aeration or stirring will make the biogas slurry CO 2 Precipitation, pH rise, thereby increasing the concentration of free ammonia and inhibiting the growth of microalgae. At present, dilution method, chemical precipitation method and other treatments are mainly used, and the cost is high; the second is that the content of suspended solids in the biogas slurry is high and the transparency is low. , affecting the growth of microalgae, the methods currently used are mainly filtration and centrifugation, and the cost is high; the third is that the microalgae cells are small (generally 3-30 μm in diameter), and it is difficult to harvest after processing biogas slurry. If the centrifugal method is used to harvest energy High consumption, high operating cost, and low filtration efficiency are not conducive to large-scale process applications

[0006] There is currently no effective solution to the aforementioned problems

Images