Method for quick start of sludge superhigh temperature anaerobic digestion system with cow dung

Abstract

Belonging to the field of sewage treatment and solid waste recycling, the invention relates to a method for quick start of a sludge superhigh temperature anaerobic digestion system with cow dung. The basic process includes: (1) using a mixture of cow dung and dehydrated sludge in a VS ratio of 1:1 to conduct thermophilic methanobacteria initial enrichment in a 65DEG C anaerobic reactor; (2) mixing a mixture equal to the amount of that in step (1) with the initially enriched material, and conducting thermophilic methanobacteria secondary enrichment; (3) employing a mixture of cow dung and sludge in a VS ratio of 1:1 to start the reactor, controlling the daily adding amount accounting for 5-8% of the total amount in the reactor, and keeping no discharging in the process; and (4) within 3 SRT time, replacing mixed feeding gradually with pure sludge feeding, thus completing start of the sludge superhigh temperature anaerobic digestion reactor. The gas production rate is recorded every day, and the methane content is tested. When pure sludge is fed, and the methane content reaches more than 50%, the reactor start can be considered smooth. Experiments prove that the method can realize quick start of the sludge superhigh temperature anaerobic digestion system.

Description

technical field [0001] The invention relates to a method for quickly starting a sludge ultra-high temperature anaerobic digestion system by using cow dung, and belongs to the fields of sewage treatment and solid waste recycling. Background technique [0002] Anaerobic digestion technology has attracted much attention due to its ability to recover resources and energy from sludge. Most anaerobic digestion systems operate at moderate (35°C) and high temperature (55°C) conditions. Due to the limitation of hydrolysis of organic particles, the degradation rate of organic matter in mesophilic anaerobic digestion is low, and the required SRT is relatively long. During the process of high-temperature anaerobic digestion, the degradation potential of microorganisms has not been fully released. Therefore, improving the efficiency of anaerobic digestion largely depends on the improvement of its hydrolysis efficiency. The optimal temperature for the growth of hydrolytic acidifying bac...

AI Technical Summary

Problems solved by technology

[0004] At present, there are few researches on ultra-high temperature anaerobic digestion at home and abroad, and there is no ultra-high temperature anaerobic digestion system for sludge system

At the same time, due to the few types of thermophilic methanogens and the long generation time, it is difficult to cultivate and reproduce

In addition, the content of organic matter in the sludge is high, the system is complex, and the acidification rate is too fast, resulting in a large amount of VFAs that cannot be effectively used by methanogens, resulting in startup failure.