Two-stage sand removal process for livestock manure

Abstract

The invention belongs to the field of biogas engineering, and particularly relates to a sand removal process for livestock manure. The sand removal process is characterized in that the livestock manure is poured into a stirring settling tank, water is added into the livestock manure to stir and dilute the livestock manure and remove sand in the livestock manure, the sand with the size larger than 0.5mm in the manure is removed, an upper layer of livestock manure diluent overflows to a hydrolytic acidification tank after stirring and sand removal, sand with the size smaller than 0.5mm is separated and removed during hydrolytic acidification, and the hydrolytic acidification tank sequentially consists of a primary hydrolytic acidification tank and a secondary hydrolytic acidification tank from a high position to a low position. The sand removal process has the advantages that by the aid of the two-stage sand removal process, the sand with various sizes in the manure are thoroughly removed, sand content in liquid entering a fermentation tank is reduced to be lower than 2%, influences of the sand to various follow-up links are greatly reduced, and stable running of biogas engineering with the livestock manure as a raw material is guaranteed. In addition, insoluble macromolecular substances in the liquid are degraded into soluble micro-molecule substances which can be easily utilized by methane bacteria, and gas yield efficiency is improved.

Description

technical field [0001] The invention belongs to the field of biogas engineering, and in particular relates to a process for removing sand from livestock and poultry manure. Background technique [0002] Livestock manure has a certain sand content. For example, chicken manure contains sand of various particle sizes, and a certain amount of large particle sand is often fed in chicken feeding to facilitate the digestion of chickens. At the same time, the feed also contains impurities such as stone powder and calcium hydrogen phosphate. These small-sized impurities cannot be completely digested by the chicken, and will be excreted with the feces, and will be combined with the mucus in the digestive tract during the digestion process, increasing the removal efficiency. difficulty. [0003] For biogas projects that use livestock and poultry manure as raw materials, the sand must be removed before the livestock and poultry manure enters the anaerobic tank for fermentation. Sever...

AI Technical Summary

Problems solved by technology

At the same time, the feed also contains impurities such as stone powder and calcium hydrogen phosphate. These small-sized impurities cannot be completely digested by the chicken, and will be excreted with the feces, and will be combined with the mucus in the digestive tract during the digestion process, increasing the removal efficiency. difficulty

[0003] For biogas projects that use livestock and poultry manure as raw materials, the sand must be removed before the livestock and poultry manure enters the anaerobic tank for fermentation. Severe wear and tear, secondly, it will cause blockage of feed pipes and other pipelines, and thirdly, it will cause severe sand settling in hydrolysis tanks, fermentation tanks, etc., increasing the workload of cleaning, and in serious cases, it will affect normal fermentation and gas production

At present, there is not much research on the sand removal of livestock and poultry manure, and there is no effective molding process