Preparation method of sludge-based charcoal slow-release phosphate fertilizer and sludge-based charcoal slow-release phosphate fertilizer

Abstract

The invention discloses a preparation method of a sludge-based charcoal slow-release phosphate fertilizer, which comprises: adding a conditioner into sludge, and uniformly stirring to obtain conditioned sludge; placing the conditioned sludge into a hydrothermal reactor, sealing, and heating to perform a hydrothermal carbonization reaction so as to obtain hydrothermal carbonated solution; carrying out solid-liquid separation on the hydrothermal carbonated solution, washing a solid product, and drying at a temperature of 40 to 60 DEG C to obtain sludge-based charcoal; placing the sludge-based charcoal into phosphate solution, after oscillating for 16 to 48h at a speed of 100 to 200r/min, carrying out solid-liquid separation, and drying a solid product at a temperature of 40 to 60 DEG C to obtain the sludge-based charcoal slow-release phosphate fertilizer. The invention further discloses a sludge-based charcoal slow-release phosphate fertilizer. The preparation method of the sludge-based charcoal slow-release phosphate fertilizer, which is disclosed by the invention, is low in cost, high in processing efficiency and high in solid yield; the charcoal slow-release phosphate fertilizer disclosed by the invention is slowly released, effectively prevents pollution of the fertilizer to the environment, and can improve solid and prevent soil hardening.

Description

technical field [0001] The invention relates to the field of regeneration treatment and resource utilization of sludge, in particular to a preparation method of sludge-based biochar slow-release phosphate fertilizer and sludge-based biochar slow-release phosphate fertilizer. Background technique [0002] With the development of urbanization and the improvement of sewage treatment capacity, urban surplus sludge as a by-product of sewage treatment plants has increasingly become a new problem that cannot be ignored. According to statistics, as of June 2015, Guangdong Province has built a total of 487 sewage treatment facilities, with a daily processing capacity of 24.13 million tons, and an annual sludge production of about 3.62 million tons (water content 80%). There are still nearly 50 sewage treatment facilities in the province. % sludge still to be treated. Sludge is the final product of the sewage treatment process. The water content of most municipal sludge is still as h...

AI Technical Summary

Problems solved by technology

However, these current methods have disadvantages. For high-temperature incineration and thermal cracking, the raw materials need to be dried in advance. However, the current moisture content of most municipal sludge is still as high as 80%. The basic requirements of the basic requirements, it needs to consume more energy and economic costs for high-intensity drying treatment; for microbial fermentation, the treatment cycle is longer, so the process is difficult to control

That is to say, the current method of preparing biochar from sludge has high energy consumption and long treatment cycle, resulting in high cost and difficult process control

This further leads to higher energy consumption and longer treatment cycle when using sludge to prepare slow-release fertilizer, which leads to higher cost and difficult control of the process