Plug flow type bioleaching process and apparatus for sludge treatment

Abstract

The invention provides a plug-flow type bioleaching treatment process for sludge treatment and equipment thereof. The equipment comprises a sludge regulating reservoir, an activating tank, a plug-flow type bioleaching reactor, an advection type sludge concentrated tank, a heavy metal recovery pond and other facilities, an aeration device, a heating device, a dehydration device, a stirring device and other devices. The process comprises the following steps that: a sludge system is acidified by a composite bacterium consisting of a thiobacillus and an acid resistant heterotrophic bacterium under conditions of aerobism and existence of sulfur powder and other composite nutriments, heavy metal in the sludge is massively dissolved in liquid phase, the sludge is regulated at the same time so as to facilitate sedimentation and dehydration; the sludge stays in the reactor for 2 to 4 days; discharged treated sludge enters the concentrated tank to be subjected to gravity thickening; 20 to 50 percent of concentrated bioleaching sludge flows back to the reactor, and the rest sludge is subjected to chamber filtration and dehydration without adding any flocculating agent until the water ratio is below 60 percent; and the heavy metal in the water is recycled by an alkali precipitation method. The method can remove massive heavy metals of the sludge, has over 99 percent of sludge pathogen kill ratio, and ensures that the treated sludge does not have malodor and is in khaki color, thereby realizing the aims of innoxiousness and minimization of the sludge.

Description

1. Technical field: [0001] The invention relates to a method for removing heavy metals in organic waste such as municipal sewage (silt) sludge, industrial sewage (silt) sludge, river and lake sludge, livestock and poultry manure, improving dehydration performance, and realizing high dryness dehydration of sewage (silt) sludge. It belongs to the field of environmental engineering technology. 2. Technical background: [0002] According to statistics, by the end of March 2008, 1,320 urban sewage treatment plants had been put into operation across the country, with a treatment capacity of 97.25 million M 3 / day, there are 890 urban sewage treatment plants under construction, with a treatment capacity of 36.39 million tons / day, and the sewage (silt) sludge production rate is 1.5 dry tons of sewage (silt) sludge / 10,000 M 3 In terms of sewage, the current annual output of sewage (silt) mud in my country reaches 5.32 million tons of dry weight, which is equivalent to nearly 30 mill...

AI Technical Summary

Problems solved by technology

Their existence limits the rational utilization of sewage (silt) mud

[0008] 3. Due to the high content of organic matter, the sludge (silt) is easily corrupted, and there are many sulfur-containing substances (hydrogen sulfide, mercaptan, sulfide, etc.), ammonia or putrescine, low-molecular-weight volatile fatty acids, etc., and the stench is obvious; and usually contain a large number of pathogenic microorganisms, therefore, poor sanitation

However, reactors operated in batch mode (such as air lift type) are usually small in size, high in automation and technical requirements, and relatively large in investment and operating costs.

Images