CN101618933A

CN101618933A - Method for treating sludge of urban sewage treatment plant

Info

Publication number: CN101618933A
Application number: CN200910113336A
Authority: CN
Inventors: 屈智和; 孙大晋
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-05-26
Filing date: 2009-05-26
Publication date: 2010-01-06

Abstract

The invention relates to a technology for harmlessly treating the sludge of an urban domestic sewage treatment plant, which comprises the following steps: after the sludge produced by an urban domestic sewage treatment plant is fully mixed with modified zeolite powders, the water content of the sludge is lower than 30 percent; and the sludge is treated by a drying method or other comprehensive utilization methods, thereby achieving the aim of economic, safe and pollution-free sludge treatment. The invention not only solves the problems of land occupation and secondary pollution of the sludge of the sewage treatment plant, but also reduces the drying cost of the sludge and realizes the harmless treatment and the resource utilization of the sludge.

Description

The method that a kind of sludge from wastewater treatment plant is handled

The present invention relates to the method that a kind of sludge from wastewater treatment plant is handled.

China be one populous, the country of urban compact, there is 688 in large, medium and small city in the whole nation, more than 20,000 of organic towns, about 500,000,000 people of urban population, by the end of the year 2007, annual industry in the whole nation and urban life wastewater emission amount are 600 billion cubic meters, discharged volume of industrial waste water 320 billion cubic meters wherein, town domestic sewage quantity discharged 280 billion cubic meters.

Mud is the throw out that sewage work produces in sewage treatment process, accounts for 0.05～0.1% of sewage total amount usually, is example with the town domestic sewage, and 280 billion cubic meter sewage can produce 1.5 hundred million tons of-3.0 hundred million tons of mud.

Existing sewage work, generally the mode of employing stacking or landfill is handled the mud of generation.The secondary pollution problem that is caused by sludge of sewage treatment plants is on the rise, how the enormous amount that sewage work is produced every day, composition is complicated and with serious pollution mud to carry out harmless treatment and recycling be China and even the countries in the world government problem for paying close attention to deeply, if sludge of sewage treatment plants is not carried out harmless treatment, the sewage disposal that the input substantial contribution carries out is incomplete, even has lost meaning.The mud that sewage work produces has become big public hazards, cancellation mud is stacked field, landfill yard, can save a large amount of land resources, the secondary pollution of avoiding that mud is stacked, surrounding environment being caused in the landfill process, realize the harmless treatment of mud, the ultimate disposal of mud is strided forward to innoxious, resource utilization direction.

No matter sludge treatment is to make building materials, still burns, or utilizes it to produce organic fertilizer, at first be to reduce water content, first carries out the HSM sewage work of burning sludge Germany, and the maximum SNB sludge incineration factory (Holland) in Europe, all carries out sludge drying before the burning operation.

And sludge drying is estimated by heat energy loss.The sludge drying of 1 ton of water ratio 75% to water content 12%, is needed evaporation 738 premium on currency branches, and evaporates 1 kg of water power consumption, 0.72 degree, if every degree is electric by 1 yuan of calculating, only electric cost just can not be lower than: 727 liters * 0.72 degree * 1.00=531 unit.

It should be noted that and still adopt flame or the directly mummification of fluidized-bed (Italy uses turbodrier) that passed on from one to another before the centuries both at home and abroad so far, produce the stench dust that a large amount of height cause a disease, disable in the production.In developed countries such as Europe, the United States, the how careful sludge drying factory of safe design no matter, its dust explosion accident is continuous all the time, so European Union has formulated explosion gas equipment and operation standard (ATEX) in 1994, puts teeth in 1 day July in 2003 comprehensively.Therefore, academia is thought: traditional means is handled mud and has been had no outlet.So prophesy in the industry:, find that at no distant date a kind of possibility better, revolutionary technology is very little in the sludge drying field.

How finding a kind of not only economic, safe but also free of contamination method for sludge treatment, is the pursuit that sewage treatment industry is dreamed of.

The objective of the invention is to be to provide a kind of and utilize mud that city domestic sewage treatment plant produces and through behind the zeolite powder thorough mixing of modification, after making its water content be lower than below 30%, carry out drying and other treatment again or other comprehensive utilization method is handled, reach the purpose of not only economic, safety but also free of contamination sludge treatment.

A further object of the present invention is to provide a kind of mud that city domestic sewage treatment plant is produced to carry out harmless treatment, the approach of recycling.

Another object of the present invention is the technology that is to provide a kind of sludge drying.

Sludge drying technology of the present invention is achieved in that

1, sewage work is removed moisture content through nitrated mud with squeezing machine, make its water content about 70%.

2, zeolite powder is heated to 100 ℃～150 ℃, get rid of free-water and zeolite water in the zeolite powder, its water content is close to zero, and fully mixes while hot with through the mud after the squeezing, the ratio of mud and zeolite powder is 1: 0.5～1: 1 (weight ratio).Mixed sludge water content is absorbed by zeolite powder, and wherein the water transform more than 12% becomes crystal water or zeolite water and obtains water content less than 30% mixture.

Its mesolite is clinoptilolite, phillipsite or mordenite.

3, the mixture with mud and zeolite powder carries out drying after the squeezing balling-up, obtains water content and is lower than 5% sludge-drying.

4 or mixed mud directly made material of construction such as paving brick, cement filler etc.

5 or mixed mud directly is mixed with mixed organic fertilizer.

Zeolite of the present invention is by silica (SiO ₄) tetrahedron and alumina (AlO ₄) tetrahedron is arranged in the skeleton with cage shape according to certain rules, have a lot of holes of uniform size and passage, the tool vesicular structure, its porosity reaches 23%-50%, specific surface area is big, surface energy height, the negative charge that extremely strong capacity that has by its surface and aluminum-oxygen tetrahedron have, so its adsorptive power is powerful especially, can absorbs and exchange ammonium ion, heavy metal, ammonia nitrogen and other pollutent and moisture.

Advantage of the present invention and effect:

1, the invention solves a large amount of mud land occupation and the secondary pollution problem in treating processes that city domestic sewage treatment plant produces, the protection environment is had its meaning energetically.

2, containing ammonia nitrogen in the city domestic sewage is 35-60mg/L, colloidal solid shape ammonia nitrogen wherein and organism and ion state ammonium (NH ⁺ ₄) most of flocculated and be deposited in the mud, by stable being stored in the zeolite after the zeolite adsorption.Heavy metal in the mud also is fixed in the zeolite by the extremely strong ion exchanging function of zeolite, has avoided the pollution of above-mentioned pollutent to environment.

3, the invention solves in the sludge drying treating processes because of consuming a large amount of energy, the problem that processing cost is too high, its processing costs be conventional sludge drying processing costs 1/10th in addition less than 1/10th.

4, the invention solves the stench dust discharge that a large amount of height of producing in produce when sludge incineration is handled poisonous, obnoxious flavour and the production cause a disease, disable.

5, the zeolite powder of the present invention's use has extremely strong adsorptive power, is a kind of good reodorant, can eliminate the foul smell that mud produces.Mud after the processing is to make material of construction and the good starting material of organic fertilizer.The result of comprehensive utilization makes sewage disposal and sludge disposal reach zero release veritably, has fundamentally solved the secondary pollution that sewage disposal causes environment.

Embodiment 1

1000 kilograms of the zeolite powders of 1000 kilograms in mud of water content 70% and process heat modification fully mix back granulation oven dry, or are directly used in the production material of construction or produce mixed organic fertilizer.

Embodiment 2

500 kilograms of the zeolite powders of 1000 kilograms in mud of water content 70% and process heat modification fully mix back granulation oven dry, or are directly used in the production material of construction or produce mixed organic fertilizer.

Claims

1. the method for sludge treatment of a municipal sewage plant, it is characterized in that: raw material and weight percent are: the ratio of mud and zeolite powder is 1: 0.5～1: 1 (weight ratio)

Wherein sludge moisture content is about 70%, and zeolite powder is clinoptilolite, phillipsite or mordenite.

2. the method for sludge treatment of municipal sewage plant as claimed in claim 1, it is characterized in that: production technique is:

1. the municipal sewage plant is removed moisture content through nitrated mud with squeezing machine, make its water content about 70%;

2. zeolite powder is heated to 100 ℃～150 ℃ by drying machine, remove free crystal water and zeolite water in the zeolite powder, its water content is close to zero, and fully mixes through the mud after the squeezing while hot with 1., the ratio of mud and zeolite powder is 1: 0.5～1: 1 (weight ratio).Mixed sludge water content is absorbed by zeolite powder, and wherein the water transform more than 12% becomes crystal water or zeolite water and obtains water content less than 30% mixture;

3. 2. the mixture of gained carries out drying after the squeezing balling-up, makes its water content be lower than 5%;

4. will be 3. gained mixture or directly make material of construction such as paving brick, cement filler etc.;

5. will be 3. gained mixture or directly be mixed with mixed organic fertilizer.