CN200974802Y - Smoke gas residual heat and out-supplying heat combined sludge drying system - Google Patents

Abstract

The utility model discloses a sludge drying system combining the flu gas waste heat with external supply heat source, which comprises such subsystems as a heating system, a sludge pretreatment system, a feeding system, a sludge anhydration and particle formation system and a dust removal and degassing system, etc. through the two-segment anhydration process of the system, the water content of the sludge in sewage treatment plants is reduced, and the volume is reduced to less than one third of the original, which forms the sludge into a hard aggregate with a diameter of 0.5 millimeters-8 millimeters. The aggregate can be used as coal auxiliary fuel, which is also capable of being burned into light and energy saving bricks and cement pressed product. The utility model opens a new way of waste recycling utilization and treatment of a waste with another waste for the harmlessness, the quantitatively reduction and the resource recovery of the sludge in the sewage treatment plants, which makes the obvious social and environmental benefits produced and the remarkable economic benefits obtained.

Description

The sludge drying system that fume afterheat combines with outer supplying heat source

Technical field

The utility model relates to the sludge drying system that a kind of fume afterheat combines with outer supplying heat source.

Background technology

City domestic sewage and trade effluent must be through the processing of sewage work, could discharge after reaching state sewage emission standard, become a kind of enforceable environmental engineering measure.The responsibility of municipal sewage plant is purified waste water on the one hand, makes city domestic sewage and trade effluent qualified discharge after treatment; Be to dispose the mud that in sewage treatment process, produces safely on the other hand, prevent that mud from causing secondary environmental pollution.In recent decades, by constantly introducing and digesting advanced foreign technology, the water technology of China is reached its maturity, all kinds of sewage generally can both reach emission standard through after the purifying treatment.But, how to dispose and to handle enormous amount safely, and the water ratio height, and the mud of enrichment high density pollution thing and heavy metal, be the global problem that the municipal water treatment industry is faced.Developed country faces this difficult problem than us and takes Zao 20 years, although they are making huge effort in order to solve this difficult problem on the financial resources He on the manpower, substantially set up the mud sanitary landfill, the soil utilizes, burn and throw disposal treatment processs such as sea, but, it seems today these treatment processs not only technology itself have bigger defective, and implement and to bring bigger negative effect, particularly in China, the turnout of mud is very big, according to according to a preliminary estimate, the existing mud year output in the whole nation is above 100,000,000 tons, annual also with 1 15 speed increment, if adopt mud sanitary landfill method, and do not talk the mud transportation and the landfill expense very high, peri-urban is the space of suitable mud landfill not at all; If adopt the mud soil to utilize, being about to mud is developed to fertilizer and uses on agricultural, China's municipal sewage treatment adopts city domestic sewage and trade effluent to merge the method for handling more, therefore contain a large amount of heavy metals and persistence hazardous and noxious substances in the mud, even some mud is from sanitary sewage, although heavy metal content is lower, but the various medicaments that add in contained pathogenic agent and the sewage treatment process in the mud, harm is brought to environment in the capital, produce fertilizer with mud, on agricultural, use and to produce serious negative effect, hazardous and noxious substances in the mud and heavy metal can enrichments in soil, and enter food chain by the absorption of crop, finally are detrimental to health, be used for afforestation exactly, also can destroy ecotope because of build-up effect; Though burn and to make the obvious decrement of mud, but because the burning facility investment is big, energy-output ratio is big, therefore make the cost of sludge treatment per ton at least more than 400 yuan, and also processing once more of the residue after burning, according to the national conditions of China, this is difficult to bear economically, moreover, the caused Air Pollution Control of sludge incineration requires very high, is difficult to avoid producing dioxin in the particularly sludge incineration process, this technically also difficulty reach requirement; Mud is thrown the sea disposal and is also forbidded strictly by environmental protection department.As mentioned above, common in the world these method for sludge treatment that adopt, so far also do not have at home a kind ofly to be considered to effective treatment technology and can to use for reference, therefore, China's sludge from wastewater treatment plant is mainly taked the method for disposal that interim heap buries at present, this causes serious threat to ecotope, particularly ooze under the sewage in the mud, be unable to estimate especially to the harm that groundwater resource bring, and in fact peri-urban can not have space and the place that is fit to stack this class mud, the interim secondary environmental pollution problem of burying and producing of piling of mud is on the rise, the interim place of burying of piling of mud need be found as early as possible on the one hand because of the ever-increasing pressure of sludge quantity in some area; In a single day the interim heap of the mud resident that buries the place periphery recognizes the damaging influence of mud to living environment on the other hand, refusal mud heap buries, existing mud heap is buried the field, numerous and confused economic compensation to local government or enterprise's proposition great number, consequent contradiction is to become the social factors of instability.

Along with increasing rapidly of China's rapid economy development and urban population, the quantity of municipal effluent is constantly increasing, meanwhile people are also more and more higher to the requirement of environmental quality, trade effluent and domestic sewage treating rate also will improve constantly, the quantity that this means sludge of sewage treatment plant will grow with each passing day, therefore, it is very urgent to open up an effective sludge treatment approach.Current, both at home and abroad innoxious, minimizing and resource utilization as the ultimate aim that municipal sludge is thoroughly handled, practice also proof is only being carried out on the basis of minimizing mud, and then realizes innoxious and recycling treatment, could finally reach the target that mud is thoroughly handled; Practice shows that simultaneously the mud from sewage work produces passes through mechanical dehydration, water ratio is generally between 75%-85%, therefore have only at first promptly that safety realizes sludge drying again economically, make mud decrement after, could successfully carry out innoxious and recycling treatment to sludge of sewage treatment plant.Yet, pass through drying process, if the water ratio of mud is dropped to below 30%, can make the volume of mud reduce to water ratio is 80% below 1/3rd of sludge volume, but, this need consume a large amount of energy, makes that the cost of sludge drying is higher, thereby has limited the enforcement of sewage sludge harmlessness, minimizing and recycling treatment.In order to reduce the sludge drying processing cost significantly, the target of sewage sludge harmlessness and recycling treatment is achieved, we had once proposed to utilize the patent of invention technology of remaining heat of flue gas from steam power plant dewatered sludge, by setting up the tandem sludge drying system, the water ratio of mud is reduced to below 30%, sludge volume is reduced to below 1/3rd of original volume, mud after the mummification forms hard water-fast of quality naturally, preserved more than 90 percent of the original calorific value of mud simultaneously, become the intermediates of comprehensive utilization of mud, and the cost that makes sludge drying is reduced to minimum level, thereby overcome traditional sludge drying cost height, and be difficult to carry out sewage sludge harmlessness, the bottleneck problem of minimizing and recycling treatment has been opened up a recycling waste, the effective way of the treatment of wastes with processes of wastes against one another.The comprehensive assessment of this technology after the concrete enforcement in Jiangyin, Jiangsu shows, both realized the zero processing cost of sludge drying, the mud landfill takes and the sludge resource comprehensive utilization has produced tangible economic benefit because of saving again, thereby has obtained significant social, environment and economic triple benefit.

According to our understanding in depth, many places have the less fume afterheat resource of more scale, heat power plant's stack gas that these fume afterheat resources have from smaller power, the stack gas that has from various boiler emissions, owing to disperseing and measuring little, can not satisfy the mud energy needed requirement of mummification some amount, therefore difficulty is utilized.In order to make this part fume afterheat resource also can be used in sludge drying, when we have proposed dewatered sludge, on the basis that the fume afterheat resource that can utilize obtains utilizing fully, for the mud of wanting the mummification some amount and the insufficient energy, adopt and add the method that supplying heat source combines and remedy, thereby realize available fume afterheat resource is fully utilized, can satisfy the purpose of mummification some amount mud again.

Summary of the invention

The purpose of this utility model provides the sludge drying system that a kind of fume afterheat combines with outer supplying heat source.

It has the feeder that is connected, conveying belt, first opening for feed, the first revolution drying kiln, closed cold conveying belt, nicking formula pulverizer, belt-bucket elevator, second opening for feed, the second revolution drying kiln, screening plant, fluidizing furnace is through first ventilator trunk, the inlet mouth of second air door and the first revolution drying kiln joins, be provided with thermoswitch between the fluidizing furnace and second air door, first induced draft fan is through flue, the inlet mouth of first air door and the second revolution drying kiln joins, be provided with the 3rd air door between first ventilator trunk and the flue, the first revolution drying kiln, air outlet second ventilator trunk and the water dust scrubber of the second revolution drying kiln and closed cold conveying belt, second induced draft fan, flue dust joins.Feeder is connected with the mud that turns over the machine of mixing and stacks the field.

The first revolution drying kiln diameter is 1.8～2.4m, and length is 20～30m, and second revolution drying kiln diameter is 1.6～2.2m, and length is 18～28m.

The utlity model has following tangible advantage:

1) innoxious, the minimizing of sludge from wastewater treatment plant and recycling treatment are carried out under lower running cost, and make flue gas in the process of dewatered sludge, temperature reduces, through water dust scrubber, flue dust obtains more effective control, finally makes the discharging of flue gas reach national atmospheric emission standard;

2) energy dewatered sludge that utilizes fume afterheat and outer heat supply to combine, even one of them revolution drying kiln needs maintenance, another revolution drying kiln still can make the smooth and easy discharge of flue gas, therefore can not influence boiler normally moves, if because of fume afterheat can't utilize temporarily, outer supplying heat source can guarantee that still sludge treatment do not interrupt;

3) the utility model makes mud obtain mummification under cold condition, make mud keep 90% above primary calorific value on the one hand, mud granule after the mummification can be used as the auxiliary fuel of thermal power plant boiler fire coal, guaranteed that on the other hand the coagulating agent in the mud is not damaged, and made the quality hardness of mud granule satisfy the technical requirements of firing light energy saving brick and producing the cement pressed brick.Therefore, in fact this opened up a cyclic utilization of waste, and the effective way of the treatment of wastes with processes of wastes against one another can either produce significant social and environmental benefit, also can obtain tangible economic benefit.The utility model has dropped into practice on Jiangyin, Jiangsu and Changshu and other places, practice shows, not only make industry and sanitary sewage mud obtain effective innoxious and recycling treatment with this technology, and make fume afterheat resource qualified discharge fully when being fully utilized.

Description of drawings

Fig. 1 is the sludge drying system device structure synoptic diagram that fume afterheat combines with outer supplying heat source; Among the figure: feeder 1, conveying belt 2, first opening for feed 3, the first revolution drying kiln 4, closed cold conveying belt 5, nicking formula pulverizer 6, belt-bucket elevator 7, second opening for feed 8, the second revolution drying kiln 9, fluidizing furnace 10, thermoswitch 11, first ventilator trunk 12, second air door 13, the 3rd air door 14, first induced draft fan 15, flue 16, first air door 17, second ventilator trunk 18, water dust scrubber 19, second induced draft fan 20, flue dust 21, screening plant 22.

Fig. 2 is the sludge drying system mud preprocessing subsystem structural representation that fume afterheat combines with outer supplying heat source; Among the figure: mud is stacked field 23, is turned over the machine 24 that mixes.

Embodiment

As shown in Figure 1, 2, the sludge drying system that combines with outer supplying heat source of fume afterheat has subsystems such as heating system, mire preprocess system, feed system, sludge drying and granulating system, dedusting degasification.

Heating system has fluidizing furnace 10, thermoswitch 11, first vent-pipe 12, flue 16, first air door 17, second air door 13, the 3rd air door 14, first induced draft fan 15, the heat energy that fluidizing furnace 10 provides, by thermoswitch 11 temperature is controlled at 200～400 ℃, by second air door, 13 control hot blast rates, send into the first revolution drying kiln 4 by first ventilator trunk 12, send into the second revolution drying kiln 9 by the 3rd air door 14 control hot blast rates, first induced draft fan 15 is with the 100-250 ℃ of flue gas through fly-ash separator, by flue 16, send into the second revolution drying kiln 9 by first air door, 17 control exhaust gas volumns, by the 3rd air door 14 control exhaust gas volumns, send into the first revolution drying kiln 4.

Mire preprocess system has slot type heap mud field 23, piles at slot type to be provided with the machine 24 that mixes that turns on the mud field, and mud was stacked 2～5 days in slot type heap mud field 23, and mixed through turning over turning over of mixed machine 24, can spontaneous evaporation fall portion of water.

Feed system has feeder 1, conveying belt 2, and feeder 1 will be sent into first opening for feed 3 continuously equably through pretreated mud by conveying belt 2.

Sludge drying and granulating system have the first revolution drying kiln 4, the second revolution drying kiln 9, closed cooling conveyor 5, nicking formula pulverizer 6, belt-bucket elevator 7, screening plant 22, after first section mummification of mud through the first revolution drying kiln 4, by closed cooling conveyor 5, send into nicking formula pulverizer 6, mud agglomerate nicking that will be bigger is pulverized and is the mud granule of diameter 8～12mm, by belt-bucket elevator 7 this mud granule is sent into second opening for feed 8, form diameter after second section mummification of mud through the second revolution drying kiln 9 and be the scleroid mud granule below 8～10mm, through screening plant 22, diameter is that the mud granule of 2～6mm can be used as the raw material of firing the energy-saving light-weight brick and producing cement pressing products, and remaining mud granule can be used as coal-fired auxiliary fuel.

The dedusting gas-freeing system has second vent-pipe 18, water dust scrubber 19, second induced draft fan 20, chimney 21, second vent-pipe 18 will be received water dust scrubber 19 from the tail gas of the first revolution drying kiln 4, the second revolution drying kiln 9, closed cooling conveyor 5, to reach the tail gas of emission standard through the dedusting degasification by second induced draft fan 20, send into chimney 21.

Claims (3)

1. sludge drying system that fume afterheat combines with outer supplying heat source, it is characterized in that, it has the feeder (1) that is connected, conveying belt (2), first opening for feed (3), the first revolution drying kiln (4), closed cold conveying belt (5), nicking formula pulverizer (6), belt-bucket elevator (7), second opening for feed (8), the second revolution drying kiln (9), screening plant (22), fluidizing furnace (10) is through first ventilator trunk (12), second air door (13) joins with the inlet mouth of the first revolution drying kiln (4), be provided with thermoswitch (11) between fluidizing furnace (10) and second air door (13), first induced draft fan (15) is through flue (16), first air door (17) joins with the inlet mouth of the second revolution drying kiln (9), be provided with the 3rd air door (14) between first ventilator trunk (12) and the flue (16), the first revolution drying kiln (4), air outlet second ventilator trunk (18) and water dust scrubber (19) of the second revolution drying kiln (9) and closed cold conveying belt (5), second induced draft fan (20), flue dust (21) joins.

2. a kind of fume afterheat according to claim 1 and the sludge drying system that outer supplying heat source combines is characterized in that, described feeder (1) is connected with the mud that turns over mixed machine (24) and stacks (23).

3. the sludge drying system that a kind of fume afterheat according to claim 1 combines with outer supplying heat source, it is characterized in that the described first revolution drying kiln diameter is 1.8～2.4m, length is 20～30m, second revolution drying kiln diameter is 1.6～2.2m, and length is 18～28m.