System for recovering waste heat of sludge heat drying dead steam

Abstract

The utility model provides a system for recovering waste heat of sludge heat drying dead steam, which comprises a drying machine, the dead steam end of the drying machine is connected with a spray washing tower through an electric valve group, the dead steam heat of the spray washing tower is connected with a heat exchanger through a pipeline, the upper end of the heat exchanger is provided with a heat exchange medium inlet, and the lower end of the heat exchanger is provided with a heat exchange medium outlet. A heat exchange medium outlet is formed in the lower end of the heat exchanger. The waste steam heat energy recycling device has the advantages that waste steam heat energy generated by sludge heat drying can be recycled, waste heat of waste steam is effectively utilized to reduce consumption of circulating water, sludge treatment cost is reduced, and practicability is high.

Description

Technical Field

[0001] The utility model belongs to the technical field of heat energy recovery and treatment, and in particular relates to a system for recovering waste heat of exhaust steam from sludge thermal drying. Background Art

[0002] The sludge discharged from urban sewage treatment plants has a moisture content of about 80% after gravity concentration and mechanical dehydration. It is large in size and has a low calorific value. It is not suitable for aerobic composting, incineration, building material utilization, or even landfill. It must be further dehydrated and dried. After the sludge is concentrated, physical methods are used to further reduce the moisture content of the sludge to facilitate the transportation, accumulation, utilization or further treatment of the sludge. There are two types of dehydration (drying): natural evaporation and mechanical dehydration. It is customary to call mechanical dehydration sludge dehydration and natural evaporation sludge drying. Sludge drying is the premise and key to sludge treatment and disposal technology. The sludge drying process equipment that is currently used more frequently includes fluidized bed drying, belt drying, paddle drying, horizontal rotary drying, vertical disc drying and other process equipment. The exhaust steam generated during the drying process will be processed by the dust collector and condenser, the condensed wastewater will be sent to the wastewater treatment system, and the exhaust steam will be sent to the waste gas treatment system or sent to the boiler to be burned as the primary and secondary air of the boiler. At present, the exhaust steam generated by the dryer is directly cooled by circulating water, and its heat cannot be effectively utilized, which easily causes energy waste; the overall sludge drying cost is high. How to reduce the cost of sludge treatment has become one of the technical problems that need to be solved at present. Utility Model Content

[0003] In order to solve the deficiencies of the prior art and reduce energy consumption, the utility model provides a system for recovering waste heat from exhaust steam of sludge thermal drying.

[0004] The purpose of the utility model is achieved through the following technical solutions:

[0005] A system for recovering waste heat from exhaust steam from sludge thermal drying comprises a dryer, the exhaust steam end of the dryer is connected to a spray washing tower via an electric valve group, the exhaust steam heat of the spray washing tower is connected to a heat exchanger via a pipeline, a heat exchange medium inlet is provided at the upper end of the heat exchanger, and a heat exchange medium outlet is provided at the lower end of the heat exchanger.

[0006] Preferably, one end of the spray scrubbing tower is connected to a steam-water separator via a vacuum pump, the gas end of the steam-water separator is connected to a waste gas treatment system, and the wastewater end of the steam-water separator is connected to a wastewater treatment system.

[0007] Preferably, a wastewater outlet is provided at the bottom of the spray washing tower, and the wastewater outlet is connected to a wastewater treatment system.

[0008] Preferably, an integrated dust collector is connected to the upper end of the dryer, and the integrated dust collector is connected to the spray washing tower through the electric valve group.

[0009] Preferably, a mud outlet is provided at the lower end of the dryer, and a double-flap air lock is provided at the mud outlet. A mud inlet is provided at the upper end of the dryer, and the mud inlet and the mud outlet are respectively provided at two ends of the dryer.

[0010] Preferably, the exhaust steam heat of the spray scrubber enters the heat exchanger through a pipeline and a circulating water pump for heat exchange and then enters the spray scrubber again for spray circulation.

[0011] The beneficial effects of the utility model are embodied in that the utility model can recycle the exhaust steam heat energy generated by sludge thermal drying, effectively utilize the waste heat of the exhaust steam to reduce the consumption of circulating water, reduce the sludge disposal cost, and has strong practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0013] Figure 1 : Schematic diagram of system connection structure of the utility model. DETAILED DESCRIPTION

[0014] The utility model discloses a system for recovering waste heat from exhaust steam from sludge thermal drying. Figure 1 As shown, it includes a dryer 1, and the dryer can be a disc, thin layer, paddle or other dryer. The two ends of the dryer are respectively provided with a steam inlet 13 and a steam outlet 14, and the steam enters through the steam inlet to provide heat to the inside of the dryer. The upper and lower ends of the dryer 1 are respectively provided with a mud inlet 11 and a mud outlet 12, and the mud inlet 11 and the mud outlet 12 are respectively provided at the two ends of the dryer. The mud outlet 12 is further provided with a double-flap air lock, which prevents the exhaust gas in the dryer from leaking, is beneficial to environmental protection, and is not easy to cause pollution.

[0015] The upper end of the dryer 1 is connected to an integrated dust collector 2, which performs dust removal once. The integrated dust collector 2 is connected to the spray washing tower 4 through the electric valve group 3. The exhaust steam heat of the spray washing tower 4 is connected to the heat exchanger 5 through a pipeline. The upper end of the heat exchanger 5 is provided with a heat exchange medium inlet 51, and the lower end of the heat exchanger 5 is provided with a heat exchange medium outlet 52. Furthermore, the exhaust steam heat of the spray washing tower 4 enters the heat exchanger through a pipeline through a circulating water pump 45 for heat exchange and then enters the spray washing tower 4 again for spray circulation. A wastewater outlet 41 is provided at the bottom of the spray washing tower 4, and the wastewater outlet 41 is connected to the wastewater treatment system.

[0016] One end of the spray scrubber 4 is connected to a steam-water separator 7 through a vacuum pump 6. The steam-water separator 7 performs secondary cooling on the exhaust steam and removes water mist. The treated exhaust steam enters the waste gas treatment system through the gas end for treatment, or is sent to the boiler for incineration as the primary and secondary air of the boiler. The wastewater end of the steam-water separator 7 is connected to the wastewater treatment system.

[0017] In this system, the sludge dried by the dryer is transported separately or disposed of in coordination through the mud outlet. The exhaust steam generated by the dried sludge will first enter the integrated dust collector for primary dust removal. The exhaust steam after dust removal is adjusted by the electric valve group 3 to enter the spray scrubber. The exhaust steam entering the spray scrubber is sprayed and cooled, and the vacuum pump maintains the system negative pressure and passes through the steam-water separator for secondary dust removal, cooling and water mist removal before being sent to the exhaust gas treatment system. The exhaust steam heat absorbed by the spray scrubber is sent to the heat exchanger through the circulating water pump for heat exchange, and the heat exchange medium entering the heat exchanger is heated for waste heat recovery.

[0018] The system of the utility model can effectively recycle the heat energy of the exhaust steam generated by the thermal drying of sludge, effectively utilize the waste heat of the exhaust gas, and reduce the consumption of circulating water, thereby reducing the steam consumption of the thermal drying of sludge and also reducing the cost of sludge disposal.

[0019] Finally, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0020] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A system for recovering waste heat from sludge thermal drying, characterized by: It includes a dryer, the exhaust steam end of the dryer is connected to a spray washing tower through an electric valve group, the exhaust steam heat of the spray washing tower is connected to a heat exchanger through a pipeline, a heat exchange medium inlet is arranged at the upper end of the heat exchanger, and a heat exchange medium outlet is arranged at the lower end of the heat exchanger.

2. The system for recovering waste heat from sludge thermal drying as claimed in claim 1, characterized in that: One end of the spray washing tower is connected to a steam-water separator through a vacuum pump, a gas end of the steam-water separator is connected to a waste gas treatment system, and a waste water end of the steam-water separator is connected to a waste water treatment system.

3. The system for recovering waste heat from sludge thermal drying as claimed in claim 2, characterized in that: A wastewater outlet is provided at the bottom of the spray washing tower, and the wastewater outlet is connected to a wastewater treatment system.

4. The system for recovering waste heat from sludge thermal drying as claimed in claim 3, characterized in that: An integrated dust collector is connected to the upper end of the drying machine, and the integrated dust collector is connected to the spray washing tower through the electric valve group.

5. The system for recovering waste heat from sludge thermal drying as claimed in claim 4, characterized in that: The lower end of the dryer is provided with a mud outlet, and the mud outlet is provided with a double-flap air lock. The upper end of the dryer is provided with a mud inlet, and the mud inlet and the mud outlet are respectively provided at two ends of the dryer.

6. The system for recovering waste heat from sludge thermal drying as claimed in claim 5, characterized in that: The exhaust steam heat of the spray scrubber enters the heat exchanger through a pipeline and a circulating water pump for heat exchange, and then enters the spray scrubber again for spray circulation.

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