阅读说明：本技术 一种低品位工业废气余热回收利用系统 (Low-grade industrial waste gas waste heat recovery utilizes system ) 是由 于大杰 于 2021-08-25 设计创作，主要内容包括：本发明涉及一种低品位工业废气余热回收利用系统,包括烘房、进气口与排气口,所述排气口通过管道依次与漆雾过滤器、余热回收换热器、VOCs吸附床、空气源热泵机组、排风机、排放烟囱相连,所述VOCs吸附床上设有VOCs脱附通道,所述VOCs脱附通道上依次循环连接有VOCs吸附床、脱附风机、RCO炉、阻火器、换向阀,所述换向阀上还连接有补冷风机以及脱附旁通通道,所述空气源热泵机组上设有与前处理室相连的供水管与回水管,所述供水管或回水管上还设有循环水泵,所述前处理室内设有分别与所述供水管、回水管相连的槽液加热器。本发明有效去除了涂装工艺产生的有机废气,既减少了污染物的排放,又将尾气余热回收利用,使经济效益、环境效益得到良好结合。(The invention relates to a low-grade industrial waste gas waste heat recycling system which comprises a drying room, an air inlet and an air outlet, wherein the air outlet is sequentially connected with a paint mist filter, a waste heat recycling heat exchanger, a VOCs adsorption bed, an air source heat pump unit, an exhaust fan and a discharge chimney through pipelines, a VOCs desorption channel is arranged on the VOCs adsorption bed, the VOCs desorption channel is sequentially and circularly connected with the VOCs adsorption bed, a desorption fan, an RCO furnace, a flame arrester and a reversing valve, a cooling supplementing fan and a desorption bypass channel are further connected on the reversing valve, a water supply pipe and a water return pipe which are connected with a pretreatment chamber are arranged on the air source heat pump unit, a circulating water pump is further arranged on the water supply pipe or the water return pipe, and a tank liquid heater which is respectively connected with the water supply pipe and the water return pipe is arranged in the pretreatment chamber. The invention effectively removes the organic waste gas generated by the coating process, reduces the emission of pollutants, and recycles the waste heat of the tail gas, thereby well combining economic benefit and environmental benefit.)

1. The utility model provides a low-grade industrial waste gas waste heat recovery utilizes system, includes baking house (1), be equipped with air inlet and gas vent on baking house (1), its characterized in that: the exhaust port is connected with a paint mist filter (2), a waste heat recovery heat exchanger (4), a VOCs adsorption bed (17), an air source heat pump unit (5), an exhaust fan (11) and a discharge chimney (12) in sequence through pipelines, a VOCs desorption channel is arranged on the VOCs adsorption bed (17), a desorption fan (8), an RCO furnace (3), a fire arrester (9) and a reversing valve (18) are sequentially and circularly connected on the VOCs desorption channel, a supplementary air cooler (10) and a desorption bypass channel (21) are further connected on the reversing valve (18), a water supply pipe (19) and a water return pipe (20) which are connected with a pretreatment chamber (13) are arranged on the air source heat pump unit (5), a circulating water pump (6) is further arranged on the water supply pipe (19) or the water return pipe (20), and a water supply pipe (19), The tank liquid heater (14) is connected with the water return pipe (20), and tank liquid (15) is filled in the tank liquid heater (14);

two mutually isolated smoke exhaust channels and a fresh air channel are arranged in the waste heat recovery heat exchanger (4), the inlet and the outlet of each smoke exhaust channel are respectively communicated with the outlet of the paint mist filter (2) and the inlet of the VOCs adsorption bed (17), the outlet of each fresh air channel is communicated with the air inlet of the drying room (1), the inlet and the outlet temperatures of the fresh air channels are respectively 30 ℃ and 70 ℃, and the inlet and the outlet temperatures of the smoke exhaust channels are respectively 90 ℃ and 40 ℃;

the RCO furnace (3) is internally provided with a natural gas combustion unit, heat storage ceramics and a temperature sensor, and when the temperature sensor monitors that the temperature in the RCO furnace (3) is lower than a target temperature, the control unit automatically starts the natural gas combustion unit in the RCO furnace (3) to heat the heat storage ceramics.

2. The waste heat recovery system according to claim 1, wherein: the fresh air channel is also provided with an electric valve (16) and a fresh air supplementing machine (7).

3. The waste heat recovery system according to claim 1, wherein: the evaporator of the air source heat pump unit (5) is arranged in the smoke exhaust channel, and the condenser of the air source heat pump unit (5) is communicated with the water return pipe (20) for heat exchange.

Technical Field

The invention relates to a waste heat recycling system, in particular to a low-grade industrial waste gas waste heat recycling system.

Background

At present, a large amount of large air quantity and low-medium concentration exhaust emission can be generated in the production process of industries such as automobile parts, new energy automobiles, whole automobiles, electric automobiles, mechanical paint spraying, coating and coating, aluminum coating and the like. With the advanced promotion of the national environmental protection, the requirements for the emission of the waste gas are more and more strict, and the waste gas still contains a large amount of residual heat, so that the direct emission also causes energy waste and can be utilized.

Drying rooms are generally available in the coating industry. In the automotive coating process, for example, baking at relatively high temperatures is required in order to dry the paint sprayed on the vehicle body. The baking process is carried out in a closed baking room, the temperature of the baking room is controlled to be 140-160 ℃, on one hand, external fresh air needs to be supplemented in the baking process, so that air in the baking room flows, the effective utilization of heat energy is promoted, and on the other hand, partial air needs to be discharged outwards from the baking room to achieve air volume balance. Since VOCs (volatile organic compounds) are generated in the baking process, air pollution is caused by direct discharge, and waste gas and waste heat cannot be effectively utilized.

Therefore, there is a need to develop a waste heat recovery system to treat exhaust gas with the system, so as to reduce air pollution, and simultaneously perform waste heat recovery to reduce heat waste.

Disclosure of Invention

The invention aims to provide a low-grade industrial waste gas waste heat recycling system aiming at the current situations of tail gas pollution and heat waste in the current coating industry, so that the system is utilized to treat tail gas, atmospheric pollution is reduced, waste heat is recycled, and heat waste is reduced.

In order to achieve the aim, the invention provides a low-grade industrial waste gas waste heat recycling system, which comprises a drying room, the drying room is provided with an air inlet and an air outlet, the air outlet is sequentially connected with the paint mist filter, the waste heat recovery heat exchanger, the VOCs adsorption bed, the air source heat pump unit, the exhaust fan and the exhaust chimney through pipelines, the VOCs adsorption bed is provided with a VOCs desorption channel, the VOCs desorption channel is sequentially and circularly connected with the VOCs adsorption bed, a desorption fan, an RCO furnace, a flame arrester and a reversing valve, the reversing valve is also connected with a supplementary cooling fan and a desorption bypass channel, the air source heat pump unit is provided with a water supply pipe and a water return pipe which are connected with the pretreatment chamber, a circulating water pump is further arranged on the water supply pipe or the water return pipe, a tank liquor heater connected with the water supply pipe and the water return pipe respectively is arranged in the pretreatment chamber, and tank liquor is filled in the tank liquor heater;

the waste heat recovery heat exchanger is internally provided with two mutually isolated smoke exhaust channels and a fresh air channel, an inlet and an outlet of each smoke exhaust channel are respectively communicated with an outlet of the paint mist filter and an inlet of the VOCs adsorption bed, an outlet of the fresh air channel is communicated with an air inlet of the drying room, the inlet and the outlet of the fresh air channel are respectively at 30 ℃ and 70 ℃, and the inlet and the outlet of each smoke exhaust channel are respectively at 90 ℃ and 40 ℃;

the RCO furnace is internally provided with a natural gas combustion unit, heat storage ceramics and a temperature sensor, and when the temperature sensor monitors that the temperature in the RCO furnace is lower than a target temperature, the control unit automatically starts the natural gas combustion unit in the RCO furnace to heat the heat storage ceramics.

Preferably, the fresh air channel is further provided with an electric valve and a fresh air supplementing machine.

Preferably, the air source heat pump unit evaporator is arranged in the smoke exhaust channel, and the air source heat pump unit condenser is communicated with the water return pipe for heat exchange.

Based on the technical scheme, the invention has the advantages that:

the low-grade industrial waste gas waste heat recycling system constructs heat energy system circulation of 'drying room (organic waste gas) -RCO furnace (heat energy) -drying room-air source heat pump unit', reduces the natural gas consumption of heating equipment by 8% under the action of the RCO furnace, a heat exchanger and an air source heat pump, and improves the heating efficiency of the air source heat pump by 40%.

The invention effectively removes the organic waste gas generated by the coating process, reduces the emission of pollutants, reduces the influence of the production process of enterprises on the environment, recycles the waste heat of the tail gas, realizes greater economic benefit and well combines the economic benefit and the environmental benefit.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:

fig. 1 is a schematic diagram of a low-grade industrial waste gas waste heat recycling system.

Detailed Description

The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.

The invention provides a low-grade industrial waste gas waste heat recycling system, which is shown in figure 1, wherein a preferred embodiment of the invention is shown.

Specifically, the low-grade industrial waste gas waste heat recycling system comprises a drying room 1, wherein an air inlet and an air outlet are arranged on the drying room 1, the air outlet is sequentially connected with a paint mist filter 2, a waste heat recycling heat exchanger 4, a VOCs adsorption bed 17, an air source heat pump unit 5, an exhaust fan 11 and a discharge chimney 12 through pipelines, a VOCs desorption channel is arranged on the VOCs adsorption bed 17, the VOCs desorption channel is sequentially and circularly connected with the VOCs adsorption bed 17, a desorption fan 8, an RCO furnace 3, a flame arrester 9 and a reversing valve 18, the reversing valve 18 is further connected with a supplementary cooling fan 10 and a desorption bypass channel 21, the air source heat pump unit 5 is provided with a water supply pipe 19 and a water return pipe 20 which are connected with a pretreatment chamber 13, the water supply pipe 19 or the water return pipe 20 is further provided with a circulating water pump 6, and a tank liquid heater 14 which is respectively connected with the water supply pipe 19 and the water return pipe 20 is arranged in the pretreatment chamber 13, the tank liquid heater 14 is filled with tank liquid 15.

Two mutually isolated smoke exhaust channels and a fresh air channel are arranged in the waste heat recovery heat exchanger 4, the inlet and the outlet of each smoke exhaust channel are respectively communicated with the outlet of the paint mist filter 2 and the inlet of the VOCs adsorption bed 17, the outlet of the fresh air channel is communicated with the air inlet of the drying room 1, the inlet and the outlet temperatures of the fresh air channel are respectively 30 ℃ and 70 ℃, and the inlet and the outlet temperatures of the smoke exhaust channels are respectively 90 ℃ and 40 ℃.

The RCO furnace 3 is internally provided with a natural gas combustion unit, heat storage ceramics and a temperature sensor, and when the temperature sensor monitors that the temperature in the RCO furnace 3 is lower than a target temperature, the control unit automatically starts the natural gas combustion unit in the RCO furnace 3 to heat the heat storage ceramics.

As shown in fig. 1, the fresh air channel is further provided with an electric valve 16 and a fresh air supply fan 7 for heating the fresh air by using the waste heat in the waste heat recovery heat exchanger 4, and the fresh air is sent into the drying room 1. Preferably, the evaporator of the air source heat pump unit 5 is arranged in the smoke exhaust channel, the condenser of the air source heat pump unit 5 is communicated with the water return pipe 20 for heat exchange, and the waste heat in the smoke exhaust is reused for heating the bath heater 14 and heating the inside of the treatment chamber 13.

Because VOCs (volatile organic compounds) can be generated in the baking process, air pollution can be caused by direct discharge, and simultaneously waste gas and waste heat can not be effectively utilized, the invention increases an RCO furnace 3 (a regenerative catalytic oxidation combustion furnace) and an air source heat pump unit to treat and coat organic waste gas and recover the waste heat.

As shown in FIG. 1, the exhaust gas from the drying room 1 is treated by the RCO furnace 3 and then discharged and reused. The RCO furnace can carry out low temperature oxidation treatment to the organic waste gas that baking house 1 produced, and the leading-in RCO furnace 3 of 1 exhaust gas vent of baking house can reach the purpose, and the inside temperature of RCO furnace 3 can reach 250 ~ 300 ℃, through the balance to the waste gas volume, sets up reasonable waste gas dwell time, can effectively get rid of organic waste gas.

The RCO furnace 3 is started and maintained by using natural gas, a natural gas combustion unit, heat storage ceramic and a temperature sensor are arranged in the RCO furnace 3, heat energy generated in the combustion process of VOCs can be stored, and consumption of the natural gas is reduced. When the temperature sensor monitors that the temperature in the RCO furnace 3 is lower than the target temperature, the control unit automatically starts the natural gas combustion unit in the RCO furnace 3 to heat the heat storage ceramic. Meanwhile, the temperature of a gas inlet and a gas outlet in the RCO furnace 3 and the temperature in the furnace are collected, the temperature of the gas inlet is 40 ℃, the temperature of the gas in the furnace is 298 ℃, and the temperature of the gas outlet still reaches about 60 ℃, so that the heat energy can be recycled by additionally arranging a heat exchanger.

And the flue gas waste heat can be recovered due to the higher temperature of the flue gas discharged by the RCO furnace 3. Therefore, a reversing valve 18 is additionally arranged behind the RCO furnace 3, the flue gas discharged from the RCO furnace 3 is mixed with the fresh air to be fed into the VOCs adsorption bed, and the desorption temperature of the VOCs is adjusted. After adding VOCs adsorption bed 17, purify baking house 1 exhaust waste gas, this part purifies back gas still contains the heat, can also make full use of on the air source heat pump set. The purified waste gas is stable in quantity and temperature, and is used on the air source heat pump unit 5, so that the heat exchange efficiency of the fin heat exchanger on the air source heat pump is guaranteed, and the fins are prevented from frosting. Compared with the running process of an air source heat pump system with frosting and defrosting, the efficiency can be improved by 40 percent, the economic cost is reduced greatly, and the air source heat pump system is an ideal air source.

Since the workpiece before coating needs hot water washing in the pretreatment line, hot water needs to be supplied to the bath solution for heating in the pre-degreasing, degreasing and phosphating processes. The air source heat pump unit 5 can prepare hot water of 90 ℃ to meet the temperature of a tank liquid treatment workpiece, a water supply pipe 19 and a water return pipe 20 on the air source heat pump unit 5 are connected to a water inlet and a water outlet of a heater 14 in a liquid tank, a circulating water pump 6 is further arranged on the water supply pipe 19 or the water return pipe 20, a tank liquid heater 14 connected with the water supply pipe 19 and the water return pipe 20 is arranged in the pretreatment chamber 13, and tank liquid 15 is filled in the tank liquid heater 14; when the air source heat pump unit 5 operates, the circulating water pump 6 operates, hot water circulates in the pipeline, and the tank liquor is heated to the required temperature, so that the consumption of hot gas by using a boiler is saved, the environment is protected, and the operating cost is saved.

The low-grade industrial waste gas waste heat recycling system constructs heat energy system circulation of 'drying room (organic waste gas) -RCO furnace (heat energy) -drying room-air source heat pump unit', reduces the natural gas consumption of heating equipment by 8% under the action of the RCO furnace, a heat exchanger and an air source heat pump, and improves the heating efficiency of the air source heat pump by 40% in winter.

The invention effectively removes the organic waste gas generated by the coating process, reduces the emission of pollutants, reduces the influence of the production process of enterprises on the environment, recycles the waste heat of the tail gas, realizes greater economic benefit and well combines the economic benefit and the environmental benefit.

Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present invention and not to limit the same; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art will understand that: modifications to the specific embodiments of the invention or equivalent substitutions for parts of the technical features may be made; without departing from the spirit of the present invention, it is intended to cover all aspects of the invention as defined by the appended claims.