Deep recovery system for flue gas waste heat of gas-fired boiler

Abstract

The utility model belongs to the technical field of gas-fired boiler heat energy recycling, and particularly relates to a gas-fired boiler flue gas waste heat deep recovery system. Comprising a gas-fired boiler, a sewage waste heat recovery device, a compression heat pump, a first flue gas waste heat exchange device and a second flue gas waste heat exchange device, a heat supply water supply pipe and a heat supply water return pipe are arranged at the bottom of the gas-fired boiler, the heat supply water supply pipe is connected with a heat supply terminal, and a water outlet of the heat supply water return pipe is connected with a water inlet of the compression heat pump; the compression heat pump is provided with a fourth return pipe, the fourth return pipe is connected with a return valve set arranged on the upper portion of the gas-fired boiler, a gas inlet of the second smoke waste heat exchange device is connected with a smoke outlet of the gas-fired boiler, and a smoke inlet of the first smoke waste heat exchange device is connected with a smoke outlet of the second smoke waste heat exchange device; and a water inlet of the sewage waste heat recovery device is connected with a sewage outlet of the gas-fired boiler. The flue gas waste heat deep recovery system is high in recovery efficiency.

Description

Technical Field

[0001] The utility model belongs to the technical field of heat recovery and utilization of gas boilers, and in particular relates to a gas boiler flue gas waste heat deep recovery system. Background Art

[0002] Currently, the wastewater generated by gas boilers is directly discharged or stored for treatment, which will cause high-temperature wastewater to pollute the environment; however, some existing treatment methods cannot achieve the effect of resource recycling, so they are urgently needed to be improved.

[0003] Therefore, we propose a gas boiler flue gas waste heat deep recovery system. Utility Model Content

[0004] In view of the above deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a gas boiler flue gas waste heat deep recovery system, which solves the problem of incomplete preheating of flue gas and preheating of sewage in the existing gas boiler.

[0005] In order to achieve the above objectives, the present invention adopts the following technical solutions:

[0006] A system for recovering flue gas waste heat from a gas-fired boiler comprises a gas-fired boiler, a sewage waste heat recovery device, a compression heat pump, a first flue gas waste heat exchange device and a second flue gas waste heat exchange device. A heating water supply pipe and a heating return water pipe are arranged at the bottom of the gas-fired boiler. The heating water supply pipe is connected to a heating terminal. The water outlet of the heating return water pipe is connected to the water inlet of the compression heat pump. A fourth return pipe is arranged on the compression heat pump. The fourth return pipe is connected to a return valve group arranged on the upper part of the gas-fired boiler. The air inlet of the second flue gas waste heat exchange device is connected to the smoke outlet of the gas-fired boiler. The smoke inlet of the first flue gas waste heat exchange device is connected to the smoke outlet of the second flue gas waste heat exchange device. The water inlet of the sewage waste heat recovery device is connected to the sewage outlet of the gas-fired boiler. A third heat recovery component is arranged in the sewage waste heat recovery device. The water inlet end of the third heat recovery component is connected to the compression heat pump through a first conduit. The water outlet end of the third heat recovery component is connected to the return valve group through a third return pipe.

[0007] Furthermore, a second heat recovery component is provided inside the first flue gas waste heat exchange device, the water inlet of the second heat recovery component is connected to the water outlet of the compression heat pump through a third conduit, and the water outlet of the second heat recovery component is connected to the reflux valve group through a first reflux pipe.

[0008] Furthermore, a first heat recovery component is provided inside the second flue gas waste heat exchange device, the water inlet of the first heat recovery component is connected to the water outlet of the compression heat pump through a second conduit, and the second return pipe of the water outlet of the first heat recovery component is connected to the return valve group.

[0009] Furthermore, a condensate drain pipe is provided at the bottom of the first flue gas waste heat exchange device and the second flue gas waste heat exchange device.

[0010] In summary, due to the adoption of the above technical solution, the beneficial technical effects of the utility model are:

[0011] A gas boiler flue gas waste heat deep recovery system, during operation, low-temperature water refluxed from the heating terminal flows back into the compression heat pump, and the low-temperature water is preheated by the compression heat pump and the sewage waste heat recovery device, and the preheated water enters the gas boiler through the reflux valve group, and the preheated water enters the gas boiler again to be heated. During the whole process, the starting temperature of the boiler heating is higher because the water entering the gas boiler is preheated, so the heating efficiency is significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is the front view of the utility model.

[0013] Figure 2 For this utility model Figure 1 Schematic diagram on the left.

[0014] Figure 3 For this utility model Figure 1 Top view of the .

[0015] Figure 4 It is a three-dimensional structural schematic diagram of the utility model.

[0016] In the figure: gas boiler 1, sewage waste heat recovery device 2, compression heat pump 3, first flue gas waste heat exchange device 4, second flue gas waste heat exchange device 5, return valve group 6, second heat recovery component 7, third heat recovery component 8, water inlet 9, heating and water supply pipe 10, first return pipe 11, second return pipe 12, third return pipe 13, fourth return pipe 14, first conduit 15, second conduit 16, third conduit 17, a heat recovery component 18. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail in combination with the embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model content, and are not used to limit the utility model content.

[0018] Example 1

[0019] In this embodiment, Figure 1-4As shown, a gas boiler flue gas waste heat deep recovery system includes a gas boiler 1, a sewage waste heat recovery device 2, a compression heat pump 3, a first flue gas waste heat exchange device 4 and a second flue gas waste heat exchange device 5. A heating water supply pipe 10 and a heating return water pipe are provided at the bottom of the gas boiler 1. The heating water supply pipe 10 is connected to the heating terminal. The water outlet of the heating return water pipe is connected to the water inlet 9 of the compression heat pump 3. The compression heat pump 3 is provided with a fourth return pipe 14. The fourth return pipe 14 is connected to the return valve group 6 provided on the upper part of the gas boiler 1. The air inlet of the second flue gas waste heat exchange device 5 is connected to the smoke outlet of the gas boiler 1, and the smoke inlet of the first flue gas waste heat exchange device 4 is connected to the smoke outlet of the second flue gas waste heat exchange device 5; the water inlet of the sewage waste heat recovery device 2 is connected to the sewage outlet of the gas boiler 1, and the sewage waste heat recovery device 2 is provided with a third heat recovery component 8, the water inlet end of the third heat recovery component 8 is connected to the compression heat pump 3 through the first conduit 15, and the water outlet end of the third heat recovery component 8 is connected to the return valve group 6 through the third return pipe 13. In the whole recovery process, the low-temperature water refluxed from the heating terminal flows back to the compression heat pump 3, and the low-temperature water is preheated by the compression heat pump 3 and the sewage waste heat recovery device 2. The preheated water enters the gas boiler 1 through the return valve group 6, and the preheated water enters the gas boiler 1 to be heated. In the whole process, the water entering the gas boiler 1 is preheated, so that the starting temperature of the heating is high, resulting in a significant improvement in the heating efficiency. A second heat recovery component 7 is provided inside the first flue gas waste heat exchange device 4, and the water inlet of the second heat recovery component 7 is connected to the water outlet of the compression heat pump 3 through the third conduit 17, and the water outlet of the second heat recovery component 7 is connected to the reflux valve group 6 through the first reflux pipe 11. A first heat recovery component 18 is provided inside the second flue gas waste heat exchange device 5, and the water inlet of the first heat recovery component 18 is connected to the water outlet of the compression heat pump 3 through the second conduit 16, and the water outlet second reflux pipe 12 of the first heat recovery component 18 is connected to the reflux valve group 6. Condensate drainage pipes are provided at the bottom of the first flue gas waste heat exchange device 4 and the second flue gas waste heat exchange device 5.

[0020] After the flue gas from the gas boiler 1 passes through the first flue gas waste heat exchange device 4 and the second flue gas waste heat exchange device 5, the temperature of the flue gas is greatly reduced and then discharged; the low-temperature water refluxed from the heating terminal passes through the first flue gas waste heat exchange device 4 and the second flue gas waste heat exchange device 5, absorbs the pre-waste heat of the discharged flue gas, and is finally transported to the gas boiler 1 through the reflux valve group 6. During the reflux process, the water entering the gas boiler 1 is preheated, so that the starting temperature of the heating is relatively high, resulting in a significant improvement in the heating efficiency.

[0021] The above description is a preferred embodiment of the utility model content and is not intended to limit the utility model content. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the utility model content should be included in the protection scope of the utility model content.

Claims

1. A gas boiler flue gas waste heat deep recovery system, comprising a gas boiler (1), a sewage waste heat recovery device (2), a compression heat pump (3), a first flue gas waste heat exchange device (4) and a second flue gas waste heat exchange device (5), characterized in that: A heating water supply pipe (10) and a heating water return pipe are provided at the bottom of the gas boiler (1). The heating water supply pipe (10) is connected to the heating terminal. The water outlet of the heating water return pipe is connected to the water inlet (9) of the compression heat pump (3). The compression heat pump (3) is provided with a fourth return pipe (14). The fourth return pipe (14) is connected to a return valve group (6) provided on the upper part of the gas boiler (1). The air inlet of the second flue gas waste heat exchange device (5) is connected to the smoke outlet of the gas boiler (1). The smoke inlet of the first flue gas waste heat exchange device (4) is connected to the sewage outlet of the second flue gas waste heat exchange device (5). A third heat recovery component (8) is provided in the sewage waste heat recovery device (2). The water inlet end of the third heat recovery component (8) is connected to the compression heat pump (3) through a first conduit (15). The water outlet end of the third heat recovery component (8) is connected to the return valve group (6) through a third return pipe (13).

2. A gas boiler flue gas waste heat deep recovery system according to claim 1, characterized in that: A second heat recovery component (7) is provided inside the first flue gas waste heat exchange device (4); a water inlet of the second heat recovery component (7) is connected to a water outlet of the compression heat pump (3) via a third conduit (17); and a water outlet of the second heat recovery component (7) is connected to a reflux valve assembly (6) via a first reflux pipe (11).

3. A gas boiler flue gas waste heat deep recovery system according to claim 1, characterized in that: A first heat recovery component (18) is provided inside the second flue gas waste heat exchange device (5); a water inlet of the first heat recovery component (18) is connected to a water outlet of the compression heat pump (3) via a second conduit (16); and a second return pipe (12) at the water outlet of the first heat recovery component (18) is connected to a return valve group (6).

4. A gas boiler flue gas waste heat deep recovery system according to claim 1, characterized in that: Condensate drain pipes are provided at the bottom of the first flue gas waste heat exchange device (4) and the second flue gas waste heat exchange device (5).

Images