System for preventing dividing wall type flue gas heat exchanger from generating condensate water

Abstract

The utility model provides a system for preventing a dividing wall type flue gas heat exchanger from generating condensate water. The system comprises a heat supply network water outlet valve, a dividing wall type heat exchanger, a heat supply network water inlet valve and a circulating pump, the heat supply network water outlet valve is arranged on the outer side of a water outlet of the dividing wall type heat exchanger, the heat supply network water inlet valve is arranged on the outer side of a water inlet of the dividing wall type heat exchanger, and a water inlet of the circulating pump is connected between the water outlet of the dividing wall type heat exchanger and the heat supply network water outlet valve through a pipeline. And a water outlet of the circulating pump is connected between a water inlet of the dividing wall type heat exchanger and the heat supply network water inlet valve through a pipeline, so that at least one part of hot water subjected to heat exchange flows back to the water inlet of the dividing wall type heat exchanger through the circulating pump. The temperature of heat supply network water entering the dividing wall type heat exchanger is increased in a water mixing mode, the temperature of the water inlet can be increased to be above the dew point temperature of smoke, and the problem of condensate water is solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of partition wall type flue gas heat exchanger, especially to a system for preventing condensate water from being produced in the partition wall type flue gas heat exchanger. BACKGROUND

[0002] At present, many natural gas boilers for heating are equipped with partition wall type flue gas heat exchangers at the flue gas outlet, in which the flue gas at the outlet of the boiler is directly exchanged with the low-temperature heat network return water for fully utilizing the heat of the flue gas at a relatively high temperature and improving the energy utilization rate. The structural forms mainly include the tube fin type, the fully welded plate type, the brazing type, etc. The flue gas and the hot water flow in opposite directions, and the flue gas at about 200 DEG C can be reduced to below 100 DEG C. There is a large amount of water vapor in the flue gas produced by the combustion of natural gas, and the volume fraction is about 17%, and the dew point temperature is about 57 DEG C to 58 DEG C. When the inlet temperature of the hot water is lower than the dew point temperature, condensate water will inevitably be produced in the local position. The harm is that the condensate water is acidic with a PH value of about 3 to 4 due to the nitrogen oxides and carbon dioxide in the flue gas, which can corrode the partition wall type heat exchanger and affect the service life of the partition wall type heat exchanger. In addition, the gap between the plates of the partition wall type heat exchanger with the brazing or fully welded structure is small, and when the condensate water is produced, the resistance of the flue gas side will be greatly increased, which will affect the output of the burner and even open the explosion-proof door.

[0003] In order to solve the corrosion problem of the condensate water of the partition wall type flue gas heat exchanger on the heat exchanger, the current conventional method is to use corrosion-resistant materials such as stainless steel and ND steel and to set a condensate water discharge pipe at the bottom of the heat exchanger to discharge the condensate water in time or to reduce the flow of the hot water and to increase the outlet temperature of the flue gas. However, even if these measures are taken, when the hot water temperature is lower than the dew point temperature in the flue gas, the condensate water will inevitably be produced on the heat exchange surface at the local position of the hot water inlet, the gap of the weld of the heat exchange surface at the position where the condensate water is produced will be formed, the electrochemical corrosion will be caused, the corrosion and leakage from the outside to the inside of the heat exchange surface will be caused, and the safe and stable operation and the service life of the equipment will be affected. Therefore, how to avoid the occurrence of the condensate water in the partition wall type flue gas heat exchanger becomes a technical problem to be solved in the field. CONTENT OF THE UTILITY MODEL

[0004] The utility model discloses a system for preventing condensate water from being produced in the partition wall type flue gas heat exchanger.

[0005] The utility model provides a system for preventing condensate water from being produced by the wall type flue gas heat exchanger, including the heat network water export valve, the wall type heat exchanger, the heat network water import valve and the circulating pump, the heat network water export valve sets up the outside of wall type heat exchanger water outlet, the heat network water import valve sets up the outside of wall type heat exchanger water inlet, the water inlet of circulating pump is connected between the water outlet of wall type heat exchanger and heat network water export valve through the pipeline, the water outlet of circulating pump is connected between the water inlet of wall type heat exchanger and heat network water import valve through the pipeline, so that at least a part of the hot water after heat exchange is backflowed to the water inlet of wall type heat exchanger through circulating pump.

[0006] Further, a check valve is installed on the water outlet pipeline of the circulating pump.

[0007] Further, a circulating pump outlet valve is installed on the water outlet pipeline of the circulating pump.

[0008] Further, a temperature sensor is installed on the water inlet of the wall type heat exchanger.

[0009] Further, the circulating pump is a fixed-frequency circulating pump.

[0010] Further, a controller is further included, the controller is signal connected with the temperature sensor, and is control connected with the heat network water import valve and the circulating pump outlet valve.

[0011] Further, the circulating pump is a variable-frequency circulating pump.

[0012] Further, a controller is further included, the controller is signal connected with the temperature sensor, and is control connected with the circulating pump.

[0013] Further, the wall type heat exchanger is a light pipe heat exchanger, a finned tube heat exchanger, a brazed heat exchanger or a fully-welded plate heat exchanger.

[0014] Further, the heat network water export valve and the heat network water import valve are ball valves or butterfly valves.

[0015] Compared with the prior art, the utility model has the following beneficial effects: the utility model discloses a circulating pump and drains the hot water after heat exchange of the wall type heat exchanger back to the water inlet of the wall type heat exchanger, improves the heat network water temperature that enters the wall type heat exchanger in the mixed water mode, can improve the temperature of the water inlet of the wall type heat exchanger to the flue gas dew point temperature above, thereby effectively avoiding the production of condensate water, and solving the problem of condensate water. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0017] Figure 1 The structure diagram of the system for preventing the partition wall type flue gas heat exchanger from generating condensate water is shown.

[0018] In the drawings, 1 is a heat network water outlet valve, 2 is a partition wall type heat exchanger, 3 is a temperature sensor, 4 is a heat network water inlet valve, 5 is a circulating pump, 6 is a check valve, and 7 is a circulating pump outlet valve. Specific embodiments

[0019] The technical solutions of the present application will be described below in conjunction with the embodiments. Obviously, the described embodiments are some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0020] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0021] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present utility model, "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a communication between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to the specific circumstances.

[0022] like Figure 1 As shown, an embodiment of the present invention provides a system for preventing condensation water from being generated in a partition-type flue gas heat exchanger, comprising: a hot water network outlet valve 1, a partition-type heat exchanger 2, a hot water network inlet valve 4 and a circulation pump 5; the hot water network outlet valve 1 is arranged on the outside of the water outlet of the partition-type heat exchanger 2, the hot water network inlet valve 4 is arranged on the outside of the water inlet of the partition-type heat exchanger 2, the water inlet of the circulation pump 5 is connected between the water outlet of the partition-type heat exchanger 2 and the hot water network outlet valve 1 through a pipeline, and the water outlet of the circulation pump 5 is connected between the water inlet of the partition-type heat exchanger 2 and the hot water network inlet valve 4 through a pipeline, so that at least a portion of the hot water after heat exchange flows back to the water inlet of the partition-type heat exchanger 2 through the circulation pump 5. The utility model uses a circulating pump 5 to guide the hot water after heat exchange in the partition wall heat exchanger 2 back to the water inlet of the partition wall heat exchanger 2, and increases the temperature of the hot network water entering the partition wall heat exchanger 2 in a mixed water manner, which can increase the temperature of the water inlet of the partition wall heat exchanger 2 to above the dew point temperature of the flue gas, thereby effectively avoiding the generation of condensed water and solving the problem of condensed water.

[0023] In one embodiment of the present invention, a check valve 6 is installed on the outlet pipe of the circulating pump 5. The check valve 6 prevents bypass of the heating network water circulating pump 5 when the circulating pump 5 stops. Preferably, a circulating pump outlet valve 7 is installed on the outlet pipe of the circulating pump 5. The circulating pump outlet valve 7 regulates the flow rate of the circulating pump 5 and also shuts off the circulating pump 5 during maintenance.

[0024] In one aspect of the embodiment of the utility model, the water inlet of the partition wall type heat exchanger 2 is provided with a temperature sensor 3. The temperature sensor 3 is used to measure the temperature of hot water mixed by the heat network water inlet pipe and the circulating pump 5 outlet pipe. Optionally, the temperature sensor 3 can be connected with a display or an alarm, which sends an alarm when the temperature measured by the temperature sensor 3 is lower than the flue gas dew point temperature. Preferably, the utility model further comprises a controller, which is signal connected with the temperature sensor 3 and is control connected with the heat network water inlet valve 4 and the circulating pump outlet valve 7. If the circulating pump 5 is a fixed frequency circulating pump, the controller can automatically adjust the heat network water inlet valve 4 and the circulating pump outlet valve 7 of the partition wall type heat exchanger according to the temperature measured by the temperature sensor 5, so as to ensure that the temperature of the heat network water entering the partition wall type heat exchanger 2 is higher than the dew point temperature of the flue gas. If the circulating pump 5 is a variable frequency circulating pump, the controller can automatically adjust the frequency and flow of the circulating pump 5 according to the temperature measured by the temperature sensor 5, so as to adjust the heat network water inlet temperature of the partition wall type heat exchanger 2. At the same time, in order to ensure power supply, the utility model further comprises a power supply, which is electrically connected with the controller. The power supply can also be used to supply power to electric valves, alarms and other electrical appliances. Preferably, the power supply is a storage battery.

[0025] The partition wall type heat exchanger 2 is a light pipe type heat exchanger, a finned tube type heat exchanger, a brazed type heat exchanger or a fully welded plate type heat exchanger. The heat network water outlet valve 1 and the heat network water inlet valve 4 are ball valves or butterfly valves. The function is to shut off when the partition wall type heat exchanger 2 is overhauled, and to adjust the flow of the heat network water entering the partition wall type heat exchanger 2.

[0026] Finally, it should be pointed out that: the above embodiments are only used to illustrate the technical solutions of the utility model, but not to limit them; although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the utility model.

Claims

1. A system for preventing the generation of condensate in a wall-type flue gas heat exchanger, characterized in that, The utility model relates to a heat exchanger with a circulating pump, comprising: a heat network water outlet valve (1), a heat exchanger (2), a heat network water inlet valve (4) and a circulating pump (5); the heat network water outlet valve (1) is arranged outside the water outlet of the heat exchanger (2), the heat network water inlet valve (4) is arranged outside the water inlet of the heat exchanger (2), the water inlet of the circulating pump (5) is connected between the water outlet of the heat exchanger (2) and the heat network water outlet valve (1) through a pipeline, and the water outlet of the circulating pump (5) is connected between the water inlet of the heat exchanger (2) and the heat network water inlet valve (4) through a pipeline, so that at least part of the heat-exchanged hot water is returned to the water inlet of the heat exchanger (2) through the circulating pump (5).

2. The system for preventing the generation of condensate water in a regenerative flue gas heat exchanger according to claim 1, characterized in that, A check valve (6) is installed on the water outlet pipeline of the circulating pump (5).

3. The system for preventing the generation of condensate water in a regenerative flue gas heat exchanger according to claim 1, characterized in that, A circulating pump outlet valve (7) is installed on the water outlet pipeline of the circulating pump (5).

4. The system for preventing the generation of condensate water in a regenerative flue gas heat exchanger according to claim 3, characterized in that, A temperature sensor (3) is installed on the water inlet of the heat exchanger (2).

5. The system for preventing the generation of condensate water in a regenerative flue gas heat exchanger according to claim 4, characterized in that, The circulating pump (5) is a fixed-frequency circulating pump.

6. The system for preventing the generation of condensate water in a wall-type flue gas heat exchanger according to claim 5, characterized in that, A controller is further included, which is signal-connected with the temperature sensor (3) and control-connected with the heat network water inlet valve (4) and the circulating pump outlet valve (7).

7. The system for preventing the generation of condensate water in a regenerative flue gas heat exchanger according to claim 4, characterized in that, The circulating pump (5) is a variable-frequency circulating pump.

8. The system for preventing the generation of condensate water in a wall-type flue gas heat exchanger according to claim 7, characterized in that, A controller is further included, which is signal-connected with the temperature sensor (3) and control-connected with the circulating pump (5).

9. The system for preventing the generation of condensate water in a regenerative flue gas heat exchanger according to claim 1, characterized in that, The heat exchanger (2) is a light-tube heat exchanger, a finned-tube heat exchanger, a brazed heat exchanger or a fully-welded plate heat exchanger.

10. The system for preventing the generation of condensate water in a wall-type flue gas heat exchanger according to any one of claims 1 to 9, characterized in that, The heat network water outlet valve (1) and the heat network water inlet valve (4) are ball valves or butterfly valves.

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