Fuel gas heat exchange system of heating furnace

Abstract

The utility model belongs to the technical field of heating furnace energy conservation, and particularly relates to a heating furnace fuel gas heat exchange system which comprises a heating furnace, a hearth inlet of the heating furnace is connected with a fuel gas inlet pipeline, the fuel gas inlet pipeline is sequentially connected with an inlet heat exchanger and a fuel gas liquid separation tank, and the inlet heat exchanger is connected with a preheating water pipeline. Fuel gas enters the fuel gas liquid separation tank for gas-liquid separation after being heated through the inlet heat exchanger and the preheating water pipeline, and then enters a hearth inlet of the heating furnace. A smoke outlet pipeline at a furnace top outlet of the heating furnace exchanges heat for air through the air preheater and then enters the chimney to be discharged, and an air inlet pipeline is connected to a hearth inlet of the heating furnace after heating inlet air through the air preheater. According to the fuel gas heat exchange system of the heating furnace, the temperature of the fuel gas can be increased to 75-85 DEG C, the heat load of the heating furnace is reduced, the fuel gas consumption is reduced, and the purposes of saving energy and reducing consumption are achieved. The system flow is simple, and the low-temperature heat utilization rate of the system can be effectively improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of energy-saving of heating furnaces, and in particular relates to a fuel gas heat exchange system of a heating furnace. Background Art

[0002] Depending on the process of the refining plant, the fuel gas consumption of the heating furnace accounts for about 20-70% of the total energy consumption of the plant. At the same time, the low-temperature heat of the refining plant is surplus and the utilization rate is low. Therefore, increasing the temperature of the fuel gas in the heating furnace, reducing the fuel gas consumption, and effectively utilizing the refining low-temperature heat have become important ways to save energy and reduce consumption of the plant. Summary of the invention

[0003] In view of the defects of the above-mentioned prior art, the purpose of the utility model is to provide a heating furnace fuel gas heat exchange system, which utilizes the surplus hot water from refining to heat the fuel gas, thereby increasing the temperature of the fuel gas entering the furnace, reducing the fuel gas consumption, and reducing the overall energy consumption of the device.

[0004] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is: a heating furnace fuel gas heat exchange system, including a heating furnace, the furnace inlet of the heating furnace is connected to the fuel gas inlet pipeline, the fuel gas inlet pipeline is sequentially connected to the inlet heat exchanger and the fuel gas liquid separator tank, the inlet heat exchanger is connected to the preheated water pipeline, the fuel gas is increased in temperature through the inlet heat exchanger and the preheated water pipeline, enters the fuel gas liquid separator tank for gas-liquid separation, and then enters the furnace inlet of the heating furnace; the flue gas outlet pipeline of the furnace top outlet of the heating furnace is heat-exchanged with air through an air preheater and then enters the chimney for discharge, and the air inlet pipeline is connected to the furnace inlet of the heating furnace after heating the inlet air through the air preheater.

[0005] Furthermore, an induced draft fan is provided on the flue gas outlet pipeline at the rear of the air preheater to guide the flue gas to be discharged into the chimney.

[0006] Furthermore, a blower is provided on the air inlet pipeline at the rear of the air preheater to guide air into the furnace inlet of the heating furnace.

[0007] Furthermore, the preheating water pipeline is connected to the waste hot water pipeline network of the refining device.

[0008] Furthermore, the preheated water pipeline is connected to the shell side of the inlet heat exchanger, and the fuel gas inlet pipeline is connected to the tube side of the inlet heat exchanger.

[0009] Furthermore, in the preheated water pipeline, the preheated water inlet temperature before heat exchange in the inlet heat exchanger is 92-98°C and the pressure is 0.55-0.75MpaG, and the preheated water outlet temperature after heat exchange is 65-75°C and the pressure is 0.25-0.4MpaG.

[0010] Furthermore, in the fuel gas inlet pipeline, the fuel gas inlet temperature before heat exchange in the inlet heat exchanger is 10-30°C, the pressure is 0.3-0.6 MpaG, and the fuel gas outlet temperature after heat exchange is 75-85°C.

[0011] Furthermore, the pressure of the fuel gas separation tank is 0.24-0.5MpaG.

[0012] Furthermore, in the air inlet pipeline, the outlet temperature of the air at the air preheater is 200-300°C.

[0013] Furthermore, in the flue gas outlet pipeline, the temperature of the flue gas at the outlet of the air preheater is 120-130°C.

[0014] Based on the above technical solution, high-temperature hot water produced by the low-temperature heat source of the refining device is used to heat the heating furnace fuel gas, thereby increasing the temperature of the fuel gas entering the heating furnace, thereby reducing the fuel gas consumption and effectively utilizing the low-temperature heat.

[0015] The beneficial effects of the utility model are as follows: the heating furnace fuel gas heat exchange system of the utility model can increase the fuel gas temperature to 75-85°C, reduce the heat load of the heating furnace, reduce the fuel gas consumption, and achieve the purpose of energy saving and consumption reduction. The system flow is simple and can effectively improve the low-temperature heat utilization rate of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a process flow chart of the heating furnace fuel gas heat exchange system of the utility model;

[0017] In the figure: 1. preheated water inlet pipeline, 2. fuel gas inlet pipeline, 3. inlet heat exchanger, 4. preheated water outlet pipeline, 5. fuel gas separator tank, 6. heating furnace, 7. blower, 8. air preheater, 9. induced draft fan, 10. chimney, 11. flue gas outlet pipeline, 12. air inlet pipeline. DETAILED DESCRIPTION

[0018] In order to make the structure and function of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0019] See attached Figure 1A heating furnace fuel gas heat exchange system comprises a heating furnace 6, an inlet heat exchanger 3, a fuel gas liquid separator 5 and an air preheater 8, wherein the furnace inlet of the heating furnace 6 is connected to a fuel gas inlet pipeline, the inlet heat exchanger has a tube side and a shell side, the fuel gas inlet pipeline 2 is sequentially connected to the tube side of the inlet heat exchanger 3 and the fuel gas liquid separator 5, the shell side inlet and outlet of the inlet heat exchanger 3 are connected to a preheated water outlet pipeline 4 and a preheated water inlet pipeline 1, the preheated water outlet pipeline 4 and the preheated water inlet pipeline 1 are connected to the waste hot water network of the refining device, so as to circulate, the fuel gas enters the fuel gas after the temperature is increased through the inlet heat exchanger 3 and the preheated water pipeline The gas-liquid separator 5 performs gas-liquid separation, and then the gas enters the furnace entrance of the heating furnace 6; the air preheater 8 is provided with an air channel and a smoke channel, and the smoke outlet on the top of the heating furnace 6 is connected with the smoke channel of the air preheater 8, the induced draft fan 9 and the chimney 10 through a smoke outlet pipeline 11. The smoke outlet pipeline 11 heats the air through the air preheater 8, and then guides the smoke to be discharged to the chimney 10 through the induced draft fan 9 arranged at the rear of the air preheater 8; the air inlet pipeline 12 heats the inlet air through the air channel of the air preheater 8, and then delivers the hot air to the furnace entrance of the heating furnace 6 through the blower 7 arranged at the rear of the air preheater 8.

[0020] Furthermore, the inlet temperature of the high-temperature hot water in the preheated water inlet pipeline 1 is 92-98°C and the pressure is 0.55-0.75MpaG, and the outlet temperature of the low-temperature hot water in the preheated water outlet pipeline 4 is 65-75°C and the pressure is 0.25-0.4MpaG.

[0021] Furthermore, in the fuel gas inlet pipeline 2, the fuel gas inlet temperature before heat exchange in the inlet heat exchanger is 10-30°C, the pressure is 0.3-0.6 MpaG, and the fuel gas outlet temperature after heat exchange is 75-85°C.

[0022] Furthermore, the pressure of the fuel gas separation tank is 0.24-0.5MpaG.

[0023] Furthermore, in the air inlet pipeline 12, the outlet temperature of the air at the air preheater 8 is 200-300°C.

[0024] Furthermore, in the flue gas outlet pipeline 11, the temperature of the flue gas at the outlet of the air preheater 8 is 120-130°C.

[0025] The heating furnace fuel gas heat exchange system of the utility model exchanges heat between the fuel gas and the high-temperature hot water generated by the low-temperature heat source, increases the temperature of the fuel gas entering the heating furnace, mixes the fuel gas with the hot air, burns and releases heat in the furnace, heats the process medium, and the flue gas on the furnace top exchanges heat with the air and is discharged to the chimney. The surplus hot water from refining is used to heat the fuel gas, increases the temperature of the fuel gas entering the furnace, reduces the fuel gas consumption, and achieves the purpose of energy saving and consumption reduction. The specific description is as follows: the temperature of the fuel gas before heat exchange is 15-20℃, the pressure is 0.4-0.5 MpaG, and the flow rate is 415Nm³ / h. The pressure before preheating water is 0.70-0.72MpaG, the temperature is 92-95℃, and the flow rate is 1.0t / h. The pressure after preheating water is 0.27-0.29MpaG, the temperature is 68-72℃, and the temperature of the fuel gas after heat exchange with preheating water is increased to 78-80℃. The fuel gas separator tank is 0.24-0.26MpaG, the temperature of the air after preheating is 270-280℃, and the exhaust gas temperature is 120-125℃. Under the condition that other conditions remain unchanged, the fuel gas consumption is reduced from 415Nm³ / h to 410Nm³ / h, which is reduced by 5 Nm³ / h, achieving the purpose of energy saving and consumption reduction.

[0026] The utility model has a simple process, fewer changes, and only adds one heat exchange device, with low investment. The heat source used is high-temperature hot water generated by the low-temperature heat of the refining device, which effectively improves the utilization rate of low-temperature heat; the fuel gas temperature can be increased to 75-85℃, reducing the heat load of the heating furnace and reducing the fuel gas consumption, achieving the purpose of energy saving and consumption reduction.

[0027] It should be noted that the parts not described in detail in the present invention are prior art.

[0028] The above examples are only the best embodiments of the present invention. Obviously, the present invention is not limited to the above examples, and there are many variations. All variations that can be directly derived or associated with the contents disclosed by a person skilled in the art should be considered as the protection scope of the present invention.

Claims

1. A heating furnace fuel gas heat exchange system, characterized in that: It includes a heating furnace, wherein the furnace inlet of the heating furnace is connected to a fuel gas inlet pipeline, the fuel gas inlet pipeline is sequentially connected to an inlet heat exchanger and a fuel gas liquid separator tank, the inlet heat exchanger is connected to a preheated water pipeline, the fuel gas is heated by the inlet heat exchanger and the preheated water pipeline, enters the fuel gas liquid separator tank for gas-liquid separation, and then enters the furnace inlet of the heating furnace; the flue gas outlet pipeline at the furnace top outlet of the heating furnace exchanges heat with air through an air preheater, and then enters the chimney for discharge, and the air inlet pipeline is connected to the furnace inlet of the heating furnace after heating the inlet air through the air preheater.

2. A heating furnace fuel gas heat exchange system according to claim 1, characterized in that: The flue gas outlet pipeline is provided with an induced draft fan on the rear of the air preheater to guide the flue gas to be discharged to the chimney.

3. A heating furnace fuel gas heat exchange system according to claim 1, characterized in that: The air inlet pipeline is provided with a blower on the rear of the air preheater to guide the air into the furnace inlet of the heating furnace.

4. A heating furnace fuel gas heat exchange system according to claim 1, characterized in that: The preheating water pipeline is connected to the waste hot water network of the refining device.

5. The heating furnace fuel gas heat exchange system according to claim 1, characterized in that: The preheated water pipeline is connected to the shell side of the inlet heat exchanger, and the fuel gas inlet pipeline is connected to the tube side of the inlet heat exchanger.

6. A heating furnace fuel gas heat exchange system according to claim 1, characterized in that: In the preheated water pipeline, the preheated water inlet temperature before heat exchange in the inlet heat exchanger is 92-98°C and the pressure is 0.55-0.75MpaG, and the preheated water outlet temperature after heat exchange is 65-75°C and the pressure is 0.25-0.4MpaG.

7. The heating furnace fuel gas heat exchange system according to claim 1, characterized in that: In the fuel gas inlet pipeline, the fuel gas inlet temperature before heat exchange in the inlet heat exchanger is 10-30°C, the pressure is 0.3-0.6 MpaG, and the fuel gas outlet temperature after heat exchange is 75-85°C.

8. The heating furnace fuel gas heat exchange system according to claim 1, characterized in that: The fuel gas liquid separation tank has a pressure of 0.24-0.5MpaG.

9. The heating furnace fuel gas heat exchange system according to claim 1, characterized in that: In the air inlet pipeline, the air outlet temperature of the air preheater is 200-300°C.

10. The heating furnace fuel gas heat exchange system according to claim 1, characterized in that: In the flue gas outlet pipeline, the temperature of the flue gas at the outlet of the air preheater is 120-130°C.

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