A flue gas waste heat recovery and utilization system for a fertilizer production process

Abstract

The utility model discloses a kind of flue gas waste heat recovery and utilization system for fertilizer production process, including being located on the flue gas pipeline flue gas heat exchanger, the water inlet of the flue gas heat exchanger is connected with the cold water tank water outlet by water inlet pipeline, the water outlet of the flue gas heat exchanger is connected with the water inlet of hot water tank by water outlet pipeline, the hot water tank water outlet is connected with hot water pipeline one end, hot water pipeline other end is connected with first heating pipeline and second heating pipeline respectively, the first heating pipeline is passed into to the heating jacket of material tank, the second heating pipeline is passed into to the heating coil of reaction kettle;The utility model realizes the efficient recovery of waste heat in high-temperature flue gas, reduces enterprise energy consumption and production cost.

Description

Technical Field

[0001] This utility model relates to the field of waste heat recovery and utilization technology in fertilizer production, and in particular to a waste heat recovery and utilization system for flue gas in fertilizer production processes. Background Technology

[0002] Flue gas heat loss has always been a major component of heat energy loss in industrial production, and its efficient recovery and utilization has become a core research direction and implementation focus in the field of heat energy recovery. Against the backdrop of a escalating global energy crisis and increasingly stringent environmental regulations, the current problem of direct emissions of high-temperature flue gas in industrial production not only causes enormous energy waste but also creates a prominent contradiction with the development needs of energy conservation and emission reduction. According to relevant statistics, approximately 30%-50% of energy in the industrial sector is lost as waste heat. Among various waste heat resources, flue gas waste heat consistently ranks first, and the large amount of heat energy it contains remains unutilized, becoming one of the important reasons for the high energy consumption of enterprises. This extensive emission model not only increases the production costs of enterprises and exacerbates the tight energy supply and demand situation, but may also bring additional environmental governance pressures. Against this backdrop, the development of a flue gas waste heat recovery and comprehensive utilization system, which achieves efficient recovery of waste heat from high-temperature flue gas through scientific and technological means, can not only directly reduce enterprise energy consumption and production costs, but also promote the cascade utilization of energy, ultimately achieving significant comprehensive economic and environmental benefits. Utility Model Content

[0003] The purpose of this invention is to overcome the above-mentioned shortcomings and provide a flue gas waste heat recovery and utilization system for fertilizer production processes, so as to achieve efficient recovery of waste heat in high-temperature flue gas and reduce enterprise energy consumption and production costs.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: a flue gas waste heat recovery and utilization system for fertilizer production process, including a flue gas heat exchanger installed on a hot flue gas pipeline, the inlet of the flue gas heat exchanger being connected to the outlet of a cold water tank through an inlet pipe, the outlet of the flue gas heat exchanger being connected to the inlet of a hot water tank through an outlet pipe, the outlet of the hot water tank being connected to one end of a hot water pipeline, and the other end of the hot water pipeline being connected to a first heating pipeline and a second heating pipeline respectively, the first heating pipeline being inserted into the heating jacket of the material tank, and the second heating pipeline being inserted into the heating coil of the reaction vessel.

[0005] Preferably, the outlet of the heating jacket is connected to the return outlet of the cold water tank via a first return water pipeline.

[0006] Preferably, the outlet of the heating coil is connected to the return outlet of the cold water tank via a second return water pipeline.

[0007] Preferably, the inlet pipe, outlet pipe, hot water pipeline, first heating pipeline, second heating pipeline, first return water pipeline and second return water pipeline are all equipped with corresponding valves.

[0008] Preferably, a cold water pump is installed on the water inlet pipe, and a hot water pump is installed on the hot water pipeline.

[0009] Preferably, the cold water tank is provided with a first vent pipe at the top, and the hot water tank is provided with a second vent pipe at the top.

[0010] Preferably, the hot water pipeline is also connected to the hot water tank return port through a first circulation pipeline, and a valve is provided on the first circulation pipeline.

[0011] Preferably, the water inlet pipe is also connected to the cold water tank return port through a second circulation pipeline, and a valve is provided on the second circulation pipeline.

[0012] Preferably, both the cold water tank and the hot water tank are provided with water inlets.

[0013] Preferably, the water in the cold water tank and the hot water tank is demineralized water.

[0014] The beneficial effects of this utility model are as follows: This utility model uses a heat exchanger with demineralized water as the heat exchange medium. It utilizes the circulating demineralized water to exchange heat with high-temperature flue gas. The demineralized water after heat exchange is recycled and reused through a jacket and coil. While reducing the temperature of the high-temperature flue gas to meet the emission conditions, the recycled heat is fully utilized, thereby reducing the total energy consumption required by the production system. It achieves efficient recovery of waste heat in high-temperature flue gas, reducing the energy consumption and production costs of enterprises. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of a flue gas waste heat recovery and utilization system used in fertilizer production. Detailed Implementation

[0016] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0017] like Figure 1 As shown, a flue gas waste heat recovery and utilization system for fertilizer production includes a flue gas heat exchanger 2 installed on a hot flue gas pipeline 1. The inlet of the flue gas heat exchanger 2 is connected to the outlet of a cold water tank 4 via an inlet pipe 3. The outlet of the flue gas heat exchanger 2 is connected to the inlet of a hot water tank 6 via an outlet pipe 5. The outlet of the hot water tank 6 is connected to one end of a hot water pipeline 7. The other end of the hot water pipeline 7 is connected to a first heating pipeline 8 and a second heating pipeline 9, respectively. The first heating pipeline 8 is inserted into the heating jacket 10.1 of the material tank 10, and the second heating pipeline 9 is inserted into the heating coil 11.1 of the reaction vessel 11.

[0018] Preferably, the outlet of the heating jacket 10.1 is connected to the return port of the cold water tank 4 through the first return water pipeline 12.

[0019] Preferably, the outlet of the heating coil 11.1 is connected to the return outlet of the cold water tank 4 through the second return water pipeline 13.

[0020] Preferably, the inlet pipe 3, outlet pipe 5, hot water pipe 7, first heating pipe 8, second heating pipe 9, first return water pipe 12 and second return water pipe 13 are all equipped with corresponding valves.

[0021] Preferably, a cold water pump 3.1 is provided on the water inlet pipe 3, and a hot water pump 7.1 is provided on the hot water pipeline 7.

[0022] Preferably, the cold water tank 4 is provided with a first vent pipe 4.1 at its top, and the hot water tank 6 is provided with a second vent pipe 6.1 at its top. In this embodiment, the vent pipes at the top of the hot water tank 6 and the cold water tank 4 can prevent the accumulation of more water vapor in the tank due to the rise in water temperature, which could cause pressure buildup.

[0023] Preferably, the hot water pipeline 7 is also connected to the return port of the hot water tank 6 via a first circulation pipeline 14, and a valve is provided on the first circulation pipeline 14. By setting up the first circulation pipeline 14, the corresponding valve can be opened to allow hot water to circulate into the hot water tank 6 through the first circulation pipeline 14, and the hot water flow rate can be adjusted to ensure the liquid level balance in the hot water tank 6.

[0024] Preferably, the water inlet pipe 3 is also connected to the return port of the cold water tank 4 via a second circulation pipeline 15, and a valve is provided on the second circulation pipeline 15. By setting up the second circulation pipeline 15, the corresponding valve can be opened to allow cold water to circulate into the cold water tank 4 through the second circulation pipeline 15, and the flow rate of cold water can be adjusted to ensure the liquid level balance in the cold water tank 4.

[0025] Preferably, both the cold water tank 4 and the hot water tank 6 are equipped with water inlets. Since the water vapor generated in the hot water tank 6 and the cold water tank 4 will be discharged through the vent pipe, resulting in some water loss, water needs to be replenished according to the liquid levels in the cold water tank 4 and the hot water tank 6 after the system has been running for a period of time.

[0026] Preferably, the water in the cold water tank 4 and the hot water tank 6 is demineralized water. The use of demineralized water as the medium in this system aims to effectively prevent scale buildup in the heat exchanger, cold and hot water tanks, jacket, coils, and pipelines, thereby reducing the system's heat exchange efficiency.

[0027] In addition, in this embodiment, the flue gas heat exchanger typically adopts a partitioned heat exchanger (such as a plate or tube structure), where high-temperature flue gas (100-150°C) and low-temperature medium (demineralized water) flow in opposite directions within an isolated flow channel and conduct heat through the metal wall.

[0028] The working principle of this embodiment is as follows: As attached Figure 1 As shown, a flue gas heat exchanger is installed on the hot flue gas pipeline to recover heat from the flue gas at approximately 100-150℃. The heat exchange medium, demineralized water, in the cold water tank is pumped to the heat exchanger to exchange heat with the hot flue gas. The demineralized water is then stored in a hot water tank. When the water level reaches a certain threshold, the hot water pump is activated. One path of the hot demineralized water passes through the heating jacket of the feed tank to heat the material, increasing the feed temperature of the production system and reducing the heat consumption required by the system. The other path passes through the heating coil to heat the reactor, bringing it to the required production temperature. The heat from the demineralized water is then returned to the cold water tank. The cold and hot water tanks act as buffers, while the cold and hot water pumps provide power, allowing the demineralized water to circulate and continuously supply heat to the feed tank and heating coil. This effectively recovers and utilizes the heat from the hot flue gas, reducing the final exhaust temperature and thus conserving heat for the production system, reducing production costs. In this system, to ensure maximum heat recovery and utilization, all pipelines, storage tanks, and jackets are externally insulated to maximize heat recovery and utilization. Simultaneously, circulation pipelines are installed at the outlets of the cold and hot water pumps to adjust the flow rates and maintain liquid level balance in the cold and hot water tanks. Valves are installed on both hot water pipelines to regulate the hot water flow rate according to actual production needs, allowing for more flexible distribution of the recovered heat.

[0029] According to data statistics from actual production processes, after the implementation of this utility model, the amount of fuel required for the company's production is reduced by about 10%, and the efficiency of the production system is increased by about 3%. It has effectively and reasonably realized the recovery and utilization of waste heat from high-temperature flue gas, fully demonstrating the feasibility and practicality of this patent.

[0030] The above embodiments are merely preferred technical solutions of this utility model and should not be considered as limitations on this utility model. The protection scope of this utility model should be the technical solution described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the protection scope of this utility model.

Claims

1. A flue gas waste heat recovery and utilization system for fertilizer production process, comprising a flue gas heat exchanger (2) installed on a hot flue gas pipeline (1), wherein the inlet of the flue gas heat exchanger (2) is connected to the outlet of a cold water tank (4) via an inlet pipe (3), and the outlet of the flue gas heat exchanger (2) is connected to the inlet of a hot water tank (6) via an outlet pipe (5), characterized in that: The outlet of the hot water tank (6) is connected to one end of the hot water pipeline (7), and the other end of the hot water pipeline (7) is connected to the first heating pipeline (8) and the second heating pipeline (9) respectively. The first heating pipeline (8) is connected to the heating jacket (10.1) of the material tank (10), and the second heating pipeline (9) is connected to the heating coil (11.1) of the reactor (11).

2. The flue gas waste heat recovery and utilization system for fertilizer production process according to claim 1, characterized in that: The outlet of the heating jacket (10.1) is connected to the return port of the cold water tank (4) through the first return water pipeline (12).

3. A flue gas waste heat recovery and utilization system for fertilizer production process according to claim 2, characterized in that: The outlet of the heating coil (11.1) is connected to the return port of the cold water tank (4) through the second return water pipeline (13).

4. A flue gas waste heat recovery and utilization system for fertilizer production process according to claim 3, characterized in that: The inlet pipe (3), outlet pipe (5), hot water pipe (7), first heating pipe (8), second heating pipe (9), first return water pipe (12) and second return water pipe (13) are all equipped with corresponding valves.

5. A flue gas waste heat recovery and utilization system for fertilizer production process according to claim 1, characterized in that: A cold water pump (3.1) is installed on the water inlet pipe (3), and a hot water pump (7.1) is installed on the hot water pipeline (7).

6. A flue gas waste heat recovery and utilization system for fertilizer production process according to claim 1, characterized in that: The cold water tank (4) is provided with a first exhaust pipe (4.1) at the top, and the hot water tank (6) is provided with a second exhaust pipe (6.1) at the top.

7. A flue gas waste heat recovery and utilization system for fertilizer production process according to claim 1, characterized in that: The hot water pipeline (7) is also connected to the return port of the hot water tank (6) through the first circulation pipeline (14), and a valve is provided on the first circulation pipeline (14).

8. A flue gas waste heat recovery and utilization system for fertilizer production process according to claim 1, characterized in that: The water inlet pipe (3) is also connected to the return port of the cold water tank (4) through the second circulation pipeline (15), and a valve is provided on the second circulation pipeline (15).

9. A flue gas waste heat recovery and utilization system for fertilizer production process according to claim 8, characterized in that: Both the cold water tank (4) and the hot water tank (6) are equipped with water inlets.

10. A flue gas waste heat recovery and utilization system for fertilizer production process according to claim 1, characterized in that: The water in the cold water tank (4) and the hot water tank (6) is desalinated water.

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