Steam condensate waste heat utilization system in solid caustic soda production
By designing a steam condensate waste heat utilization system in solid alkali production and using heat exchangers and heating devices to exchange heat, the problem of waste heat in secondary steam condensate in solid alkali production is solved, resource utilization and production efficiency are improved, and production costs are reduced.
Patent Information
- Application Number
- CN202420629779.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-28
- Publication Date
- 2025-06-17
- Estimated Expiration
- 2034-03-28
AI Technical Summary
The waste of heat in secondary steam condensate in solid alkali production leads to high circulating water temperature, waste of heat energy, large steam consumption, and low steam pressure for production, affecting the yield of sheet and pellet alkali.
Design a waste heat utilization system for steam condensate water in solid alkali production, including heat exchange device and heating device. The heat exchange device exchanges heat through heat exchangers, condensate water supply pipelines and return water supply pipelines, and uses the waste heat of condensate water for heating, and returns the hot water to the circulating water pool through the condensate water return water pipeline to improve resource utilization.
It effectively solves the waste of heat in secondary steam condensate in solid alkali production, improves resource utilization, reduces steam consumption, saves production costs, stabilizes system pressure, and improves production efficiency.
Smart Images
Figure CN222993000U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a waste heat reuse system in solid caustic soda production, in particular to a waste heat utilization system for steam condensate in solid caustic soda production, belonging to the technical field of solid caustic soda production devices. Background Technique
[0002] The solid caustic soda production process can be divided into three stages: (1) The alkali solution is concentrated from 32% concentration to 61%. This stage can be carried out in a falling film evaporator. The heating source is secondary steam; (2) The 61% alkali solution is further concentrated into a 73% alkali solution by a rising film evaporator. The heating source is high-pressure steam; (3) The 73% alkali solution passes through a falling film concentrator, using molten salt as the heat carrier, concentrating the alkali solution into molten caustic soda, and then forming sheet (granular) solid caustic soda through a flake caustic soda machine and then cooling and forming into sheet or granular bagged alkali.
[0003] In the above process, about 100 m³ of secondary steam condensate with a temperature of about 90 - 100 °C is generated per hour. After removing 10 m³ / hour for primary brine salt dissolving, the remaining 90 m³ of secondary steam condensate directly enters the circulating water pool, which not only causes the temperature of the circulating water to be too high, but also wastes a large amount of thermal energy. In addition, in winter, steam is required in the factory area to exchange heat with the heating return water, and the amount of steam required by the heating unit is large, which not only causes a large total steam consumption, but also leads to a low steam pressure for production, thereby affecting the production of flake and granular caustic soda. Summary of the Invention
[0004] The purpose of the utility model is to provide a reasonably designed waste heat utilization system for steam condensate in solid caustic soda production to solve the above technical problems. This system can effectively solve the waste of heat in secondary steam condensate in solid caustic soda production, improve resource utilization rate, reduce steam consumption, save production costs, stabilize system pressure, and improve production efficiency.
[0005] To achieve the above purpose, the utility model provides the following technical solutions:
[0006] A waste heat utilization system for steam condensate in solid caustic soda production at least includes a heat exchange device and a heating device. The heat exchange device at least includes a heat exchanger (1) and an evaporation condensate water pipeline, and the heating device at least includes a heating upper water pipeline (7) and a heating return water pipeline (8).
[0007] Further, the evaporation condensate water pipeline includes a condensate upper water pipeline (5) and a condensate return water pipeline (6). The condensate upper water pipeline (5) is connected to the bottom end of the heat exchanger (1), the condensate return water pipeline (6) is connected to the top end of the heat exchanger (1), the heating upper water pipeline (7) is connected to the top end of the heat exchanger (1), and the heating return water pipeline (8) is connected to the bottom end of the heat exchanger (1).
[0008] Further, it further includes a condensate water tank (2), and the condensate water tank (2) is communicated with a condensate water supply pipeline (5).
[0009] Further, it further includes a water tank (3). A make-up water pipeline (11) is provided between the water tank (3) and a heating water supply pipeline (7). The water inlet of the water tank (3) is connected to a condensate water return pipeline (6) through a pipeline. The heated condensate water is used to supplement water to the heating pipeline, replacing the original primary water make-up, improving the utilization efficiency of water resources and saving water resources.
[0010] Further, the end of the condensate water return pipeline (6) is communicated with a circulating water tank (4).
[0011] Preferably, a condensate water circulation branch pipe (13) is provided between the condensate water supply pipeline (5) and the condensate water return pipeline (6). A valve is provided on the condensate water circulation branch pipe (13). After the weather warms up and heating stops, this valve is opened, and the steam condensate directly enters the circulating water tank (4) from the condensate water return pipeline through the condensate water circulation branch pipe (13), stopping heat exchange.
[0012] Furthermore, thermometers (9) and pressure gauges (10) are provided on both the condensate water supply pipeline (5) and the condensate water return pipeline (6) to monitor the temperature and pressure of the water supply and return water in real time and ensure the heat exchange effect.
[0013] Further, a heating circulation pipeline (14) is provided on the make-up water pipeline (11). The heating circulation pipeline (14) has at least two parallel branches, and a valve is provided on each branch. By adjusting the opening and closing and the size of the valves, the heating return water can be circulated between the parallel branches, thereby controlling the water volume and water velocity of the heating return water entering the heat exchanger and improving the heat exchange efficiency.
[0014] Furthermore, thermometers (9) are provided on both the heating water supply pipeline (7) and the heating return pipeline (8) to monitor the heating temperature. A connecting pipe is provided between the heating water supply pipeline (7) and the heating return pipeline (8), and a valve is provided on the connecting pipe. If the temperature monitored by the thermometer provided on the heating return pipeline is high and meets the heating requirements, the valve provided on the connecting pipe can be opened, and the heating return water can supply heat to the whole plant through each heating branch pipe (12) without entering the heat exchanger for heat exchange.
[0015] Preferably, the heat exchanger (1) is a plate heat exchanger. The plate heat exchanger exchanges heat through thin rectangular channels, has a high heat exchange efficiency, a compact structure, a small floor area, is beneficial to space utilization, and the heat recovery rate can be as high as over 90%.
[0016] Compared with the prior art, the utility model can effectively solve the waste of heat in the secondary steam condensate during solid caustic soda production, improve the resource utilization rate, reduce steam consumption, reduce the amount of primary water used, save production costs, stabilize the system pressure, and improve production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 is a schematic structural diagram of the utility model.
[0018] As shown in the figure: 1 is a heat exchanger, 2 is a condensate tank, 3 is a water tank, 4 is a circulation pool, 5 is a condensate water supply pipeline, 6 is a condensate water return pipeline, 7 is a heating water supply pipeline, 8 is a heating water return pipeline, 9 is a thermometer, 10 is a pressure gauge, 11 is a make-up water pipeline, 12 is a heating branch pipe, 13 is a condensate water circulation branch pipe, and 14 is a heating circulation pipeline. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] The preferred embodiments of the utility model will be described in detail below.
[0020] Example 1: Refer to Figure 1 , which is a schematic structural diagram of Embodiment 1 of the utility model, including a heat exchange device and a heating device. The heat exchange device includes a heat exchanger 1, an evaporation condensate pipeline, and a condensate tank 2. The heat exchanger 1 is a plate heat exchanger, which exchanges heat through thin rectangular channels, has a high heat exchange efficiency, a compact structure, a small floor area, is beneficial to space utilization, and the heat recovery rate can be as high as over 90%. The evaporation condensate pipeline includes a condensate water supply pipeline 5 and a condensate water return pipeline 6. The water outlet of the condensate tank 2 is communicated with the condensate water supply pipeline 5. The condensate water supply pipeline 5 is communicated with the bottom end of the heat exchanger 1. The condensate water return pipeline 6 is communicated with the top end of the heat exchanger 1. The end of the condensate water return pipeline 6 is communicated with the circulation pool 4. The secondary steam condensate generated during solid caustic soda production is concentrated in the condensate tank. The amount of condensate water entering the heat exchanger is adjusted by controlling the valve on the condensate water supply pipeline 5. The heat-exchanged condensate water is introduced into the circulation pool 4 in the alkali workshop or the utility engineering workshop through the water outlet at the top of the heat exchanger by the condensate water return pipeline 6. Thermometers 9 and pressure gauges 10 are provided on both the condensate water supply pipeline 5 and the condensate water return pipeline 6 to monitor the temperature and pressure of the incoming and returning water in real time to ensure the heat exchange effect.
[0021] The heating device includes a heating supply pipeline 7, a heating return pipeline 8 and a water tank 3. The heating supply pipeline 7 is communicated with the top end of the heat exchanger 1, and the heating return pipeline 8 is communicated with the bottom end of the heat exchanger 1. A make-up water pipeline 11 is arranged between the water tank 3 and the heating supply pipeline 7. The water inlet of the water tank 3 is connected with the condensate return pipeline 6 through a pipeline. The condensate after heat exchange is used to supplement water to the heating pipeline, replacing the original primary water make-up, improving the utilization efficiency of water resources and saving water resources. The heating return water after heating is collected by each heating branch pipe 12 and then introduced into the heat exchanger through the heating return pipeline 8. After heat exchange with the high-temperature condensate flowing from bottom to top from top to bottom in the heat exchanger, the heating return water heated to the heating requirement passes through the heating supply pipeline 7 at the bottom end of the heat exchanger 1 and is introduced into each heating branch pipe 12 to heat the heating groups in the factory, and this cycle is repeated.
[0022] Embodiment 2: Compared with Embodiment 1, the difference in this embodiment is that: a condensate water circulation branch pipe 13 is arranged between the condensate water supply pipeline 5 and the condensate water return pipeline 6, and a valve is arranged on the condensate water circulation branch pipe 13. After the heating stops when the weather warms up, this valve is opened, and the steam condensate directly drains into the circulation pool 4 through the condensate water circulation branch pipe 13, and the heat exchange stops.
[0023] Embodiment 3: Compared with Embodiment 1 or 2, the difference in this embodiment is that: a heating water circulation pipeline 14 is arranged on the make-up water pipeline 11. The heating water circulation pipeline 14 has at least 2 parallel branches, and each branch is provided with a valve. By adjusting the opening and closing and the size of the valve, the heating return water can be circulated among the parallel branches, so as to control the water volume and water speed of the heating return water entering the heat exchanger and improve the heat exchange efficiency.
[0024] Embodiment 4: Compared with any one of Embodiments 1 to 3, the difference in this embodiment is that: thermometers 9 are arranged on both the heating supply pipeline 7 and the heating return pipeline 8 to monitor the heating temperature. A communicating pipe is arranged between the heating supply pipeline 7 and the heating return pipeline 8, and a valve is arranged on the communicating pipe. If the temperature monitored by the thermometer arranged on the heating return pipeline is relatively high and meets the heating requirement, the valve arranged on the communicating pipe can be opened, and the heating return water can directly supply heat to the whole factory through each heating branch pipe 12 without entering the heat exchanger for heat exchange.
[0025] The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the inventive concept of the present invention, several changes and improvements can still be made, and these all belong to the protection scope of the present invention.
Claims
1. A system for utilizing waste heat from steam condensed water in solid caustic soda production, characterized in that: The invention at least comprises a heat exchange device and a heating device, wherein the heat exchange device at least comprises a heat exchanger and an evaporative condensing water pipeline, wherein the evaporative condensing water pipeline comprises a condensing water supply pipeline and a condensing water return pipeline, wherein the condensing water supply pipeline is connected to the bottom end of the heat exchanger, and the condensing water return pipeline is connected to the top end of the heat exchanger, and the heating device at least comprises a heating water supply pipeline and a heating water return pipeline, wherein the heating water supply pipeline is connected to the top end of the heat exchanger, and the heating water return pipeline is connected to the bottom end of the heat exchanger.
2. The system for utilizing waste heat of steam condensed water in solid caustic soda production according to claim 1, characterized in that: It also includes a condensed water tank, which is connected to the condensed water supply pipeline.
3. The system for utilizing waste heat of steam condensed water in solid caustic soda production according to claim 1 or 2, characterized in that: It also includes a water tank, a water supply pipeline is arranged between the water tank and the heating water supply pipeline, and the water inlet of the water tank is connected to the condensed water return pipeline through the pipeline.
4. The system for utilizing waste heat of steam condensed water in solid caustic soda production according to claim 3, characterized in that: The end of the condensed water return pipeline is connected to the circulating water pool.
5. The system for utilizing waste heat of steam condensed water in solid caustic soda production according to claim 3, characterized in that: A condensate circulation branch pipe is provided between the condensate supply pipeline and the condensate return pipeline, and a valve is provided on the condensate circulation branch pipe.
6. The system for utilizing waste heat of steam condensed water in solid caustic soda production according to claim 3, characterized in that: The condensate supply pipeline and the condensate return pipeline are both provided with a thermometer and a pressure gauge.
7. The system for utilizing waste heat of steam condensed water in solid caustic soda production according to claim 3, characterized in that: The water supply pipeline is provided with a heating circulation pipeline, and the heating circulation pipeline is provided with at least two parallel branches.
8. The system for utilizing waste heat of steam condensed water in solid caustic soda production according to claim 3, characterized in that: The heating water supply pipeline and the heating water return pipeline are both provided with thermometers.
9. The system for utilizing waste heat of steam condensed water in solid caustic soda production according to claim 3, characterized in that: The heat exchanger is a plate heat exchanger.