Conduction oil flash evaporation system

Abstract

A heat-conducting oil flash evaporation system relates to the field of heat-conducting oil flash evaporation and comprises a heat-conducting oil furnace and n stages of flash evaporation tanks, the flash evaporation tanks supply heat to different heat users, the n stages of flash evaporation tanks comprise the ith-stage flash evaporation tank and the nth-stage flash evaporation tank, an outlet of the heat-conducting oil furnace is connected to the ith-stage flash evaporation tank and the nth-stage flash evaporation tank through a liquid inlet pipeline, and a liquid outlet of the heat-conducting oil furnace is connected to the nth-stage flash evaporation tank through a liquid outlet pipeline. The ith-stage flash tank is connected with a pipeline system for supplying liquid heat-conducting oil to the subsequent-stage flash tank and the heat-conducting oil furnace, the pipeline system comprises a circulating pipeline and an (i + 1) th-stage liquid inlet pipeline, the ith-stage flash tank is connected to the heat-conducting oil furnace through the circulating pipeline, the circulating pipeline is sequentially connected with a heat-conducting oil circulating pump and an adjusting valve in the flowing direction of the heat-conducting oil, and the (i + 1) th-stage liquid inlet pipeline is connected to the (i + 1) th-stage liquid inlet pipeline. The circulation pipeline is connected to the (i + 1) th stage of flash tank through the (i + 1) th stage of liquid inlet pipeline, and the pipeline connection point of the (i + 1) th stage of liquid inlet pipeline and the circulation pipeline is located between the heat-conducting oil circulation pump and the regulating valve; and the nth-stage flash tank is connected to the heat-conducting oil furnace through a final-stage circulating pipeline. And gas-phase heat-conducting oil with various temperatures can be output.

Description

Technical Field

[0001] The invention provides a heat transfer oil multi-stage flash evaporation system, which is applied to users who use heat transfer oil steam at multiple temperatures. Background Art

[0002] Gas phase thermal oil is widely used in industry, providing an efficient and reliable method to transfer heat energy. Gas phase thermal oil systems are particularly suitable for industrial processes that require high temperatures. Such systems can operate at higher temperatures than liquid phase systems, usually up to 400°C or even higher, and can provide very stable heat transfer performance. Compared with steam or electric heating, gas phase thermal oil systems can provide higher thermal efficiency and energy utilization in many cases. Gas phase thermal oil systems can provide very precise temperature control, which is very important for ensuring product quality and process safety. Gas phase thermal oil systems usually have lower operating pressures, which helps to improve the safety of the overall system. In industrial applications, these advantages of gas phase thermal oil systems make them an ideal choice for many high temperature processes and complex heating requirements. It is a common process method to use a thermal oil furnace + flash tank to reduce the high temperature liquid phase thermal oil output from the thermal oil furnace and then flash it into gas phase thermal oil in the flash tank.

[0003] For heat users who need a variety of gas-phase heat transfer oil temperatures, if each temperature level of gas-phase heat transfer oil is prepared using a separate heat transfer oil furnace + a flash tank, the required equipment is undoubtedly excessive, which increases investment and increases the floor space. Summary of the invention

[0004] The technical problem solved by the present application is: to overcome the deficiencies of the prior art, and to provide a thermal oil flash evaporation system, which uses a thermal oil furnace to output high-temperature liquid-phase thermal oil, and realizes the output of multi-temperature gas-phase thermal oil through multi-stage flash evaporation. The flash evaporation volume of the first stage is controlled by the outlet liquid-phase thermal oil temperature of the thermal oil furnace, and the flash evaporation volume of the second stage is controlled by controlling the amount of high-temperature condensate entering the second-stage flash tank, and so on. A thermal oil furnace can be used to realize the output of multi-temperature gas-phase thermal oil through multi-stage flash evaporation to meet the different needs of heat users.

[0005] The technical solutions provided by this application are as follows:

[0006] A thermal oil flash evaporation system comprises a thermal oil furnace and an n-stage flash tank, where n is an integer greater than 1, and the flash tanks are respectively converted into liquid thermal oil after supplying heat to different heat users and return to the flash tanks, and the n-stage flash tanks include an i-th flash tank and an n-th flash tank, where i+1≤n, and the outlet of the thermal oil furnace is connected to the i-th flash tank and the n-th flash tank through a liquid inlet pipeline, and the i-th flash tank is connected to a pipeline system for supplying liquid thermal oil to the subsequent flash tank and the thermal oil furnace, and the pipeline system includes the i-th flash tank. The i-th circulation pipeline and the i+1-th liquid inlet pipeline, the i-th flash tank is connected to the thermal oil furnace through the i-th circulation pipeline, along the flow direction of the thermal oil in the i-th circulation pipeline, the i-th circulation pipeline is sequentially connected with a thermal oil circulation pump and a regulating valve, the regulating valve is used to control the flow rate of the thermal oil, the i-th circulation pipeline is connected to the i+1-th flash tank through the i+1-th liquid inlet pipeline, and the pipeline connection point of the i+1-th liquid inlet pipeline and the circulation pipeline is located between the thermal oil circulation pump and the regulating valve;

[0007] The nth-stage flash tank is connected to the thermal oil boiler through the final i-stage circulation pipeline.

[0008] The j-th flash tank is connected to heat user j through an outlet pipeline, j∈[1-n], heat user j is connected to a condensate tank through a liquid return pipeline, and the condensate tank is connected to the j-th flash tank through a condensation pipeline.

[0009] The condensation pipeline is connected with a heat transfer oil condensate pump.

[0010] The liquid inlet pipeline is also connected to a branch pipeline, one end of the branch pipeline is connected to the liquid inlet pipeline, and the other end is connected to other flash tanks, the other flash tanks are x-th flash tanks, x∈[1, n] and x≠i, and the other end of the branch pipeline is specifically connected between the heat transfer oil circulation pump and the regulating valve on the x-th liquid inlet pipeline connected to the x-th flash tank.

[0011] The liquid inlet pipeline and the (i+1)th level liquid inlet pipeline are both provided with pressure reducing valves.

[0012] The position of the pressure reducing valve connected on the liquid inlet pipeline is: along the flow direction of the liquid-phase heat transfer oil in the liquid inlet pipeline, the connection point between the branch pipeline and the liquid inlet pipeline, and the pressure reducing valve are distributed on the liquid inlet pipeline in sequence; the position of the pressure reducing valve connected on the x-th level liquid inlet pipeline is: along the flow direction of the liquid-phase heat transfer oil in the x-th level liquid inlet pipeline, the connection point between the branch pipeline and the x-th level liquid inlet pipeline, and the pressure reducing valve are distributed on the x-th level liquid inlet pipeline in sequence.

[0013] When heat user i supplied by the i-th stage flash tank is stopped, liquid heat transfer oil is supplied to the i+1-th stage flash tank through a branch pipeline.

[0014] When the load required by the heat user i+1 is greater than the load required by the heat user i, the output flow of the heat transfer oil circulation pump connected to the i-stage flash tank through the i-stage circulation pipeline is greater than the flow entering the i+1-stage flash tank. When the steam flow in the i+1-stage flash tank needs to be changed, the regulating valve connected to the i-stage circulation pipeline is controlled to change the liquid-phase heat transfer oil flow entering the i+1-stage flash tank to achieve the change.

[0015] The final stage circulation pipeline is only connected with a heat transfer oil circulation pump.

[0016] The pipeline system connected to the i-th stage flash tank has ni sets.

[0017] In summary, this application at least includes the following beneficial technical effects:

[0018] A thermal oil furnace is used for heating, and through multi-stage flash evaporation, gas phase thermal oil of different temperatures is produced to supply heat users. At the same time, the output of gas phase thermal oil of each temperature is controlled stably. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the process of producing multi-temperature gas-phase heat transfer oil by using a single heat transfer oil furnace + multi-stage flash evaporation method as described in the invention.

[0020] Figure 2 Schematic diagram of a process with three flash tanks.

[0021] Explanation of the accompanying figures: 1-thermal oil furnace, 2-flash tank I, 3-condensate tank I, 4-thermal oil condensate pump I, 5-thermal oil circulation pump I, 6-flash tank II, 7-condensate tank II, 8-thermal oil condensate pump II, 9-thermal oil circulation pump II, 10-pressure reducing valve I, 11-pressure reducing valve II, 12-regulating valve. DETAILED DESCRIPTION

[0022] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments disclosed in the present invention will be further described in detail below with reference to the accompanying drawings.

[0023] The present application discloses a thermal oil flash evaporation system, which uses a single thermal oil furnace + multi-stage flash evaporation method to produce multi-temperature gas-phase thermal oil, such as Figure 1 As shown, it includes a thermal oil furnace 1, a flash tank I2, a condensate tank I3, a thermal oil condensate pump I4, a thermal oil circulation pump I5, a flash tank II6, a condensate tank II7, a thermal oil condensate pump II8 and a thermal oil circulation pump II9.

[0024] The outlet of the thermal oil furnace 1 is connected to the flash tank I2 through a liquid inlet pipeline. The gaseous thermal oil produced by the flash tank I2 is used to heat the heat user 1 and then becomes liquid-phase thermal oil and returns to the flash tank I2. The gaseous thermal oil produced by the flash tank II6 is used to heat the heat user 2 and then becomes liquid-phase thermal oil and returns to the flash tank II6. The flash tank I2 is connected to the thermal oil furnace 1 through a first circulation pipeline. Along the flow direction of the thermal oil in the first circulation pipeline, the first circulation pipeline is sequentially connected with a thermal oil circulation pump. I5 and regulating valve 12, regulating valve 12 is used to control the flow rate of high-temperature heat-conducting oil entering the heat-conducting oil furnace 1, the first circulation pipeline is connected to the flash tank II6 through the second-level liquid inlet pipeline, and the pipeline connection point between the second-level liquid inlet pipeline and the first circulation pipeline is located between the heat-conducting oil circulation pump I5 and the regulating valve 12; the flash tank II6 is connected to the heat-conducting oil furnace 1 through the second circulation pipeline, and the second circulation pipeline is connected to the heat-conducting oil circulation pump II9; the liquid inlet pipeline is connected to the flash tank II6 through a branch pipeline.

[0025] The flash tank I2 is connected to the heat user 1 through the first gas outlet pipeline, the heat user 1 is connected to the condensate tank I3 through the first liquid return pipeline, the condensate tank I3 is connected to the flash tank I2 through the first condensation pipeline, and the first condensation pipeline is connected to a heat transfer oil condensate pump I4.

[0026] The flash tank II6 is connected to the heat user 2 through the second gas outlet pipeline, the heat user 2 is connected to the condensate tank II7 through the second liquid return pipeline, the condensate tank II7 is connected to the flash tank II6 through the second condensation pipeline, and a heat transfer oil condensate pump II8 is arranged on the second condensation pipeline.

[0027] The liquid inlet pipeline is connected with a pressure reducing valve I10, and the second-stage liquid inlet pipeline is connected with a pressure reducing valve II11.

[0028] The other end of the branch pipeline is connected to the second-level liquid inlet pipeline. Along the flow direction of the liquid heat transfer oil in the second-level liquid inlet pipeline, the connection point between the branch pipeline and the second-level liquid inlet pipeline and the pressure reducing valve II11 are distributed in sequence on the second-level liquid inlet pipeline.

[0029] After the low-temperature liquid phase heat transfer oil is heated and heated under a certain pressure in the heat transfer oil furnace 1, it is decompressed by the pressure reducing valve I10, and the pressure of the heat transfer oil is lower than its saturated pressure, and then enters the flash tank I2. The high-temperature liquid phase heat transfer oil is partially flash vaporized in the flash tank I2 to form a gas phase heat transfer oil of the corresponding temperature. The gas phase heat transfer oil is transported to the heat user I through a pipeline in a natural circulation manner, and after releasing the latent heat in the heat user I, it forms a saturated liquid phase heat transfer oil and is collected in the condensate tank I3, and then transported to the flash tank I2 through the heat transfer oil condensate pump I4 at the bottom of the condensate tank I3. The liquid phase heat transfer oil in the flash tank I2 is transported to the flash tank II6 through the heat transfer oil circulation pump I5 at the bottom of the tank, and the other part is sent back to the heat transfer oil furnace 1 to complete reheating. The liquid phase heat transfer oil sent to the flash tank II6 is saturated heat transfer oil. After being depressurized by the pressure reducing valve II11, it enters the flash tank II6 to complete the phase transition and forms another low-temperature gas phase heat transfer oil. This low-temperature gas phase heat transfer oil is transported to the heat user II through a pipeline, and after releasing latent heat in the heat user II, it forms a saturated liquid phase heat transfer oil and enters the condensate tank II7, and then is transported to the flash tank II6 through the heat transfer oil condensate pump II8 at the bottom of the condensate tank II7. Part of the heat transfer oil in the flash tank II6 is transported back to the heat transfer oil furnace 1 through the heat transfer oil circulation pump II9 for reheating, completing the entire circulation process.

[0030] Among them, the pressure in flash tank I is achieved by controlling the outlet temperature of the thermal oil of the thermal oil furnace; the pressure in flash tank II is achieved by controlling the flow rate entering flash tank II.

[0031] The heat transfer oil after heating in the heat transfer oil furnace 1 is in liquid phase, and its temperature is higher than the steam temperature generated in the flash tank 12. When the steam flow in the flash tank 12 needs to change, it is achieved by changing the outlet heat transfer oil temperature of the heat transfer oil furnace.

[0032] When the load required by heat user II is greater than the load required by heat user I, the circulation volume of the thermal oil furnace 1 must meet the flow requirements of the flash tank I2 and the flash tank II6, that is, the output flow of the thermal oil circulation pump I5 must always be greater than the flow entering the flash tank II6; when the steam flow in the flash tank II6 needs to change, it can be achieved by controlling the regulating valve 12 to change the flow of the liquid phase thermal oil entering the flash tank II6.

[0033] At the same time, in order to ensure that heat user II can still be used when heat user I is deactivated, a branch pipeline is set at the outlet of the thermal oil furnace 1 to directly connect to the second-level liquid inlet pipeline connected to the flash tank II6, and the pipeline connection point is before the pressure reducing valve II11. When heat user I is deactivated, the flash evaporation requirements of the flash tank II6 can be directly achieved by controlling the outlet temperature of the thermal oil furnace 1 to meet the gas phase thermal oil demand of heat user II.

[0034] In summary, the idea of ​​the present invention is that the entire system is equipped with only one thermal oil furnace, and the heat provided by the furnace can generate gas-phase thermal oil at different temperatures through a multi-stage flash tank. At the same time, the gas-phase thermal oil at each temperature can be subjected to certain load adjustment through different control means, and can be realized without affecting each other, so as to meet the different heat requirements of users and realize load adjustment.

[0035] The above description introduces the flash evaporation of thermal oil in series with two temperature levels. This patent can be extended to more stages of flash evaporation systems in series. For example, when there is a third stage flash tank, such as Figure 2 shown.

[0036] This patent proposes a thermal oil flash evaporation system and process, which adopts a multi-stage flash evaporation method and a design of a thermal oil furnace + multiple flash tanks in series. The high-temperature liquid phase thermal oil output by the thermal oil furnace is used to produce multi-temperature gas phase thermal oil output through multi-stage flash evaporation to meet the different needs of heat users.

[0037] The contents not described in detail in this application specification belong to the common knowledge of those skilled in the art.

[0038] The present application is described in detail above in conjunction with specific implementation methods and exemplary examples, but these descriptions cannot be understood as limiting the present application. Those skilled in the art understand that, without departing from the spirit and scope of the present application, a variety of equivalent replacements, modifications or improvements can be made to the technical solution of the present application and its implementation methods, all of which fall within the scope of the present application. The scope of protection of the present application shall be subject to the attached claims.

Claims

1. A thermal oil flash evaporation system, characterized in that: The invention comprises a heat transfer oil furnace (1) and an n-stage flash tank, wherein n is an integer greater than 1, and the flash tanks are respectively converted into liquid heat transfer oil after supplying heat to different heat users and return to the flash tanks, and the n-stage flash tanks include an i-th stage flash tank and an n-th stage flash tank, i+1≤n, and the outlet of the heat transfer oil furnace (1) is connected to the i-th stage flash tank and the n-th stage flash tank through a liquid inlet pipeline, and the i-th stage flash tank is connected to a pipeline system for supplying liquid heat transfer oil to the subsequent flash tank and the heat transfer oil furnace (1), and the pipeline system includes an i-th stage circulating A ring pipeline and an i+1-stage liquid inlet pipeline, the i-stage flash tank is connected to a thermal oil furnace (1) via the i-stage circulation pipeline, a thermal oil circulation pump and a regulating valve are sequentially connected to the i-stage circulation pipeline along the flow direction of the thermal oil in the i-stage circulation pipeline, the regulating valve is used to control the flow rate of the thermal oil, the i-stage circulation pipeline is connected to the i+1-stage flash tank via the i+1-stage liquid inlet pipeline, and the pipeline connection point between the i+1-stage liquid inlet pipeline and the circulation pipeline is located between the thermal oil circulation pump and the regulating valve; The nth-stage flash tank is connected to the heat transfer oil furnace (1) through the final i-stage circulation pipeline.

2. A thermal oil flash evaporation system according to claim 1, characterized in that: The j-th flash tank is connected to heat user j through an outlet pipeline, j∈[1-n], heat user j is connected to a condensate tank through a liquid return pipeline, and the condensate tank is connected to the j-th flash tank through a condensation pipeline.

3. A thermal oil flash evaporation system according to claim 1, characterized in that: The condensation pipeline is connected with a heat transfer oil condensate pump.

4. A thermal oil flash evaporation system according to claim 1, characterized in that: The liquid inlet pipeline is also connected to a branch pipeline, one end of the branch pipeline is connected to the liquid inlet pipeline, and the other end is connected to other flash tanks, the other flash tanks are x-th flash tanks, x∈[1, n] and x≠i, and the other end of the branch pipeline is specifically connected between the heat transfer oil circulation pump and the regulating valve on the x-th liquid inlet pipeline connected to the x-th flash tank.

5. A thermal oil flash evaporation system according to claim 4, characterized in that: The liquid inlet pipeline and the (i+1)th level liquid inlet pipeline are both provided with pressure reducing valves.

6. A thermal oil flash evaporation system according to claim 5, characterized in that: The position of the pressure reducing valve connected on the liquid inlet pipeline is: along the flow direction of the liquid-phase heat transfer oil in the liquid inlet pipeline, the connection point between the branch pipeline and the liquid inlet pipeline, and the pressure reducing valve are distributed on the liquid inlet pipeline in sequence; the position of the pressure reducing valve connected on the x-th level liquid inlet pipeline is: along the flow direction of the liquid-phase heat transfer oil in the x-th level liquid inlet pipeline, the connection point between the branch pipeline and the x-th level liquid inlet pipeline, and the pressure reducing valve are distributed on the x-th level liquid inlet pipeline in sequence.

7. A thermal oil flash evaporation system according to claim 4, characterized in that: When heat user i supplied by the i-th stage flash tank is stopped, liquid heat transfer oil is supplied to the i+1-th stage flash tank through a branch pipeline.

8. A thermal oil flash evaporation system according to claim 1, characterized in that: When the load required by the heat user i+1 is greater than the load required by the heat user i, the output flow of the heat transfer oil circulation pump connected to the i-stage flash tank through the i-stage circulation pipeline is greater than the flow entering the i+1-stage flash tank. When the steam flow in the i+1-stage flash tank needs to be changed, the regulating valve connected to the i-stage circulation pipeline is controlled to change the liquid-phase heat transfer oil flow entering the i+1-stage flash tank to achieve the change.

9. A thermal oil flash evaporation system according to claim 1, characterized in that: The final stage circulation pipeline is only connected with a heat transfer oil circulation pump.

10. A thermal oil flash evaporation system according to claim 1, characterized in that: The pipeline system connected to the i-th stage flash tank has ni sets.

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