Low-boiling-point substance collecting device of heat conduction oil heating furnace

Abstract

The utility model discloses a low-boiling-point substance collecting device of a heat conduction oil heating furnace. The low-boiling-point substance collecting device comprises an expansion tank and an oil-gas separator, the oil-gas separator is in fluid communication with an inner cavity of the expansion tank through an expansion pipeline, an exhaust port is formed in the top of the expansion tank, the low-boiling-point substance ascending pipe is in fluid communication with the inner cavity of the expansion tank through the exhaust port, and the condensate descending pipe and the low-boiling-point substance ascending pipe are arranged at intervals; the condensing pipes are arranged between the low-boiling-point substance ascending pipe and the condensate descending pipe, each condensing pipe is obliquely arranged from the low-boiling-point substance ascending pipe to the condensate descending pipe from high to low, and the low-boiling-point substance ascending pipe, the condensing pipes and the condensate descending pipe are in fluid communication. The device further comprises a low-boiling-point substance condensate recovery tank, and the condensate descending pipe is communicated with the low-boiling-point substance condensate recovery tank through a condensate recovery pipeline. Low-boiling-point substances are continuously and rapidly collected on line, the heat transfer performance of heat conduction oil is improved, the heating furnace operates stably, and the heat efficiency is high.

Description

Technical Field

[0001] This utility model relates to a thermal oil heater for heat exchange, and more particularly to a low-boiling-point collection device for a thermal oil heater, belonging to the field of heater technology. Background Technology

[0002] The thermal oil heater includes an expansion tank, an oil-gas separator located below the expansion tank, a thermal oil circulation pump, a main circulation pipeline system, a furnace body, and heating pipes installed inside the furnace body. The oil-gas separator is fluidly connected to the inner cavity of the expansion tank through an expansion pipe. The oil inlet and outlet of the thermal oil circulation pump are connected to the oil-gas separator and the heating pipes respectively through the main circulation pipeline. During the operation of the thermal oil heater, the return oil from each heat-using unit of the process unit enters the oil-gas separator through the main circulation pipeline. The oil-gas separator separates and precipitates low-boiling-point substances, non-condensable vapors, and other gaseous components from the return oil. After that, the oil enters the expansion tank through the expansion pipeline. Because the temperature of the thermal oil in the expansion tank is relatively low, and the top of the expansion tank is sealed with nitrogen micro-positive pressure, some of the separated low-boiling-point substances and non-condensable vapors adhere to the inner wall of the top of the expansion tank and cool to form low-boiling-point substance condensate. This condensate slowly drips back into the thermal oil in the expansion tank. The low-boiling-point substances are composed of low molecular weight aromatic hydrocarbons, alkanes, etc., among which the more abundant ones are toluene, cyclohexane, cyclopentylbenzene, ethylbenzene, cyclohexylbenzene, etc. The main organic matter content is about 70%. Because the expansion pipeline of the expansion tank has the function of connecting the upper and lower parts, the thermal oil in the expansion pipeline heats up and cools down, causing the low-boiling-point substance condensate to flow back into the main circulation pipeline system. Thus, on the one hand, as the service life of the heat transfer oil increases, the increased low-boiling-point condensate gradually reduces its thermal conductivity, leading to increased load on the heat transfer oil heater, reduced thermal efficiency, and fluctuations in the reaction temperature of the heat-using unit, fluctuations in the inlet pressure of the heat transfer oil circulating pump, and unstable pressure in the main circulation pipeline system, all of which affect the stable operation of the heat transfer oil heater. On the other hand, excessive low-boiling-point condensate in the main circulation pipeline system will locally vaporize and form vapor locks, affecting the flow state of the heat transfer oil, causing slow local flow and resulting in local overheating. This vicious cycle further increases the low-boiling-point content in the heat transfer oil, and long-term accumulation leads to changes in the physical properties of the heat transfer oil. Summary of the Invention

[0003] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a low-boiling-point collection device for a heat transfer oil heater that can continuously and rapidly collect low-boiling-point substances during the operation of the heat transfer oil heater and prevent the low-boiling-point substance condensate from flowing back into the main circulation pipeline system.

[0004] To solve the above-mentioned technical problems, this utility model adopts a low-boiling-point substance collection device for a heat transfer oil heater, including an expansion tank and an oil-gas separator disposed below the expansion tank; the oil-gas separator is fluidly connected to the inner cavity of the expansion tank through an expansion pipe, and also includes a low-boiling-point substance riser, several condenser pipes, and a condensate downcomer. An exhaust port is provided at the top of the expansion tank, the low-boiling-point substance riser is disposed above the expansion tank, and the low-boiling-point substance riser is fluidly connected to the inner cavity of the expansion tank through the exhaust port. The condensate downcomer is arranged alternately with the low-boiling-point substance riser, and the several condenser pipes are disposed between the low-boiling-point substance riser and the condensate downcomer, with each condenser pipe inclined from high to low from the low-boiling-point substance riser to the condensate downcomer. The low-boiling-point substance riser, the several condenser pipes, and the condensate downcomer are fluidly connected.

[0005] In a preferred embodiment of this utility model, a low-boiling-point condensate recovery tank is also included, wherein the condensate downcomer is connected to the low-boiling-point condensate recovery tank via a condensate recovery pipe.

[0006] In a preferred embodiment of this utility model, heat dissipation fins are also provided on the outer wall of each condenser tube.

[0007] In a preferred embodiment of this utility model, a cooling fan is provided on one side of the condensate downcomer.

[0008] In a preferred embodiment of this utility model, the expansion tank is equipped with a pressure sensor for measuring the gas pressure inside the expansion tank, and the cooling fan, the pressure sensor and the central controller of the heat transfer oil heating furnace are connected.

[0009] In a preferred embodiment of this utility model, the low-boiling-point riser and the condensate downcomer are both arranged vertically. The low-boiling-point riser is closed at the top and open at the bottom. The lower end of the low-boiling-point riser is connected to the exhaust port. The condensate downcomer is open at the top and has a tapered opening at the bottom. A flame arrestor breather valve is installed at the top of the condensate downcomer.

[0010] By adopting the above structure, this utility model has the following beneficial effects:

[0011] Because this utility model is equipped with a low-boiling-point riser, several condenser pipes and a condensate downcomer, and an exhaust port is provided at the top of the expansion tank, the low-boiling-point riser is fluidly connected to the inner cavity of the expansion tank through the exhaust port, the condenser pipes are arranged between the low-boiling-point riser and the condensate downcomer, and each condenser pipe is inclined from high to low from the low-boiling-point riser to the condensate downcomer, and the low-boiling-point riser, condenser pipes and condensate downcomer are fluidly connected. During the operation of the thermal oil heater, the return oil from each heat-using unit of the process unit enters the oil-gas separator through the main circulation pipeline. The oil-gas separator separates and precipitates low-boiling-point substances, non-condensable vapors, and other gaseous components from the return oil. The oil then enters the expansion tank through the expansion pipeline and is discharged through the exhaust port at the top of the expansion tank to the low-boiling-point substance riser pipe. It then enters the condenser pipe, where the low-boiling-point substances are cooled and condensed into condensate. The condensate in each condenser pipe flows into the condensate downcomer pipe along the pipe slope and is then discharged. Therefore, this invention effectively prevents the low-boiling-point substance condensate from flowing back into the main circulation pipeline system by continuously and rapidly collecting low-boiling-point substances. In addition, this invention preferably recovers the low-boiling-point substance condensate by entering the low-boiling-point substance condensate recovery tank through the condensate recovery pipeline. This structure allows for the comprehensive and environmentally friendly treatment and recovery of oil containing low-boiling-point substances, effectively reducing the pollution caused by the direct discharge of low-boiling-point substances into the air, while avoiding the problem of regenerating and purifying the total oil volume of the heater.

[0012] This invention also provides heat dissipation fins on the outer wall of each condenser tube. This structure facilitates the rapid cooling of low-boiling substances into condensate after they enter the condenser tube.

[0013] This invention features a cooling fan on one side of the condensate downcomer. This structure further accelerates and efficiently cools low-boiling-point substances into condensate after they enter the condenser, greatly improving the recovery efficiency of low-boiling-point substances. It also helps to reduce the gas pressure in the expansion tank.

[0014] The cooling fan and pressure sensor of this invention are connected to the central controller of the thermal oil heater. When the gas pressure in the expansion tank is higher than the set pressure value, the central controller controls the cooling fan to turn on automatically, so that the gas pressure in the expansion tank is lower than or equal to the set pressure value.

[0015] In this invention, both the low-boiling-point riser and the condensate downcomer are arranged vertically. The low-boiling-point riser is closed at the top and open at the bottom, with its lower end connected to the exhaust port. The condensate downcomer is open at the top and has a tapered opening at the bottom. This structure is simple and easy to implement. Furthermore, the tapered opening at the bottom of the condensate downcomer allows for connection to smaller diameter pipes, facilitating the laying of pipes and connection to the low-boiling-point condensate recovery tank.

[0016] This invention significantly improves the heat transfer performance of heat transfer oil by collecting low-boiling-point substances online, resulting in stable furnace operation and smooth adjustment of the regulating valve opening and precise temperature control in the main circulation pipeline system. Attached Figure Description

[0017] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings.

[0018] Figure 1 This is a schematic diagram of a low-boiling-point substance collection device for a thermal oil heater according to this utility model.

[0019] Figure 2 This is a schematic diagram of a connection structure of the expansion tank, the low-boiling-point riser, the condenser, and the condensate downcomer in this utility model. Detailed Implementation

[0020] See Figure 1 , 2 The diagram illustrates a low-boiling-point collection device for a thermal oil heater, comprising an expansion tank 1 and an oil-gas separator 2 disposed below the expansion tank 1. The oil-gas separator 2 is fluidly connected to the inner cavity of the expansion tank 1 via an expansion pipe 3. It also includes a low-boiling-point riser pipe 4, several condenser pipes 5, and a condensate downcomer pipe 6. The several condenser pipes 5 refer to at least one; the diagram shows seven, but there can be more or fewer. An exhaust port 1-1 is provided at the top of the expansion tank 1. The exhaust port 1-1 is preferably large-diameter, with a diameter of 25-40 mm. Between 0mm and 0mm, the low-boiling-point riser 4 is positioned above the expansion tank 1, and the low-boiling-point riser 4 is fluidly connected to the inner cavity of the expansion tank 1 through the exhaust port 1-1. The condensate downcomer 6 is arranged at intervals with the low-boiling-point riser 4. Several condenser pipes 5 are positioned between the low-boiling-point riser 4 and the condensate downcomer 6, and each condenser pipe 5 is inclined from high to low from the low-boiling-point riser 4 to the condensate downcomer 6. The low-boiling-point riser 4, the several condenser pipes 5, and the condensate downcomer 6 are fluidly connected.

[0021] As a preferred embodiment of this utility model, such as Figure 1 As shown, it also includes a low-boiling-point condensate recovery tank 7, and the condensate downcomer 6 is connected to the low-boiling-point condensate recovery tank 7 through a condensate recovery pipe 8.

[0022] As a preferred embodiment of this utility model, such as Figure 1 , 2 As shown, each condenser tube 5 is also provided with heat dissipation fins 9 on its outer wall.

[0023] As a preferred embodiment of this utility model, such as Figure 1 , 2As shown, a cooling fan 10 is provided on one side of the condensate downcomer 6.

[0024] In a preferred embodiment of this utility model, the expansion tank 1 is equipped with a pressure sensor for measuring the air pressure inside the expansion tank. The cooling fan 10, the pressure sensor, and the central controller of the heat transfer oil heater are connected via wired cable or wireless signal. The central controller can be a programmable logic controller (PLC), a distributed control system (DCS), or an industrial computer. The pressure sensor and the central controller are not shown in the figure.

[0025] As a preferred embodiment of this utility model, such as Figure 1 , 2 As shown, both the low-boiling-point riser 4 and the condensate downcomer 6 are vertically arranged and cylindrical. The low-boiling-point riser 4 is closed at the top and open at the bottom, with its lower end connected to the exhaust port 1-1. The condensate downcomer 6 is open at the top and has a tapered opening 6a at the bottom. A flame arrestor breather valve 11 is installed at the top of the condensate downcomer 6. The tapered opening 6a at the bottom of the condensate downcomer 6 is connected to a smaller diameter pipe, shown in the figure, which is the condensate recovery pipe 8, facilitating the laying of pipes and connection to the low-boiling-point condensate recovery tank 7. In this invention, the low-boiling-point riser 4 and the condensate downcomer 6 can also be arranged horizontally with varying heights, as shown in the figure.

[0026] See Figure 1 The thermal oil heating furnace includes an expansion tank 1, an oil-gas separator 2 located below the expansion tank 1, a thermal oil circulation pump 12, a main circulation pipeline system, a furnace body, and heating pipes installed in the furnace body, an oil storage tank 14, a make-up oil pump 15, etc. The main circulation pipeline system includes a main circulation pipeline 13 and regulating valves, etc. The furnace body and the heating pipes installed in the furnace body are not shown in the figure. In a preferred embodiment of this utility model, during the operation of the thermal oil heater, the return oil from each heat-using unit of the process unit enters the oil-gas separator 2 through the main circulation pipeline 13. After the oil-gas separator 2 separates and precipitates low-boiling matter, non-condensable vapor and other gas components from the return oil, it enters the expansion tank 1 through the expansion pipeline 3, and is discharged to the low-boiling matter riser pipe 4 through the exhaust port 1-1 at the top of the expansion tank 1, and then enters the condenser pipe 5. After entering the condenser pipe 5, the low-boiling matter dissipates heat and cools into condensate. The condensate in each condenser pipe 5 flows into the condensate downcomer pipe 6 with the slope of the pipeline, and then enters the low-boiling matter condensate recovery tank 7 through the condensate recovery pipeline 8 for recovery.

[0027] After trial use, this utility model has proven to be effective in continuously and rapidly collecting low-boiling-point substances online, preventing the condensate from flowing back into the main circulation pipeline system, improving the heat transfer performance of the heat transfer oil, ensuring stable operation of the heating furnace, and achieving high thermal efficiency. It is a beneficial measure for energy conservation and emission reduction in industrial boilers and has achieved good practical results.

Claims

1. A low-boiling-point collection device for a thermal oil heater, comprising an expansion tank (1) and an oil-gas separator (2) disposed below the expansion tank (1); the oil-gas separator (2) is fluidly connected to the inner cavity of the expansion tank (1) via an expansion pipe (3), characterized in that: It also includes a low-boiling-point riser (4), several condenser pipes (5) and a condensate downcomer (6). The expansion tank (1) has an exhaust port (1-1) at the top. The low-boiling-point riser (4) is located above the expansion tank (1) and is fluidly connected to the inner cavity of the expansion tank (1) through the exhaust port (1-1). The condensate downcomer (6) is arranged at intervals with the low-boiling-point riser (4). Several condenser pipes (5) are arranged between the low-boiling-point riser (4) and the condensate downcomer (6). Each condenser pipe (5) is inclined from the low-boiling-point riser (4) to the condensate downcomer (6) from high to low. The low-boiling-point riser (4), several condenser pipes (5) and condensate downcomer (6) are fluidly connected.

2. The low-boiling-point substance collection device for a thermal oil heater according to claim 1, characterized in that: It also includes a low-boiling-point condensate recovery tank (7), and the condensate downcomer (6) is connected to the low-boiling-point condensate recovery tank (7) through a condensate recovery pipe (8).

3. The low-boiling-point substance collection device for a thermal oil heater according to claim 1, characterized in that: Each condenser tube (5) is also provided with heat dissipation fins (9) on its outer wall.

4. The low-boiling-point substance collection device for a thermal oil heater according to claim 1, characterized in that: A cooling fan (10) is provided on one side of the condensate downcomer (6).

5. The low-boiling-point substance collection device for a thermal oil heater according to claim 4, characterized in that: The expansion tank (1) is equipped with a pressure sensor for measuring the gas pressure inside the expansion tank. The cooling fan (10) and the pressure sensor are connected to the central controller of the heat transfer oil heater.

6. The low-boiling-point substance collection device for a thermal oil heater according to any one of claims 1 to 5, characterized in that: The low-boiling-point riser (4) and the condensate downcomer (6) are both arranged vertically. The low-boiling-point riser (4) is closed at the top and open at the bottom. The lower end of the low-boiling-point riser (4) is connected to the exhaust port (1-1). The condensate downcomer (6) is open at the top and is a conical open pipe (6a) at the bottom. A flame arrestor breather valve (11) is installed at the upper end of the condensate downcomer (6).

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