An online solid impurity cleaning device for highly corrosive materials

Abstract

This invention provides an online solid impurity cleaning device for highly corrosive materials, relating to the fields of chemical engineering and industrial equipment technology. The device includes a high-boiling-point storage tank, a high-pressure pump, a filter, pipelines, a heating system, a flushing liquid collection tank, and a control system. The high-boiling-point storage tank stores the high-boiling-point substances separated by distillation from the reaction products of the highly corrosive materials. The high-pressure pump pressurizes the high-boiling-point substances into a high-pressure flushing liquid. The heating system (electric or steam heating) on ​​the pipelines maintains the temperature of the high-boiling-point substances to preserve their solubility. The filter traps impurities, and after flushing, the impurities and high-boiling-point substances are discharged into the collection tank. The device can clean online without disassembling the filter. The control system controls the start / stop of the high-pressure pump, the pressure, and the heating power. It is suitable for materials containing fluorine-chlorine exchange byproduct impurities in the production of 1,1,1,3,3-pentafluoropropane, solving the problems of high raw material flushing consumption and poor low-temperature cleaning effect in existing methods, thus improving cleaning efficiency and safety.

Description

Technical Field

[0001] This utility model relates to the field of chemical engineering and industrial equipment technology, and in particular to an online solid impurity cleaning device for highly corrosive materials. Background Technology

[0002] In the fluorochemical field, 1,1,1,3,3-pentafluoropropane (HFC-245fa), an environmentally friendly blowing agent with zero ozone depletion potential (ODP) and low global warming potential (GWP), has been widely used in the production of rigid polyurethane foam. Its mainstream industrial production route involves a fluorine-chlorine exchange reaction between 1,1,1,3,3-pentachloropropane (240fa) and anhydrous hydrogen fluoride (HF). During this reaction, side reactions inevitably occur, generating a certain amount of high-molecular-weight solid impurities.

[0003] As the production unit operates continuously, these solid impurities will accumulate in the reactor, distillation column, reboiler and connected pipelines, causing equipment and pipeline blockage, reduced heat transfer efficiency, and ultimately seriously affecting the long-term, stable and safe operation of the production unit.

[0004] Currently, the industry standard for handling solid impurities in such highly hazardous and corrosive materials is to install filters on process pipelines to intercept them. When the pressure difference across the filter increases to a set value, operators switch to a parallel standby filter. The filter with trapped solid impurities needs to undergo pretreatment steps such as nitrogen purging and solvent washing to remove residual highly corrosive and hazardous materials (such as HF). Only after pretreatment can the filter be disassembled, and the filter element removed for offline manual cleaning. Alternatively, an online cleaning method exists, which involves using backwash liquid to reverse-flush the filter element, dispersing the solid impurities before discharging them into a collection system.

[0005] Existing technologies typically use relatively mild chemical raw materials (such as 240fa) as backwashing fluids. This method primarily relies on the high-pressure flushing force of the fluid to remove impurities, and to some extent utilizes the compatibility between the fluid and the impurities for dissolution. However, this method has significant drawbacks: First, using raw materials as the flushing fluid directly leads to the consumption of valuable raw materials, increasing production costs; second, the flushing effect is greatly affected by ambient temperature, especially at low temperatures, where the solubility of the flushing fluid for solid impurities decreases sharply, resulting in incomplete flushing, low efficiency, and even potential secondary blockage due to impurity re-precipitation.

[0006] Therefore, there is an urgent need to develop an efficient, economical, safe and reliable online processing technology and device to solve the problem of cleaning solid impurities in highly hazardous and corrosive materials. Utility Model Content

[0007] Therefore, the technical problem to be solved by this utility model is to overcome the problems of high consumption and poor cleaning effect in low temperature environment caused by using raw materials as rinsing liquid in the prior art.

[0008] To solve the above-mentioned technical problems, this utility model provides an online solid impurity cleaning device for highly corrosive materials. The device includes: a high-boiling-point storage tank, a high-pressure pump, a filter, pipelines, a heating system, and a flushing liquid collection tank. The outlet of the high-boiling-point storage tank is connected to the inlet of the high-pressure pump via a pipeline. The outlet of the high-pressure pump is connected to the inlet of the filter via a pipeline. The outlet of the filter is connected to the flushing liquid collection tank via a pipeline. A heating system is installed on the pipeline between the high-boiling-point storage tank and the filter, and a valve for controlling the pipeline's on / off state is also installed on the pipeline. The filter is used to trap solid impurities in the highly corrosive materials. The high-pressure pump is used to pressurize the high-boiling-point substances in the high-boiling-point storage tank to form a high-pressure flushing liquid to flush away the solid impurities trapped by the filter. The flushed solid impurities are discharged into the flushing liquid collection tank along with the high-boiling-point substances.

[0009] In one embodiment of this utility model, the heat tracing system is an electric heat tracing system or a steam heat tracing system.

[0010] In one embodiment of this utility model, the high-boiling-point substances stored in the high-boiling-point substance storage tank are derived from the high-boiling-point substances obtained after separation by a subsequent distillation unit from the reaction products of highly corrosive materials.

[0011] In one embodiment of this utility model, the boosting pressure of the high-pressure pump is adjustable, and the pressure of the boosted high-pressure flushing fluid can meet the flushing requirements of solid impurities trapped in the filter.

[0012] In one embodiment of this utility model, the valve includes a first valve and a second valve; the first valve is disposed on the pipeline between the outlet of the high-pressure pump and the inlet of the filter, and is used to control the flow of high-pressure flushing fluid into the filter; the second valve is disposed on the pipeline between the outlet of the filter and the flushing fluid collection tank, and is used to control the flow of the mixture of solid impurities and high-boiling substances after flushing into the flushing fluid collection tank.

[0013] In one embodiment of this utility model, the highly corrosive material is a material containing solid impurities generated during the production of 1,1,1,3,3-pentafluoropropane; the solid impurities are byproducts generated during the fluorine-chlorine exchange reaction between 1,1,1,3,3-pentachloropropane and anhydrous hydrogen fluoride.

[0014] In one embodiment of this utility model, the device can achieve online cleaning of solid impurities without disassembling the filter. By flushing the filter with high-pressure flushing fluid, the solid impurities are directly discharged into the flushing fluid collection tank along with the high-boiling-point substances, avoiding the need for offline cleaning of the filter.

[0015] In one embodiment of this utility model, before the filter is subjected to high-pressure rinsing, a pretreatment process is required to replace the residual highly corrosive materials inside; after the pretreatment is completed, a high-pressure rinsing liquid is delivered by a high-pressure pump to clean the solid impurities.

[0016] In one embodiment of the present invention, the device further includes a control system, which is electrically connected to the high-pressure pump and the heat tracing system respectively; the control system is used to control the start and stop of the high-pressure pump and its output pressure, and at the same time to adjust the heating power of the heat tracing system.

[0017] In one embodiment of this utility model, the heat tracing system includes a temperature sensor and a temperature controller; the temperature sensor is attached to the pipeline and is used to detect the temperature of the high-boiling substance in the pipeline in real time and transmit the temperature signal to the temperature controller; the temperature controller is electrically connected to the heating element of the heat tracing system and is used to adjust the power of the heating element according to the detection signal of the temperature sensor, so that the temperature of the high-boiling substance in the pipeline is stabilized within a preset temperature range.

[0018] Compared with the prior art, the above-mentioned technical solution of this utility model has the following beneficial effects: (1) Reduce raw material consumption and realize resource recycling: Use the high-boiling point of the reaction product of high-risk corrosive materials after distillation separation as high-pressure flushing liquid to replace the valuable raw materials (such as 240fa) in the existing technology, reduce raw material loss, and realize the reuse of waste by-products (high-boiling point) to reduce production costs.

[0019] (2) Ensure the cleaning effect in low temperature environment: By setting an electric heating or steam heating system on the pipeline between the high boiling point storage tank and the filter, and by adjusting the heating power in real time with the temperature sensor and temperature controller, the temperature of the high boiling point is stabilized in the preset range, avoiding the problem of the high boiling point reducing the solubility of solid impurities due to low temperature, ensuring thorough rinsing and preventing secondary blockage.

[0020] (3) Improve cleaning safety and efficiency: The device can achieve online cleaning without disassembling the filter. After rinsing, solid impurities are directly discharged into the collection tank along with high-boiling-point substances, avoiding the tedious operation of disassembly after shutdown. In addition, the filter is pre-treated before rinsing to replace residual high-risk corrosive materials, reducing safety risks and reducing downtime of production equipment, thus improving overall operating efficiency. Attached Figure Description

[0021] To make the content of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein: Figure 1 This is a schematic diagram of the structure of an online solid impurity cleaning device for highly corrosive materials provided by this utility model.

[0022] Explanation of the reference numerals in the accompanying drawings: 1. High boiling point storage tank; 2. High pressure pump; 3. First valve; 4. Filter; 5. Second valve; 6. Rinse fluid collection tank; 7. Heating system. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments are not intended to limit the present invention.

[0024] Example 1: To address the problems of high consumption and poor cleaning effect at low temperatures caused by using raw materials as rinsing fluid in existing technologies. (Refer to...) Figure 1 As shown, this utility model provides an online solid impurity cleaning device for highly corrosive materials. The device includes: a high-boiling-point storage tank 1, a high-pressure pump 2, a filter 4, pipelines, a heating system 7, and a flushing liquid collection tank 6. The outlet of the high-boiling-point storage tank 1 is connected to the inlet of the high-pressure pump 2 via a pipeline. The outlet of the high-pressure pump 2 is connected to the inlet of the filter 4 via a pipeline. The outlet of the filter 4 is connected to the flushing liquid collection tank 6 via a pipeline. A heating system 7 is installed on the pipeline between the high-boiling-point storage tank 1 and the filter 4, and a valve for controlling the pipeline's on / off state is also installed on the pipeline. The filter 4 is used to trap solid impurities in the highly corrosive materials. The high-pressure pump 2 is used to pressurize the high-boiling-point substances in the high-boiling-point storage tank 1 to form a high-pressure flushing liquid to flush the solid impurities trapped by the filter 4. The flushed solid impurities and high-boiling-point substances are discharged together into the flushing liquid collection tank 6.

[0025] As can be seen from the above technical solution, this utility model proposes an online solid impurity cleaning device for highly corrosive materials, which consists of a high-boiling-point storage tank 1, a high-pressure pump 2, a filter 4, pipelines with a heating system 7, and a flushing liquid collection tank 6. The high-boiling-point substances separated by distillation in the high-boiling-point storage tank 1 are pressurized into high-pressure flushing liquid by the high-pressure pump 2. After flushing the solid impurities intercepted by the filter 4 through the pipeline, the mixture is discharged into the flushing liquid collection tank 6. Online cleaning can be performed without disassembling the filter, which effectively solves the problems of high raw material flushing consumption and poor low-temperature cleaning effect in the prior art, reduces raw material loss and ensures cleaning effect.

[0026] The solid impurity online cleaning device for highly corrosive materials in this embodiment comprises the following core components: a high-boiling-point storage tank 1, a high-pressure pump 2, a filter 4, pipelines, a heating system 7, a flushing fluid collection tank 6, a control system, and two sets of control valves (first valve 3 and second valve 5). The connection relationships and functional parameters of each component are as follows:

[0027] High-boiling-point storage tank 1: Used to store high-boiling-point substances obtained after the reaction products of highly hazardous and corrosive materials are separated by subsequent distillation units. These high-boiling-point substances are byproducts with high boiling points separated by the distillation section during the fluorine-chlorine exchange reaction of 1,1,1,3,3-pentachloropropane (240fa) and anhydrous hydrogen fluoride (HF) to prepare HFC-245fa. They have good solubility for solid impurities generated in the reaction (fluorine-chlorine exchange reaction byproducts, mainly high molecular weight fluoropolymers), and can replace traditional raw materials (such as 240fa) as rinsing liquid, reducing raw material loss and realizing waste reuse.

[0028] High-pressure pump 2: A corrosion-resistant plunger-type high-pressure pump 2 is selected, with a rated working pressure range of 0.8-2.5MPa. The boost pressure can be adjusted in real time through the control system with an adjustment accuracy of 0.1MPa. It can output high-pressure flushing fluid pressure that meets the flushing requirements according to the particle size (usually 5-50μm) and adhesion strength of solid impurities in filter 4. When the impurity particle size is large and the adhesion is tight, the pressure can be adjusted to 2.0-2.5MPa; when the impurity particle size is small and the adhesion is loose, the pressure can be adjusted to 0.8-1.5MPa to avoid damage to the filter element due to excessive pressure.

[0029] Filter 4: Used to intercept solid impurities in highly corrosive materials containing solid impurities during the production of HFC-245fa; Filter 4 is equipped with a flushing liquid inlet and an impurity outlet. The flushing liquid inlet is connected to the outlet of the high-pressure pump 2 through a pipeline, and the impurity outlet is connected to the flushing liquid collection tank 6 through a pipeline. Filter 4 can be cleaned online without disassembly, avoiding the cumbersome operation and safety risks of traditional offline disassembly and cleaning.

[0030] Piping: A heat tracing system 7 is wrapped around the outer wall of the pipeline between the high-boiling-point storage tank 1 and the filter 4. A first valve 3 and a second valve 5 are installed sequentially on the pipeline. The first valve 3 is a corrosion-resistant pneumatic shut-off valve, which is installed on the pipeline between the outlet of the high-pressure pump 2 and the inlet of the filter 4 to control the flow of high-pressure flushing fluid into the filter 4. The second valve 5 is also a corrosion-resistant pneumatic shut-off valve, which is installed on the pipeline between the outlet of the filter 4 and the flushing fluid collection tank 6 to control the flow of the mixture of solid impurities and high-boiling-point substances after flushing into the flushing fluid collection tank 6.

[0031] Heat Tracing System 7: In this embodiment, an electric heat tracing system is preferred (a steam heat tracing system can also be selected according to actual working conditions), including an electric heat tracing tape (heating element), a temperature sensor, and a temperature controller; the electric heat tracing tape is wrapped around the outer wall of the pipeline with a power of 66W / m; the temperature sensor is attached to the inner wall of the pipeline with a detection accuracy of ±0.5℃, used to detect the temperature of high-boiling substances in the pipeline in real time and transmit the temperature signal to the temperature controller; the temperature controller is electrically connected to the electric heat tracing tape and can adjust the heating power of the electric heat tracing tape according to the detection signal of the temperature sensor, so that the temperature of high-boiling substances in the pipeline is stabilized within a preset temperature range (the preset temperature in this embodiment is 50-60℃) - this temperature range can ensure the stability of the solubility of high-boiling substances for solid impurities, and avoid the problem of incomplete flushing and secondary blockage caused by the decrease in solubility under low temperature environment.

[0032] Rinse liquid collection tank 6: Used to collect the high-boiling-point mixture carrying solid impurities after rinsing. The collected mixture can be further processed by solid-liquid separation. The separated high-boiling-point substances can be partially reused in the high-boiling-point storage tank 1 to realize resource recycling.

[0033] Control system: A PLC control system is adopted, which is electrically connected to the temperature controllers of the high-pressure pump 2 and the heat tracing system 7, the first valve 3, and the second valve 5 respectively. It has two core functions: ① Controlling the start and stop and output pressure of the high-pressure pump 2. The target pressure can be set through the touch screen, and the system automatically adjusts the speed of the high-pressure pump 2 to achieve the preset pressure; ② Adjusting the power of the electric heat tracing tape of the heat tracing system 7. The heating power is automatically increased or decreased according to the difference between the real-time temperature fed back by the temperature sensor and the preset temperature range.

[0034] Furthermore, after pre-treating the material inside the filter to ensure that the concentration of residual hazardous and corrosive materials is within a safe range, online cleaning of solid impurities can be carried out. The online cleaning process for solid impurities in this embodiment is as follows, and the entire process does not require disassembling the filter 4, achieving fully online operation: Preheating of Heat Tracing System 7: The heat tracing system 7 is started by the control system, and the target temperature of the temperature controller is set to 55℃ (within the preset range of 50-60℃). The temperature sensor detects the temperature of high-boiling substances in the pipeline in real time. When the temperature is below 53℃, the temperature controller controls the electric heating tape to heat at the rated power (66W / m). When the temperature reaches 58℃, the temperature controller controls the electric heating tape to reduce the power to 20W / m. Finally, the temperature of high-boiling substances in the pipeline is stabilized at 55±3℃ to ensure the solubility of solid impurities in high-boiling substances.

[0035] High-pressure flushing start-up: After the pretreatment is qualified, the first valve 3 and the second valve 5 are opened through the control system, and the high-pressure pump 2 is started at the same time. According to the pressure difference before and after the filter 4 (the pressure difference detection value in this embodiment is 0.25MPa), the output pressure of the high-pressure pump 2 is set to 1.8MPa. The high-pressure pump 2 pressurizes the high-boiling matter in the high-boiling matter storage tank 1 to 1.8MPa to form high-pressure flushing fluid, which enters the filter 4 through the pipeline and the first valve 3 to flush the solid impurities trapped on the filter element. The high-pressure flushing fluid disperses the solid impurities attached to the filter element by pressure, and dissolves some of the fine impurities by the solubility of the high-boiling matter, thereby improving the cleaning efficiency.

[0036] Flushing process control: During the flushing process, the temperature of the high boiling point and the flushing pressure are monitored by temperature sensor and pressure sensor (installed on the outlet pipeline of high pressure pump 2). If the temperature deviates from 55±3℃, the control system automatically adjusts the heating power. If the pressure is lower than 1.6MPa or higher than 2.0MPa, the control system automatically adjusts the speed of high pressure pump 2 to ensure that the pressure is stable at 1.8±0.2MPa.

[0037] Flushing cycle ends: When the flushing time reaches the target value, the operator first stops the high-pressure pump 2. After the pressure in the pipeline drops below 0.1MPa, the first valve 3 and the second valve 5 are closed in sequence to complete one online cleaning of solid impurities. At this time, the high-boiling mixture carrying solid impurities after flushing has been discharged into the flushing liquid collection tank 6 through the second valve 5.

[0038] Effect verification: After rinsing, the pressure difference before and after filter 4 is detected by the control system. In this embodiment, the pressure difference drops from 0.25MPa before rinsing to 0.08MPa, which is lower than the normal operating threshold of 0.1MPa. This indicates that the solid impurities on the filter element have been thoroughly cleaned and filter 4 can be put back into the material filtration process in the HFC-245fa production process.

[0039] Furthermore, the online solid impurity cleaning device for highly corrosive materials in this embodiment achieves the following technical effects through the above-described structure and operation process: Reduced raw material consumption: The high-boiling-point substance separated by distillation during the HFC-245fa production process is used as the rinsing liquid to replace the 240fa raw material used in the traditional technology, reducing raw material consumption by 15,000 kg per year, significantly reducing production costs, and realizing the resource utilization of waste. Stable cleaning effect: The temperature of high-boiling-point substances is stabilized within a preset range by the heating system. Even in winter conditions where the ambient temperature is as low as -10℃, the solubility of high-boiling-point substances for solid impurities remains stable. After rinsing, the pressure difference before and after the filter can be reduced to below 0.1MPa, with no secondary clogging. This solves the problem of poor low-temperature rinsing effect in traditional technology. Improved safety and efficiency: Online cleaning can be achieved without disassembling the filter, reducing the cleaning time (including pretreatment) per batch from 4 hours for traditional offline cleaning to 1.5 hours, improving efficiency by 62.5%; at the same time, it avoids the risk of corrosive material leakage during disassembly, ensuring the safety of operators; Automated control: The PLC control system enables automatic control of heating temperature, rinsing pressure, and rinsing time, eliminating the need for manual intervention, reducing operational errors, ensuring consistent cleaning results for each batch, and meeting the continuous and stable operation requirements of the HFC-245fa production unit.

[0040] In summary, the device in this embodiment fully covers the core requirement of online cleaning of solid impurities in highly corrosive materials, solves the key defects of existing technologies, and has the advantages of being economical, efficient, safe and reliable. It can be widely used in the production scenarios of highly corrosive materials with fluorine-chlorine exchange reaction as the core process.

[0041] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. An online solid impurity cleaning device for highly corrosive materials, characterized in that, include: High-boiling-point storage tanks, high-pressure pumps, filters, pipelines, heating systems, and flushing fluid collection tanks; The outlet of the high-boiling-point material storage tank is connected to the inlet of a high-pressure pump via a pipeline. The outlet of the high-pressure pump is connected to the inlet of a filter via a pipeline. The outlet of the filter is connected to a flushing liquid collection tank via a pipeline. A heat tracing system is installed on the pipeline between the high-boiling-point material storage tank and the filter, and a valve for controlling the pipeline's on / off state is also installed on the pipeline. The filter is used to trap solid impurities in highly corrosive materials. The high-pressure pump is used to pressurize the high-boiling-point material in the high-boiling-point material storage tank to form a high-pressure flushing liquid, which is used to flush away the solid impurities trapped by the filter. The flushed solid impurities are discharged into the flushing liquid collection tank together with the high-boiling-point material.

2. The online solid impurity cleaning device for highly corrosive materials according to claim 1, characterized in that, The heat tracing system is either an electric heat tracing system or a steam heat tracing system.

3. The online solid impurity cleaning device for highly corrosive materials according to claim 1, characterized in that, The high-boiling-point substances stored in the high-boiling-point substance storage tank are derived from the high-boiling-point substances obtained after separation by a subsequent distillation unit from the reaction products of highly corrosive materials.

4. The online solid impurity cleaning device for highly corrosive materials according to claim 1, characterized in that, The boosting pressure of the high-pressure pump is adjustable, and the pressure of the boosted high-pressure flushing fluid can meet the flushing requirements of solid impurities trapped in the filter.

5. The online solid impurity cleaning device for highly corrosive materials according to claim 1, characterized in that, The valve includes a first valve and a second valve; the first valve is installed on the pipeline between the high-pressure pump outlet and the filter inlet, and is used to control the flow of high-pressure flushing fluid into the filter; the second valve is installed on the pipeline between the filter outlet and the flushing fluid collection tank, and is used to control the flow of the mixture of solid impurities and high-boiling substances after flushing into the flushing fluid collection tank.

6. The online solid impurity cleaning device for highly corrosive materials according to claim 1, characterized in that, The highly corrosive material is a material containing solid impurities generated during the production of 1,1,1,3,3-pentafluoropropane; the solid impurities are byproducts generated during the fluorine-chlorine exchange reaction between 1,1,1,3,3-pentachloropropane and anhydrous hydrogen fluoride.

7. The online solid impurity cleaning device for highly corrosive materials according to claim 1, characterized in that, The device can clean solid impurities online without disassembling the filter. By flushing the filter with high-pressure flushing fluid, solid impurities are directly discharged into the flushing fluid collection tank along with high-boiling-point substances, avoiding the need for offline cleaning of the filter.

8. The online solid impurity cleaning device for highly corrosive materials according to claim 1, characterized in that, Before high-pressure rinsing, the filter needs to undergo a pretreatment process to replace any remaining highly corrosive materials inside. After the pretreatment is completed, a high-pressure rinsing solution is then delivered by a high-pressure pump to remove solid impurities.

9. The online solid impurity cleaning device for highly corrosive materials according to claim 1, characterized in that, The device also includes a control system, which is electrically connected to the high-pressure pump and the heat tracing system respectively; the control system is used to control the start and stop of the high-pressure pump and its output pressure, and at the same time to adjust the heating power of the heat tracing system.

10. The online solid impurity cleaning device for highly corrosive materials according to claim 9, characterized in that, The heat tracing system includes a temperature sensor and a temperature controller. The temperature sensor is attached to the pipeline and is used to detect the temperature of the high-boiling-point substance in the pipeline in real time and transmit the temperature signal to the temperature controller. The temperature controller is electrically connected to the heating element of the heat tracing system and is used to adjust the power of the heating element according to the detection signal of the temperature sensor to stabilize the temperature of the high-boiling-point substance in the pipeline within a preset temperature range.

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