A continuous degreasing device for microcrystalline wax

Abstract

This utility model discloses a continuous deoiling device for microcrystalline wax, including a sealed wax melting tank and a deoiling device. The sealed wax melting tank transports the mixture to the inside of a spiral plate heat exchanger via a variable frequency pump. The spiral plate heat exchanger is connected to a high and low temperature integrated machine, which can circulate and cool the coolant flowing inside the spiral plate heat exchanger. The spiral plate heat exchanger transports the crystallized mixture to the inside of a centrifuge. The centrifuge separates the crystallized wax from the filtrate through centrifugal action, and the separated filtrate enters the sealed filtrate tank for recycling. This utility model can achieve continuous deoiling of microcrystalline wax through the synergistic effect of components such as the sealed wax melting tank, variable frequency pump, spiral plate heat exchanger, and centrifuge. At the same time, the curved structure in the channel of the spiral plate heat exchanger forces the fluid to form a strong spiral flow. The high flow velocity and turbulence can scour the wall surface and prevent wax crystals or impurities from depositing.

Description

Technical Field

[0001] This utility model mainly relates to the field of microcrystalline wax technology, specifically a continuous degreasing device for microcrystalline wax. Background Technology

[0002] Microcrystalline wax, an important product in the petrochemical industry, is widely used in packaging materials, cosmetic bases, and lubricant additives due to its excellent ductility and adhesion. However, natural microcrystalline wax raw materials typically contain 8%-15% oil, and the presence of this oil significantly affects key performance indicators such as melting point and hardness. Therefore, the deoiling process has become a core step in the production of microcrystalline wax.

[0003] Traditional microcrystalline wax degreasing processes generally employ an intermittent operation mode. Intermittent operation involves a cyclical process of "feeding-heating-crystallization-separation-washing," with a single batch processing time of 8-12 hours, resulting in low production efficiency and difficulty in meeting the demands of large-scale production. Intermittent operation requires reheating the molten wax for each batch change, leading to 20-30% higher steam consumption compared to continuous processes, resulting in significant energy consumption. Furthermore, the manual adjustment of process parameters (such as crystallization temperature and stirring rate) between batches in intermittent operation can easily cause poor product consistency. Therefore, a continuous microcrystalline wax degreasing device is proposed. Utility Model Content

[0004] This utility model provides a solution that is significantly different from existing technologies, addressing the problem that existing technologies are too simplistic. It mainly provides a microcrystalline wax continuous deoiling device to solve the technical problems mentioned in the background, such as the low production efficiency, high energy consumption, and poor product consistency of traditional deoiling processes that mostly adopt intermittent operation.

[0005] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows:

[0006] A continuous deoiling device for microcrystalline wax includes a sealed wax melting tank and a deoiling device. The sealed wax melting tank uses a variable frequency pump to transport the mixture to the inside of a spiral plate heat exchanger. The spiral plate heat exchanger is connected to a high and low temperature integrated machine, which can circulate and cool the coolant flowing inside the spiral plate heat exchanger. The spiral plate heat exchanger transports the crystallized mixture to the inside of a centrifuge. The centrifuge separates the crystallized wax from the filtrate through centrifugal action, and the separated filtrate enters the sealed filtrate tank for recycling.

[0007] Preferably, the sealed wax melting tank is used to melt microcrystalline wax raw materials and add solvent according to the mass ratio to form a mixture. The sealed wax melting tank is equipped with a variable frequency stirring structure with adjustable speed and a heating component is installed inside the sealed wax melting tank.

[0008] Preferably, a polar additive is added to the solvent to improve the purity and color of the product and remove the gum.

[0009] Preferably, the oil removal device is made of corrosion-resistant and explosion-proof materials, and adopts a closed-loop structure. The oil removal device is used in conjunction with an online monitoring system.

[0010] Preferably, the spiral plate heat exchanger has two sets of spiral channels inside, and the coolant undergoes countercurrent heat exchange in one set of spiral channels.

[0011] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0012] This invention enables continuous deoiling of microcrystalline wax through the synergistic action of components such as a sealed wax melting tank, a variable frequency pump, a spiral plate heat exchanger, and a centrifuge. At the same time, the curved structure within the spiral plate heat exchanger channel forces the fluid to form a strong spiral flow. The high flow velocity and turbulence can scour the wall surface, preventing the deposition of wax crystals or impurities. In addition, the device uses corrosion-resistant and explosion-proof materials and a closed-loop design, coupled with an online monitoring system, which reduces solvent evaporation and environmental pollution, as well as safety risks.

[0013] The present invention will be explained in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0015] Numbering on the map:

[0016] 1. Sealed wax melting tank; 2. Variable frequency pump; 3. Spiral plate heat exchanger; 4. High and low temperature integrated unit; 5. Sealed filtrate tank; 6. Oil removal device; 7. Centrifuge. Detailed Implementation

[0017] To facilitate understanding of this utility model, a more comprehensive description of the utility model will be given below with reference to the accompanying drawings, which show several embodiments of the utility model. However, the utility model can be implemented in different forms and is not limited to the embodiments described in the text. On the contrary, these embodiments are provided to make the disclosure of the utility model more thorough and comprehensive.

[0018] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly associated with those skilled in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0020] Please refer to the appendix carefully. Figure 1 A continuous deoiling device for microcrystalline wax is disclosed. The deoiling device 6 includes a sealed wax melting tank 1, which is used to melt microcrystalline wax raw materials and add solvent according to the mass ratio to form a mixture. The sealed wax melting tank 1 is equipped with a variable frequency stirring structure with adjustable speed. The variable frequency stirring structure mainly consists of a variable frequency motor, a transmission component and stirring blades. The variable frequency motor serves as the power source, and its speed can be flexibly adjusted within the range of 50 to 500 rpm according to the requirements of the microcrystalline wax deoiling process, thereby precisely controlling the stirring speed to meet the production requirements of different stages. The sealed wax melting tank 1 is also equipped with a heating component, which includes a heating furnace, a circulating oil pump and pipelines. The heating furnace adopts electric heating or gas heating to heat the heat transfer oil to a set temperature, usually 120-180℃. The circulating oil pump delivers the high-temperature heat transfer oil to the jacket or coil of the sealed wax melting tank 1 through pipelines, and heats and melts the microcrystalline wax raw materials in the tank through heat conduction.

[0021] Adding polar additives (such as methanol) to the solvent to improve product purity and color removes gums. The solvent must have high selectivity in dissolving oils but not waxes, such as methyl ethyl ketone (MEK)-toluene mixed solvent, low toxicity, and easy recovery. The high selectivity of the solvent allows the subsequent equipment to flexibly adjust process parameters, such as crystallization temperature and solvent type, thereby producing special waxes with different melting points to meet the diversified needs of the market. The addition of polar additives reduces the residue of gums and asphaltenes, and improves the purity and color of the product.

[0022] The sealed wax melting tank 1, via a variable frequency pump 2, delivers the heated mixture to a specified temperature into the spiral plate heat exchanger 3. All power equipment operates collaboratively through a PLC control system, automatically adjusting power output according to production load to ensure stable and efficient system operation. The spiral plate heat exchanger 3 is equipped with a heating system for the feed. If the temperature of the mixture before reaching the spiral plate heat exchanger 3 is below the wax crystal precipitation point (usually 35-40℃), premature crystallization will occur, leading to pipe blockage. The heating system maintains the feed temperature at 50-60℃, ensuring the mixture flows stably in a liquid state. The heating system employs a circulating heat transfer oil heating method. The electric heat tracing composite design is arranged around the feed pipe and main body of the spiral plate heat exchanger 3. The heat tracing system is existing technology and will not be described in detail. The spiral plate heat exchanger 3 is a high-efficiency heat exchange device with a unique structural design. It is mainly composed of two parallel metal plates rolled into two spiral channels. The curved structure of the spiral plate channels forces the fluid to form a strong spiral flow. The high flow velocity and turbulence can scour the wall surface and prevent wax crystals or impurities from depositing. Compared with shell and tube heat exchangers, the scaling rate can be reduced by 30% to 50%. By adjusting the shape of the baffles and optimizing the fluid distribution, coking or scaling caused by local low flow rates can be avoided. The spiral plate heat exchanger 3 has a detachable structure, which facilitates later maintenance. The spiral plate heat exchanger 3 is existing technology and will not be described in detail. The spiral plate heat exchanger 3 is connected to the high and low temperature integrated unit 4, and the high and low temperature integrated unit 4 can circulate and cool the coolant flowing inside the spiral plate heat exchanger 3. The coolant undergoes countercurrent heat exchange in a set of spiral flow channels. The high and low temperature integrated unit 4 serves as the temperature control center for the coolant and has a built-in refrigeration system such as a compressor, condenser, and heating system electric heating elements. It can precisely control the temperature of the coolant (usually ethylene glycol aqueous solution or silicone oil) to the range of -10℃ to 30℃ according to process requirements. After the coolant completes temperature regulation in the integrated unit, it is transported to the spiral plate heat exchanger 3 through a circulation pump.

[0023] The spiral plate heat exchanger 3 transports the crystallized mixture to the centrifuge 7. The centrifuge 7 separates the crystallized wax from the filtrate through centrifugation. The centrifuge 7 is equipped with a high-speed rotating drum, which is usually made of 316L stainless steel and has a polished inner wall. When the crystallized mixture (containing microcrystalline wax crystals and solvent filtrate) enters the drum, the drum rotates at a high speed of 2000~4000 rpm, generating a centrifugal acceleration that can reach 500~2000 times the acceleration due to gravity. Under this strong centrifugal force field, the denser microcrystalline wax crystals (approximately 0.9–1.1 g / cm³) settle towards the inner wall of the drum, while the less dense solvent filtrate (approximately 0.8–0.9 g / cm³) is thrown towards the outer side of the crystals, forming a solid-liquid separation interface. The separated filtrate enters the sealed filtrate tank 5 for recycling. The filtrate is then pumped to a distillation column (usually a packed column or plate column) by a centrifugal pump. Through distillation and other recovery steps, the solvent is purified and separated. After purification, the solvent is returned to the sealed wax melting tank 1 by a transfer pump for recycling.

[0024] The oil removal device 6 is made of corrosion-resistant and explosion-proof materials. It is used in conjunction with an online monitoring system, which includes a temperature monitoring module, a pressure and flow monitoring module, and a composition and concentration monitoring module. The above structure is existing technology and will not be described in detail. The above structure can prevent the leakage of flammable gases and handle them in a timely manner. The oil removal device 6 adopts a closed-loop structure, which can reduce solvent emissions and reduce environmental pollution.

[0025] The specific operating procedure of this utility is as follows: Microcrystalline wax raw material, solvent and polar additives in the mass ratio are added to the sealed wax melting tank 1, the prepared materials are heated by the heating component, and the materials are fully mixed by the frequency conversion stirring structure.

[0026] After heating and mixing, the mixture is transported to the spiral plate heat exchanger 3 by the variable frequency pump 2. The temperature is controlled by the high and low temperature integrated machine 4 to crystallize the mixture and then enter the centrifuge 7. The wax filter cake and filtrate are separated at the speed of the centrifuge 7. The filtrate flows into the filtrate sealed tank 5 for static filtration and then sent to the distillation tower for purification. The recovered solvent is returned to the sealed wax melting tank 1 for recycling.

[0027] The present invention has been described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvement made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, shall be within the protection scope of the present invention.

Claims

1. A continuous degreasing device for microcrystalline wax, characterized in that: The system includes a sealed wax melting tank (1) and an oil removal device (6). The sealed wax melting tank (1) transports the mixture to the spiral plate heat exchanger (3) via a variable frequency pump (2). The spiral plate heat exchanger (3) is connected to a high and low temperature integrated machine (4), and the high and low temperature integrated machine (4) can circulate and cool the coolant flowing inside the spiral plate heat exchanger (3). The spiral plate heat exchanger (3) transports the crystallized mixture to the centrifuge (7). The centrifuge (7) separates the crystallized wax from the filtrate through centrifugal action, and the separated filtrate enters the filtrate sealed tank (5) for recycling.

2. The microcrystalline wax continuous degreasing device according to claim 1, characterized in that: The sealed wax melting tank (1) is used to melt microcrystalline wax raw materials and add solvent according to the mass ratio to form a mixture. The sealed wax melting tank (1) is equipped with a variable frequency stirring structure with adjustable speed and a heating component is installed inside the sealed wax melting tank (1).

3. The microcrystalline wax continuous degreasing device according to claim 2, characterized in that: The solvent is added with polar additives to improve product purity and color and remove gum.

4. The microcrystalline wax continuous degreasing device according to claim 1, characterized in that: The oil removal device (6) is made of corrosion-resistant and explosion-proof materials, and the oil removal device (6) adopts a closed-loop structure. The oil removal device (6) is used in conjunction with an online monitoring system.

5. The microcrystalline wax continuous degreasing device according to claim 1, characterized in that: The spiral plate heat exchanger (3) has two sets of spiral channels inside, and the coolant undergoes countercurrent heat exchange in one set of spiral channels.

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