A complete set of equipment for continuous production of lignite wax

Abstract

The utility model relates to a kind of lignite extraction lignite wax's continuous production complete equipment, including extractor, desolventizing machine, condenser, first heat exchanger and evaporator unit;First heat exchanger includes first heat exchange buffer tank and first heat exchange coil;The extraction liquid output end of extractor is connected with the input end of evaporator group after first heat exchange buffer tank;The lignite output end of extractor is connected with the input end of desolventizing machine, and the gas output end of desolventizing machine and evaporator unit is connected with condenser after first heat exchange coil, first heat exchange coil is arranged around first heat exchange buffer tank, so that liquid extraction liquid exchanges heat with gaseous extraction liquid output from desolventizing machine and evaporator unit before entering evaporator group, to raise the temperature of liquid extraction liquid before entering evaporator group, save heating energy consumption;Gas extraction liquid is released heat in advance before entering condenser simultaneously, reduce the temperature before entering condenser, to save cooling energy consumption.

Description

Technical Field

[0001] This utility model relates to the field of lignite wax extraction technology, specifically to a complete set of equipment for continuous production of lignite wax extraction from lignite. Background Technology

[0002] Lignite wax is a high-carbon, long-chain hydrocarbon product extracted from low-rank lignite using organic solvents. It is widely used in chemical, energy, and fine materials industries. Refer to CN101434868B for a production method of extracting lignite wax from lignite. The existing extraction process mainly includes the following steps: drying and pretreating the lignite raw material, followed by solid-liquid extraction with an extractant to obtain a liquid extract rich in lignite wax; filtering the extract and then sending it to a multi-stage evaporation unit for concentration and separation, removing most of the solvent through heating and evaporation; the high-concentration liquid phase after evaporation then enters the crystallization section to precipitate the lignite wax product. Simultaneously, the evaporated solvent vapors and organic vapors escaping from the solvent removal dryer enter a condensation system to condense and recycle the extract.

[0003] In the above process flow, there is a significant thermal energy gradient: on the one hand, the extractant input to the multi-stage evaporator is usually in a relatively medium temperature state (about 70-85°C), which is lower than the set evaporation temperature (about 140-160°C). The multi-stage evaporator needs to consume thermal energy to heat it to the evaporation temperature in order to obtain extractant vapor; on the other hand, the extractant vapor output from the evaporator and desolvator is usually at a high temperature (about 140-160°C), which is much higher than the condensation temperature. It needs to dissipate heat quickly to rapidly cool the gaseous extractant to below 40-50°C for liquefaction, which requires a large amount of electricity and cooling water for heat dissipation.

[0004] Therefore, it is necessary to study a complete set of equipment for continuous production of lignite wax from lignite. Utility Model Content

[0005] Therefore, the purpose of this utility model is to provide a complete set of continuous production equipment for extracting lignite wax from lignite, which can effectively solve the problem of high energy consumption in the evaporation and condensation process in the existing lignite wax extraction process.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0007] A continuous production line for extracting lignite wax from lignite includes an extractor, a solvent remover, a condenser, a first heat exchanger, and an evaporator.

[0008] The first heat exchanger includes a first heat exchange buffer tank and a first heat exchange coil;

[0009] The extractor's output end is connected to the evaporator group's input end via a first heat exchange buffer tank.

[0010] The lignite output end of the extractor is connected to the input end of the desolventizer.

[0011] The solid output end of the desolventizing machine is connected to the lignite cooling chamber.

[0012] The gas output ends of both the solvent extractor and the evaporator are connected to the condenser via the first heat exchange coil. The first heat exchange coil is arranged around the first heat exchange buffer tank, so that the liquid extractant exchanges heat with the gaseous extractant output from the solvent extractor and the evaporator before entering the evaporator group.

[0013] The output of the condenser is connected to the solvent transfer tank, and the output of the solvent transfer tank is connected to the extractor.

[0014] Furthermore, it also includes a second heat exchanger, which includes a second heat exchange buffer tank and a second heat exchange coil;

[0015] The extractor's output end is connected to the input end of the first heat exchange buffer tank via a second heat exchange buffer tank.

[0016] The output end of the solvent transfer tank is connected to the extractor via a second heat exchange coil.

[0017] The second heat exchange coil is arranged around the second heat exchange buffer tank, so that the liquid extractant exchanges heat with the liquid extractant output from the solvent transfer tank before entering the first heat exchange buffer tank.

[0018] Furthermore, it also includes a third heat exchanger, which includes a third heat exchange coil;

[0019] The output end of the second heat exchange coil is connected to the extractor via the third heat exchange coil;

[0020] The third heat exchange coil is arranged around the lignite cooling chamber, so that the liquid extract liquid exchanges heat with the lignite cooling chamber before entering the extractor.

[0021] Furthermore, the evaporator unit includes a single-effect rising film evaporator, a double-effect falling film evaporator, a triple-effect falling film evaporator, and a vacuum concentrator connected in sequence.

[0022] Furthermore, both the solvent removal machine and the evaporator are located in the high-temperature evaporation zone.

[0023] The gas output ends of the desolventizer, the first-effect rising film evaporator, the second-effect falling film evaporator, the third-effect falling film evaporator, and the vacuum concentrator are all connected to the steam delivery pipe, which is connected to the condenser via the first heat exchange coil.

[0024] Furthermore, it also includes a separator, which includes a cyclone separator and a sieve separator. The input end of the cyclone separator is connected to the extract output end of the extractor, the top flow output end of the cyclone separator is connected to the sieve separator, and the underflow output end of the sieve separator is connected to the input end of the first heat exchange buffer tank.

[0025] The beneficial effects of the above technical solution are:

[0026] This invention, by incorporating a first heat exchanger, allows the liquid extractant (around 80°C) to exchange heat with the gaseous extractant (around 150°C) output from the desolvation unit and evaporator unit before entering the evaporator assembly. This facilitates the recovery of waste heat from the high-temperature gas within the system, raising the temperature of the liquid extractant before it enters the evaporator assembly, reducing the temperature gradient, and saving heating energy. Simultaneously, the gaseous extractant releases heat before entering the condenser, lowering its temperature before entering the condenser and reducing the temperature gradient, thus saving cooling energy. It effectively utilizes the thermal energy of the high-temperature gas that would otherwise require forced cooling to heat the medium-temperature extractant before it enters the evaporator unit. This not only reduces the temperature difference burden of high-temperature steam directly entering the condenser, reducing the cooling load, but also lowers the external heat source consumption required for preheating the extractant, optimizing the overall thermal energy path, improving system energy efficiency, and reducing energy waste. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the system in Example 1;

[0028] Figure 2 This is a schematic diagram of the system in Example 2;

[0029] Figure 3 This is a schematic diagram of the system in Example 3;

[0030] Figure 4 This is an enlarged view of the heat exchanger section of Example 3.

[0031] Figure labels: 1 is extractor, 2 is solvent remover, 3 is condenser, 4 is first heat exchanger, 5 is evaporator, 6 is lignite cooling chamber, 7 is second heat exchanger, 8 is third heat exchanger, 9 is steam conveying pipe, 10 is hydrocyclone separator, 11 is sieve separator, 12 is solvent transfer tank, 13 is high-temperature evaporation zone, 401 is first heat exchange buffer tank, 402 is first heat exchange coil, 501 is single-effect rising film evaporator, 502 is double-effect falling film evaporator, 503 is triple-effect falling film evaporator, 504 is vacuum concentrator, 701 is second heat exchange buffer tank, 702 is second heat exchange coil, 801 is third heat exchange coil. Detailed Implementation

[0032] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0033] Example 1: This example aims to provide a complete set of equipment for continuous production of lignite wax extraction from lignite. It is mainly used in the production process of lignite wax extraction from lignite, addressing the problem of high energy consumption in the evaporation and condensation stages of existing lignite wax extraction processes.

[0034] A continuous production line for extracting lignite wax from lignite, such as... Figure 1 It includes an extractor 1, a solvent remover 2, a condenser 3, a first heat exchanger 4, and an evaporator 5. The first heat exchanger 4 includes a first heat exchange buffer tank 401 and a first heat exchange coil 402.

[0035] Extractor 1 uses existing equipment to input lignite and extractant, and outputs moistened lignite and an extract rich in lignite wax. The extractant uses existing organic extractants (benzene, toluene, acetone, or an ethanol-benzene mixture, etc.), and the weight ratio of the extractant to lignite is generally (1-1.4):1. In extractor 1, the lignite undergoes permeation, soaking, rinsing, and draining processes to extract lignite wax. The temperature inside extractor 1 is maintained at 80–90°C.

[0036] The extractor 1 has an extractant output end for discharging extractant rich in lignite wax at a temperature of 80–90°C. It also includes a separator, comprising a hydrocyclone separator 10 and a sieve separator 11. The input end of the hydrocyclone separator 10 is connected to the extractant output end of the extractor 1, allowing the lignite wax-rich extractant to enter the hydrocyclone separator 10 for solid-liquid separation. This separates the larger coal particles carried in the extractant, which are then discharged from the underflow of the hydrocyclone separator 10.

[0037] The top outlet of the hydrocyclone separator 10 is connected to the sieve separator 11, allowing the extract to be filtered through the sieve structure to remove finer coal dust, forming a two-stage filtration process. After two-stage filtration, the coal dust content in the extract is less than 0.1%.

[0038] The undersize output of the sieve separator 11 is connected to the input of the first heat exchange buffer tank 401, allowing the extracted liquid after sieving to enter the first heat exchange buffer tank 401. The output of the first heat exchange buffer tank 401 is connected to the input of the evaporator assembly, allowing the lignite wax-rich extract to enter the evaporator unit 5 for evaporation and separation of the lignite wax. The evaporator unit 5 heats the extract to 155–165°C to evaporate the extract, yielding a gaseous extract (around 150°C) and the lignite wax product.

[0039] Evaporation unit 5 includes a single-effect rising film evaporator 501, a double-effect falling film evaporator 503, a triple-effect falling film evaporator 503, and a vacuum concentration tank 504 connected in sequence. The extract rich in lignite wax is filtered by the separators and then subjected to triple-effect evaporation separation. After 50% of the extractant is removed by the single-effect rising film evaporator 501, it is pumped to the double-effect falling film evaporator 503 to remove 80% of the extractant, and then pumped to the triple-effect falling film evaporator 503 to remove 95% of the extractant. The resulting lignite wax, containing 5% organic solvent, is then transported to the vacuum concentration tank 504 for vacuum concentration. Under a vacuum of 300 Pa, the lignite wax is heated to 100-140℃ and concentrated until the lignite wax concentration is above 95% (density of 1.02 g / cm³), thus obtaining the lignite wax product, which is then transported to the granulation and packaging section.

[0040] The lignite output end of extractor 1 is connected to the input end of desolventizer 2. Desolventizer 2 is heated by steam to 140-160°C to evaporate and recover the extractant carried in the extracted lignite, and can output dewaxed lignite at about 150°C and high-temperature gaseous extract at about 150°C. The solid output end of desolventizer 2 is connected to lignite cooling chamber 6, and the dewaxed lignite is output to lignite cooling chamber 6 for cooling.

[0041] The solvent extractor 2 and the evaporator 5 are both located in the high-temperature evaporation zone 13 for centralized deployment of high-temperature evaporation equipment. The gas output ends of the solvent extractor 2, the first-effect rising film evaporator 501, the second-effect falling film evaporator 503, the third-effect falling film evaporator 503 and the vacuum concentrator 504 are all connected to the steam conveying pipe 9 for centralized output of high-temperature gaseous extract.

[0042] The steam delivery pipe 9 is connected to the condenser 3 via the first heat exchange coil 402. The first heat exchange coil 402 is arranged around the first heat exchange buffer tank 401, so that the liquid extract (around 80°C) exchanges heat with the gaseous extract (around 150°C) output from the desolventizer 2 and the evaporator 5 before entering the evaporator group. This raises the temperature of the liquid extract before entering the evaporator group, reduces the temperature gradient, and saves heating energy. At the same time, it lowers the temperature of the gaseous extract before entering the condenser 3, reduces the temperature gradient, and saves cooling energy.

[0043] The gaseous extractant distilled from the solvent separator 2 and evaporator 5 enters the condenser 3, where it is condensed to approximately 40°C to obtain a liquefied extractant, which is then stored in the solvent transfer tank 12. Water in the extractant can be removed using a water separator or similar equipment. Fresh extractant is replenished from the solvent transfer tank 12 when necessary. The solvent transfer tank 12 ultimately outputs the extractant to the extractor 1, thus achieving extraction recycling.

[0044] Example 2 is basically the same as Example 1, except that a second heat exchanger 7 is provided, so that the liquid extract can exchange heat with the liquid extract output from the solvent transfer tank 12 before entering the first heat exchange buffer tank 401, so as to reduce the temperature of the extract entering the first buffer tank and increase the temperature of the liquid extract output from the solvent transfer tank 12.

[0045] like Figure 2 The second heat exchanger 7 includes a second heat exchange buffer tank 701 and a second heat exchange coil 702. The extract liquid output end of the extractor 1 is connected to the input end of the first heat exchange buffer tank 401 through the second heat exchange buffer tank 701, and the output end of the solvent transfer tank 12 is connected to the extractor 1 through the second heat exchange coil 702. The second heat exchange coil 702 is arranged around the second heat exchange buffer tank 701, so that the liquid extract liquid (around 80°C) exchanges heat with the liquid extract liquid (around 40°C) output from the solvent transfer tank 12 before entering the first heat exchange buffer tank 401, so that the liquid extract liquid is cooled before entering the first heat exchange buffer tank 401, thereby increasing the temperature difference in the first heat exchanger 4, further enhancing the pre-cooling effect of the first heat exchanger 4 on the gaseous extract liquid during operation, and reducing the energy consumption of the condenser 3. Meanwhile, the liquid extract output from the solvent transfer tank 12 is preheated to reduce the temperature difference with the working temperature of the extractor 1 (around 80°C), thereby reducing the heating energy consumption of the extractor 1.

[0046] Example 3 is basically the same as Example 2, except that a third heat exchanger 8 is provided, so that the liquid extractant exchanges heat with the lignite cooling chamber 6 before entering the extractor 1, and uses the residual heat from the lignite cooling chamber 6 to preheat the extractant before entering the extractor 1.

[0047] like Figure 3 and Figure 4 The third heat exchanger 8 includes a third heat exchange coil 801; the output end of the second heat exchange coil 702 is connected to the extractor 1 through the third heat exchange coil 801; the third heat exchange coil 801 is arranged around the lignite cooling chamber 6, so that the liquid extract liquid exchanges heat with the lignite cooling chamber 6 (about 150°C) before entering the extractor 1, so as to preheat or keep the extract liquid before entering the extractor 1, thereby reducing the heating energy consumption of the extractor 1, and at the same time promoting the cooling efficiency of the lignite cooling chamber 6 and reducing cooling energy consumption.

Claims

1. A continuous production line for extracting lignite wax from lignite, characterized in that: Includes an extractor, a solvent remover, a condenser, a first heat exchanger, and an evaporator; The first heat exchanger includes a first heat exchange buffer tank and a first heat exchange coil; The extractor's output end is connected to the evaporator group's input end via a first heat exchange buffer tank. The lignite output end of the extractor is connected to the input end of the desolventizer. The solid output end of the desolventizing machine is connected to the lignite cooling chamber. The gas output ends of both the solvent extractor and the evaporator are connected to the condenser via the first heat exchange coil. The first heat exchange coil is arranged around the first heat exchange buffer tank, so that the liquid extractant exchanges heat with the gaseous extractant output from the solvent extractor and the evaporator before entering the evaporator group. The output of the condenser is connected to the solvent transfer tank, and the output of the solvent transfer tank is connected to the extractor.

2. The continuous production line equipment for extracting lignite wax from lignite according to claim 1, characterized in that: It also includes a second heat exchanger, which includes a second heat exchange buffer tank and a second heat exchange coil; The extractor's output end is connected to the input end of the first heat exchange buffer tank via a second heat exchange buffer tank. The output end of the solvent transfer tank is connected to the extractor via a second heat exchange coil. The second heat exchange coil is arranged around the second heat exchange buffer tank, so that the liquid extractant exchanges heat with the liquid extractant output from the solvent transfer tank before entering the first heat exchange buffer tank.

3. The continuous production line equipment for extracting lignite wax from lignite according to claim 2, characterized in that: It also includes a third heat exchanger, which includes a third heat exchange coil; The output end of the second heat exchange coil is connected to the extractor via the third heat exchange coil; The third heat exchange coil is arranged around the lignite cooling chamber, so that the liquid extract liquid exchanges heat with the lignite cooling chamber before entering the extractor.

4. A continuous production line for extracting lignite wax from lignite according to any one of claims 1-3, characterized in that: The evaporator unit includes a single-effect rising film evaporator, a double-effect falling film evaporator, a triple-effect falling film evaporator, and a vacuum concentration tank connected in sequence.

5. A continuous production line for extracting lignite wax from lignite according to claim 4, characterized in that: Both the solvent removal machine and the evaporator are located in the high-temperature evaporation zone. The gas output ends of the desolventizer, the first-effect rising film evaporator, the second-effect falling film evaporator, the third-effect falling film evaporator, and the vacuum concentrator are all connected to the steam delivery pipe, which is connected to the condenser via the first heat exchange coil.

6. A continuous production line for extracting lignite wax from lignite according to any one of claims 1-3, characterized in that: It also includes a separator, which includes a cyclone separator and a sieve separator. The input end of the cyclone separator is connected to the extract output end of the extractor, the top flow output end of the cyclone separator is connected to the sieve separator, and the underflow output end of the sieve separator is connected to the input end of the first heat exchange buffer tank.

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