Horizontal Evaporation and Concentration System for Organic Solvents

Abstract

This utility model discloses a horizontal evaporation and concentration system for organic solvents. The outlet of the organic solution feed pipe is connected to the cold-side inlet of the concentrate preheater and the solvent preheater via a feed pump. The cold-side outlets of both preheaters are connected to the spray feed inlet of the first horizontal evaporator, and the outlet of the first evaporation concentrate is connected to the hot side of the concentrate preheater. The outlet of the separation section of the second horizontal evaporator is connected to the tube-side inlet of the first horizontal evaporator via a steam compressor. The condensate outlet of the first evaporation tube-side is connected to a condensate tank and, via a condensate pump, to the water collection tank of the second horizontal evaporator, and further connected to the spray feed inlet of the second horizontal evaporator via a spray pump. The outlet of the first evaporation separation section is connected to the inlet of the second evaporation tube-side via a solvent vapor pipe. The solvent outlet of the second evaporation tube-side is connected to a solvent condensate tank, and the outlet of the solvent condensate tank is connected to the hot side of the solvent preheater via a solvent discharge pump. This system has a low height, small footprint, low investment cost and risk, high production efficiency, and low energy consumption.

Description

Technical Field

[0001] This utility model relates to an evaporation and concentration system, and more particularly to a horizontal evaporation and concentration system for organic solvents, in the field of resource recycling technology. Background Technology

[0002] Organic solvents are widely used in daily life and industrial production. They have small molecular weights, are liquid at room temperature, and include many types of substances, such as alkanes, alkenes, alcohols, aldehydes, amines, esters, ethers, ketones, aromatic hydrocarbons, hydrogenated hydrocarbons, terpenes, halogenated hydrocarbons, heterocyclic compounds, nitrogen-containing compounds, and sulfur-containing compounds. Most of them are toxic to humans, commonly causing neurotoxicity, hematologic toxicity, hepatotoxicity, nephrotoxicity, and skin and mucous membrane irritation. The volatility of organic solvents necessitates careful safety precautions during dissolution and cleaning processes to avoid direct skin contact or inhalation of vapors.

[0003] Organic solvents can dissolve some organic compounds that are insoluble in water (such as oils, waxes, resins, rubbers, dyes, etc.). They are characterized by being liquid at room temperature and pressure, having high volatility, and having no change in the properties of the solute and solvent during the dissolution process.

[0004] Organic solvent recovery, dehydration, and concentration of dissolved compounds are all crucial steps in industrial production. Currently, distillation purification is commonly used for organic solvent recovery; the latest technology for organic solvent dehydration is MVR heat pump technology, which can reduce steam consumption and significantly lower operating costs; however, for the concentration of dissolved compounds in solvents, traditional single-effect evaporation distillation remains the standard process due to the incompatibility of steam compressors with low compression efficiency, high system risk, low solvent heat exchange efficiency, and high system explosion-proof requirements. This results in high steam energy consumption, tall equipment, difficult maintenance, and high construction costs.

[0005] To address the problem of concentrating compounds dissolved in organic solvents, there is an urgent need for a novel horizontal solvent evaporation and concentration system that is energy-saving, highly efficient, low-profile, easy to maintain, low-investment, small-footprint, and low-risk. Utility Model Content

[0006] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, and such simplifications or omissions should not be construed as limiting the scope of the present invention.

[0007] In view of the problems existing in the above and / or prior art, this utility model is proposed.

[0008] The purpose of this invention is to overcome the problems existing in the prior art and provide a horizontal evaporation and concentration system for organic solvents, which has low equipment height, small footprint, easy maintenance, low investment cost and risk, high production efficiency and low energy consumption.

[0009] To solve the above technical problems, this utility model provides a horizontal evaporation and concentration system for organic solvents, including an organic solution feed pipe G1. The outlet of the organic solution feed pipe G1 is connected to the inlet of the feed pump B1. The outlet of the feed pump B1 is connected to the cold side inlets of the concentrate preheater 3 and the solvent preheater 4, respectively. The cold side outlets of the concentrate preheater 3 and the solvent preheater 4 are both connected to the spray feed inlet of the first horizontal tube falling film evaporator 1. The concentrate outlet of the first horizontal tube falling film evaporator 1 is connected to the hot side inlet of the concentrate preheater 3 through a concentrate discharge pump B2. The hot side outlet of the concentrate preheater 3 is connected to the concentrate discharge pipe G2. The outlet of the separation section of the second horizontal tube falling film evaporator 2 is connected to the inlet of the steam compressor M1. The outlet of the steam compressor M1 is connected to the tube inlet of the first horizontal tube falling film evaporator 1. The tube condensate outlet of the first horizontal tube falling film evaporator 1 is connected to the condensate tank 5. The outlet of the condensate tank 5 is connected to the water collection tank of the second horizontal tube falling film evaporator 2 through the condensate pump B4. The outlet of the water collection tank of the second horizontal tube falling film evaporator 2 is connected to the spray feed inlet of the second horizontal tube falling film evaporator 2 through the spray pump B5. The separation section outlet of the first horizontal tube falling film evaporator 1 is connected to the tube-side inlet of the second horizontal tube falling film evaporator 2 via a solvent vapor pipe G4; the tube-side solvent outlet of the second horizontal tube falling film evaporator 2 is connected to the inlet of the solvent condenser 6; the outlet of the solvent condenser 6 is connected to the hot-side inlet of the solvent preheater 4 via a solvent discharge pump B3; and the hot-side outlet of the solvent preheater 4 is connected to the solvent outlet pipe G3.

[0010] Furthermore, the shells of the first horizontal tube falling film evaporator 1 and the second horizontal tube falling film evaporator 2 are horizontal structures, with the falling film heat exchange tubes arranged horizontally. The upper end of one tube box of the falling film heat exchange tube bundle is the tube-side inlet, and the bottom of the other tube box of the falling film heat exchange tube bundle is the tube-side outlet. The material spray nozzles are located above the falling film heat exchange tube bundle.

[0011] Furthermore, the first horizontal tube falling film evaporator 1 and the second horizontal tube falling film evaporator 2 have a separation section integrated at one end of their shells. The bottom of the separation section is connected to the bottom space of the shell, and a demister is provided at the upper outlet of the separation section.

[0012] Furthermore, the shell-side inlet of the second horizontal tube falling film evaporator 2 is connected to the saturated steam tube G5.

[0013] Furthermore, the water inlet of the condensate tank 5 is connected to the water supply pipe G6.

[0014] Compared to the prior art, the advantages or beneficial effects of the embodiments of this application include at least the following: 1. Adopting a new type of horizontal tube falling film evaporator with an integrated and compact structure, the separation section and heat exchanger are combined into one. The heat exchanger has a simple structure, saves piping and equipment space, and reduces equipment costs by more than 20%. Compared with traditional evaporation and distillation equipment, it is lower in height and can be placed indoors without the need for equipment foundation. It can be skid-mounted, and no on-site piping connection is required, reducing on-site installation workload and eliminating the risk of solvent leakage.

[0015] 2. After the water vapor condenses in the tube, it is discharged into the condensate tank. The material is sprayed onto the heat exchange tube shell through the nozzle and exchanges heat with the steam inside the heat exchange tube. The solvent evaporates after being heated and is discharged through the separation section. Compared with the traditional vertical tube falling film, the material forms a film on the outer wall of the heat exchange tube, which has a larger heating area and higher heat exchange efficiency.

[0016] 3. The falling film heat exchange tubes are arranged horizontally, which results in a large material heating area and high heat exchange efficiency. The evaporation of the material on the outer wall of the heat exchange tubes can be observed more intuitively through the sight glass, which facilitates timely adjustment of parameters and determination of the cleaning cycle.

[0017] 4. Water is used as a medium to introduce steam into the compressor, which indirectly concentrates the compounds in the organic solvent and recovers the high-purity organic solvent at the same time, avoiding the danger of solvent leakage and making on-site operators safer. Two preheaters are designed to recover qualified concentrate and waste heat from the solvent respectively, reducing the system's steam energy consumption. Compared with the traditional single-effect evaporation process, it saves more than 90% of steam energy consumption. 5. No condenser is required, and a large amount of circulating cooling water is not needed. It can achieve fully automatic operation and save on the consumption of public works. 6. The design involves spraying materials onto the outer wall of the heat exchange tube, which results in higher heat exchange efficiency compared to the self-flowing film formation on the inner wall of the heat exchange tube. The material circulation path is shorter, the residence time is shorter, and the production of qualified liquid is faster. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. The drawings are provided for reference and illustration only and are not intended to limit this utility model. Wherein: Figure 1 This is a flowchart of the horizontal evaporation and concentration system for organic solvents according to this utility model; Figure reference numerals: 1. First horizontal tube falling film evaporator; 2. Second horizontal tube falling film evaporator; 3. Concentrate preheater; 4. Solvent preheater; 5. Condensate tank; 6. Solvent condensate tank; Steam compressor M1; Feed pump B1; Concentrate discharge pump B2; Solvent discharge pump B3; Condensate pump B4; Spray pump B5; Organic solution feed pipe G1; concentrated liquid discharge pipe G2; solvent outlet pipe G3; solvent vapor pipe G4; saturated vapor pipe G5; water replenishment pipe G6; secondary steam pipe G7; compressed vapor pipe G8. Detailed Implementation

[0019] In the following description of this utility model, the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not mean that the device must have a specific orientation.

[0020] To make the technical means, creative features, achieved objectives and effects of this utility model easier to understand, the present utility model will be further described below with reference to specific illustrations. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0022] like Figure 1 As shown, the horizontal evaporation and concentration system for organic solvents of this invention includes a first horizontal tube falling film evaporator 1, a second horizontal tube falling film evaporator 2, a concentrate preheater 3, a solvent preheater 4, and a steam compressor M1. The shells of the first and second horizontal tube falling film evaporators 1 and 2 are horizontally oriented, with the falling film heat exchange tubes arranged horizontally. The upper end of one tube box of the falling film heat exchange tube bundle is the tube-side inlet, and the bottom of the other tube box is the tube-side outlet. A material spray port for the shell side is located above the falling film heat exchange tube bundle, and a collection tank is located below the falling film heat exchange tube bundle. The material sprayed by the first horizontal tube falling film evaporator 1 is concentrate, and the outlet of its collection tank is the concentrate outlet. The material sprayed by the second horizontal tube falling film evaporator 2 is condensate, and its collection tank is a water collection tank.

[0023] The first horizontal tube falling film evaporator 1 and the second horizontal tube falling film evaporator 2 have a separation section integrated at one end of their shells. The bottom of the separation section is connected to the bottom of the shell. Demisters are respectively installed at the upper outlet of the separation section.

[0024] The outlet of the organic solution feed pipe G1 is connected to the inlet of the feed pump B1. The outlet of the feed pump B1 is connected to the cold side inlet of the concentrate preheater 3 and the solvent preheater 4. The cold side outlet of the concentrate preheater 3 and the solvent preheater 4 is connected to the spray feed inlet of the first horizontal tube falling film evaporator 1. The concentrate outlet of the first horizontal tube falling film evaporator 1 is connected to the inlet of the concentrate discharge pump B2. The outlet of the concentrate discharge pump B2 is connected to the hot side inlet of the concentrate preheater 3. The hot side outlet of the concentrate preheater 3 is connected to the concentrate discharge pipe G2.

[0025] The compressed steam pipe G8 at the outlet of steam compressor M1 is connected to the tube-side inlet of the first horizontal tube falling film evaporator 1. The tube-side condensate outlet of the first horizontal tube falling film evaporator 1 is connected to the inlet of condensate tank 5. The water inlet of condensate tank 5 is connected to the water inlet pipe G6. The outlet of condensate tank 5 is connected to the inlet of condensate pump B4. The outlet of condensate pump B4 is connected to the water collection tank of the second horizontal tube falling film evaporator 2. The outlet of the water collection tank of the second horizontal tube falling film evaporator 2 is connected to the inlet of spray pump B5. The outlet of spray pump B5 is connected to the spray feed inlet of the second horizontal tube falling film evaporator 2. The shell-side inlet of the second horizontal tube falling film evaporator 2 is connected to the saturated steam pipe G5. The separation section outlet of the second horizontal tube falling film evaporator 2 is connected to the inlet of steam compressor M1 through secondary steam pipe G7.

[0026] The separation section outlet of the first horizontal tube falling film evaporator 1 is connected to the tube-side inlet of the second horizontal tube falling film evaporator 2 via solvent vapor pipe G4; the tube-side solvent outlet of the second horizontal tube falling film evaporator 2 is connected to the inlet of the solvent condenser 6, the outlet of the solvent condenser 6 is connected to the inlet of the solvent discharge pump B3, the outlet of the solvent discharge pump B3 is connected to the hot-side inlet of the solvent preheater 4, and the hot-side outlet of the solvent preheater 4 is connected to the solvent outlet pipe G3. Example

[0027] The main raw material is acetone, which has a boiling point of 56℃ and is flammable and volatile. It contains a dissolved non-volatile compound. The feed flow rate is 5t / h and the temperature is 20℃. After being pressurized by the feed pump B1, it enters the cold side of the concentrate preheater 3 and the solvent preheater 4. In the concentrate preheater 3, it exchanges heat with the compound concentrate on the hot side. In the solvent preheater 4, it exchanges heat with the evaporated and condensed acetone liquid. After heat exchange, the acetone reaches 45℃ and is sprayed through nozzles onto the outer wall of the heat exchange tubes of the first horizontal tube falling film evaporator 1. 4.5t of acetone is evaporated per hour. The acetone gas is discharged from the separation section of the first horizontal tube falling film evaporator 1 and enters the tube side, i.e., the heat exchange tubes, of the second horizontal tube falling film evaporator 2 through the solvent outlet pipe G3. It is condensed to obtain a high-purity acetone solution, which is discharged to the solvent condenser tank 6 for collection. The solution is then sent to the hot side of the solvent preheater 4 by the solvent discharge pump B3 for heat exchange.

[0028] This system concentrates non-volatile compounds from an initial concentration of 1.0% to 10% through evaporation, recovering valuable compounds and high-purity acetone. Compared to traditional single-effect evaporation and concentration processes, steam consumption is reduced by 90%, equipment height is reduced by more than 50%, direct contact with acetone is avoided, reducing the risk of flammability and explosion, the system performance is stable and reliable, and the consumption of circulating cooling water is reduced by 80%. Example

[0029] The main raw material is hexane, which has a boiling point of 69℃, is somewhat toxic, and is highly flammable. A non-volatile compound is dissolved in it. The feed flow rate is 3t / h, and the temperature is 30℃. After being pressurized by the feed pump B1, it enters the cold side of the concentrate preheater 3 and solvent preheater 4. After heat exchange with the compound concentrate and the evaporated and condensed hexane liquid, the temperature reaches 55℃. It is then sprayed through nozzles into the outer wall of the heat exchange tubes of the first horizontal tube falling film evaporator 1, evaporating 2.5t of hexane per hour. The hexane gas is discharged from the separation section of the first horizontal tube falling film evaporator 1 and enters the heat exchange tubes of the second horizontal tube falling film evaporator 2 through the solvent outlet pipe G3. The resulting high-purity hexane solution is condensed and discharged into the solvent condenser 6 for collection. Through this system, the initial concentration of the non-volatile compound is concentrated from 0.6% to 3.6%, recovering valuable compounds and high-purity hexane. Compared to traditional single-effect evaporation and concentration processes, steam consumption is reduced by 85%, equipment height is reduced by 30%, direct contact with hexane is avoided, reducing the risk of flammability and explosion, preventing hexane leakage, ensuring stable and reliable system performance, and reducing circulating cooling water consumption by 70%.

[0030] The above description is merely a preferred embodiment of the present utility model, showing and describing the basic principles, main features, and advantages of the present utility model. It is not intended to limit the scope of patent protection of the present utility model. Those skilled in the art should understand that the present utility model is not limited to the above embodiments. In addition to the above embodiments, the present utility model may have other implementations without departing from the spirit and scope of the present utility model. Various changes and improvements to the present utility model are also possible. All technical solutions formed by equivalent substitutions or equivalent transformations fall within the scope of protection claimed by the present utility model. The scope of protection claimed by the present utility model is defined by the appended claims and their equivalents. Technical features not described in the present utility model can be implemented by or using existing technology, and will not be elaborated here.

Claims

1. An organic solvent horizontal evaporation concentration system comprising an organic solution feed pipe (Gl), characterized in that: The outlet of the organic solution feed pipe (G1) is connected to the inlet of the feed pump (B1). The outlet of the feed pump (B1) is connected to the cold side inlet of the concentrate preheater (3) and the solvent preheater (4). The cold side outlets of the concentrate preheater (3) and the solvent preheater (4) are both connected to the spray feed inlet of the first horizontal tube falling film evaporator (1). The concentrate outlet of the first horizontal tube falling film evaporator (1) is connected to the hot side inlet of the concentrate preheater (3) through the concentrate discharge pump (B2). The hot side outlet of the concentrate preheater (3) is connected to the concentrate discharge pipe (G2). The outlet of the separation section of the second horizontal tube falling film evaporator (2) is connected to the inlet of the steam compressor (M1). The outlet of the steam compressor (M1) is connected to the tube inlet of the first horizontal tube falling film evaporator (1). The tube condensate outlet of the first horizontal tube falling film evaporator (1) is connected to the condensate tank (5). The outlet of the condensate tank (5) is connected to the water collection tank of the second horizontal tube falling film evaporator (2) through the condensate pump (B4). The outlet of the water collection tank of the second horizontal tube falling film evaporator (2) is connected to the spray feed inlet of the second horizontal tube falling film evaporator (2) through the spray pump (B5). The separation section outlet of the first horizontal tube falling film evaporator (1) is connected to the tube side inlet of the second horizontal tube falling film evaporator (2) via a solvent vapor pipe (G4); the tube side solvent outlet of the second horizontal tube falling film evaporator (2) is connected to the inlet of the solvent condenser (6); the outlet of the solvent condenser (6) is connected to the hot side inlet of the solvent preheater (4) via a solvent discharge pump (B3); and the hot side outlet of the solvent preheater (4) is connected to the solvent outlet pipe (G3).

2. The horizontal evaporation and concentration system for organic solvents according to claim 1, characterized in that: The shells of the first horizontal tube falling film evaporator (1) and the second horizontal tube falling film evaporator (2) are horizontal structures, the falling film heat exchange tubes are arranged horizontally, the upper end of one tube box of the falling film heat exchange tube bundle is the tube inlet, and the bottom of the other tube box of the falling film heat exchange tube bundle is the tube outlet; the material spray nozzles are located above the falling film heat exchange tube bundle.

3. The horizontal evaporation concentration system of organic solvent according to claim 2, characterized in that: The first horizontal tube falling film evaporator (1) and the second horizontal tube falling film evaporator (2) have a separation section integrated at one end of their shells. The bottom of the separation section is connected to the bottom of the shell. Demisters are provided at the upper outlet of the separation section.

4. The horizontal evaporation concentration system of organic solvent according to claim 1, characterized in that: The shell-side inlet of the second horizontal tube falling film evaporator (2) is connected to the saturated steam tube (G5).

5. The organic solvent horizontal evaporation concentration system according to any one of claims 1 to 4, characterized in that: The water inlet of the condensate tank (5) is connected to the water supply pipe (G6).

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