Does carbon dioxide purification need to enter the chemical industry park?

At present, CO2-rich gas sources such as oil field shift gas, food fermentation gas, lime pool gas, blast furnace gas, converter gas flue gas and methanol cracking gas (as shown in the attached table) all contain impurities such as sulfide, nitrogen oxides, H2O and hydrocarbons, which are required to be used as beverage additives or chemical raw materials. The key issues in the development of CO2 purification technology are low impurity content, low temperature distillation, membrane separation and solvent absorption pressure swing adsorption.

Schedule CO2 gas source and content

Carbon dioxide gas source

Content (percentage)

1

Gas field gas

80~90

2

Ammonia synthesis by-product gas

98~99

three

By-product gas from petroleum refining

98~99

four

By-product gas of fermentation industry

95~99

five

Ethylene glycol will produce by-product gas.

9 1

six

Steelmaking by-product gas

18~2 1

seven

Coal-fired boiler flue gas

18~ 19

eight

Combustion gas of coke and heavy oil

10~ 17

nine

Gas combustion flue gas

8.5~ 10

10

Lime kiln tail gas

15~45

3. 1 low temperature distillation

Because of its large equipment, high energy consumption and poor separation efficiency, this product is suitable for large-scale production and direct injection of sulfur-containing CO2 products into oil wells to improve oil recovery.

3.2 Membrane Separation Solvent Absorption

Membrane separator has the advantages of simple equipment, convenient operation and low energy consumption, and it is an energy-saving gas separation technology that is developing rapidly in the world today. Membrane separation technology is difficult. High purity CO2 must be combined with solvent absorption. The former is extremely complicated for the roughing machine to do fine separation.

3.3 Pressure swing adsorption (PSA)

Pressure swing adsorption has the advantages of simple process, low energy consumption, strong adaptability, high degree of automation, advanced technology, economy and rationality.

Performance of CO2 physical adsorbent: It has stronger adsorption capacity than other gases. Pressure swing adsorption (PSA) uses the difference of adsorption capacity to achieve the purpose of separating and purifying the mixed gas (CO2) with the same purity.

The mixed gas containing CO2 first enters the pretreatment process to remove adsorbents with strong adsorption capacity such as sulfide, nitrogen oxides, H2O and higher hydrocarbons in the mixed gas, and then enters the pressure swing adsorption process to adsorb CO2 gas with high phase purity to meet industrial needs, and the liquid and solid CO2 products with high purity are purified through the purification process.

Sichuan Science and Technology Co., Ltd. (formerly Southwest Research and Design Institute of Chemical Industry, Ministry of Chemical Industry) 1988 1989 successively contributed to the purification of shift gas carbon dioxide in lime cellar ammonia plant. The first set of pressure swing adsorption industrial device for purifying carbon dioxide was built in Jiangmen Nitrogen Fertilizer Plant, Guangdong Province in June 19897, producing food-grade carbon dioxide12t/d. Due to the quality problem of carbon dioxide, the pressure swing adsorption device of this plant was built in Hong Kong and Macao, Guangdong Province. In addition to providing 12 tons of food-grade carbon dioxide to the market, due to the removal of shift gas carbon dioxide by pressure swing adsorption device, the amount of liquid ammonia in decarbonization workshop decreased correspondingly, and the output of commercial liquid ammonia increased. According to the operation of Jiangmen plant, the output of liquid ammonia in nitrogenous fertilizer plant is 5t/ D, and it is planned to build a new pressure swing adsorption CO2 purification plant, which will increase the promotion of two products and two effects. In addition, in 2000, the company built a set of CO2 purification device for lime pool gas in Zhejiang Juhua Calcium Carbide Factory, which is difficult to solve the mixed gas problem of lime pool gas raw materials. The nitrogen oxides were desalted, so that the product basically met the requirements of Couler standard (nitrogen oxides < 5 mg/m3). The company has provided 30 sets of pressure swing adsorption CO2 purification devices for various manufacturers, producing CO2 products with the same purity of 96.00% ~ 99.99%, mainly including

4 Market prospect

CO2 from developed countries is widely used in various fields in the North American market, including food freezing and refrigeration, 40% beverage carbonation, 20% chemical product production, 10% metallurgy and 10% Italy. At present, the market includes beverage carbonation, 20% wastewater treatment, 23% food freezing and 13% welding.

At present, CO2 consumption:18kg/a Yili 2.2kg/a In North America, foreign beverage companies MEBO Pepsi and Coke have settled in.

Non-rapid development ratio of domestic beverage industry: The domestic consumption of CO2 in Guangdong Province is about 50,000 tons/year, and the market demand is expected to increase to about 80,000 tons/year in the next five years. It is estimated that the average growth rate of domestic carbon dioxide market is 65,438+00%, which indicates that the higher the quality requirements of domestic carbon dioxide products, the food-grade carbon dioxide production becomes a hot issue.

With China's entry into WTO, CO2 gas shielded welding machines are continuously introduced, and the market demand for CO2 is increasing. At the same time, the bottom blowing of steelmaking furnace is changed from high nitrogen to cheap CO2 gas, and the popularization of nanotechnology is bound to bring CO2, the necessary raw material gas of nanotechnology, to the first choice of CO2 market.

CO2 has been used as an intermediate catalyst in the chemical industry, and the examples of cyclized lactones, carboxylic acids, formamide, hydrocarbon compounds and polymers have not been widely promoted in the domestic market. The main reason is that CO2 splashing requires high temperature and high pressure or the use of catalysts for reaction. Developed countries have invested their efforts and resources to produce CO2. In the early 1980s, some countries invested 23 billion yuan, trying to establish an independent working system of carbon source using solar energy for CO2 storage. There is every reason to believe that long-term alternatives to coal and liquefied petroleum gas will benefit from it.

The structure of carbon dioxide.

, supercritical fluid (supercritical fluid)

1. Overview

With the change of environmental temperature and pressure, any species

Mass exists in three states-gas phase, liquid phase, solid phase and three phase.

The equilibrium point is called the triple point. Liquid and gas are homogeneous.

The equilibrium point is called the critical point. Critical point temperature and pressure

This force is called critical temperature and critical pressure, as shown in figure 1, as above.

The critical point of matter is the same as pressure and temperature.

supercutical fluid

Refers to a fluid whose temperature and pressure are higher than its critical point.

Prepare supercritical fluids such as carbon dioxide, ammonia, ethylene, propane, propylene and water. The object is in a supercritical state.

Because of the different properties of gas and liquid phases, the boundary state is very clear.

Don't, the so-called "supercritical fluid"

2. Development history of supercritical fluid

Supercritical fluid has the special ability to dissolve its substances, which was first published by Cagniard, 1822.

Material criticality phenomenon, and 1879, that is, HannayHogarth, found that organic salts can be quickly.

When supercritical ethanol is dissolved, it can be crystallized immediately under reduced pressure. Due to technology and equipment, it is difficult.

Figure 1. Three-phase diagram and critical point diagram of an object.

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In 1930s, two scientists named PilatGadlewicz used liquefied gas to extract "compounds".

1950 generation, the United States and the Soviet Union carried out supercritical propane to remove heavy oil tar and gold.

Genus, nickel, vanadium, etc. In order to reduce the poisoning loss of Duan Lian cracking catalyst, which involves this consideration.

It's not entirely practical. 1954Zosol Experiments prove that supercritical carbon dioxide extraction is used to extract oil.

Oil and fat. Supercritical fluid separation Ji Shen, 70th generation.

During this period, Stahl and others made a breakthrough in the research of "supercritical" high-pressure experimental device.

The new technology of carbon dioxide extraction has made substantial progress only from the research and application of technology; 1973 and

1978 the special solubility of supercritical carbon dioxide was once again affected by the second energy crisis.

The industry attaches great importance to. 1978, and supercritical carbon dioxide is established as the extractant in Europe.

Pure technology, processing tens of millions of tons of products in food factories, such as coffee with supercritical carbon dioxide removal.

Coffee beans and beer flavor extracted from bitter flowers.

Supercritical fluid extraction technology is a new technology in chemical industry in recent 30 years, which has aroused great interest.

The field of reaction separation and purification has been widely and deeply studied, and progress has been made in medicine, chemical industry and food.

Products and environmental protection fields are too numerous to mention.

3. Supercritical fluid characteristics

Supercritical fluid has similar gas diffusivity and liquid solubility, and has low viscosity and low surface area.

As shown in table 1, the surface tension characteristics enable supercritical fluid to quickly penetrate into microporous materials.

The extraction rate used for extraction is faster than that of liquid, especially the solubility varies with temperature and pressure polarity.

Change.

Supercritical fluid extraction makes use of the relationship between the solubility of supercritical fluid and its density, that is, the benefit.

It is carried out under the influence of pressure and temperature on the solubility of supercritical fluid. The substance is in a supercritical state,

Its nature is in a single-phase state between liquid and gas. The density of liquid is similar and the viscosity is higher than that of gas.

The volume is obviously lower than that of liquid, and the diffusion coefficient of liquid is 10 ~ 100 times, so the material has stronger permeability.

Strong solubility, can extract some substances.

In supercritical state, supercritical fluid is in contact with the substance to be separated, so its selectivity depends on.

Polar, high boiling point and low boiling point extraction. Same density and polarity as supercritical fluid.

The dielectric number increases with the increase of pressure in the closed system, and the same polarity is boosted by a predetermined program.

Step-by-step extraction is carried out, and the extracted substances in each pressure range can be single.

By controlling the conditions and mixing in a good proportion, with the help of decompression, the temperature is raised and lowered to reach the supercritical state.

The fluid becomes ordinary gas or liquid, and the extracted substance is completely separated by itself, thus achieving the purpose of separation and purification.

The basic principle of extraction and separation is to combine supercritical fluid extraction and separation.

4. See Supercritical Fluid

In principle, any substance should be able to become supercritical, the critical pressure of some substances.

Phase density ρc (g/cm3) viscosity (Pa·s) diffusion coefficient (cm2/s)

Gas10-310-510-1

Supercritical fluid 0.1~ 0.510-4 ~10-510-3.

Liquid10-310-310-5

Table 1. Table of Basic Properties of Typical Supercritical Fluids, Liquids and Gases in Environmental Safety Institute of Industrial Research Institute

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The critical temperature is too high, see the summary table.

See key data sheet 2.

Second, supercritical carbon dioxide (supercritical carbon dioxide)

1. Overview

The temperature of carbon dioxide is higher than the critical temperature Tc=3 1.26℃, and the pressure is higher than the critical pressure Pc=72.9atm.

State, property changes, its density is close to liquid, its viscosity is close to gas, and the diffusion coefficient of liquid is 100.

Times, with amazing solubility. Using dissolved substances to extract their effects,

And has broad application prospects. At present, supercritical carbon dioxide has been widely studied in fluids, among which

Several characteristics:

The critical temperature of (1)CO2 is 3 1.26℃ and the critical pressure is 72.9atm, so the critical conditions are easy to reach.

(2)CO2 is splash, toxic in color and taste, and safe.

(3) low price, high purity and easy availability.

2. Supercritical fluid extraction -CO2)

The so-called supercritical extraction of carbon dioxide has been dissolved by pressure, temperature and pressure in supercritical state.

Agent, its extremely high solubility to extract substances that are easy to extract, some points for attention about extraction:

(1) dissolution

In supercritical state, the solubility difference between CO2 and solute, and the polarity of solute,

Boiling points are closely related, and the general rule is: lipophilic, low boiling point.

104KPa (about 1 air pressure) extraction, volatile oil, hydrocarbons, esters, ethers, epoxy compounds and

Plant solid perfume, eucalyptol, thymol, hops low boiling point ester, etc.

The more polar groups (-OH, -COOH, etc. ), the more difficult it is to extract.

The extraction pressure of amino acids is 4× 104KPa. In addition, the more compounds, the more difficult the extraction.

Take; It is easy to extract in the range of 200 ~ 400, and some of them are small in amount and volatile.

Even directly extracting with CO2 liquid; High content of substances (protein, gum wax, etc. ) it's hard.

Carbon dioxide extraction.

(2) Features

Several extraction technology using supercritical carbon dioxide as extraction tool

trait

A. Toxic gases with color and odor in supercritical CO2 fluid state are extracted, separated and sorted.

Critical temperature critical pressure critical density critical temperature critical pressure critical density

H2-239.9 12.8 0.032 CF3Cl 28.8 38.7 0.579

N2- 147.0 33.5 0.3 14 NH3 132.3 1 1 1.3 0.235

Xe16.6 57.71.10 methanol 240.0 78.5 0.272

Carbon dioxide 31.26 72.9 0.468 ch3cn274.7 47.7 0.237

C2 h6 32.3 48.2 0.203 H2O 374.2 2 18.3 0.3 15

CF3H 25.9 47.8 0.526℃ atm g/cm3

Table 2. See ITRI Environmental Safety Key Data Sheet.

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No solvent residue, effectively avoiding the toxic solvent residue under the traditional solvent extraction conditions.

To prevent the extraction process from poisoning the environment and polluting species.

And environmental protection extraction technology.

B, the extraction temperature is low, the critical temperature of CO2 is 365,438 0.265℃, and the critical pressure is 72.9atm.

Effectively prevent heat-sensitive oxidation and escape reaction, and completely retain substances.

Sex; It has high boiling point, low volatility, easy pyrolysis and its boiling point temperature.

Excerpts

C, pul out that clutch 2, wherein the supercritical fluid filled with dissolve carbon dioxide flows through the separator.

Due to the pressure drop, CO2 and extract quickly separated from each other (gas-liquid).

From) immediately, in the process of phase change, it is necessary to collect solvents for easy operation;

Only the extraction efficiency is high, the energy consumption is low, and the cost is saved, which conforms to the trend of environmental protection and energy saving.

D, the extraction operation is simple, and the parameters of the extraction range can be adjusted under pressure and temperature. critical point

In the vicinity, slight changes in temperature and pressure will lead to significant changes in CO2 density, which will lead to waiting.

The solubility of the extract changes, and the purpose of extraction can be achieved by controlling the temperature or pressure.

Fixed pressure, changing temperature and material separation; Fixing temperature, and reducing pressure to obtain extract.

Leave; Short process flow, low consumption, really friendly to the environment, extraction.

Liquid CO2 recycling, waste CO2 emissions, leading to the greenhouse effect! real

"Green" production technology.

E, changing the polarity of the supercritical fluid, fixing the temperature condition, changing the pressure or increasing an appropriate pressure.

The suitable entrainer is to extract substances with the same polarity, and the selection range is wide.

(3) affecting the extraction of elements

Several problem affecting supercritical carbon dioxide extraction-supercritical carbon dioxide density,

Entrainer, particle size, volume, etc.

A. density

The strength of solvent is related to the density of supercritical fluid. When the temperature is constant, the density (pressure) increases.

Addition increases the solvent strength and solute solubility.

B. entrainer

It is suitable for polar solvent extraction of supercritical fluid solvent, which is beneficial to

Selective extraction limits its polarity to solute applications. Some liquid

Add a small amount of entrainer to change the polarity of the solvent. Extracting supercritical fluid.

By adding entrainer, carbon dioxide is suitable for more polar compounds.

Pressure (about equal to 100 air pressure), using ethanol with the same concentration as entrainer, study

Three Tibetan medicines, Ganoderma lucidum, were extracted and supercritical carbon dioxide was added as entrainer.

Create a solvent to meet the extraction conditions and greatly improve the yield. Precious medicinal materials

The extract has great industrial value. The solvent is ethanol, urea, acetone,

Alkanes and water, etc.

C. particle size

Particle size affects the extraction rate. Generally speaking, the particle size is favorable for supercritical two.

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Carbon dioxide extraction.

D. fluid volume

The structure of the extract is related to the required supercritical fluid volume. Kejiajia

50 grams of lutein and carotene were extracted at 40℃, 68.8MPa and 40℃.

The 50% yield of lutein requires 2. 1L supercritical carbon dioxide; 95%

According to the calculation, the output needs 33.6 liters of supercritical carbon dioxide and carotene dioxide.

The solubility of carbonization only needs 1.4L, that is, the yield reaches 95%.

3. The main application scope of supercritical carbon dioxide technology

Carbon dioxide is a widely used supercritical fluid, which is mainly non-toxic.

Low critical temperature and low price. The research field of near attention is mainly functional.

Extraction, fiber dyeing technology, semiconductor cleaning, special drug particle production, dry cleaning technology, chemistry

Reaction and supercritical fluid rice cleaning technology, etc. See supercritical carbon dioxide in various industries.

serviceable range

(1) food industry

A vegetable oils (soybean oil, castor oil, palm oil, butter, corn oil, rice bran oil and wheat germ)

Oil, etc. ) extraction

B. Extraction of bio-oil (fish oil, cod liver oil and various aquatic oil); Food raw materials (rice, flour, eggs)

degrease

C separation and purification of lipid mixture (glyceride, fatty acid, lecithin, etc.). )

D. Decolorization and deodorization of oils and fats

E. extract that fragrance of the plant pigment.

F. coffee, black tea, coffee removed

G. hops extract

H. concentration of fermented alcohol

(2) Pharmaceutical and cosmetic industries

A. extracting higher fatty acids (EPA, DHA, dehydroascorbic acid, etc.). ) from fish oil

B, extracting higher fatty acids (gamma-linolenic acid, etc.). ) from plants or bacteria.

C. Pharmacodynamic extraction (alkaloids, flavonoids, fat-soluble vitamins, glycosides, etc.). )

D. extraction of spices (biological spices, plant spices, etc. )

E. Extraction of cosmetic raw materials (skin care agent, surfactant, fatty acid ester, etc. )

F. removal of nicotine from tobacco.

(3) Chemical industry

Look at the application of supercritical carbon dioxide technology, including traditional industrial dry cleaning and fiber dyeing.

Technology, chemical reaction semiconductor cleaning technology and other high-tech industries.

The traditional dry clean industry is faced with that organic solvent perchlorotoluene it use,

Health and environmental hazards are pressures that many major related industries have never sought.

In fact, the dry cleaning equipment using supercritical fluid technology has been 1999.

The United States has set up a business store, and the unit price of a set of equipment is about 75 thousand to 50 thousand dollars.

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The industrial application of supercritical fluid proves that supercritical carbon dioxide, energy efficiency and traditional migrant workers

Other cleaning applications include metal parts cleaning and commercial dishwashers.

Use ordinary household cleaning equipment.

Supercritical carbon dioxide is used to replace the existing organic solvent dyeing technology in environmental protection and wastewater treatment.

Principle and manufacture are not advantages. Because supercritical carbon dioxide fluid, its basic characteristics

It is close to gas, so it is used to replace machine fluid in polyester fiber dyeing process.

It is said that the problems of waste discharge include the reduction of industrial water consumption and the harm of industrial waste.

Restore. Economic advantages include increasing output, reducing energy consumption and fiber dyeing.

The application of technology industrialization, enhancing the economic competitiveness of dyeing technology, and the progress of textile industry

Improve the operation process, reduce waste water discharge and dyeing room, machine room, energy,

Environmental protection and other aspects have made progress. Supercritical fluid dyeing technology is more economical.

More economical and environmentally friendly new technology. Institute of Chemical Engineering, Institute of Supercritical Fluid Dyeing Technology

Force, leading the chemical industry into a new cradle of green generation.

Supercritical carbon dioxide provides another choice for traditional organic solvents. In addition to environmental protection,

In addition, the temperature, pressure, flow rate, reactant concentration and other reaction variables are controlled to carry out the reaction.

The control itself is easier, and the reaction selectivity increases due to the easy control of the reaction operation.

With the output, the reaction itself can be carried out in less time and space, and the equipment cost is invested.

Reduce the contribution, because the solubility of some reactants in carbon dioxide fluid is greater than that of substances,

The main technical overcoming point lies in the shape of emulsified particles and their carbon dioxide fluid.

Speed and Surface Application, Dupont North Carolina, with an investment of 4000 yuan.

The case of $10,000 investment in a new research factory has attracted attention, and the main research direction is to take advantage of Lin Chao.

Carbon dioxide is used as a reaction solution to produce fluoropolymer.

The etching residue of photoresist on semiconductor chip has no seed effect.

In addition, it is generally necessary to cooperate with several devices, such as plasma ashing.

Ashing) and wet or dry cleaning can meet the product quality requirements, and now wet cleaning.

Using corrosive sulfuric acid, hydrogen peroxide or organic solvent to mix, some traditional products

The waste liquid produced by measuring machines has a polar impact on the environment, including the famous Los under the US Department of Energy.

Alamos Laboratory and its research institutions actively develop and utilize supercritical carbon dioxide.

Carbonization technology, except the photoresist of semiconductor wafer, uses supercritical fluid technology.

Treatment, energy efficiency single cleaning tank, semiconductor wafer residual impurity cleaning, by

The surface tension viscosity of supercritical fluid is not low, and the solvent can be cleaned quickly and efficiently.

It has a fine structure below 0. 18μm, except photoresist and its derivatives, as above.

Energy can reduce the dosage of harmful solution, reduce the production of wastewater, and more importantly, simplify the preparation.

Processing and increasing output.

Foreign and foreign chemical industries began to use supercritical carbon dioxide extraction technology to reduce production.

Process pollutant generation

A. petroleum residue oil leaching

B. crude oil is collected and lubricating oil is recovered.

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C. hydrocarbon separation and extraction of coal liquefied oil

D. Treatment of waste liquid containing refractory substances

(4) Medical industry

The application of supercritical carbon dioxide in pharmaceutical industry far exceeds its industry. Supercritical carbon dioxide

Carbonization has three applications in the field of pharmaceutical industry-drug extraction of physical substances and drugs.

pharmaceutical analysis

A. Drug extraction of physical substances

(a) concentrated sardine oil and flat algae EPADHA, comprehensive utilization of seaweed resources for innovation.

Way.

(b) extracting egg yolk phosphate from egg yolk

(c) extracting phospholipids from beans.

Extracting β -carotene from rotten tomatoes.

B. Medicine

Supercritical fluid crystallization technology is based on the solubility, temperature and pressure of supercritical fluid.

Ultrafine particles are prepared by force-sensitive characteristics, and their GAS anti-solvent range (gas) is used for physical objects.

Quality treatment. Gas method refers to dissolving carbon dioxide under high pressure to expand organic solvents.

Energy accumulation is obviously reduced, solubility is reduced, and dissolved substances are crystallized or precipitated.

Cheng. app; application

(a) The solution of carbon dioxide, insulin and dimethyl sulfoxide passes through a special nozzle, and the top enters the precipitation.

Device, high-pressure mixed-flow precipitator, insulin crystal aggregation bottom

Screening program.

(b) Improve the utilization rate of insoluble substances.

(c) parenteral administration, with less damage to hair (transdermal absorption by pulmonary administration)

System).

C. Drug analysis

Supercritical fluid in chromatography technology

The supercritical fluid chromatography, Figure 2, and

High speed, high efficiency, strong selectivity and high efficiency.

High efficiency, low cost and low consumption,

Low cost and easy control of conditions and pollution.

Products, etc. , suitable for difficult volatilization and easy pyrolysis.

Rapid analysis of substances. Supersonic for experts.

Analysis of Coffee and Ginger by Critical Fluid Chromatography

Powder, pepper, hops, hemp, etc.

Full supercritical technology is not only used in plant extracts in pharmaceutical industry, but also used in

The more extensive, the more promising.

D. Production of special granules

Application of pharmaceutical industry, manufacture of special drug particles, modern supercritical fluid technology.

Figure 2. Chromatogram of supercritical fluid.

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Industrialization, application of important technologies, development of supercritical fluid technology, and energy efficiency control of drug particle shape.

For solid particles or particles with loose internal structure, polar or nonpolar and particle size

Particles of 50 nm and 50 microns can be produced, and some application technologies of particle shape are mainly three.

Category: Rapid expansion of supercritical solution (RESS), reverse dissolution of gas or supercritical fluid.

Gas or SAS and compressed anti-solvent precipitation (PCA). The application products of this technology include

Swallowing powder, intravenous solution powder, etc. Current types of applied research.

Non-industrial equipment needs a water tank of about 50 liters, that is, design.

Product function equipment is more in line with the actual needs, the main problem is that the equipment must

Good manufacturing practices (cGMP) must be met, and these requirements may have to include molecular oxygen.

Quality and source of carbonization, requirements of process and raw materials, factory software and hardware.

Provisions, including process standardization, quality control and quality assurance system, operating procedures and control software.

And hardware certification, raw materials and equipment quality requirements, pressure vessel inspection, equipment cleaning operations.

Regulations and controllers should be calibrated, and some regulations are aimed at equipment manufacturers and users.

In terms of product manufacturers, it is not important, and the investment cost must be estimated.

Third, supercritical fluids are not expected.

At present, the research and application of supercritical fluid extraction granulation technology are developing vigorously, and the technical development should

The application scope includes: extraction, separation, cleaning,

Coating, dipping, particle formation and inversion.

Germany and the United States are already in the leading position, in medicine, chemical industry, food, light industry,

Environmental protection and other aspects have been studied, and the industrial supercritical fluid equipment is 5000 l ~10000 l.

Scale, which has successfully developed a supercritical chromatography analyzer, Taiwan Province Yiwuwang Grain Company uses supercritical.

Carbon dioxide extraction technology is used to extract and remove pesticide residues and heavy metals in rice.

Keywords recent research field, main function extraction, fiber dyeing technology,

Semiconductor cleaning, production of special drug particles, etc. For fluid applications, carbon dioxide, water and carbon dioxide.

There are three kinds of alkanes. Because of its safety, carbon dioxide is not used as a supercritical fluid.

Persistence plays an important role. Supercritical water application, expected wave mainstream. Some food

Compared with carbon dioxide, the application of propane is paid more attention.

At present, the research focus of supercritical fluid extraction has shifted, with high purity.

Study on extracting valuable products by supercritical fluid countercurrent extractive distillation. Supercritical conditional reaction

Research focus, especially various reactions under the conditions of supercritical water and supercritical carbon dioxide, and so on.

Supercritical fluid technology is widely used, except for product extraction and mechanical synthesis.

Environmental protection, material processing, pigment printing and dyeing, biotechnology and medicine. Close supercritical fluid technology

Basic theoretical research has been strengthened, and I pay more attention to it.

Supercritical fluid technology is very important in the modernization of medicine, and it is necessary to take into account the extraction of raw materials.

The development and utilization of compound drugs and new drugs, or the improvement or secondary development of the existing production technology of famous drugs; increase

The application of strong analytical supercritical fluid extraction or supercritical chromatography in drug analysis has broken the traditional analytical methods.

; Supercritical fluid crystallization technology and its ultrafine particle preparation should be strengthened when applied to new drug formulations.

References:

I suggest reading more.

Others can only be used for reference, which is meaningless.