Ethylene desalted water (refined filler)-ethylene plant
Catalyst carrier (palladium, platinum, rhodium, etc. )-styrene, continuous reforming unit
Water purification and sewage treatment. Advanced treatment of water supply and sewage. Water quality treatment and protection of power plants. Boiler installation
Adsorption of NO, nitrogen oxides and other harmful gases-extraction of gold from boiler tail flue-carbon slurry method and heap leaching method are suitable for gold extraction.
Tail liquid recovery-gold mine waste utilization and environmental protection, cigarette filters, moisture-proof and odor-absorbing wood floors, automobile gasoline evaporation pollution control, preparation of various impregnating solutions, etc. For example, activated carbon can be used as a filler for producing motorcycle carbon cans and automobile carbon cans.
Application of 1 and activated carbon adsorption method in water treatment
Activated carbon adsorption is widely used in urban sewage treatment, drinking water and industrial wastewater treatment.
Granular activated carbon is often used to adsorb molecules, and its adsorption capacity determines its applicability, and its adsorption capacity is related to the pore size distribution of various carbon types. Take steam-activated peat-based, lignite-based and coconut shell-based powdered activated carbon as examples: peat-based activated carbon has micropores and mesopores, and granular activated carbon can be used for many purposes; Lignite-based carbon has many mesopores, granular activated carbon and larger mesopores, which provides excellent accessibility; Coconut shell-based granular activated carbon is mainly micropore, which is only suitable for removing low molecules.
Granular activated carbon activated by chemical substances is very porous, mostly in the range of micropores and mesopores, while the pore surface of activated carbon activated by steam and chemical substances is less hydrophobic and more negative. Take the crushed granular activated carbon as an example: Peat-based extruded activated carbon can be made into various varieties with different pore size distribution. All kinds of granular activated carbon with micropores are mainly used for gold recovery for gas-related purposes. Most species with both micropores and mesopores are used in liquid phase applications, such as adsorption of small and large molecular impurities in water purification.
Granular activated carbon based on crushed briquette has micropores and mesopores, which can be used for many purposes. Granular activated carbon based on lignite or coconut shell has the same micropore and mesopore structure as powdered carbon. The technical indicators of activated carbon are very important: the performance indicators of activated carbon products can be divided into physical performance indicators, chemical performance indicators of activated carbon and adsorption performance indicators of granular activated carbon. These three performance indexes play a very important role in the selection and application of activated carbon. The main physical properties of activated carbon are: shape, appearance, specific surface area, pore volume, specific gravity, mesh number, particle size, wear resistance, flotation rate and so on.
The main chemical properties of granular activated carbon are: PH value, ash content, moisture content, ignition point, uncarburized matter, sulfide, chloride, cyanide, sulfate, acid soluble matter, alcohol soluble matter, iron content, zinc content, lead content, arsenic content, calcium and magnesium content, heavy metal content, phosphate content and so on. The main adsorption performance indexes of activated carbon are: methylene blue adsorption value, iodine adsorption value, phenol adsorption value, carbon tetrachloride adsorption value, caramel adsorption value, quinine sulfate adsorption value, saturated sulfur capacity, penetrating sulfur capacity, water capacity, protection time of ethyl chloride vapor, ABS value, etc.
1) urban sewage treatment
Some organic substances in wastewater are difficult to be oxidized and decomposed by microorganisms or general oxidation methods, such as phenol, benzene, petroleum and its products, pesticides, detergents, synthetic dyes, amine compounds and many synthetic organic substances. After biochemical treatment, it is difficult to meet the discharge standard in water with high discharge requirements, which also seriously affects the reuse of wastewater and needs advanced treatment.
Activated carbon is widely used in advanced wastewater treatment because of its high adsorption capacity for organic matter, and has the following advantages:
① High degree of treatment. After advanced treatment with activated carbon, the BOD and TOC of municipal sewage can be reduced by 99% and1~ 3 mg/L. ..
(2) It has a wide application range and is effective for most organic substances in wastewater, including organic substances that are difficult to degrade by microorganisms.
(3) strong adaptability, strong adaptability to the change of water quantity and organic matter load, and stable treatment effect can be obtained.
(4) Granular carbon can be regenerated and reused, and the organic matter adsorbed in the regeneration process is burned without producing sludge.
⑤ Useful substances can be recovered, such as phenol-containing wastewater can be treated with activated carbon, and saturated activated carbon can be regenerated with alkali to recover sodium phenolate.
⑥ Compact equipment and convenient management.
2) Application in advanced treatment of drinking water
Activated carbon adsorption is generally arranged after sand filtration on the basis of conventional water supply treatment, and it can also be filtered with sand filtration materials to form a double-layer filter material or activated carbon filtration instead of sand filtration.
In the process of advanced treatment of drinking water by activated carbon adsorption, it is found that a large number of microorganisms grow on activated carbon filter material, which improves the effluent quality and prolongs its regeneration time. Therefore, an economical and effective biological activated carbon process for removing trace pollutants in water was developed, which included raw water (adding coagulant), clarification, filtration (adding ozone), activated carbon adsorption and finally effluent.
Step 2: Household use
Air purification: put activated carbon indoors to effectively absorb formaldehyde and xylene contained in the air.
Harmful substances (especially newly renovated houses),
Deodorization of furniture: Activated carbon can be coated on cabinets, drawers and refrigerators of newly bought furniture, and can also be put in shoes to deodorize.
Automobile odor removal: new cars generally contain a lot of harmful substances \ unpleasant pungent smell, which can be effectively removed with activated carbon.
history
The history of activated carbon application is as follows:
(1) BC 1550, Egypt had medical records;
(2) In 460-359 BC, the Greek doctor Hippocrates was used to treat epilepsy;
⑶1518 ~159 3 years, it was mentioned in Compendium of Materia Medica of Li Shizhen, China for treating diseases;
⑷ 1993 External use for ulcer treatment;
5] 1794 British state-owned sugar mills accelerated decoloration. The above examples all use charcoal, not activated carbon.
As an artificial material, activated carbon was invented in 1900 and 190 1. The inventor Rafael von Ostrico obtained the British patent B.P. 14224 (1900). British patent B.P. 18040( 1900) German patent G.P.136792 (1901).
He invented the method of carbonizing raw materials from plants with metal chloride or making carbon dioxide or water vapor react with carbonized materials to make activated carbon. 19 1 1 was first used in industrial production in a factory near Vienna. At that time, the product was powdered activated carbon with the trade name Epomit. In the same year, Norite was listed in the Netherlands; Carboraffin is sold in Czechoslovakia as 19 12. (yurts. U.S. Patent No.290656.
Historical stage
Looking back on the application history of activated carbon in the world in the past hundred years, it can be roughly divided into three stages:
(1) the first stage, from the early 20th century to the 1920s, is the embryonic stage:
(2) The second stage, from the mid-1920s to the growth stage;
(3) The third stage, from the middle of the 20th century to the end of the 20th century, is a development stage, which has developed to the stage of environmental protection application.
These three stages can use two historical events in the application of activated carbon. As a dividing line.
Historical event
The first major event was the application of activated carbon gas masks in World War I in the 1920s. This can be used as a boundary to divide the first stage and the second stage of the application history of activated carbon.
The main application of activated carbon in the early stage is that powdered carbon gradually replaces the original bone carbon in sugar industry. Particles that appeared in the First World War in the 1920s were widely used in gas masks. This is a brilliant page in the history of industrial chemistry. At that time, Norritt in the Netherlands and manufacturers and wholesalers in Czechoslovakia, Germany, France, Switzerland and other countries had set up joint companies, which shows that activated carbon budding is also a promising emerging industry in Europe.
With the application of gas masks, the history of activated carbon has entered the second stage, the market of activated carbon has been expanding, the application of adsorption and catalysis of activated carbon in refining, recycling and synthesis of many industries has been developed one after another, and activated carbon factories in the United States and other countries have been opened one after another. Activated carbon is considered as a "universal adsorbent", and its application has been expanding in the middle of the 20th century.
The second important thing is activated carbon deodorization. In the 1940s, hundreds of waterworks used activated carbon deodorization. This is the dividing line between the second stage and the third stage of the application history of activated carbon.
During the period of 1927, a foul smell accident of tap water occurred in Chicago Waterworks in the United States, which was unacceptable to residents. This is caused by the odor produced by phenol and chlorine used for disinfection in raw water. The same accident happened in waterworks in Germany and other places, all of which were solved by activated carbon.
Since then, with the increasing emphasis on environmental protection, government decrees have become increasingly strict. The consumption of activated carbon increased sharply, not only in water purification, but also in clean gas, which made the environmental protection industry a major application of activated carbon in the second half of the 20th century. Thus, the history of activated carbon has entered the third stage, that is, the development stage.
The application history of activated carbon in China can be divided into three stages:
1. The first stage was before the 1940s. China's pharmaceutical and chemical industries use a lot of activated carbon, and all of them use imported goods, such as Carboraffin brand activated carbon.
2. In the second stage, domestic activated carbon was introduced in the early 1950s. 195 1 Shenyang, Fushun single-tube furnace factory, Qingdao reverberatory furnace smoldering factory, followed by Shanghai electrothermal activation factory, followed by zinc chloride activation factory, 1958 Fujian, Hangzhou, Guangzhou, Yantai and Northeast China. 1966, a mud activation plant was established in Taiyuan. In addition, there are many factories, such as converters and grate furnaces. The total production capacity soared from 30 to 50 tons of 195 1 to nearly100000 tons in the 1980s.
Production and application promote each other, and the application scope of activated carbon expands rapidly. From the original single general carbon to a variety of special carbon, such as water purification carbon, sugar carbon, essence carbon, grease carbon, gold carbon, carrier carbon, medicinal carbon, injection carbon, reagent carbon and so on. It shows that the application of activated carbon has increased rapidly due to the vigorous development of domestic economy, and the export volume has increased due to the expansion of output and the reduction of cost. The application of activated carbon in China has not only developed in the domestic market, but also entered the international market.
3. The third stage is from 2003 to the present; Activated carbon is used for decoration pollution control. Using advanced pore-forming technology, activated carbon has a pore structure that matches the molecular size of indoor harmful gases, and is specially used to adsorb all harmful gases and planktonic bacteria such as formaldehyde, benzene series, ammonia and radon in the air. It has the comprehensive functions of odor absorption, detoxification, deodorization, dehumidification, mildew prevention, sterilization and purification. Effectively remove indoor environmental pollution, successfully applied to decoration pollution control. There are many household activated carbon in major markets and supermarkets. Activated carbon has entered thousands of households and become a healthy and fashionable environmental protection product.