Charcoal is widely used in the metallurgical industry.
As a restorer.
Charcoal is widely used in the metallurgical industry as a reducing agent. Its composition is unique – from any other reducing agents charcoal is characterized by a complete absence of sulfur and phosphorus, the presence of which worsens the properties of the recovered materials. Charcoal has high electrical resistivity and reactivity, purity. It is necessary for the smelting of lanthanides, rare and valuable metals, such as manganese. It is also used as a coating flux in the smelting of some types of bronze and brass, Nickel alloys (nickel, nickel silver).
Exclusively charcoal is used in the production of crystalline silicon for the electronic industry. In this case, the reducing agent must be absolutely clean to ensure the dielectric properties of silicon. High purity requirements are also imposed on silicon used in the smelting of siliceous alloys. In this case, mainly charcoal is used for the production of silicon.
Cementation is the process of saturation of the upper metal layer with carbon while the inner layers remain unchanged. Due to this, the product is more resistant to the load on the abrasion and fracture. The most popular cementation solid carburetor. The parts are placed in a metal box, pour them with a mixture of charcoal (75 — 85% of the volume) with activators such as barium carbonate (BaCO3) or soda (Na2CO3). The box is tightly closed, coated with refractory clay and placed in an oven with a temperature of 900 — 950 degrees. After prolonged exposure (12 — 15 h) box is removed, cooled and removed from the parts. Then all parts are subjected to hardening with low tempering.
Example of parts that have passed cementation
Protection against decarburization
For products whose surfaces are not polished after heat treatment, carbon burnout and scale formation is unacceptable. Often in this case, salt baths are used. Salt baths are a metal body with refractory lining. As salts in baths widely used potassium and sodium nitrate, as well as table salt. Heating of baths is most often carried out by electric current. Salt baths when heated do not allow the metal to oxidize, but do not protect against decarburization. Therefore, in the production of their deoxidize at least twice a shift. Salt baths, working at temperatures of 760-1000 degrees Celsius, very effectively deoxidized charcoal. For this purpose, the glass having a plurality of holes over the whole surface, filled with dried coal of wood, covered with a lid (so coal is not surfaced) and after heating is lowered to the bottom of the salt bath. First, there is a significant number of flames, then it decreases. If during the change in this way three times deoxidize bath, the heated products will be fully protected from decarburization.
Approximately 25% of the charcoal produced has a fine and pulverized fraction. This fraction is not in demand at consumers as at burning access of oxygen to it is difficult. However, the fine fraction is widely used in briquetting. In this technology, charcoal dust is mixed with a binder(usually with starch paste), and then pressed and dried. What is good briquettes of charcoal? They tolerate transport and storage, have a high calorific value(not less than 8000 kcal/kg), burned completely, not very, and decaying into ash (the ash content of high quality charcoal briquette is not more than 5%). Briquette is widely used in barbecues, kebabs, grills, fireplaces.
Activated coal is an adsorbing agent. The main option of activated charcoal is BAU-A (Birch activated coal — brand “A”). It has a large surface activity and high sorption capacity. The essence of activation consists in opening the pores that are in the carbon material in the closed state. This is done either thermochemically (the material is pre-impregnated with zinc chloride, potassium carbonate or some other compounds, and heated without air access), or by processing with superheated steam or carbon dioxide or a mixture of them at a temperature of 800-850 °C.
A classic example of the use of activated charcoal is associated with its use in personal respiratory protection. Gas mask developed by N. D. Zelinsky, saved many lives of soldiers in the First world war after the use of chemical warfare agents by Kaiser Germany. By 1916, it was adopted by almost all European armies.
The percentage of gastrointestinal diseases in cattle reaches 60-90% . It is connected with infringement of technology of keeping and feeding animals, as well as the imperfection of the natural protection of the body from the effects of adverse environmental factors. Gastrointestinal diseases of calves cause huge damage to livestock due to the wide prevalence, high morbidity, high costs of treatment, reduction of productive qualities and breeding value of animals.
In animal husbandry, various types of sorbents (clay materials, cyolites, verminites, bentonites and various polymeric substances) are used for the prevention and treatment of gastrointestinal disorders, but of particular interest is the use of activated charcoal for the prevention and treatment of animal poisoning by mycotoxins and other harmful substances.
A method for preparing an active charcoal feed additive: a finely fractionated activated charcoal is introduced into the mixer, then, with constant stirring, an estimated amount of an aqueous solution of a coniferous extract is added to obtain a homogeneous mass. After that, kept for 10-12 hours at room temperature and packaged.
This method makes it possible to obtain an active charcoal feed additive for the prevention and treatment of gastrointestinal diseases of farm animals with good technological characteristics and the lack of traceability of the finished product during transportation and storage. In particular, in growing pigs, it is well-known feed additive «“Protosorb”» on the basis of charcoal.
To evaluate the influence of activated charcoal supplements was formed 4 in the control group. Activated charcoal was added to the feed of the 1st group of poultry at a dose of 200 grams per 1 ton of feed, the amount of the second experimental group of poultry was 400 grams per 1 ton of feed, and in the third — 800 grams per 1 ton of feed. The fourth group was a control and activated charcoal additive with food did not receive.
The results of studies allow us to conclude that the change in clinical and hematological parameters within the physiological norm is faster in chickens of the second experimental group with the introduction of activated charcoal additive in the diet at a dose of 400 g per 1 ton of finished feed.
The use of activated charcoal feed additive in different dosages led to a marked increase in the level of phosphorus in the blood serum, which is especially pronounced in birds when using the drug at a dose of 200 and 400 g/t feed.
The lowest concentration of potassium was observed in laying hens of the control group on the 30th day of the experiment. Consequently, the use of activated charcoal feed additive does not lead to the removal of potassium from the body of laying hens, and 30 days stabilizes potassium metabolism.
Alcoholic beverage industry
Activatedacoal BAU-LV (Birch activated charcoal for “liqueur”) – a unique sorbent obtained by pyrolysis of birch wood. This process takes place in special furnaces and retorts at high temperatures without air access. The material has a developed porosity and a significant absorbing surface, so it is used to clean liquids from various impurities.
BAU-LV allows to reduce the proportion of fusel oils, aldehydes and esters in the product and improve its flavor characteristics. The material has pores of a strictly defined size, thereby delaying molecules of harmful impurities only.
BAU-LV is used for purification of vodka, wines, moonshine and other alcoholic beverages. In the manufacture of moonshine products sorbent eliminates turbidity and even increase their shelf life.
Charcoal is used in the food industry. Thus, under the code E153 on food packages, coal is registered as a food dye.
Initially, bone flour was used to purify sugar syrup from coloring substances during sugar production. However, this sugar should not be used in fasting, as having an animal origin. Sugar producers began to produce “lean sugar”, which is either not cleaned and had the form of colored sweets, or cleaned through charcoal.
Filters containing activated charcoal are used in many modern models of devices for drinking water purification.