BRIQUETTING
COAL BRIQUETTING
The briquetting processing of the material in pieces of geometrically regular and uniform in each case form, almost the same mass – briquettes (French briquette). When Briquetting create additional raw materials of fine materials (mainly fossil fuels and ores), whose use is inefficient, or inconvenient, as well as recycled waste (culms, sludge, dust, slag, metal shavings, etc.). Feasibility Briquetting in each case, the economically justified.
Depending on the source material is Briquetting with a binder at intermediate pressures (10-50 MN/m2) and without binders at high pressures (100-200 MN/m2). For briquettes of high quality material, directed at pressing, must meet certain requirements (fractional composition, humidity, temperature, etc.).
Briquetting of fossil fuels (Dropped out of stone and similar old brown coal with a relatively strong mechanical structure, private’s weakly structured young brown coal and peat) is produced mainly for energy and public utilities in the briquette factories. Ash obtained briquettes to 20%. They are well opposing gravitational forces, withstand long storage in the open air, are not destroyed before the end of combustion. Briquetting is used as part of new methods of coking for metallurgical coke from the gas and weakly caking coal. Lean coal, anthracite, the old brown coal, semi-briquetted with binders (coal tar pitch in solid or molten liquid form, petroleum bitumen, etc.).
BINDERLESS COAL BRIQUETTING
Briquetting enhances calorific value of coal lignite fines and improves the efficiency of combustion, portability, storage and use of these types of fuel raw materials.
Depending on the properties of the feedstock briquettes made without binders (young brown coal, peat). When briquetting without binder is filled voids between the particles are compacted and deformed particles themselves, between them there are forces of molecular adhesion. Increasing pressure results in a decrease of the elastic deformation and move them in plasticity, whereby the structure of the briquette hardens. Young brown coal briquetting without binder produced for household needs.
Young brown coals (Wp to 60%) to a certain size are crushed and dried in a drum dryer until the optimal humidity. The dried coal is pressed into the roller presses, briquettes are cooled to 40-45 ° C and shipped to some warehouse customer requirements.
COKE BRIQUETTING
Coke and Coke breeze. These wastes are in the coal mines and steel mills. A promising way of recycling – briquetting in domestic and industrial fuel briquettes for high-power rotary presses (briquette size 70x70x40mm). Briquettes can be sold to the public and metallurgical plants.
The briquettes are made in a formation machine for concrete products whereby the briquettes are shaped as cubes having an edge of about 8 cm . The wet cubes are stored for 12 days, whereupon they are dried for 24 hours and at a temperature of 60° C. The pressure strength of the briquettes in cold state is measured to 2,639 kPa (26.9 kg/cm 2 ), which value is an average value of six briquettes.
For making it possible to check the heat strength of the briquettes they are subjected to a temperature of 900° C. for one hour, whereupon they were allowed to cool for 24 hours before the heat strength was measured. A value of 2,246 kPa (22.9 kg/cm 2 ) was obtained, which value is an average value for six briquettes.
Briquettes having the above identified composition have a pressure strength in cold state which is slightly less than the above mentioned recommended value of about 2,943 kPa (30 kg/cm 2 ), whereas the heat stength is substantially higher than the above mentioned recommended value of 981 kPa (10 kg/cm 2 ). In the following tables A and B an additional number of examples are given for different mixtures for the manufacture of briquettes, whereby the tables give information about composition, pressure strength, heat strength, evaluation of the strength and observations:
Claims: 1. A briquette suitable for use as an auxiliary fuel in a shaft furnace for melting of mineral in the manufacture of mineral wool comprising:
(a) 30-75% by weight, based on the dry weight of the briquettes, of particles of coke fines or coal fines or both, said fines consisting essentially of particles having a particle size of from 2 to 25 mm ;
(b) at least 7% by weight, based on the dry weight of the briquette, of a hydraulic binder;
(c) at least 15% by weight, based on the dry weight of the briquette, of a fine grain oxidic mineral component selected from the group consisting of sand, slag, stone powder, fly ash, limestone powder, dolomite powder, silicon dioxide, and waste material from mineral wool manufacturer, said fine grain oxidic mineral component having a particle size of less than 2 mm . 2. A briquette according to claim 1 wherein component (a) comprises a mixture of coal and coke particles, the amount of coal particles being 10-50% by weight of the mixture.
3. A briquette according to claim 1 wherein compound (b) comprises cement in an amount of 8-35% by weight, based on the dry weight of the briquette.
4. A briquette according to claim 1 wherein component (c) is present in an amount of up to 35% by weight, based on the dry weight of the briquette.
5. A briquette according to claim 1 wherein said minimum particle size of component (a) is 5 mm .
CHARCOAL BRIQUETTING
Industrial application of charcoal, through briquettes.
The history of charcoal and history of metallurgy are closely connected. Charcoal long years was unique fuel for metallurgy. The beginning of “Iron Age” IX… of VII centuries up to the middle of XVIII century, manufacture of charcoal was the developed industry. Our ancestors applied charcoal to melt of iron in furnaces and at the further improvement of steelmaking technology in domain. Metallurgy and forge business – one of the first industrial applications of charcoal. But after the invention in the middle of XVIII century, Abraham Derby of a way of reception of coke from coal, coke became the basic fuel for melt and thermal processing of metals, having superseded with this market charcoal. Today the situation on application of coal coke as fuel for metallurgy has cardinally changed.The global deficiency of coke explained by growth of consumption of raw material by metallurgists, put on a side of a stop of manufacture of lead, nickel, pig-iron, ferroalloys. Because of growth of cost of coked coal cost of coke for last two years has grown in sometimes.
Whether can replace presently charcoal coke and how fuel to meet modern metallurgical requirements? Charcoal on a number of parameters surpasses coal coke. The maintenance of phosphorus and sulfur that is much important for metallurgy below what at coke. Also charcoal surpasses coke under the maintenance of carbon. Application of charcoal is not accompanied by emissions in an atmosphere of hotbed or toxic gases. Coke, in turn, surpasses charcoal on such parameters, as thermal ability, bulk density.
Charcoal briquettes – the fuel uniting properties of coal coke and charcoal. The chemical compound and density in briquettes are formed is artificial, and these parameters can change depending on inquiries of the consumer. Modern opportunities allow to enter into structure of briquettes components which can adjust duration of burning, reactionary opportunities of briquettes. Also the components improving qualities of selected metals and alloys can be included in structure. The decision of a problem of increasing deficiency of lumpy ore can be the briquettes comprising powder ore or a dust of ore, received at extraction. If components of briquettes will be metallic waste of manufactures, it will be the decision of a problem of dumps and the burial grounds aggravating ecological conditions around of the metallurgical and metal cutting enterprises. Consumption of coal coke grows every day.
Fuel for metallurgy is one of set of opportunities of application of charcoal. Briquettes can beapplied as a reducer at molding bronze, a brass, the cupronickel, the zinced wire, by manufacture of crystal silicon.
Whether the forest chemical industry can cope with such volume? As it was mentioned earlier, Charcoal briquettes – a product of processing of waste of a timber industry complex. Their manufacture is connected with an opportunity of largetonnage use of inevitable waste of wood raw material at preparation and its processing at cutting woods and a tree the processing enterprises (sawdust, etc.) High rate of growth of a timber industry complex which we can observe for last years, and also absence of modern highly profitable technologies of processing of waste preconditions for formation of a rawmaterial base for the organization of manufacture Charcoal briquettes.
CARBON BLACK BRIQUETTING
BRIQUETTE MAKING OF CARBON BLACK FROM PYROLYSIS PROCESS OF SCRAP TYRE
Carbon black has higher calorific value, fixed carbon and low sulphur and ash content; it can be potentially used as high quality fuel either in briquettes. The briquette making of fine carbon (powder form) from scrap tyre pyrolysis plant is slightly more difficult than production of briquette from coal or charcoal. The oil content in the carbon powder is one of the factors. Normally oil content in the carbon powder should not be higher than 2-3%, otherwise binder will be required. In case that binder is required, the mixing of fine carbon powder and binder dispersion are the key to the success of briquette production.
The higher fixed carbon, calorific value and low sulphur and ash content of coarse fraction suggests that it can be used as high quality clean fuel briquettes.
SALT BRIQUETTING
Salt briquetting machine has features of high pressure and high briquetting efficiency. Briquetting in the form of briquette corresponding to the salt harvested from the crystallizer that has undergone by spinning, washing process, a drying process, screening and compacted into briquettes with physicochemical characteristics in accordance with its data sheet.
SODIUM CYANIDE BRIQUETTING
Sodium cyanide – an extremely toxic substance, it is very dangerous to humans and animals. Therefore, when it applies the corresponding production equipment, preventing the penetration of substances into the environment.
The production process used by enterprises, is periodic, and by using conventional techniques in the manufacturing process is obtained dusting powder, the content of the basic substance – 88%. Mostly used continuous process in which the content of the basic substance is 98%. Sodium cyanide and grunuliruyut pressed and briquetted to reduce the harmful effects of dust.
DOLAMITE - MAGNESITE POWDER BRIQUETTING
In steel production in large quantities are used dolomites as flux and refractory materials. When dolomite mining in quarries, as well as in preparation for use (transportation, annealing) a significant amount of dolomite goes to waste in the form of dust and crumbs, which cannot be used in steelmaking.
A significant amount of dolomite dust accumulates in the dust and electrostatic chambers.
In production, transportation, preparation and use of lost up to 40% of the annual consumption of dolomite.
These waste products in the form of dust and crumbs cannot be used in the production of converter steel and go to dumps as process conditions for dolomite in pieces of dimensions charge should be in the range 20 – 70 mm.
To solve the problem of waste return dolomite in the technological cycle of production need to be developed converter dry pressing technology small fraction dolomite pellets satisfying the specifications and size, density and strength, as well as equipment for the implementation of this technology.
This problem has recently become particularly relevant due to the tightening of environmental regulations and increasing fees for use of natural resources.
IRON MILE SCALE BRIQUETTING
The composition of briquetted charge includes 70-75 wt. % Of ferrous material (slag, dust, gas cleaning system and so forth.) And the solid reductant quantity required for complete reduction of the iron melt and carburization. As a reducing agent can be used a variety of carbonaceous materials, such as waste electrode production, coke breeze, fight graphite blocks.
EAF DUST (ELECTRICAL ARC FURNACE DUST) BRIQUETTING
Electric arc furnace (EAF) dust is a hazardous waste product of the steelmaking industry with a high concentration of heavy metals, especially Zn and Pb. Existing treatment processes are industrially viable only when the zinc content is sufficiently high. In this project we present an industrial-scale process to enhance EAF dust by recycling it to the same furnace in which it was generated.
The manufacturing of self-reducing briquettes composed of dust from the steelmaking improve the chemical, mechanical and thermal properties of the briquettes. These include determinations of compressive, breaking and abrasion strength, softening and melting points, and thermal behavior. The theoretical energy balance calculated from the process of loading briquettes into the EAF has yielded a positive value of briquettes, showing that extra energy is clearly supplied to the furnace.
ALUMINIUM DROSS BRIQUETTING
BRIQUETTES FROM THE WITHOUT SALT ALUMINUM DROSS
Our project can be defined as; sort out aluminium white dross and salt slag (black dross) with mechanical seperation for metallics and additionally dissolve / leach salt additions to gain salt and clean oxide and finally press clean oxide mixtures at our roll press in order to get “aluminium dross briquettes”.
This whole process serves you to get your metallics (aluminium, iron and etc.) , transform your black dross or hazardous waste into non-hazardous waste and also gives opportunity to create a new product from your waste by getting “oxide briquettes”.
Maybe you know, maybe you dont, the aluminium oxide briquettes are used for a fluidizing agent at iron&steel industry. It is being directly charged to iron&steel slag to get the desired aluminium oxide percentage, so the steel industry is eagerly asking for these kind of product worldwide for the last 5-10 years.
MANGANESE BRIQUETTING PLANT
BRIQUETTING MANGANESE PRODUCTS WITH THE INFLUENCE OF FINE FRACTIONS
Now in Russia sharp deficiency of manganese ores is felt. The modern need of the industry makes 1,3 million tons of manganese concentrates. As a result of enrichment fine products are formed. The reconnoitered stocks of manganese ores in Russia make 148 million tons which are concentrated in 13 fine deposits of the North-Ural manganese -mining basin and Western Siberia . Ores of these deposits cannot be involved in metallurgical processing without enrichment. Feature of processing of manganese ores is the formation of a significant amount of fine fractions with a high mass fraction of valuable components. When the enrichment of manganese ore fine fractions are formed in the process of ore preparation. As a result, metal manganese ore produced minor products (screenings, flue dust and cyclone). In the year produced more than 0,7 million tons of dust and the loss of manganese with them are about 7-8 thousand tons per year. Minor products formed during the enrichment of manganese ores, and cannot be involved in the processing without briquetting. Thin fractions influence briquetting. However, their impact on the efficiency of briquetting studied sufficiently. Need to define the role of fine fractions in the mechanism of formation and hardening of briquettes, the definition of optimum conditions for briquetting of products with thin size classes.
The work to investigate the role of fine fractions in the mechanism of briquetting and the development of technical solutions to improve the technology of processing of manganese products using briquetting, is actual. The aim of our work is to develop technology for the processing of manganese products in the light of fine fractions. The idea of work is to establish and ensure the optimum balance of class size in briquetting manganese products.
Our task:
– Briquetting of fine fractions of manganese ores.
The practical significance of the work is to develop technologies for the processing of manganese products using briquetting in determining the optimum briquetting manganese concentrates.