Faculty Environmental and Chemical Engineering
Speciality: the "Environment metallurgy"
Introduction
1 Use of a limestone and lime in the Iron and Steel
1.1 Use of limestone in blast furnaces and sintering
2 Lime Production
2.2 Units for the production of lime
3 Use of lime in metalurgy
4 Characteristics of waste and methods of recovery
4.1 Generalization of the environmental situation at the JSC "Dokuchaevsky flux-
dolomite combine
4.2 Technological measures to protect air quality
4.4 Calculation of the balance of moisture with the process stream
5 Protection of the environment, working conditions and housing
Conclusion
List of reference
Relevance of the topic. Donbass is one of the major industrial regions of Ukraine and, consequently, one of the largest polluter of the environment.
A special issue of environmental safety in the production of ferrous metals mining and preparation is raw materials. One of the important components of the charge sintering, blast furnace, steel production are the main fluxes – limestone product and its burning - lime produced as steel, and on flyusodobuvayuchyh enterprises.
Extraction and preparation of these materials to the steel manufactured significantly affect the environment. In this special issue represent a violation of the earth's surface grooves career, dumps waste enrichment and purification products.
Wastes having as part of lime, are not fully used in related industries, and is often out to the dumps.
Therefore, solution preparation and implementation of techniques of preparation and utilization of specified wastes in sinter production is relevant and will not only improve the environmental situation, but also save raw materials Burdening and reduce the need for their prey.
The purpose and objectives of the research. Developing measures to reduce the anthropogenic impact on the environment of processes of extraction and concentration fluxes, production and use of lime and recycling products purification.
This was raised and addressed the following research problem:
1) analysis of the main areas of research environmental issues in mining and enrichment of flux;
2) assessment of environmental impact specified processes (air emissions, discharges into water at objects, landscapes violation);
3) development of measures to reduce the negative impact of production processes of flux, lime production and waste;
4) development of technology for reclamation of disturbed lands Dokuchaevsk Flux and Dolomite Works;
5) development of technological schemes of joint training of iron and steel vapnovmisnyh waste production;
6) evaluation of economic efficiency shlamovapnyanoyi mixtures in sintering conditions for Dnepr Metallurgical Combine im.Dzerzhynskoho.
The object of research – the process of extraction fluxes, lime production and use of waste.
Subject Research – control of environmental safety and rational nature management using waste industry.
Research Methods – Analytical analysis of the literature on the issue of environmental impact of processes of production fluxes, production and use of lime and waste. In laboratory conditions, the department RTP DonNTU studies by burning lime from limestone Dokuchaevski Flux and Dolomite Combine. Performed as research to determine the reaction ability pyliv and waste this plant equipped for the department.
Scientific novelty of the results is as follows: measures designed to reduce the negative impact Dokuchaevski Flux and Dolomite Works on the environment. The technology, compiled program and calculations required for the amount of waste lime sludge dewatering converter. Calculations savings of primary energy resources using a mixture of sintering charge.
In metallurgy limestone widely used as raw, and for lime production. Limestone called sedimentary carbonate rock that consists mainly of the mineral calcite (CaCO3).
In view of limestone – rock white or light gray, often with yellow or brown tint, very hard and dense. In the presence of mineral and organic impurities limestone acquire dark gray, black, brown, brown, green color.
In most cases most zustrichayemymy impurities in limestones are: dolomite, siderite, rodohrozyt, opal, chalcedony, quartz, clay minerals such as, oxide and hydroxide of iron and manganese, pyrite, marcasite, glauconite and other phosphates, gypsum, organic matter, vulkanohennыy material and others.
Depending on the composition of mineral impurities in the case of a large number of them, are limestones name: dolomitized, ferruginous, merhelysti, sandy, fosfatyzyrovanni, bituminous, carbonaceous, and others.
Depending on the requirements of industry carbonate raw material is divided into: limestones, dolomitized limestones and dolomites.
In limestones are rocks consisting mainly of calcite, MgO content of less than 5%.
By dolomitized limestone – limestone containing MgO from 5 to 17%.
In dolomite – carbonate rocks containing MgO more than 17%.
1.1 The use of limestone in blast furnaces and sintering at
In blast furnaces limestone used as flyusuyuchoyi supplements. Flux in the blast swimmers need to lower the melting temperature of the charge for oshlakuvannya waste charge and coke ash for sulfur binding and transfer it into slag.
For blast furnaces used limestone fraction 25-60 mm. Finished products are supplied to the limestone ore yard blast in the bins and then loaded into the blast furnace by calculating the charge. At the bottom of the mine blast furnace at temperatures of 900-1000 ° C produced lime, which reacts with gangue charge. The process of dissociation of limestone zatrachuyetsya expensive metallurgical coke.
Flux in the blast furnace may be filed with or agglomeration of pellets. These materials with high content of lime called fluxing.
In the metropolitan area using limestone fraction 0-3 mm.
This limestone fraction less than 10 mm, which comes flyusodobuvnymy enterprises in sinter plant, crushed by hammer crusher. Crushers aspiration equipment installations for ulavlennya fugitive emissions.
Lime is a product of burning limestone or chalk at 900 .. 1200 ° C. In the process of firing is the reaction of thermal dissociation of heat flow by the equation:
1 kg of limestone (CaCO3) 1780 kJ of heat (0.0607 kg umov.palyva) = 560 g of lime (SaO) 224 liters of CO2.
The theoretical heat consumption for 1 kg of lime is 3178.6 kJ. In industrial units through the inevitable loss of heat flow is significantly higher (from 3,500 to 10,000 kJ / kg, or from 120 to 340 kg conditions. Fuel for 1 ton of lime), depending on thermal unit perfection. Residual CO2 in the finished plaster 1-st class should not exceed 5%.
Figure 2.1 - Scheme manufacture of lime
By-product of burning limestone in metallurgy is carbon dioxide. Therefore, in some cases produce Lime kilns using solid fuels (coke, anthracite, thin coal) are lime and carbon dioxide.
Lime – a generic term that usually means svizhoobpalene (quicklime) lime (CaO). Depending on the chemical composition of lime may be the following:
a) calcium, or just «lime» (the main component of CaO, MgO mass part no more than 5%), calcium lime poluchene with chalk, called the Cretaceous;
b) dolomitized (MgO 5 to 20%);
c) dolomitic (MgO from 20 to 40%);
d) hydraulic (containing more than 5% silica, alumina, iron oxides chemically related to CaO).
In the plaster of the 1st grade (other than hydraulic) the amount of impurities should not exceed 3%.
In addition svizhoobpalenoho lime is used in industry as slaked lime, obtained by vzayeyodiyi calcium lime with water in the reaction CaO + H2O = Ca (OH)2
+ 1140.5 kJ / kg initial lime.
Depending on the amount of added water are distinguished:
a) lime hydrate – fine dry powder of Ca (OH)2 with little or no free water;
b) Lime paste (30 - 40% free water);
c) Lime milk (about 80% water).
Quality requirements of metallurgical lime determined by a number of specifications and standards: OST 14-16-165-85 «lime for the steel and ferroalloy industry» , «OST 14-35-78 Lime for agglomeration and others» .
Lime with Lime kilns comes in the form of lumps of various sizes, from powder (fluidized bed furnace) to 200 mm (large shaft kiln). Svizhoobpalene lime is called quicklime. Quicklime calcium lime different white, and measure clothes depends on the content of impurities: the less it is, the «whiter» lime. Other species have different shades. Dolomitic lime and hydraulic with gray.
Lime has a crystalline structure, pure CaO crystallizes in the cubic system with lattice parameter of 4.797 A. Depending on the temperature and duration of firing distinguish lime tverdoobpalene, serednoobpalene and m'yakoobpalene. The last (most common) has the following differences compared to tverdoobpalenym:
a) smaller grain size (1 .. 5 microns to 20 .. 50 microns);
b) more developed internal surface area (5 .. 8 m2 / g against 0.5 .. 1.0 m2 / g);
c) at higher total porosity (35 .. 48%) smaller pore (1000 .. 5000 A to more than 10000 A);
d) a lower specific density (1.3 g/cm3 against 1.6 .. more than 2 g/cm3);
e) less time fighting with water (0.5 .. 3 min to more than 10 min).
Apparent bulk weight svizhoobpalenoho lime 1st grade ranges 800 .. 1100 kg/m3 (lower value refers to the Cretaceous lime).
The hardness of lime depends on the properties of raw materials and firing conditions: for it is m'yakoobpalenoho 2 .. 3 to tverdoobpalenoho – 3 .. 4 on the Mohs scale.
Under normal conditions (20°C) heat capacity C = lime 765.806 J / kg. With increasing temperature heat capacity increases.
Thermal conductivity m'yahkoobpalenoho calcium lime is normally: normal – 1.3 W / m.hrad, Cretaceous – 0.9 W / m.hrad. With increasing temperature it decreases.
2.3 Units for the production of lime
The industry uses various types of lime Lime aggregates. Unit type is selected depending on several factors:
- Type of carbonaceous material (limestone vysokokaltsiyevi, dolomitized, merhelysti et al.)
- Type of fuel (solid, gaseous, liquid);
- Quality requirements for lime (a measure of firing, the content of impurities, reactivity);
- The required performance.
- Additive in ahloshyhtu in fragmented condition (less than 3 mm) to increase the productivity of sintering machines (by increasing the gas permeability of the layer and its height);
- Ensuring a given basicity sinter;
- Drying of wet iron concentrates and metallurgical production wastes (sludge, scale) in order to prepare them for use in ahloshyhti.
- Construction industry,
- Agriculture,
- Sewage treatment,
- Utilization directly to steel mills.
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The most common and traditional unit for the production of lime is a shaft furnace. Depending on the direction of traffic flow obpalyuvanoho material and furnace gas (coolant) shaft furnaces are divided into: protytechiyni, direct-flow-protytechiyni, with transverse current.
Lime is used in many fields of metallurgy, chemistry, food and non-ferrous industry, construction, agriculture and forestry, soil stabilization, water purification, marine industry and others.
In the steel industry lime is used in smelting steel and iron, in agglomeration, Mills and Ferroalloy Manufacturing in production. Steel is the largest producer and consumer of lime: about 11.4 million tons in the early 90's (ie, in the former USSR), which was about 38% of its gross output. The main consumer of lime in the Steel Industry – converter steel production (4.4 million tons). In the converter process lime is used for guidance vysokoosnovnoho slag SaO/SiO2 or (SaO + MgO) / SiO2> 3, which is due to refining of liquid steel (removal of sulfur, phosphorus, nonmetallic inclusions, oxygen, etc.).. In regard to the lime imposed strict requirements: high degree of firing (CaO + MgO> 92% ERW <5%), high reactivity (quenching time less than 3 min.) Size of the optimal (5 .. 40 mm) minimum sulfur content (up 0.06%). Converter lime making, mainly in rotary kilns, as the most versatile units, although in recent years, high-quality limestone, including the Converter, began to do in shaft furnaces. In many converter shops use dolomitic lime containing 35 .. 40% MgO to improve the resistance lining. Slag with saturated MgO and comes into chemical equilibrium with magnesite lining. When dolomitic lime consumption of 30 .. 35 kg / t steel, resistant lining increased from 500 .. 800 melting up to 2000 .. 3000 melting. In the electrical production of lime fulfills the same functions as in the converter. Consumption of it – 50 .. 60 kg / t steel. Lack of burning lime leads to additional costs elektroenerhyy. Open-hearth process is less demanding of the quality of lime and its lower specific consumption (10 .. 20 kg / t).
In ferroalloy production of lime is used as a flux (production of ferrochrome – up to 1500 kg / t of ferro - 250 kg / t ferovanadiyu et al.) And a charge (silicocalcium). Results in this segment of the CIS countries used about 700 tons of lime annually. In the agglomeration lime has several functions:
Specific consumption of lime in sinter plant varies widely: from 12 kg / t (JSC «Severstal») to 89 kg / t (MK «Zaporizhstal»). In many companies there is acute shortage of lime sintering. The final stage of surface treatment of certain types of steel before galvanizing is the etching of the surface. Remains of acid used in etching wash boiling lime milk. Consumption of lime hydrate up to 3 kg / t steel. In the refractory production of the widespread use was baked at high temperature (1700 .. 1900 ° C) dolomite. Dolomite used as raw materials for the manufacture of basic refractories in resin (pitch) or ceramic bonds. Dolomite brick successfully compete with magnesite in steel production: less resistance offset its low price.
Lime has a high refractoriness (melting point of CaO is 2570 ° C). However, Sao not stable in air modifications similar to periclase (MgO), and therefore it is in normal form can not serve as refractories. However, the processed lime has the properties of refractories. Steel smelted in the crucible of lime, has a low okyslennostyu and low content of nonmetallic inclusions, sulfur and phosphorus. This lining is best suited to the requirements of the vacuum processing of steel. Lime in the form of lime used in the manufacture of silica refractories for links quartzite grains. Quality requirements are very high lime: ERW index less than 2%, while fighting is not more than 10 minutes. The cost of lime 2.0% of the mass of quartzite.
Especially it should be noted the use of lime to obtain gold and silver from the tailings, formed after the primary extraction by washing gold ore, as well as low-grade ores. The technology is based on the solubility of them in a solution of cyanide of potassium kysnevovmistnomu. Depending on the type and amount of impurities in solution must periodically enter svizheobpalene lime to maintain the solution in working order. CaO concentration in solution is about 0.02%.
In South Africa annually use about 300 tons of lime to extract uranium from tailings gold industry. Lime hydrate is also used to extract cobalt, zinc and copper solutions. As a result of industrial activity at different stages of production generated different types of waste.
During the processing of limestone and dolomite in the waste processing plants in the form of limestone devided 0-10 mm and 0-10 mm coarse dolomite. In the process of firing dolomite in rotary kilns, the main type of waste is dust formed during roasting. Lime burn in furnaces of two types – revolving and shaft.
Disperse composition of dust determined in samples taken at Dokuchaevsk flux-dolomite combine with the cyclone and the gas flow after the cyclone. Fuel for the furnaces and rotating are mainly natural gas and fuel oil. Specific fuel consumption (on a conditional) is about 230-250 kg / t of burnt lime. When roasting limestone, a large amount of carbon dioxide, so the determination of the combustion products should take into account the dissociation reaction. It should be noted that dust ERW twice less than the limestone. So we can assume that the dust is made primarily from high parts furnace.
Chemical composition of dust and lime is presented in Table 4.1. Таблица 4.1 – The chemical composition of the components CaO MgO VPO Dust 74,0% 1,0% 25% Calx 97,0% 1,0% 2,0% Data on yield and composition of combustion products from stoves, traded, below: Output of products of combustion from the furnace, in tons burnt lime – 3300-3500 m. Composition of dry combustion products,% vol.: In Fig. 4.1 Present scheme gas cleaning installation machine now. 1 - car burning lime;
2 - Cyclones 15U;
3 - Battery cyclone; Figure 4.1 - Scheme of gas-cleaning oven roasted installation To improve the efficiency of gas cleaning from dust in addition to multytsyklonam 3 sets stage pre-treatment. Before each multytsyklonom Lime furnace installed two cyclone with a diameter of 3 m TL type 15U. The cleaning efficiency of gas is 88%, final concentration of dust in gases does not exceed 60-80 g / m. Purifying installations equipped with devices for temperature control and dilution in the gas path. Data on the fractional composition of the dust contained in the gases are given in Table. 4.2. Таблица 4.2 – Fractional composition of the dust contained in the gas-lime kilns Chemical composition of dust lime Lime kilns given in Table. 4.3. Table 4.3 - Chemical composition of dust 4.1 Generalization of the environmental situation in OJSC «Dokuchayevsk flux-dolomytnyy Works» In Dokuchayevsk flux-dolomite combine, as in any other enterprise flyusodobuvayuchoyi industry, there are problems related to the ecological safety of production processes. These problems are caused by the imperfection of technology used pylepodavlennya, enrichment of minerals and waste generated. Not enough attention is the introduction of measures to prevent pylinnya landings dust collectors and dust during transportation ulovlenoho. As a result - high zaporoshenist air of industrial premises enrichment plants. Reduce impact on Earth's surface possible through recycling of waste generated. Currently the problem is that no consumer in the by-product, produced from waste, and a huge amount of waste in dumps skladuyetsya, harming the environment Analysis of the situation in flux-dolomite Dokuchaevsk plant, shows that one of the causes of environmental problems in mining, dressing and roasting limestone is inadequate waste disposal technologies that are formed. In this regard, valuable waste of flux remain unclaimed and often just stored. Therefore, the main direction of improvement of the environment adjacent to the flux-dolomite Dokuchaevsk plant, is to improve production technology fluxes through the introduction of measures for disposal of waste generated in related industries. 4.2 Technological measures to reduce waste output Environmental problems are not limited stage extraction and enrichment of limestone, they arise at a later stage of processing, in flux enterprise. A particular difficulty with this – the collection and preparation for recycling vapnovmisnyh waste generated by burning limestone areas. As you know, one reason for the formation of a large amount of waste is the imperfection of technological units, that is no exception and during firing of limestone and dolomite.
Implementation of some technological measures will reduce the amount of waste.
Firing dribnofraktsionnyh vapnovmistkyh materials in furnaces CVP, rotating leads to the formation of rings in the oven, which gives firing mode, and therefore the quality of the finished product. Therefore, in order to reduce the charge content in small fractions, before submitting material in furnaces is proposed to classify. In addition, a measure that will reduce the formation of lime-limestone dust, by reducing the abrasion of material offered in Lime kiln refractory arrange thresholds. Thus, the suggested measures to improve the technology of burning fluxes will not only improve the quality of finished products, but also reduce waste. A few options for disposal of waste vapnovmistkyh:
The most efficient in terms of saving natural resources, recycle waste vapnovmisni in metallurgical industry, especially in the agglomeration of iron ores. Elimination of lime (0-12 mm) for sinter plant stack should add iron materials. This method of feeding reduces moisture concentrates, which will positively affect the sintering process parameters. Lime dust (0-3 mm) should be submitted directly to the flow of the charge before mixing. It provides even distribution of lime dust in total charge ahlomeratsyonnoy. For disposal of small fraction of lime rational purchase briketochnoho media company "KEPPBERN" (Germany), which will enable to increase the same amount hodnoho lime by lime bricks.
Use of waste size allows you to dramatically improve the efficiency of lime, to reduce by 10-20% or more of its costs, and reduce the overall need for solid fuel for agglomeration mainly by vysokosloynoho sintering charge. Currently, promising is the use of lime dust to dry up wet pasty sludge. With further use of shlamovapnyanoyi mixture in ahlovyrobnytstvi, as well as production zalizoflyusa for converter production. These options make it possible to not only dispose of lime, but more effective utilization of waste iron for steel making, and in particular sludge.
Thus, the utilization of lime dust in the metallurgical industry requires their preliminary training. Operations training dust before disposal followed by secondary dust formation. Therefore, to improve environmental safety steel industry needs to develop technology bezpylevu collection, preparation and disposal of lime waste. In the metallurgical industry, as in other industries widely used in various schemes of cleaning, preparation process and aspiration dust ulovlenoho in wet and dry gas cleaning devices. The most common in the steel industry of Ukraine is a wet gas cleaning, after which the securities are formed by the chemical composition of iron sludge, technology training are enough complicated. Full use of them prevent high humidity (30 50%) and lack the business areas of special training. Sludges generated due to the lack of simple and cost-effective technologies to prepare them for recycling, remain unclaimed and dumped in zoloshlamonakopychuvachi. Most of these sludges containing 30-70% Fe and other valuable components (calcium, magnesium, etc.) that could become an additional source of iron ore for through steel manufactured. The most common overseas scheme provides compression sludge dewatering pulp radial thickeners, filter on vacuum filters and drying in tumble dryers. However, the developed methods is a high energy and metal in the dehydration of large amounts of sludge. One way to improve training for sludge disposal is the use of synergies, is still provisional application of the chemical phenomena of dehydration and samotverdinnya the processing of pulp sludge znevodnyuyuchymy active components from a number of waste related industries. The simplest way is the chemical dehydration, which involves the use of calcium-and mahniyvmisnyh materials. In world practice, this method has found application and is in process of preparation edynnыy sludge disposal. This scheme is implemented and the steel plant them. Dzerzhinsky. This mix pasty sludge occurs with dry lime waste, thereby eliminate sludge drying in tumble dryers.
Properties samotverdinnya sludge in their treatment znevodnyuyuchymy materials based on waste products can be applied also for disposal of hazardous sludge waste, such as abandoned mines. This will eliminate ingress of polluted water in ponds. It is no longer the need for additional construction and maintenance zoloshlamonakopychuvachey without danger breakthroughs dams and flooding the surrounding arable land. Zoloshlamovi waste, dehydrated by the proposed technology can be used for landscape work, and the industry of various building materials. 4.4 Calculation of balance climb with the technological flow of dust and mud If the density of pure water ρv = 1 g/cm3, the density of the slurry containing the solid phase density ρt can be found by the formula: Table 4.4 – The density of sludge depending on the content in the solid phase(ρт = 4 g/cm3) Z, g/l Р,% 5 0,5 1,0038 99,50 10 1,0 1,0075 99,00 15 1,5 1,0113 98,50 50 4,8 1,0375 95,20 100 9,3 1,0750 90,70 150 13,5 1,1125 86,50 200 17,4 1,1500 82,60 300 24,5 1,2250 75,50 400 30,8 1,3000 69,20 500 36,4 1,3750 63,60 700 45,9 1,5250 54,10 800 50,0 1,6000 50,00 The balance of the materials making full use of the process stream of dust and sludge are shown in Table 4.5,4.6, 4.7. Table4.5 – The balance of moisture in the Z=300 g/l Table4.6 – The balance of moisture in the Z=400 g/l Table4.7 – The balance of moisture in the Z=500 g/l Figure 4.3 - Dependence of the content in the sludge solids from the slurry density Lime and lime products is an effective reagent in protecting and restoring the environment. In the U.S., for example, spent 1.25 million tons of ground limestone to capture sulfur in the flow of gas power plants that use solid fuel (coal, containing up to 2.5% sulfur), the waste. Using lime in exhaust gases, extracted with 99% sulfur. Used as ground limestone, but the results thus less effective and less stable. Great work on gas desulphurization of industrial units, the waste, conducted in Germany. Ulovlena sulfur, depending on the conditions, forms of lime and water vapor napivhidrat sodium or calcium
gypsum, which are, in turn, valuable raw material for chemical industry. Lime is used to clean polluted water and sewage and water bodies, rivers and coastal waters of the seas. When treatment with lime water occur following processes: a) removal of carbonate hardness of the water that prevents scale at its boiling: b) neutralization of acid water (pH increase) by binding to excess carbon dioxide; c) removal of cations, forming ions from sparingly soluble hydroxide precipitation, purification of polluted waters using lime milk; d) Removal of anions and organic compounds that form a cation Ca + hard insoluble residue (eg, phosphates, fluorides, etc.). In Sweden we are working at national level by liming rivers, lakes and artesian wells ground limestone and lime sludge. Designed special vessels for this purpose. In two of Denmark developed technologies remove phosphorus, suspended solids and organic matter from wastewater using calcium hydroxide and ferrous sulphate (or seawater). Many countries have widespread work to strengthen (stabilize) soils with lime and limestone slurry. These developments are in areas of mountain developments, landslides, hydraulic. A mixture of lime – soil exhibits such properties as strength, ductility, resistance to leaching, samovostanovlyuyuchi properties in shrinkage of the soil. The mixture allows to strengthen the steep slopes, such as ravines. A mixture of mud rocks with dolomitic dust used to zabutuvannya mine workings.
Is technology inhibition explosive coal dust in mines. For this purpose, the atmosphere of mines injected lime dust, which osadzhuyuchys to coal dust, making it explosive. Lime is used in fire engineering. The dry powder to extinguish the fires, which consists of a mixture of spent sulphide liquor and lime hydrate, in contact with air gives generous foam. One component of this mixture (liquor) are waste products.
Aqueous solutions and suspensions of lime hydrate due to the strong basic reaction used as dezynfektuyuchoho and cleaner. For this purpose, lime milk abundantly treated livestock and basements.In pond farming lime use for destruction of aquatic parasites: fish leeches, karpoedov and pathogens rotting gills. As a result of the above studies found that when mixed with lime slurry wet waste to determine the cost of lime to consider heating the mixture and parovydilennya. Measure lime hydration should thus determine in each case both experimentally and calculations. On the balance of moisture for 1 ton of wet dust to an average of 130 kg of sludge, and considering the properties of lime for dewatering sludge to 1000 kg 6958,76 kg dust. Using this method will eliminate dehydration heat drying operation, which greatly simplifies the preparation flowsheet of sludge to disposal. This technology does not require large investments, fits well into the existing sysytemu collection and evaporation and sludge thickeners provide a small building and equipment for mixing it with waste.
O2 ................................................. 5.6
N2 ................................................. 78.1
CO2 ................................................ 17.2
CO .................................................. 0.1
4 - fan;
5 - stack;
6 - lock feeders W-100
The content of the solid phase in weight percentage is calculated by the formula:
