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Innovative Technology For Municipal Waste Processing.
1. The analysis of existing methods of processing waste
1.1. Municipal solid waste. A retrospective show and prospect
1.2. Dumps and reception of biogas
1.4. Biological processing
1.5. Thermal methods of processing
1.6. Processing of oil containing waste. Complex utilization of waste
2. Advantages of offered technology
For the first time in world practice is proposed creation of the plant on the basis of new highly effective, fuel - producing and environmentally clean technology for processing of the waste, including solid municipal waste or like refuse and also of mentioned refuse together with oil-industry wastes (oil sludge, acid tars, etc.), soil polluted by pesticides and oil products, waste products of electronics, used tires, all kinds of plastics, sewage sludge of the city waste water treatment plant , the polluted ground sediment of reservoirs, biologically polluted waste of hospitals, contents of cattle mortuary, dumps, etc.
Now technology is patented, the Technologic Schedule For Design Of Manufacture For Thermochemical Municipal Waste Processing, including calculation of material and thermal balances of the plant, the data of researches and calculations of all stages of technological process and a stage of waste heat recovery, the technological circuit of manufacture, the specification of the equipment, specific material and power expenses, the control and management of the technological operating mode, definition of manufactures category and of factory premises characteristics are developed, kinds, characteristics and amount of products of the manufacture received at processing of waste products and the recommendation of their use are determined. The comparative ecological characteristic of modern incinerate plants and the developed technology is shown.
For construction in different regions, and also for reconstruction existing incinerate plants for work on offered technology it is necessary to execute the individual feasibility report.
1. The analysis of existing methods for refuse processing.
1.1. Municipal solid waste. A retrospective show and prospect.
A problem of pollution of cities by its waste products and its solving appeared as extremely complex scientific, technical, and economic problem. Special specificity here is shown in a possible concentration in these waste products practically all variety of substances and the materials meeting in the nature and artificially created by the humans, and also in continuous growth of their amount (1, 2, 3, 4).
According to data of United States Environmental Protection Agency (U.S. EPA) the total annual producing of municipal waste products in the USA for the period from 1960 till 2005 has grown from 88.1 million tons up to 245.7 million tons, i.e. more than in 2.7 times (Table 1). Such steady growth of formation of waste creates the big complexities, is especial to municipalities of the big cities. The analysis of the data presented by U.S. EPA (5, 6) shows, that in 2005 in the USA processing of waste products was carried out by ground disposal on dumps (54.3 % of the general national volume of refuse), recycling (23.8 %), biological processing - composting (8.4 %) and burning (13.6 %). Each of the specified ways has the advantages and lacks. The general lack for all above specified methods is contamination of environment by toxic substances, impossibility to provide a recoupment of ecological actions and non-polluting processing or destruction of many materials and
substances, for example, plastic, packing materials, waste products of electronics, etc. The low level of recycling of such materials as plastic (5,7 %), rubber and leather (14,3 %), the textiles (15,3 %), a paper and a cardboard (50 %), a tree (9,4 %), food waste products (2,4 %) causes economic feasibility of processing of their not utilized rests on pyrolysis installations with reception of non-polluting fuel and other commodity products.
1.2. Dumps and reception of biogas.
Now the most part of solid household waste products of the majority of large cities is taken out to the dumps located for tens of miles, and, the areas for these purposes are practically exhausted, that in addition results in formation of many hundreds spontaneous dumps (7). Thus it is necessary to take into account, that dumps are a serious source of ground pollution, subsoil waters and atmosphere by toxic chemicals, high toxic heavy metals, landfill gases, and at ignition of refuse - dioxins, furanes and biphenyls, and, maximum permissible concentration of dangerous substances are exceeded in 1000 and more times (8, 9). Application of compactors for refuse compaction allows to stack more densely it, that prolongs dumps life, however, at the same time raises specific loading on ground and, accordingly, results in the even greater environmental contamination (10, 11).
Distant transportation of solid waste by lorries and heavy trailers result in additional worsening of the ecological condition peculiar to vehicles. Besides dumps assume constantly increasing expenses of corresponding institutions as do not provide any recoupment of ecological actions (10).
It is possible to assume, however, that in immediate prospects the role of garbage dumps appreciably will not decrease. In this connection such technological approach to neutralization of refuse as sanitary soil filling, providing reception of landfill gas, will be enough actual. With this purpose household refuse covers by the soil blanket according to the certain technology by layer of puddle of ground 0.6 - 0.8m thickness. Landfill gas dumps are supplied with ventilating pipes, gas blowers and capacities for landfill gas gathering. However it is possible to use of landfill gas only in 5-10 years after creation of a dump, the output of it is not constant, and profitability is shown only at volumes of refuse more than 1 million tons. During the subsequent burning of landfill gas the most part of its toxic components are destructing with the exception of heavy metals, which are reset then into an environment. It is necessary to note also, that the earth and superficial waters penetrating through soil filling, grasp dissolved and suspended solid substances and products of biological decomposition, than in addition pollute an environment (1, 11). Besides landfills are responsible for an estimated 36% of all methane (greenhouse gas) emissions in the USA (12).
Movement for an interdiction of dumps creation near to settlements now considerably increased and has made necessary search of other ways of processing and destruction of solid waste products .
Economically the most attractive could be sorting of the mixed refuse, including on the automated sorting complexes, with the subsequent returning a significant part of components into manufacture. However it is extremely toilful, epidemically and toxically dangerous process, allowing to sort no more than 30 % of refuse as its big part is impossible to separate (9, 13). At initial sorting of refuse in places of its formation about 80% of useful secondary raw materials (9) are possible to take out. It is necessary to note, however, that the level of recycling considerably depends on the general culture and discipline of the population and also that plastic packing materials are difficult and expansive to recycle. As various resines cannot be mixed, plastic materials should be not only sorted, but also processed separately. Such labor-intensive process essentially raises cost of processing. Thus many companies cannot use them because of poor quality and bad structure in comparison with the products received from normal raw material. Therefore these materials can find only limited application for packing, for example, food and pharmaceutical products, i.e. for the products having the greatest market concerning packing. Thus, recycling plenteous of plastic is a unreal purpose. Experience of Germany has shown that recycling is economically expedient only for such materials as steel, aluminum, glass, depending on local conditions, probably, a paper and is completely unacceptable for plastic, packing materials, newspapers, waste products of electronics, etc. (14). Now Switzerland and Japan have achieved accordingly 23% and 20% of waste products recycling (15), and in the USA now 23.8 % of waste products are recycling (5). It means, that at least 65 - 70 % of solid waste should be processed by a different way.
1.4. Biological processing.
It was supposed, that the major direction of recycling solid waste will be its processing into organic fertilizer - compost (1, 2). Among known methods of processing (with a purge of air in stacks, in mesh chambers, on louver shelves, in vertical towers) the most effective and hygienic for today is the method of bioprocessing in rotating cylindrical drums. Process occurs in full isolation from the humans. Difficulty of realization of this method is in necessity of complex sorting and preliminary solid waste processing that entails necessity of construction of an additional factory for sorting refuse. Besides received compost is sated with heavy metals and other harmful components of refuse (16). Actually it is suitable only for recultivation and overlapping of dumps. The majority of these factories is unprofitable (17). The same lacks are inherent also in a way of processing of organic waste products by Californian red worms allocating valuable organic fertilizer - humus. Besides this method demands application of manual skills and for large industrial scales is poorly suitable (18, 19).
1.5. Thermal methods of processing.
Now in world practice has realized more than ten technologies of processing solid household and industrial wastes. The most widespread among them are thermal ways - burning, pyrolysis and gasification.
Burning cannot be considered as economically justified or saving resources method as many organic substances which could be used, are burnt with additional consumption of energy (20). Besides existing and offered plants for refuse insineration have a lot of lacks, the main among them is forming secondary extremely toxic waste products (polychlorinated dibenzodioxins, -furanes, and -biphenyls), allocated together with heavy metals in an environment with chimney gases, sewage and slag (21).
It is necessary to note, that chlororganic waste products frequently named "dioxins", pertain to supertoxic group, the steadiest and extremely dangerous as destroying hormonal system of the human, that results in an immunodeficiency, is especial to growth of female illnesses, children"s death rate and physical inability, decrease of birth rate (20, 22). On May, 25 2002 in Stockholm the Global International Convention on prohibition of persistent organic pollutants has been accepted. The group of 12 listed highly dangerous substances includes mentioned earlier dioxins, furans and biphenyls (60).
Dioxin formation components of waste products are such materials as polyvinylchloride, linoleum, plastics, packing cardboard, newspapers, etc. (23). Toxic metals are thrown out in the form of salts or oxides, that is in a steady kind, and can be in an environment uncertain quantity of years, gradually collecting and with a dust getting into human body that results in defeat of a liver and a gastroenteric path, autoimmune to diseases of joints, diseases of nervous system and psychoneurological frustrations, genetic changes at descendants, to increase of sensitivity to ionizing radiation, osteoporosis of tubular bones (24, 25).
Concentration of heavy metals oxides in slag and ashes in 2-3 times (and sometimes more) is higher, than in burning waste products. Therefore, though the method of burning allows to reduce considerably volume of waste products, thus even more dangerous to an environment ash and slag demanding special recycling measures or a burial place are formed (20).
Now for toxic slag processing the technology of ecoconcreting is used: mixture of slags after their neutralization with cement, lime or silicon dioxide with the subsequent hardening of mixture. At correct mixing ratio waste products to the bonding agent occurs an "incapsulation" toxic substances (including heavy metals and dioxins) in the cement stone, which is not passing, in authors opinion, ecotoxicants into an environment. However, such technology demands preliminary neutralization of waste products for what a plenty of chemical reagents is necessary. A number of the substances making waste products, for example, sulphur-containing, can cause degradation of a cement stone that results in penetration contaminators into an environment (26). Besides toxic metals in the certain conditions can be washed away from blocks by rains, for example, at change of acidity of rain water "on weather conditions" (20). Now the advanced method of ecoconcreting - integrated mineral-matrix technology (Iлл-technology) is developed, which should provide ecological safety of a received material due to chemical bonding contaminators down to their inclusion in a crystal lattice of cementing new formation (for example, heavy metals) or blocking contaminators by colloidal-disperse and sol-gel phases in mass of a forming material. However, as authors specify in same publication, it is possible only "at rationally picked up components of system when potential chemical properties of components of system and their mechanical characteristics are summarized" (26). Commercially such condition cannot be executed, as structure of municipal refuse and, accordingly, slag is not constant.
Thus, even the advanced technologies do not provide manufacture of non-polluting, suitable slag for the further use, municipal refuse received after burning. Thus it is necessary to note, that cost of a burial place of dangerous waste products (ashes and slag) 10 times higher, than a burial place of refuse (20).
Other serious lack of incinerators is their low profitability. So, in New Jersey (USA) in 1997 seven incinerators had total debit in 1.6 billion dollars(27). It speaks in the low coefficient of useful consumption of heat energy which even on the best plants for municipal refuse incineration does not exceed 65 % (28) and a significant amount of used an additional liquid fuel reaching 70 gallons per ton of burning waste (29).
To the modernized ways of burning of solid waste it is possible to attribute replacement of air submitted to a place of burning, by oxygen (30). It allows to speed up process, to lower emissions of nitrogen oxides, however emission of the most dangerous components - dioxins, furanes, biphenyls, heavy metals - remains constant. Besides the similar technology demands additional significant expenses for generation of oxygen.
As burning waste products produces heat, the desire to use it was natural. So movement "Waste-to-Energy" has appeared (31, 32, 33). However, burning of solid waste with the purpose of heat reception to manufacture the electric power results in the even greater environmental contamination. It speaks that the electric power consumption is not constant and has daily and seasonal peaks, that, accordingly, results in fluctuations of loading of combustion chambers of garbage incineration boilers and, as a result, to incompletely burn of waste products and to the even greater emission of harmful substances with chimney gases, slag, ash and sewage. For only technical reasons cost of the electric power made at municipal refuse incineration plants cannot compete to cost of the electric power of heat power stations. The price of one kilowatt at heat power stations is 1 - 3 cents, and at refuse incineration plants - 11 cents. However, on laws in force for stabilization of the market to consumers it is obliged to sell energy for 2 cents per 1 kilowatt, that gives enormous losses for refuse incineration plants, and in a combination to necessity of a burial place for slag and ash makes these plants absolutely unprofitable and financial forecasts for their development are extremely adverse. (34)
Now authorities of New York plan to use the gas received at burning of waste products of a megacity, for manufacture of electricity at eight recycling refuse factories. In New York has already installed eight 200-kilowatt fuel batteries at four plants of Brooklyn. Mayor of city Michael Blumberg has explained, that "fuel elements will transform garbage gas in electric and thermal energy and thus do not poison air of nearby neighborhood" (35). Really, fuel elements have some advantages. The main thing - these elements are much more efficient in comparison with any other ways of electric energy generation. Efficiency of already existing elements is 50%, theoretically it can be more than 85%.
The electric power in batteries is developed directly due to chemical reactions and in this case it is not required the intermediate parts used at power stations (boiler units, turbines) which reduce efficiency of energy reception. Non-polluting fuel elements develop the electric power due to electrochemical reaction between hydrogen and atmospheric oxygen, and, as a by-product water (36) is formed only. However, using methanol the process ceases to be rather non-polluting as methanol at decomposition forms not only hydrogen but also poisonous carbon monoxide (CO). It is necessary for utilizing, and, the simplest way to achieve it is carbon monoxide (CO) up to carbon dioxide (CO 2) which then will be thrown out in an atmosphere. Thus, finally a problem of emission reduction of greenhouse gases in an atmosphere in such a way to solve it is not possible (37). At use in fuel elements of the gas received as a result of refuse burning, the problem of environmental contamination remains at all not solved as the most dangerous toxic substances - dioxins, furanes, biphenyls, heavy metals, etc. cannot be detained in fuel batteries. Besides the slags received after refuse burning also are dangerous and require a burial place.
The level of burning of household waste products in some countries is various. So, from total amounts of household refuse the share of burning fluctuate in such countries, as Austria, Italy, France, Germany from 20 % to 40 %; Belgium, Sweden - 48-50 %, Japan - 70 %; Denmark, Switzerland - 80 %; England and the USA - 10 %; Russia - 2 % (30).
Now many scientists consider, that incinerators cannot be the non-polluting plants at all. Among supporters of this point of view are Paul Connett - the professor of chemistry from university in Canton (N.Y.), Michael Gendron from Ontario which has entitled article on September, 8, 1999: " The Full Health Implications of Waste Incineration are Unknown ", Neil J. Carton - former Clean Air Program Director, Austin (Texas), toxicologist from state Maine Robert Frakes, etc. (38). The head of the organization of independent experts of Russia Doctor of Chemistry S.Yufit has convincingly shown not only danger of incinerate factories, but also their inefficiency, ecology destruction and absolute economic unacceptability for any local budget (20).
Recently many companies pass from simple burning waste to the two-level process including a stage of pyrolysis (decomposition of organic substances without access of oxygen at rather low temperatures 450 - 800°C). Such process appears energetically more favorable, than simple burning. As a result of pyrolysis receive gas and solid rest of pyrolysis. Then those and other products at once, without any additional processing, direct to the furnace to burn. The part of gases of pyrolysis after condensation can be deduced from system and is used as liquid fuel by other consumers (39, 40, 41). There are the same lacks, as at direct waste products burning. In the cases when gas of pyrolysis is refining from acid gases such as hydrogen chloride (HCL), economically process becomes expensive enough because of application of the expensive equipment and using of expensive caustic or calcinated soda and environmental contamination by heavy metals is not eliminated.
Alternative to process of pyrolysis is the process of gasification which goes similarly, but at temperature 800 - 1300°C and at presence of a small amount of air. In this case received gas represents a mix of low-molecular hydrocarbons which then are burning in furnace (39, 42). Unfortunately, such process does not improve an ecological situation, whereas presence of air and contained in refuse chlorine organic substances in combination to high temperature results in intensive formation of dioxins, furanes, biphenyls, and salts of heavy metals, as well as in other technologies, from process are not deduced and pollute an environment. Anyway in materials of the U.S. EPA (Table 2) such comparative characteristics are presented (43):
The name of pollutant
kg/t waste products. Gasification plant,
kg/t waste products.
Dioxins and furanes
Dioxide of sulfur
Oxide carbon 0,7 x 10 -7
3 x 10 -3
14 x 10 -4
0,21 0,6 x 10 -6
3 x 10 -3
13 x 10 -4
The most complete destruction of the products contained in refuse, is carried out during high-temperature pyrolysis or gasification at temperature 1650-1930°C in melted metal with mineral additives (44), or at temperature up to 1700°C in melt of salts or alkalis in a mix with additives and at the presence of catalysts (45). The specified ways provide refuse processing practically of any structure as at such temperature are completely destroying all dioxins, furanes and biphenyls. As a result it turns into synthesis gas - a mix of hydrogen, methane, carbonic oxide, carbon dioxide, water steam, nitrogen oxides and sulfur, the solid rest - coke, pieces of inorganic materials, lime, cement, glass and slag which are proposed to be removed from a reactor in sealed bunkers and forms without the indication of their further use and wasted melts of salts and metal which regeneration is extremely complex and power-consuming process demanding besides the significant consumption of various reagents. Synthesis gas after enough complex clearing of impurity can be used as fuel. It is necessary to note also, that the specified processes do not provide allocation of heavy metals and their salts from the firm rest of pyrolysis, therefore the further utilization of slag for manufacture of building materials and designs is impossible, special measures of their recycling or a burial place are necessary.
Recently the technology of processing of waste products on a basis of low temperature plasmas (2000 - 10000°C) began to develop. As the rest of process there are receiving heavy metals which can be used in metallurgy (46). One of lacks of this method is its high operational cost. So, company Solution NTT working together with Institute of Electrophysical Problems (Moscow), specifies, that it makes 100 dollars for ton of waste products (47). Other lack which practically excludes a real opportunity to apply this method in large industrial scales, that fact is, that the material of the reaction chamber at such high temperature quickly fails and it is necessary to stop it very frequently to repair.
1.6. Processing of oil containing waste. Complex utilization of waste.
The emergency situation has developed all over the world with utilization of the oil containing waste, liquidation of oil sludge and acid tars accumulators, clearing of the ground polluted with mineral oil.
The liquid waste products containing more than 14 % of mineral oil are mainly burnt. Most perspective as fuel is water-mazut emulsion. At the contents of mineral oil in waste products less than 14 % are used microbiological methods of clearing (48). Till now, however, the comprehensible solution of the challenge - clearing of the ground repeatedly polluted with mineral oil (for example, a ground of gas stations, seaports, railway depots, tank farms, etc.), recycling of acid tars (waste products of sulfuric purification of some mineral oil, for example, the lubricant oils, containing 15 - 70% of the sulfuric acid dissolved in water), utilization of ground sediments of oil tanks, ponds - sediment bowls, earthen sludge barns representing a solid phase, containing paraffin, asphalt-resinous substances, sulfur, sand, clay and other mechanical impurity, and also heavy metals - lead, cadmium, zinc, etc is not found.. (49, 50). It is proposed to process such waste products in units of thermal neutralization where as a result of pyrolysis receive, as authors assert, dry neutralized carbon containing material - raw material for manufacture of building materials and asphalt concrete mixes, and also the condensate and the gas used as fuel in these units (51). It is necessary to note, that such solution of a problem is not satisfactory as the solid rests of pyrolysis contain heavy metals and, hence, are not suitable for industrial use and a burial place demands. Also for that extraction of oil from ground deposits is inexpedient in connection with high expenses and insignificant amount of an oil phase: at the average 5 - 8% (52). Recycling of acid tars - waste products of sulfuric clearing of some mineral oils, for example, lubricant oils - a problem of the governments of many countries. Tars are dangerous, as containing resinous substances, organics, heavy metals, sulfur, products of polymerization of nonsaturated hydrocarbons, and amount of the sulfuric acid dissolved in water, reaches 70 %. The way of storage of tars in open for this purpose foundation ditches which turn then in oil tar lakes is not less dangerous to an environment, the layer of water in which actually makes only 0.3 - 0.4 m, and then is 7 - 8 m depth is tar like substance. The majority of recycling ways are reduced to regeneration from acid tars the sulfuric acid and to burn the neutralized rests or to neutralization by limestone with the subsequent burning at thermal power stations. As a result into an atmosphere are dumped highly toxic substances (53) that are not acceptable at all at the present time.
The most rational way of the solution of oil sludge recycling problem is observed at joint process of pyrolysis with solid municipal waste products (54). Correctness of economic feasibility of such technology is confirmed with introduction some installations, providing joint recycling oil contenting, rubber-fabric, textile waste products, oiled rags, sawdust, waste products paint and varnish materials, a polymeric film and others (55). However, the questions connected to protection of an environment from pollution by heavy metals, dioxins, furanes and biphenyls also are not solved.
Now in world practice some technologies of joint thermal processing of solid municipal waste and sludge deposits of the sewage formed at city sewage purification plants. Thus their joint burning in furnaces of various designs with preliminary drying deposits and obligatory returning of chimney gases after drying for deodorization in a furnace is provided (56, 57, 58, 59).
In connection with the elevated content of heavy metals in sludge deposits of sewage all these technologies result in producing of extremely dangerous slag and ashes which demand a burial place. Besides chlororganic compaunds contained in solid waste, leads to environmental contamination by dioxins, furanes and biphenyls - the extremely dangerous to human health and an environment.
Thus, the problem of clearing of places of mass human dwelling for the present moment has no satisfactory solution.
2. Advantages of offered technology.
Disadvantages of existing methods of municipal solid waste processing, mentioned above, completely are eliminating in offered technology which differs from above mentioned:
- the technology is based on well-known and repeatedly checked up methods in another industries. Actually the new technological chain consist of old well-known parts which, however, entirely now still is not carried out anywhere;
- allow to process effectively waste products of any humidity, including frozen together;
- does not require preliminary sorting of waste, however, depending on local conditions and economic reasons it is useful by known methods to remove objects, which recycling is expedient, for example, ferrous metals, aluminium, glass, etc. though the technology itself does not demand it;
- produces fuel which in connection with deep heat recovery in productions covers self-consumption over the odds that allows to refuse use of fuel from outside sources (except for the starting period) and provides an output of commodity fuel to the market;
- coefficient of useful consumption of thermal energy in technological processes of the plant is equal 91.1 %;
- in case of using of all received commodity fuel for manufacture of the electric power directly at the plant, for example, on diesel engine - generating installation - is completely provided self consumption of the plant, that allows to abandon use of the electric power from extraneous sources (except for the starting period) and delivery of the electric power on the market in regional electric networks is provided in addition;
- produces a variety of ecologically clean commodity by-products: dry calcium chloride, liquid carbon dioxide, concentrate of salts of the heavy metals, purified from impurities (heavy metals and sulfur) slag and slag-concrete products;
- reduces a production cycle, increase of physics √ mechanical parameters of slag-concrete products due to their thermohumid treatment;
- requires no sewage system by utilizing waste waters in the process itself, that simultaneously reduces on 93.4 % consumption of fresh technical water;
- a production waste are only smoke gases which structure fully complies with all requirements of ecological safety norms that is achieved directly during technological processes of waste processing and reception of commodity products without installation of any additional clearing equipment as offered technology:
- does not produce chlorine organic substances such as dioxins, furanes and biphenyls and, accordingly, excludes their emission into an environment;
- does not eject highly toxic heavy metals, including radioactive, into an environment;
- does not eject highly toxic carbon monoxide, organic light and unwell smelling substances into an environment;
- reduces emission of carbon dioxide (greenhouse gas) on 57 %, nitrogen oxides on 72 %, sulfur dioxide on 60.2 %, benzopyrene and smoke particles on 24.6 % in comparison with modern working garbage incineration plants and industrial boiler-houses;
- use the serial, easily accessible equipment;
- capacity of the plant can be varied in wide range of parameters, because it consist of separate autonomous technological lines (modules);
- all processes are continuous, fully-automated, not toxic and not explosive;
- independent work of the plant, for example, in the remote areas at dumps of solid household waste is possible as the technology allows to provide completely self-consumption of the plant in fuel, electric power and technical water at full absence of industrial sewage and solid waste.
Commodity products of this technology are: liquid fuel with heat value of ~8,150 kcal/kg (14,670 Btu/lb), dry calcium chloride, liquid carbon dioxide, concentrate of salts of the heavy metals, purified from impurities slag and slag concrete products.
Use of all received commodity fuel to produce the electric power directly at a plant provides self consumption of the plant and delivery of the electric power to consumers in regional electric networks. As a result of calculations it is established, that from one ton of municipal waste of average structure it is possible to expose to the market: 92 kg of liquid commodity fuel or 212.7 kWh the electric power,
32.4 kg of dry calcium chloride,
50 kg of liquid carbon dioxide,
4 kg mixes of salts of heavy metals and coke or coal (including 150g actually salts concentrate)
and 0.52 m 3 light-weight slag concrete.
Liquid fuel is used for heating buildings and in power boiler installations, liquid carbon dioxide - for carbonation of beverages and in welding practice.
Calcium chloride is applied to acceleration of concrete hardening, as deicer for roads and railway switches, against regelation of coal and ores, for preparation of refrigerants and medical products.
The slag purified from heavy metals and sulfur is used for road construction or as fill material for manufacture of slag concrete products.
Mix of heavy metals with coke or coal is raw material for the metallurgical enterprises working with complex ores where the specified mix is used as charge stock.
Expected payback of the plant construction in New York is 3 years. In calculation the economic estimation of the prevented ecological damage to an environment is not taken into account in comparison with incinerate plants and industrial boiler-houses due to exclusion of emission in an atmosphere especially dangerous (dioxins, furans, biphenyls, heavy metals, hydrogen chloride) substances, significant decrease of dangerous (carbon and sulfur dioxides, nitrogen oxides, benzpyrene and smoke particles) substances, exclusion of dump of industrial sewage and liquidation of special ranges for a burial place of toxic slag (freeing of the ground and money for the maintenance of these dumps). According to it is possible to assume, that the real time of recoupment of plant construction will be much less than expected. Full calculation of economic efficiency can be executed only after development Technical–and-economic assessment of construction of the plant pegged to certain territory. References
© Yuriy Rabiner, Ph.D
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