The latest methods of waste processing. Dump of great ideas: the most original ways to dispose of garbage. PCB recycling technologies
Environmental protection is one of the most urgent tasks of our time. Waste from industrial enterprises and household human activities reaches large volumes, which affects the pollution of the atmosphere, water bodies and the bowels of the earth, the level of which today in many cities exceeds the permissible sanitary standards. Environmental studies have shown that over the past decades, the destructive impact of anthropogenic factors has led to the onset of an ecological crisis.
Waste management is a complex environmental, technological and economic problem that many countries are struggling to solve at the highest level. The search for technologies and the production of equipment for the processing and disposal of waste is today a sought-after and promising area, the development of which is supported by public and private investors.
At the moment, in world practice, there are several methods for waste disposal, each of which has both positive and negative sides. The disposal method is selected depending on the quantity and quality of waste from the list below:
- The fire method is one of the most versatile and in many cases the only possible method. Such disposal can be used for liquid, solid and gaseous wastes;
- High-temperature pyrolysis - is the decomposition of waste in specially organized conditions for this, after which the resulting composition is burned in a special chamber. This process converts toxic products into less hazardous ones and is the cleanest method of waste disposal from an environmental point of view;
- Plasma-chemical technology - used for the processing of liquids and gases of high toxicity. When implementing this process, not only neutralization occurs, but also further production of a valuable product. A distinctive feature of the presented technology is its high cost and complexity of implementation;
- Recycling - along with positive qualities, this method also has negative aspects. The disadvantages of recycling is the increased dynamics of replacing primary raw materials with waste. Among the most striking examples is the deterioration of the taste of a number of categories of products in the food industry. This technology did not justify itself in the production of cardboard - containers made from such raw materials are of low quality and cannot be used for food products;
- Waste disposal - can be implemented at landfills specially provided for this, as well as in underground storage facilities and quarries. Landfills and other places for waste disposal require special permits, and the zones themselves must be equipped in accordance with a number of environmental safety rules.
Modern technologies for the disposal and processing of solid household and industrial waste
According to experts, since the beginning of the twentieth century. 80 billion tons of solid waste have accumulated in Russia, and another 7 billion tons are added to them annually. The annual amount of municipal solid waste is 130-140 million m 3 , most of which are toxic and especially toxic.
Solid waste disposal.
The proportion of waste that is buried or disposed of in landfills is currently very high. Special landfills, which have been operating for 25 years, alienate significant areas. After the landfill is fully loaded, it is covered with vegetative soil, the surface of which can later be used for parks, gardens, and playgrounds. An anaerobic process occurs in the household and food industrial wastes that are closed from contact with air and are located in the embankments of the landfill, and biogas (a mixture of methane and carbon dioxide) is released, which under certain conditions can be used as fuel. There is such an experience. At a height of backfilling of waste of 7 m or more, this gas is taken using pipes. Additional devices required for biogas extraction and utilization quickly pay for themselves.
Solid Waste Incineration
In the 70-80s, thermal processing of waste was developed by burning them in furnaces at waste incineration plants. Such factories operate in many countries of the world, in Moscow, St. Petersburg, Murmansk and other cities of the country. Existing incineration systems provide a high degree of waste destruction (up to 99%) and allow waste heat to be recovered. However, the disadvantages of such systems are more significant. Firstly, the cost of the incineration process is quite high compared to traditional methods (dumping, dumping into the sea, burial in exhausted mines). Secondly, waste incineration plants are sources of emissions of zinc, tin, cadmium, hydrogen chloride, hydrogen fluoride and other harmful substances into the atmosphere. Among the toxic metals, mercury is especially dangerous, which, due to its increased volatility, easily passes into a vapor state during combustion and is released into the atmosphere. Only appropriate careful sorting and preparation of waste, as well as effective cleaning of flue gases (using electrostatic precipitators) can reduce the level of air pollution.
Solid Waste Recycling
The cycle of substances in nature is an excellent example of waste-free production. Wastes of natural processes (dead wood, leaves, etc.) rot, rot and fertilize the earth in a natural way. Aerobes are microbes that breathe oxygen and convert easily rotting substances into organic fertilizers rich in nitrogen, i.e. - in compost. In this case, thermal energy is released. Nature suggested to people a scheme for the technology of composting household waste.
In 1970, a pilot plant for the mechanized processing of household waste was put into operation in Leningrad. At the initial stage of processing, ferrous metal was separated from the waste mass by electromagnetic separators. Further, the waste was crushed in crushers and entered the rotating drums - fermentors, in which the waste was processed into compost. However, in the processed mass there were also non-compostable elements (polyethylene films, glass, cans, etc.). contaminating fertilizer. It was necessary to learn how to clean the compost.
In the late 70s and early 80s, the second generation of waste treatment plants appeared with improved and improved technology. There are currently nine specialized solid waste processing plants in Russia. A similar plant for the city of Omsk is being designed in St. Petersburg.
The technology of waste processing is as follows. On a wide overpass, garbage trucks drive up to the reception area and unload waste onto eight platforms. Then the waste is loaded into eight heat-insulated drums up to 60 m long, into the internal cavity of which oxygen-enriched air is supplied with the help of fans. When the drums rotate, the waste is mixed and crushed, their specific surface area increases. Constant aeration (0.2-0.8 m 3 of air is supplied per 1 kg of waste) awakens the aerobic microflora to life. Microorganisms (mesophiles) enter the work, heating the mass to 50 0 C. At the same time, another type of microflora actively reproduces - thermophiles, due to which the temperature reaches 70 0 C. An avalanche-like biothermal process disinfects waste for two days. Neutralized waste through a perforated nozzle at the end of the drum is evenly fed to the belt conveyor. But this is not yet compost - there are impurities in the form of glass, pieces of wood, plastic, stones, cans, etc. Next comes cleaning. First, ferrous metal is separated using an electromagnetic separator, which is mounted above the conveyor. This scrap metal enters the storage hopper, is pressed into briquettes weighing 80 kg and sent for remelting. Freed from ferrous metal, the mass continues on its way. From the conveyor, it falls on a cylindrical sieve (screen) with cells with a diameter of 45-60 mm. The screen rotates quite quickly, at 15 rpm, so that the fine particles fall through. and large ones remain above the bars. Both products - above and below the grate - are freed from non-ferrous metal using special installations that create an electromagnetic field, under the influence of which non-ferrous metal objects are thrown aside. Ballistic glass separators are used to isolate glass from compost. The release of compost from the polyethylene film is carried out by a strong air jet. The resulting compost is used in agriculture. But at first, the compost is still immature and for a long time the biothermal process continues in it and the temperature is high. Such compost can be used as a biofuel for soil heating in greenhouses. The cooled and ripened compost is reused in open ground in fields or in urban gardening as an organic fertilizer. For the processing of non-composting fractions, pyrolysis is used - heat treatment without oxygen access. In the process of pyrolysis, a vapor-gas mixture is formed, as well as a solid carbonaceous residue - pyrocarbon, which is used in metallurgy as a substitute for graphite. The economic feasibility of the considered process is obvious, because 20 kg of ferrous metal, 2 kg of non-ferrous metal, 200-250 kg of non-composting fractions and 600-700 kg of compost are allocated from one ton of solid waste. About 200 kg of oil-like oils, 190 kg of gaseous products, 330 kg of pyrocarbon are obtained from one ton of non-compostable fractions.
According to the data for Russia as a whole, only about 5% of waste is processed by the industrial method (at waste incineration and waste processing plants), and the rest is taken to landfills and landfills (authorized and unauthorized). Recently, the problem of processing sludge from water and sewer water treatment plants has arisen.
Methods for recycling waste from polymeric materials.
Waste from polymeric materials is not amenable to natural decomposition and therefore they are strong environmental pollutants. Most polymers burn well, releasing a significant amount of heat and consuming a large amount of air. The energy released can be used. However, when burned, many polymers form harmful gases such as ammonia, nitrogen oxides, cyanide compounds, hydrogen chloride and other substances, which requires additional devices for cleaning and processing gas emissions.
The most common way to dispose of waste from polymeric materials is to bury and dispose of them in landfills. Currently, special polygons for polymeric materials are increasingly being used.
There is experience in processing old polyethylene film and turning it into a new one, as well as obtaining pipes that are not subject to corrosion. The creation of polymers with a controlled service life is an effective, promising way to protect the environment. In a number of countries, special, self-destructing types of packaging have been developed and are already being produced. These are photo- or biodegradable polymers that, under the action of light, heat, atmospheric oxygen or microorganisms, decompose to low molecular weight products without polluting the soil.
| " |
Removal, processing and disposal of waste from 1 to 5 hazard class
We work with all regions of Russia. Valid license. Full set of closing documents. Individual approach to the client and flexible pricing policy.
Using this form, you can leave a request for the provision of services, request a commercial offer or get a free consultation from our specialists.
Mankind is seriously faced with the problem of waste disposal, therefore, all over the world, more and more advanced methods of waste disposal are being developed.
“Recycling” is now such a fashionable foreign word. Unfortunately, it has not yet gained the desired popularity in our country. In developed countries, resource conservation is an important motivation for recycling waste.
Special landfills and engineering landfills for waste disposal have a limited area, in addition, they occupy useful land and harm the environment around them. The problem is not solved by the removal of workings at waste incineration plants. They allow you to reduce the amount of waste, but cause no less harm to the environment, poisoning the air with toxic gases.
The latest efforts of scientists are aimed at developing new schemes for waste disposal, and to introduce new processing technologies by type, hazard class and source of origin. This approach is most effective in terms of environmental protection and rational consumption of exhaustible natural resources. The importance of competent waste processing also has an economic component - it contains useful components, the secondary production of which is much cheaper than primary extraction and processing.
Garbage classification
Types of waste by source of origin
- household
- Organic origin
- industrial production
- Medical
- radioactive waste
Types of waste by state of aggregation
- Solid
- Liquid
- Pastes
- Suspensions
- emulsions
- Bulk
In total, there are 5 hazard classes of waste:
- Working off, which belong to the first class of danger, pose a threat to all life on earth. Even in small quantities, they can lead to death, disability, the birth of sick offspring. Substances such as mercury, polonium, plutonium, lead can cause a serious environmental disaster.
- The second and third hazard classes combine garbage that can cause an ecological imbalance, and it will take decades to restore it. These include chromium, zinc, phosphorus and chlorine compounds, arsenic.
- Low-hazard substances of the fourth hazard class also affect the human body and living beings. The ecosystem after their impact is restored within 3 years.
- There is a fifth class - environmentally friendly garbage, but even in large quantities it can cause damage to the surrounding space.
A variety of working off leads to the need to create progressive methods of primary waste sorting.
Methods for processing household waste
The most significant part of the garbage on earth is MSW. Their source is residential areas and social facilities. With the growth of the world's population, the volume of solid waste is also growing. Currently, there are such types of recycling as:
- Burial at landfills
- Natural decomposition in the natural environment
- Thermal processing
- Isolation of useful components and recycling
burial
Looking at all existing methods of waste disposal, burial is the most common method. It is suitable only for garbage that is not subject to spontaneous combustion. Ordinary landfills are giving way to landfills equipped with a system of engineering structures that prevent contamination of surface and groundwater, atmospheric air, and agricultural land. In developed countries, gas traps are installed at landfills, which are formed during the decomposition process. It is used to generate electricity, space heating and water heating. In Russia, unfortunately, there is a very small number of engineering landfills for disposal.
Most of the workings are various organic residues, they quickly rot in the natural environment. In many countries of the world, household waste is sorted into fractions, their organic part is composted and valuable fertilizer is obtained. In Russia, it is customary to compost an undivided stream of MSW, so it is impossible to use decayed organic matter as a fertilizer.
Thermal processing
Thermal processing refers to the following methods:
- Burning
- Pyrolysis at low combustion temperatures
- Plasma treatment (high temperature pyrolysis)
The process of thermal processing allows you to completely destroy harmful components, significantly reduce their number in burial sites, convert combustion energy into heat and electricity.
Simply incinerating garbage is a cheap way to dispose of it. In this area, proven methods of waste processing are practiced, serial equipment is produced, a high level of automation puts the process on a continuous flow. However, combustion produces a large number of harmful gases with toxic and carcinogenic properties. Gradually, the world is moving to pyrolysis.
The most effective is high-temperature pyrolysis - plasma treatment. Her virtues:
- No need to sort leftovers
- Getting steam and electricity
- Obtaining a liquid residue - pyrolysis oil
- Obtaining a harmless vitrified slag at the output, which can be used in secondary production.
- Ecological safety for the environment and human health
Plasma waste disposal methods eliminate the need to create new landfills and landfills, and the economic benefits are expressed in millions of dollars in profit.
In recent years, waste recovery has begun to actively develop, i.e. recycling. Garbage contains many useful components that can be reused for the synthesis of new materials and the production of various goods.
From waste sorted:
- Ferrous, non-ferrous and precious metals
- glass break
- Paper and cardboard
- Polymer packaging
- Rubber
- Remains of wood
- Food leftovers, products with expiration dates
The development of recycling in Russia is hampered by the lack of an established waste sorting system. In developed countries, containers for various types of household waste are installed in the yards, and a culture of waste management is brought up from childhood. Our country has collection points for metals, paper, polymer products, but they cannot seriously stimulate the opening of new recycling facilities. A gradual transition to low-waste and resource-saving production is also desirable.
Disposal of industrial waste
Industrial waste includes:
- Remains of raw materials and materials that are used in production
- By-products of production - garbage, liquids, gases
- Substandard and defective products
- Decommissioned machinery and equipment
Theoretically, any useful component from production waste can be reused. The issue rests on the availability of efficient technologies and the economic feasibility of processing. That is why among industrial wastes, secondary raw materials and irretrievable wastes are distinguished. Depending on the category, different waste processing technologies are used.
Irrevocable waste, where there are no useful components, is subjected to burial in landfills and incineration. Before burial, industrial waste, which contains toxic, chemically active and radioactive substances, is subject to neutralization. To do this, use specially equipped drives.
Subject to centralized collection and neutralization:
- Toxic waste containing mercury, arsenic, lead, zinc, tin, cadmium, nickel, antimony
- Waste from galvanic production
- Organic varnishes, paints, solvents
- Oil products
- Mercury-containing waste
- Waste containing radioactive components
Accumulators are placed in open areas or in underground structures on the territory of enterprises or beyond. For solid waste, tailing and sludge collectors are built, dumps and waste heaps are arranged for waste rocks, ash, and slag. Liquid waste is placed in ponds, settling tanks and burial grounds. After neutralization, hazardous industrial waste is buried in separate authorized landfills.
All industrial enterprises are included in the list of nature users. In this regard, they must comply with the requirements, rules and regulations for waste management, as well as safety precautions, so as not to harm the environment.
The state is trying to encourage manufacturers to introduce low-waste technologies and convert waste into secondary raw materials. So far, this area is developing poorly in Russia.
The main ways of recycling industrial waste:
- Separation of ferrous and non-ferrous metals, industrial alloys, such as win for the purpose of remelting.
- The process of making granules from polymer waste, which is used in the production of the same type of polymer or materials with different properties.
- Crushing rubber for use as fillers, production of building materials.
- Use of wood waste and shavings for the production of finishing boards and paper.
- Obtaining electric current and heat energy from combustible waste.
The problem of industrial waste disposal is very relevant for Russia, where the extractive industries, metallurgy, and petrochemistry are developed, forming a large amount of waste and by-products.
Medical Waste Disposal Methods
Medical waste is a special category. They are formed by medical institutions, pharmacies, pharmacological plants. Approximately 80% consists of ordinary household waste, but the rest can harm the life and health of many people.
Hazardous medical waste includes:
- All items that have been in contact with patients with dangerous and especially dangerous diseases.
- Remains of medicines, disinfectant liquids.
- Remains of equipment that uses mercury salts and radioactive elements.
- Organic waste - biomaterial from pathological and anatomical departments, operating rooms, immunoglobulins, vaccines.
In recent decades, the world has switched to the use of disposable medical instruments made of metal and various types of plastic. After disinfection, they can be sent for recycling after sorting. This judicious use of raw materials will save a significant amount of resources and reduce the cost of producing disposable instruments and patient care items.
Problems of waste disposal and recycling in Russia
The main problems of waste disposal in our country include:
- The presence of many unauthorized dumps.
- Combined waste, for example, mercury lamps can be disposed of like glass - according to the lowest hazard class.
- Placement on a dump of spontaneously combustible waste.
- Modern methods of waste disposal at waste processing plants are too expensive; they are disposed of at landfills much cheaper.
- Weakness of the legislative framework and economic incentives for recycling enterprises. The standard is waste disposal at the enterprise.
- Lack of infrastructure and well-established waste sorting process.
The need to maintain a healthy ecological environment will force government agencies to adopt the experience of developed countries. They will face the need to effectively solve the problems of disposal and recycling of various categories of waste, as well as switch to environmentally friendly production technologies.
INTRODUCTION…………………………………………………………………..2
TYPES OF WASTE…………………………………………………………….4
MODERN PROCESSING TECHNOLOGIES…………………….6
THE CONCEPT OF SAFE PRODUCTION……………………..9
PROCESSING IN THE SARATOV REGION…………………………11
CONCLUSION…………………………………………………………………13
REFERENCES…………………………………………………..14
INTRODUCTION
Currently, the problems associated with the insufficient level of processing, neutralization, and safe disposal of waste exacerbate the environmental and sanitary and epidemiological situation in Russia. According to the state policy in the field of environmental protection of the Ministry of Natural Resources of Russia, the most unfavorable situation is developing in Primorsky, Krasnodar Territories, Moscow, Chelyabinsk, Sverdlovsk, Orenburg Regions, and the Republic of Bashkortostan.
Of the total mass of waste in the Russian Federation, 95% belong to the 5th hazard class and are represented mainly by large-tonnage waste.
The largest volume of production and consumption waste generation falls on the Siberian Federal District - 62%, the smallest - on the South - 0.4%.
Waste - substances (or mixtures of substances) recognized as unsuitable for further use within the framework of existing technologies, or after domestic use of products.
Recycling - reuse or return to circulation of production waste or garbage. The most common secondary, tertiary, etc. processing on one scale or another of materials such as glass, paper, aluminum, asphalt, iron, textiles and various types of plastic. Also, organic agricultural and household waste has been used in agriculture since ancient times.
The recent awareness of the waste crisis facing our society has moved waste management from a side issue to a political debate. For some, the prospect of a major overhaul of the recycling system causes panic, but at the same time a new, more positive attitude towards this problem is being formed. There is a growing willingness to see waste as a source of opportunity and seek solutions from a broader perspective that includes climate change, resource management and urban regeneration.
From the point of view of environmental pollution, the problem comes down to the question of what is waste. From a resource management point of view, this is a question of what waste can be turned into. If we consider waste as pollutants, then they need to be controlled. However, if we consider them as a source of energy and materials, then there are alternative solutions. One such solution is to keep things as they were. Other solutions open the way to something new.
TYPES OF WASTE
Waste classification
Waste varies:
by origin:
Production waste (industrial waste)
Consumption waste (municipal)
By state of aggregation:
gaseous
by hazard class ( for humans and / or for the natural environment)
In the Russian Federation, the following hazard classes for the environment are distinguished:
1st - extremely dangerous
2nd - highly dangerous
3rd - moderately dangerous
4th - low risk
5th - practically harmless
In Russia, there is a Federal waste classifier, in which each type of waste, depending on the source of its origin, is assigned an identification code.
Waste production
Industrial waste - solid, liquid and gaseous production waste obtained as a result of chemical, thermal, mechanical and other transformations of materials of natural and anthropogenic origin.
Waste of certain products - unusable residues of raw materials and / or substances and energy arising in the course of technological processes that are not subject to utilization.
The part of the waste that can be used in the same production is called recyclable waste. This includes the remains of raw materials and other types of material resources formed in the process of production of goods (performance of work, provision of services). Due to the partial loss of some consumer properties, returnable waste can be used in conditions with reduced requirements for the product, or with increased consumption, sometimes they are not used for their intended purpose, but only in auxiliary production (for example, used car oils - for lubricating non-critical components technology). At the same time, the remains of raw materials and other material assets that are transferred to other divisions as full-fledged raw materials, in accordance with the technological process, as well as by-products obtained as a result of the technological process, do not belong to returnable waste.
Wastes that cannot be used within the framework of this production, but can be used in other industries, are called secondary raw materials.
Waste, which at this stage of economic development is inexpedient to process. They form irretrievable losses, they are previously neutralized in case of danger and buried at special polygons.
In industrial ecology, production waste is understood as waste in a solid state of aggregation ( some gaseous and liquid wastes may solidify, for example in filters or sedimentation tanks). The same applies to consumer waste - industrial and household (Fig. 1).
Rice. one. Classification of the main types of solid waste
Consumption waste is products and materials that have lost their consumer properties as a result of physical (material) or obsolescence.
Industrial consumer waste is cars, machine tools and other obsolete equipment of enterprises.
Household waste is waste generated by human activities and disposed of by them as unwanted or useless. Solid household waste includes cardboard, newsprint, packaging or consumer paper, all kinds of containers (wooden, glass, metal), objects and products made of wood, metal, leather, glass, plastic, textiles and other materials that have become obsolete or have lost their consumer properties. broken or obsolete household appliances - garbage, as well as agricultural and municipal food waste - garbage.
A special category of waste (mainly industrial) is radioactive waste (RW) generated during the extraction, production and use of radioactive substances as fuel for nuclear power plants, vehicles (for example, nuclear submarines) and other purposes.
A great danger to the environment is posed by toxic waste, including some of the non-hazardous waste at the stage of their appearance, which acquire toxic properties during storage.
MODERN WASTE PROCESSING TECHNOLOGIES
Modern technologies for processing waste of the agro-industrial complex with the production of biogas
In alternative energy, a special place is occupied by the processing of bio-mass ( organic agricultural and household waste) methane fermentation to produce biogas containing about 70% methane and disinfected organic fertilizers. The most important is the utilization of biomass in agriculture, where a large amount of fuel is consumed for various technological needs and the need for high-quality fertilizers is constantly growing. In total, about 60 varieties of biogas technologies are currently used or developed in the world. Biogas is a mixture of methane and carbon dioxide produced during anaerobic digestion. The residue resulting from the biogas production process contains a significant amount of organic matter and can be used as fertilizer. The production of biogas is economically justified and is preferable when processing a constant stream of waste (effluent from livestock farms, plant waste, etc.). Profitability lies in free raw materials (waste), low-cost organization and management of their supply. The production of biogas is especially effective in agro-industrial complexes, where there is the possibility of a complete ecological cycle.
Obtaining biogas from organic waste has positive features:
1. Biogas can be used to generate heat and electricity with high efficiency;
2. Anaerobic processing of animal waste, crop production and activated sludge makes it possible to obtain ready-to-use mineral fertilizers with a high content of nitrogen and phosphorus components (in contrast to traditional methods of preparing organic fertilizers by composting methods, in which up to 30-40% of nitrogen is lost);
3. The residue is decontaminated and pathogenic microorganisms are eliminated, the waste after anaerobic processing meets the requirements of environmental authorities;
4. Biogas plants can be located in any region of the country and do not require the construction of expensive gas pipelines and complex infrastructure;
5. Biogas plants can partially or completely replace small outdated boiler houses and provide electricity and heat to nearby villages and settlements.
Neutralization of municipal solid waste
At present, the main technological process for the neutralization of municipal solid waste is their incineration in devices of various types. The first enterprise in Russia to implement a four-stage gas cleaning system that meets the requirements of European standards for emissions of harmful substances with flue gases from solid waste incinerators was the Moscow waste incineration plant No. 2 (MSZ No. 2). In the first stage of purification, high-temperature reduction of nitrogen oxides to elemental nitrogen is carried out. In the second stage, the content of dioxins in flue gases is reduced. In the third stage, the process of neutralization of acid gases (HCl, HF) takes place. In the fourth stage, flue gases are cleaned of dust.
Rice. 3. Scheme of the technological line MSZ No. 2
On the rice. 3 the scheme of the waste treatment line is given. Solid household waste is fed through the bunker to the grate of the incineration boiler. Slag and ash formed during combustion are transferred to the slag processing shop. Flue gases from the combustion zone enter the afterburning chamber, where the products of incomplete combustion are additionally oxidized and organochlorine polycyclic compounds are decomposed. The steam generated by waste incineration boilers with parameters of 15kgf/cm2 and 2400C goes to the plant's own needs and is sent to a heat-insulating power plant (TUES).
Tab. 1. Main parameters of operation of waste incineration boilers installed at MSZ No. 2.
|
Flue gas consumption, m 3 / h |
|
Rice. 4. Technological scheme of the flue gas cleaning system from nitrogen oxides.
The developed control system performs the functions of automatic control and automated program-logical control of the process. The solution of these problems is carried out by an intelligent control device - a microprocessor controller. Operating experience of the flue gas cleaning system has shown that this system makes it possible to completely solve the problem and ensure that the concentration of NO in flue gases after cleaning is maintained in the range from 30 to 70 mg/m3.
Recycling of radioactive waste
As another example, it should be said about the processing of production waste, namely radioactive waste.
Russia has developed a technology for plasma-thermal processing of radioactive waste, which is proposed for use in countries where there is a need for the disposal of radioactive waste of low and medium levels of radioactivity. Satisfaction of this need can be demonstrated by the example of Bulgaria. In this country, there are 2 main enterprises that accumulate radioactive and hazardous waste of various origins: the Kozloduy nuclear power plant and the Novi Khan storage facility. At these enterprises, the technology proposed by the Russian Research Center "Kurchatov Institute" has been implemented.
The process of plasma processing of waste consists in the use of plasma arc heaters (plasma torches) to ensure the gasification of organic components, followed by the combustion of the resulting pyrogas, purification of combustion products and the release of neutralized gaseous products into the atmosphere.
Advantages:
high degree of primary waste reduction;
environmental safety of the process;
a small fraction of the radioactivity leaving the reactor in the gas cleaning system;
controllability of the level of radioactivity of the resulting slag.
SAFE PRODUCTION CONCEPT
Due to the constant growth of waste accumulation in the 1980s. the concept of non-waste production appeared. Many institutes were involved in the development of such technologies, but it became clear that the concept is applicable only to a very limited group of industries. In particular, oil refining and petrochemistry cannot be waste-free.
Since all approaches could not radically resolve the escalating ecological situation, at the end of the 20th century. the world community has put forward a completely new concept - a preventive policy. It consists in finding ways to prevent or reduce the generation of waste. This policy is called "Cleaner Production" (CP) and is now accepted worldwide as an innovative concept that can solve the environmental problems of enterprises.
The concept of CP is universal. It is clear that in order to ensure the operation of an enterprise with the least waste and emissions, with low energy costs and high quality of products, a mechanism is needed for the coordinated work of all parts of production. But, as practice shows, in many enterprises each division solves its tasks in isolation.
The essence of CP is the analysis of production efficiency by a working group of employees of the enterprise. The work is carried out in accordance with the methodology developed by the global environmental community in order to identify the causes of significant waste and emissions, poor product quality, as well as to find solutions to improve the operation of the enterprise.
The program usually lasts about a year, as it is necessary not only to identify the causes of problems, but also, with the help of experts, to find the best solution.
It is advisable to dwell in detail on several technologies recommended for implementation.
Two sludge processing technologies are interesting in that one of them is suitable for processing various types of sludge, including old highly stable ones. The technology is a combination of several stages, such as separation, settling, flotation, degassing, conditioning, dehydration, lime addition, compaction, drying. The resulting products are proposed to be burned, extract useful components and used in agriculture, which is not always allowed due to the danger of pollutant migration.
Another technology, developed and used in the USA, uses the cavitation method of separating emulsions with the help of enzymes.
The equipment can be in stationary and mobile forms and is reliable. And although the cost is quite high, the installations are already operating in several places and provide a very high level of water and solid fraction (sand) treatment.
Technologies that use the tornado principle deserve special attention. Firstly, this is a hydrotransport technology that allows pumping sludge, sand, etc. long distances. The installation is small and can be mounted both in a mobile version and in a stationary one.
The second technology allows you to quickly separate a mixture of oil and water using centrifugal force and may be indispensable in the fields. It is already in demand in China, and it is planned to introduce it in Russia.
Possibilities of using industrial waste
In principle, it is possible to use industrial waste in the following main areas:
1. Landscape reclamation, territory planning, backfilling of roads, dams, etc., for which rocks, pebbles, gravel, sand, blast-furnace slag and other types of solid industrial waste are used.
The implementation of this economically profitable area of waste disposal, however, is insignificant - in total, approximately 10% of the volume of available waste is used for these purposes.
2. Use of waste as a raw material in the production of building materials:
1) as porous aggregates for concrete, building ceramics, masonry mortars (waste rock, gravel, sand);
2) as a raw material for the production of white cement, building lime and glass (rocks containing CaCO3 chalk), Portland cement (shale), expanded clay (plastic clay), silicate and building bricks (ash and slag waste from thermal power plants and metallurgical plants), etc.
The building materials industry is the only industry that uses large-tonnage production waste on a significant scale.
3. Recycling of waste as a feedstock, since some wastes are close in their properties to natural raw materials for obtaining a certain substance or raw materials for obtaining new types of products.
In the first case, the principle of low-waste or waste-free production technology is implemented, for example, the production of graphite from graphite ores and the resulting graphite soot.
WASTE PROCESSING IN SARATOV REGION
In the Volga Federal District, the problem of ensuring environmental safety in the handling of industrial and household waste requires an immediate solution. The pace of implementation of sites and technologies for the processing and reuse of the most common waste is very slow, as is the pace of construction of waste disposal facilities, including municipal solid waste landfills in many regions.
Practically for all subjects of the Volga region federation, it is important to resolve issues with solid waste, sewage sludge from sewage treatment plants, banned and unusable pesticides and pesticides.
One of the main ways to solve the problem of waste use is the organization of their collection and processing to obtain marketable products.
The Bulgarian consortium "EcoEnergo" proposes to consider the possibility of cooperation in waste processing in the Saratov region. According to Mikhail Mikhov, the plans of the EcoEnergo consortium include the implementation of projects in Russia for the placement of waste processing complexes with a full production cycle and the creation of a site for deep processing. Saratov is considered as one of the cities where it is possible to place a waste processing complex.
During the presentation, the President of the EcoEnergo Consortium noted that the production process at the company's waste processing complexes is built as follows: at the first stage of production, the incoming waste is sorted, then some of the components (glass, waste paper, plastic bottles, polyethylene, construction waste, etc.) recycled for recycling. The part of MSW that cannot be reused is subject to disposal.
Investors from Foggy Albion intend to build three complexes in Saratov and Engels. The cost of one plant is estimated at about 25 million euros. Two factories in Saratov will practically close all the problems of the city (the third will be in Engels - "SOG"), the management is sure.
The British plan to introduce highly efficient processing technologies - up to 90 percent of the total mass. Although, apparently, this is not the limit - the company intends to process biological waste into alcohol. To do this, the entire "bios" after packaging in polyethylene will be exported outside of Russia. According to the Minister - Chairman Chopin, investors are ready to invest in the project, provided that the city authorities will provide the factories with raw materials for the next 20 years. Actually, this stuff we have, as they say, heaps.
According to the Saratov inter-district environmental prosecutor Alexander Gonchar, in the whole country over the past 5 years, the amount of household waste has increased by 1.5 times. This problem, according to the environmental prosecutor, is also relevant for the Saratov region ( of course, first of all for the regional center with its almost one million inhabitants).
It should only be noted that the "garbage business" has already come to Balakovo and Volsk, where the first sorting complexes in the region have been launched. Moreover, in Balakovo, the plant is the best in the Volga region.
CONCLUSION
The problem of waste recycling has been at the forefront of attention for several years now.
It is no secret that the capacity of landfills for waste disposal is running out. This forces the state to intensify the search for a way out of this situation. However, so far these attempts have not been successful.
As a result, it is worth saying that the main problems in the field of production and consumption waste management are reduced to:
the absence of a unified system of normative acts on the issues of waste management, primarily on their classification and certification;
the creation of specialized industries and the promotion of new technologies is hampered by the lack of legislative mechanisms for economic incentives for enterprises that collect, transport and process waste.
Elementary mechanisms for economic incentives for enterprises in the field of waste management could be:
property tax benefits for facilities used for environmental protection;
a special taxation regime for land tax, VAT and income tax;
application of accelerated depreciation of fixed production assets associated with the implementation of environmental activities.
In view of the foregoing, it seems appropriate:
1. Ensure the creation of a unified system of federal regulations on waste management issues.
2. Develop and adopt a regulatory framework for the creation and implementation of the state waste cadastre as a federal information system in the field of waste management.
3. Prepare regulations on procedures for identifying the best technologies in the field of waste management.
4. Develop economic mechanisms to stimulate waste recycling.
BIBLIOGRAPHY
HE. Kulish, S.A. Kuzhevatov "Purification of flue gases from waste incineration boilers from nitrogen oxides". "Industrial Energy" No. 10-2002, M., Folium, p. 54-59.
Order of the Ministry of Natural Resources "On approval of the criteria for classifying hazardous waste as a hazard class for the environment" dated 15.06.2001 No. 511
SanPiN 2.1.4.1074-01
Catherine de Silgi. Garbage history. M., Text, 2011.
GOST 25100-95* “Soils. Classification". UDC 624.131.3.001.33:006.354 . ISS 13.080. 93.020 OKSTU 5701
V.G. Gnedenko, I.V. Goryachev "Application of plasma thermal technology - a way to solve the problems of radioactive waste disposal." "Conversion in mechanical engineering" No. 6-2006, M., Informconversion, p. 37-41.
S. Zigunenko "Hot drop". M., Firma April, p. 4-5.
V. Sharov “Will waste destroy us or enrich us?”. "Inventor and innovator" No. 4-2005, M., Moskovskaya Pravda, pp. 20-21.
B.E. Shenfeld, A.Z. Oshchepkov "Improving waste management". "Ecology of production", No. 5-2004, M., Industry Gazette, pp. 58-59.
V.S. Dementiev "Waste management in the Volga region". "Ecology of production", No. 5-2004, M., Industry Gazette, pp. 60-61.
D.M. Zobov "Permits for waste disposal: practice and legislation". "Ecology of production", No. 5-2004, M., Industry Gazette, pp. 80-82.
V.A. Sapozhnikov "State regulation of waste management". "Ecology of production", No. 1-2005, M., Industry Gazette, p. 30-36.
S.V. Meshcheryakov, O.A. Khlebinskaya "New technologies in the field of waste management". "Ecology of production", No. 1-2005, M., Industry Gazette, p. 30-36.
MINISTRY OF AGRICULTURE OF THE RUSSIAN FEDERATION
STATE BUDGET EDUCATIONAL INSTITUTION
HIGHER PROFESSIONAL EDUCATION
SARATOV STATE AGRARIAN UNIVERSITY
THEM. N.I. VAVILOVA
LIFE SAFETY
Head of Department:
Teacher:
Modern processing technologies
(by type of waste)
Completed:
4th year student,
faculty
veterinary medicine and
biotechnology
Due to the rapid development of industrial production, humanity faces the need to use new technologies for waste disposal. Today in Russia, about 94% of garbage is simply left at special landfills. In Europe, this figure also leaves much to be desired, although it is much lower (40%). How can the current situation be changed?
Burning
This relatively new technology in waste processing can be considered as sufficiently effective only if a number of mandatory conditions are met. So, for its implementation, it will be necessary to have waste incineration plants equipped with the latest technology. The construction of such enterprises usually takes a lot of money and time (over 5 years). Before the direct start of the process, the garbage must be sorted. Batteries, as well as metal and plastic components, are removed from the total mass.
International research organizations note a number of objective advantages of this method at once, namely:
- Almost complete absence of unpleasant odors.
- A small proportion of toxic substances released into the atmosphere. A study by the journal Waste Management has shown that incineration releases only 3.4 g of dioxins into the air each year, compared to the 1,300 g that occurs in landfills. The UK Environmental Services Association has determined that the technology does not cause mutations in plants grown near processing plants, nor does it cause cancer or respiratory disease in humans.
- The possibility of obtaining a powerful thermal and energy resource base. This is especially relevant when using pyrolysis - a technology in which the combination of low or high temperatures (from 450 to 900 ° or more than 900 °, respectively) with an insufficient amount of oxygen does not lead to the release of harmful and toxic substances, but to the decomposition of the object into its constituent elements. In Russia, this method is still at the stage of development and experimental verification. It is assumed that the introduction of pyrolysis into a permanent practice will provide heat to entire cities with a population of 300,000 people. The enterprises themselves will be able to serve residents for 20 years with an average payback period of 4 years. They also do not have to be supplied with energy for operation, because the synthesis gas produced as a result of combustion will become fuel for reactors.
Burning garbage also prevents the formation of many kilometers of ruins, to which birds and rodents, carriers of infection and viruses, are drawn from the surrounding areas. However, this method requires the mandatory disposal of ash in special storage facilities due to the fact that, containing some impurities of heavy metals, dioxins and mercury, it cannot simply be dispelled or left on the ground.
Plasma processing
The next new recycling technology is one of the safest and most innovative solutions that could be found in this matter. Here, the principle of processing the mass with high temperatures is also used, however, the litter is brought not to decomposition, but to transformation into a gas.
In this state, the former items are distilled into steam, which results in several useful resources at once:
- electricity;
- environmentally friendly slag;
- non-pyrolyzable residues that can be reused for industrial purposes.
Factories operating on the basis of the principle of plasma processing have a closed and cyclical operation: for example, their reactors do not need new energy, because they work on part of their own heat. This system does not require pre-sorting and preparation of the material, because. it is capable of destroying any waste without harm to nature and human health, reducing their initial mass by more than 300 times. None of the currently known disposal methods can demonstrate such an indicator. The use of plasma is also distinguished by minimal costs - getting rid of 1 ton of garbage turns out to be 3 times cheaper than following any other method. That is why plasmatrons are actively used in technologically progressive countries - the USA, Great Britain, Japan, China.
Backfill
Among the technologies for waste disposal, one can also find those that are used not so much because of obvious positive criteria, but because of economic benefits. A striking example of a new method of this kind is the backfilling of a solid waste landfill, which results in the formation of synthesis of gases - methane, carbon dioxide, nitrogen, hydrogen, hydrogen sulfide and oxygen. In other words, the landfill is not just left on the surface of the planet for years, but is buried under a layer of earth and clay for 10-30 years. Over time, non-hazardous natural landfill gas is produced, which is then used to produce fuel, steam, heat and electricity.
Important! The implementation of this method is possible only in the presence of special deep pits, inside which pumping equipment must be installed to transfer gaseous decomposition products to enterprises.
Composting
The latest new recycling technology for household waste is great for organic materials - food residues, vegetation, paper. This disposal method, which is not used in large-scale industry, is a favorite among summer residents and farmers. The composting process consists in the formation of special piles of different sizes, which are regularly turned over (daily, 1 time per month, 1 time per year, etc., depending on the wishes of the person for the duration of composting).
The product obtained as a result of decomposition in natural climatic conditions is actively used as a valuable fertilizer in cultivating land, planting crops and saturating the soil.
Search
We may notify you of new articles,