Since mid-October, Muscovites have been complaining about the smell of burning, smoke and hydrogen sulfide in the air, and last week data appeared about a mercury spill in Moscow. At the same time, official assessments of what is happening run counter to expert ones. For example, officials explain the appearance of a burning smell by burning logging residues and the fight against the bark beetle, and environmentalists claim that “judging by the direction of the wind, the burning of logging residues cannot be the main cause of smoke.”
The situation is similar with the investigation into the circumstances surrounding the appearance of the smell of hydrogen sulfide. The authorities point to the Moscow oil refinery in Kapotnya, while Gazpromneft, which owns the enterprise, continues to deny that the refinery is involved in the spoilage of the city's air.
To clarify the situation at least a little, The Village correspondent Vitaly Mikhailyuk interviewed city activists and experts about which city enterprises most poison their lives.
Waste incineration plant No. 4
Kosino-Ukhtomsky district, Eastern Administrative District
This plant in the east of Moscow, burning up to 250 thousand tons per year, began to be built back in 1996, and launched in 2004. Now, as Alexey Tikhanovich, an activist of the Green Kozhukhovo movement, told The Village, residents of nearby areas are complaining about the sickening smell of burning coming from the plant. The concentration of substances emitted into the atmosphere, according to him, is so high that if people leave the windows open when leaving the apartment, then the clothes in the closets will smell bad. According to residents, the peak emissions occur at night, when most people are already asleep. They claim that they see smoke pouring out of the chimneys, which according to regulations should not happen.
Very close to the main incineration plant was the Ekolog plant, where biological waste, including infected materials and fabrics, was disposed of. According to the Mosekomonitoring station, in neighboring Kozhukhov the main excesses of air pollution are for formaldehyde and nitrogen dioxide. “Last year we came across the report of the Department of Natural Resources for 2012. It was written there that in our region, for 183 days a year, excess daily average concentrations were recorded,” says Aleksey Tikhanovich.
Since 2006, Kozhukhov residents began to advocate for clean air in their area. When letters to various authorities, from the government and the prefecture to the Presidential Administration and environmental organizations, did not bring the desired result, concerned residents held a series of rallies. Their activity was one of the reasons why “Ecologist” was closed in the fall. “However, they did not provide us with any documents. I can’t say for sure, but most likely it was transferred to the territory of MSZ No. 4. Moreover, it has always been one enterprise located in different buildings,” believes Sergei Zhukov, coordinator of the Ecopolis project.
According to Zhukov, Muscovites living near the MSZ complain of discomfort and dry airways. However, emissions produced by such enterprises sometimes have a more serious effect. “Based on foreign research, we can say that substances emitted by waste incineration plants cause, in particular, cancer,” says Ivan Blokov, director of programs at Greenpeace in Russia.
On the other hand, the head of the quality forecasting laboratory environment and public health at the Institute of National Economic Forecasting of the Russian Academy of Sciences Boris Revich believes that Moscow’s waste incineration plants are not a threat: “I have research data that I am not inclined to distrust. I believe that Moscow incinerators do not affect the health of residents. In terms of the concentrations that exist there, the situation is quite favorable if we consider it from the perspective of risks.”
Solid waste landfill "Kuchino"
Balashikha urban district, Moscow region
This enterprise is located outside of Moscow, however, located at the very border of the Eastern Administrative District, it has long become an object of hatred for residents of Kozhukhov, Novokosin and Nekrasovka. This landfill was formed back in the 1970s and, according to local residents, it was built then without any modern standards. Ecopolis coordinator Sergei Zhukov in interview The The Village claims that the lack of waterproofing is contaminating groundwater and, consequently, the area's rivers. The danger of a solid waste landfill is that fires occur there due to chemical processes occurring in the body of the landfill itself. Local activists took measurements of radiation levels, but found nothing.
“It is very difficult to conduct any research there. We tried to do something, but the guards attacked us. We talked to people who live in close proximity. They said that at one time there were armed guards around the perimeter near the training ground. The business is profitable, so I think it’s almost impossible to close it,” says an activist from Novokosin.
Boris Revich, head of the laboratory for forecasting environmental quality and public health, calls landfills “a completely old technology.” “Of course, as much waste as possible should either be burned or recycled, but building these Mont Blancs around Moscow is a worthless thing, the most The best way“This is recycling, but for this it is necessary to establish logistics for different types of waste, which is not done in Moscow at all,” the scientist said in an interview with The Village.
Kuryanovskiy wastewater treatment plant
Pechatniki District, SEAD
Interviewed residents of the south-east of the capital named the aeration fields in the Kuryanovo microdistrict, where city wastewater is purified, as another problem. Now they are one of the largest such enterprises in Europe and serve 60% of Moscow. They began to build them here back in 1939, and were launched already in 1950. At that time it was the outskirts of Moscow, and the now densely populated areas of Pechatniki and Maryino were just neighboring villages. Since then, the Kuryanovsky wastewater treatment plant has been a disaster for these areas, aggravating the already unfavorable situation in the South-East Administrative District.
For six years, an initiative group of environmentalists from the district has been pushing for the installation of ASKZA in Pechatniki - an automatic air pollution control station. In the end, the station was installed, but in a place where emissions do not always reach. “At first, it constantly broke down and gave incorrect data, which was explained by the fact that ASKZA overheated. This year we recorded excesses of 30 MAC (maximum permissible concentration) for hydrogen sulfide. I’m already silent that emissions of 10 MPCs happen almost every day,” Maxim Motin, a deputy from the Pechatniki district, told The Village. According to him, all this leads to the fact that residents of neighboring areas suffer from asthmatic and cancer diseases more often than others.
The smell of hydrogen sulfide, which was felt in most areas of Moscow on November 10, is a common occurrence for Printers in the summer. According to the director of Greenpeace programs, the release that everyone is talking about could theoretically have occurred in Kuryanov.
Local residents have repeatedly complained to various authorities. At first, the authorities did not recognize that there was any harm at all from aeration fields. Now residents are being reassured that by 2018, one of the treatment plant blocks will be reconstructed and covered with special ceilings.
Moscow Oil Refinery
Kapotnya district, SEAD
The oil refinery in Kapotnya was one of the first to come under suspicion when hydrogen sulfide smelled throughout Moscow. However, local residents, who created a special group on Facebook “MNPZ” to share news about the plant, claim that they encounter this much more often.
“A group of independent ecologists monitors air pollution measurement stations. As soon as excesses begin, either the electricity or the Internet is cut off. We recorded 22−24 maximum permissible concentrations for hydrogen sulfide. This usually happens on weekends and late at night. Since we mostly have northwest winds, we are the only ones who suffer.
When the south-east wind blew, all of Moscow realized what was happening,” explains Alexey Mazur, a resident of neighboring Lublin, who in 2011, with several supporters, held a picket outside the plant building.
Now, according to official data, the Moscow Refinery is undergoing modernization, which should be completed by 2020 and reduce the amount of harmful substances entering the atmosphere. Alexey Mazur is skeptical about this: “The windows of my apartment overlook the Moscow Refinery, and I can see everything that happens at the plant from the window. It’s especially funny to hear when they say that reconstruction is taking place. If it were happening, I would see it from the window, but nothing happens at all.”
Waste incineration plant No. 2
Otradnoye District, North-East Administrative District
MSZ No. 2 in Otradnoye has less capacity than the other two Moscow waste incineration plants, but causes no less dissatisfaction among the townspeople living nearby. Local residents interviewed claim that contrary to SanPiN standards, which establish a sanitary protection standard with a radius of one kilometer, the nearest houses are located 180 meters from the plant, and 24 institutions for children fall within this very minimum zone.
According to members of the VKontakte community “Let’s close the waste incineration plant in NEAD/Otradnoye,” they are suffocating from the night smell of burning and smog that fills their apartments at night and spoils their health. Muscovites living nearby contacted the prosecutor's office, Rospotrebnadzor, the health department, the prefecture and the government, but received the answer that the plant uses highly environmentally friendly German equipment.
“We are conducting an open collection of signatures for the closure of the MSZ, but only about 30% of residents of nearby neighborhoods know about it,” local resident Dmitry, who lives in Otradnoye and asked not to use his last name, tells The Village. - Many people associate the smell of burning at night with peat fires. Even on frosty January nights, oddly enough.”
At the end of the summer of 2013, Otradnoye was choking from burning, Dmitry contacted Mosekomonitoring, and at his request, inspections were scheduled for the night of August 28. “Until August 25, the plant was smoking with all its might, and two days before the start of the inspection it simply stopped: it turns out that the law obliges the controlling structure to notify the plant several days in advance. We began to breathe fresh air again. Naturally, the results of this check showed that everything was in order. If there was a check at all,” he says.
Photos: 2 - Sergey Mikheev/Kommersant, 3 - Roman Galkin/RIA Novosti, 4 - TASS
Text: Vitaly Mikhailyuk
] waste incineration plants, and it is planned to launch in the near future new project for the construction of a number of such plants across the country by a subsidiary of the Rostec company [ ] . This method allows reducing the volume of household waste for disposal by approximately 10 times [ ], as well as use additional energy from combustion to produce electricity or heat. But the efficiency factor (COP), significantly lower than gas combustion, also remains open questions environmental hazard, since the combustion of chlorine-containing polymer materials leads to the formation of toxic substances, dioxins and furans [ ]
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✪ Waste incineration plant "Energia". Educational film on ecology
Subtitles
Technologies
Exist various technologies waste combustion in waste incineration plants, they are mainly divided according to the type of furnace in which combustion is carried out.
Layer combustion
Layered combustion is characterized by the supply of hot air flow onto a layer of waste loaded onto a grate. There are several types of layered combustion: with a fixed grate, combustion with a fixed layer of waste, with a moving chain grate, with a fixed one.
Fluidized bed technology
In fluidized bed technology, waste is preliminarily separated into homogeneous fractions and then burned in special chambers in the presence of sand, dolomite chips or other absorbent that has high thermal conductivity. During the combustion process, the particles of the layer under the influence of air jets begin to actively move, so this behavior resembles the behavior of a liquid and also obeys the laws of hydrostatics. This method allows you to reduce the emission of toxic substances during combustion. This method is not suitable for the disposal of mixed waste, as it produces a high amount of slag and emissions.
Pyrolysis and gasification
The waste is heated under pressure in an oxygen-free environment. The result is the formation of liquids and gases with a high specific heat of combustion, which can be used as fuel. Pyrolysis is also used for the thermal disposal of hazardous waste. Is one of the most promising.
Dioxin burners
The destruction of the dioxin lattice occurs at temperatures above 1250 C, which must be maintained for at least two seconds. In this regard, volatile gases obtained from waste incineration are passed through a special chamber where they are re-burned to reduce the concentration of dioxins to acceptable levels.
Environmental Safety
At the moment, there is a large number of scientific studies confirming the safety of waste incineration plants for the population, with strict adherence to combustion technologies, as well as studies confirming the danger of emissions from such plants, as well as in the case of emergency situations. in 2015, a study was published in the journal "Waste Management" confirming that waste incineration plants emit only 0.09% (3.4 g per year) of dioxins into the air of the total amount in the air. The most dangerous turned out to be solid waste landfills, which do not comply with the technology of disposal of unseparated waste fractions, and illegal landfills, producing 1300 grams of dioxins per year into the atmosphere. Subject to separate waste collection technologies, landfill disposal is safer than such plants.
In 2015, the journal Atmospheric Environment released a study which showed that in an analysis of 6 waste incineration plants in the UK, it was proven that the presence of thermal waste treatment plants did not lead to increased concentrations heavy metals suspended particles and within a radius of 10 km.
In an analysis of 3 waste incineration plants in the Netherlands over a 10-year period (2004-2013), concentrations of mercury, dioxins and heavy metals in milk and plants grown directly next to the plants were found to be similar to the Dutch average. The proximity of waste incineration plants does not reduce the quality of agricultural products.
Independent Scientific research from the UK Environmental Services Association showed that waste incinerators operating in the UK had no significant detectable effect on the likelihood of cancer, infant mortality and respiratory diseases.
Emissions
Dioxins and furans
When burning waste containing chlorinated plastic, such as polyvinyl chloride, highly toxic substances are released - polychlorodibenzofurans and polychlorodibenzodioxins (furans and dioxins). According to the US Environmental Protection Agency (English) Russian, when burning one kilogram of waste containing chlorinated plastic (it is included in products such as packaging, plastic bottles, linoleum and others), about 40 mcg of dioxins are released.
CO2
As a result of burning one ton of solid waste, approximately the same (1 ton) amount of carbon dioxide is released.
Other emissions
Per ton of waste burned, there is from 4 to 8 m³ of gaseous emissions, which contain oxides of nitrogen, sulfur(IV), sulfur(VI), hydrochloric acid, heavy metals (, cadmium, lead and others) and dispersed dust.
Cleaning
and precipitation), reactor with additional input of active carbon, dust filters. For Russia, it is planned to use dry scrubber technology, in which, due to the tangential swirl of the flow from flue gases and activated carbon, adsorption of harmful substances occurs on the surface of the activated carbon. The advantage of this technology is the absence of toxic Wastewater and the need for subsequent filtration. The disadvantage of this technology is the settling of highly toxic slag, which is difficult and dangerous to dispose of.Waste incineration plants in Russia
Existing waste incineration plants in Russian Federation in terms of their waste disposal technology, they are outdated and are on the border of complying with safety standards. At this moment, it is intended to implement a pilot project for the construction of 4 factories in the Moscow region and 1 factory in the Republic of Tatarstan. Upon completion of this project, the construction of such plants is planned in each region.
The pilot project for the construction of 4 plants in the Moscow region and 1 plant in the Republic of Tatarstan is called “Energy from Waste” and received a negative assessment from the majority of the environmental community of the Russian Federation and some experts on the economic and energy development of the country.
Main reasons for negativity 1. There are other methods for reducing landfill disposal, for example, technologies for separate waste collection, with subsequent processing of recyclable materials into new products 2. The proposed waste disposal method is not promising, it can be successfully replaced by pyrolysis, thanks to which it is possible to achieve greater efficiency for energy production . 3. In Europe, there is a shortage of waste for combustion and energy production, since there is a shortage of natural gas for thermal power plants in some EU countries; it is more environmentally friendly to export waste to other countries than to burn it in the Russian Federation. 4. Most EU countries refuse the proposed technology, and waste incineration plants in general, and recommend that the international community support the initiative to abandon the construction of new waste incineration plants.
Editor's note: There are currently about 400 waste incineration plants (INPs) in the EU countries, most of which are located in France, Germany, Italy and Denmark. Many incinerators in Europe utilize municipal solid waste (MSW) to further generate heat and electricity. For example, in France and Denmark, priority for loading energy sources is given first to MSZ, and only then, as the load grows, are all other stations that burn biomass and fossil fuels loaded. We bring to your attention an article on the operating experience of the first Russian waste incineration plant, which was visited in June 2010 by a delegation of the NP “Russian Heat Supply” (NP RT) and specialists from the Riga heat supply organization JSC “Rigas Siltums”.
Experience of waste incineration plant No. 2 in Moscow
A.S. Lantsev, corresponding member. International Academy of Management, Director of Moscow Waste Incineration Plant No. 2,
B.V. Promyslov, Chief Engineer Moscow waste incineration plant No. 2, State Unitary Enterprise "EcoTechProm", Moscow
Introduction
“Special Plant No. 2” of the State Unitary Enterprise “EcoTechProm”, located in the north of Moscow, was put into operation in 1975 (at that time it was located in an industrial zone on the outskirts of the capital), which became the first waste incineration plant in the territory former USSR, fully meeting all environmental protection requirements in force at that time.
The technological equipment for the plant, consisting of two technological lines with a capacity of 8.3 t/h of solid waste each, supplied by the French company KNIM, made it possible to neutralize 72 thousand tons of household waste per year. Gas cleaning equipment consisted of electrostatic filters that met the standards for emissions of harmful substances in force at that time.
However, over the 20 years of operation of the plant, the requirements for the organization of the waste incineration process and the quality of flue gas purification, environmental safety and technological reliability of the equipment have increased significantly, despite the fact that during this time the city itself has grown, and the incineration plant has found itself in a residential area. Therefore, in accordance with the Moscow Sanitary Cleaning Program, the plant was stopped for reconstruction in 1995.
During reconstruction, the choice to supply the main technological equipment I justifiably chose the same French company, because... Over the 20 years of operation of the plant, there have been no complaints about the technological equipment. Included in delivery
French equipment included three technological lines, consisting of steam boilers with grates for burning household waste, a complete gas purification system, a process monitoring and control system, a continuous environmental monitoring system and overhead cranes. Increasing the number of technological lines from two to three, while maintaining their unit productivity of 8.3 t/h of solid waste, made it possible to increase reliability, ensure stable operation of the plant and increase its annual productivity to 150 thousand tons of solid waste.
A loan for the reconstruction of the plant was issued by one of the French banks for 10 years, during which the Moscow Government returned these funds to the bank. Money including interest.
The performance of the multi-stage gas purification system fully meets the modern requirements of European and Russian standards for flue gas purification, which can significantly reduce emissions of harmful substances into the atmosphere.
A single automated system completely controls the entire technological process, from waste disposal, flue gas purification to environmental monitoring. Thus, the likelihood of operator error and the risk of an emergency situation are reduced to zero.
The steam generated in the boilers is used for the plant's thermal and electrical needs.
energy. Electricity is generated in steam turbines, the surplus of which is sent to the city power grid of Mosenergo OJSC.
The completion of the reconstruction of the plant and its achievement of design capacity in 2001 made it possible to significantly reduce the volume of landfill disposal of solid waste and thereby improve the environmental situation in the capital.
We will consider in more detail the features of the operation of a waste incineration plant below.
Receiving department and receiving bin of solid waste. Household waste is delivered to the plant by road. Upon arrival, garbage trucks are weighed and checked for the absence of radiation emissions, for which four radiological sensors are installed at the weighing point (during the operation of the enterprise, there were a total of 4-5 cases of exceeding permissible radiological standards, there are clear instructions for eliminating such precedents). Having passed the receiving department, the vehicle travels along an overpass to unload into a storage bunker, the volume of which is 39 thousand m 3 . Two overhead grab cranes distribute waste throughout the hopper, mixing it and removing large items from the total mass of household waste, after which the waste is loaded into the receiving funnels of the boilers. The operator controls the cranes and monitors the process of loading waste into funnels, thanks to the available video surveillance capabilities.
Steam boiler with grate for burning solid waste. After loading into the boiler funnel, solid waste is fed by a feeder to the grate, where the combustion of waste occurs (Fig. 1). The feeder and grate are driven by reciprocating hydraulic cylinders. Through the gaps between the grates, primary air heated to + 170 °C enters, which is necessary for burning debris and cooling the grates. Secondary air is supplied through nozzles from a common air intake device on both sides of the boiler furnace.
The gases generated during combustion with a temperature of about 900 °C enter a steam boiler built above the grate, in which heat is recovered and the temperature of the flue gases is reduced to 240 °C. The steam produced in the boiler under a pressure of 15 atm and a temperature of 240 °C is sent to one of three turbogenerators with an electrical power of 1.2 MW each. A third of the electricity produced fully meets the plant’s own needs, and the surplus is supplied to the city electrical network. The balance of electricity generation and consumption is presented in Fig. 2. The generated steam also fully covers the plant’s own needs for thermal energy, the rest of the steam is sent to air condensers, and the resulting water at the outlet of the condensers is again used in the technological cycle.
Slag compartment. The slag formed after burning waste on a grate is sent to a water bath for cooling to a temperature of 50-60 ° C, from where it is unloaded by a special device onto a belt conveyor, with the help of which it is fed into a slag storage hopper. As it moves into the storage bin, ferrous metal is separated from the slag, which is then pressed (Fig. 3) and sold for processing; the annual volume of this metal is about 1.5 thousand tons. The slag makes up 25% of the burned amount of solid waste by weight and 1/12 part by volume. The slag from the storage bin is packaged and sent to our two landfills for disposal, and it can also be used to fill roads or make paving slabs. Thus, virtually waste-free production is realized.
Gas cleaning system. For the first time in Russia, the enterprise has organized a four-stage gas purification system, which fully meets the requirements of European standards for emissions of harmful substances, and in some areas even exceeds them.
Technological equipment for purifying flue gases from the plant's waste incineration boilers, with the exception of nitrogen oxides, was supplied complete with the main equipment by a French company. To purify gases from nitrogen oxides, domestic technology was used, developed and patented by the Russian state university oil and gas named after. THEM. Gubkina.
Flue gas purification begins already in the boiler, which is a kind of first stage of flue gas purification: by optimizing the combustion mode, a temperature of 900 °C is maintained in the radiation part of the boiler, and the flue gases are in this zone for more than 2 seconds, which ensures the decomposition of dioxins (presence of which is the main environmental problem when burning solid waste, therefore it is very important to ensure their decomposition). If the temperature drops below 850 °C, the gas burner automatically turns on, which maintains the afterburning temperature in the desired range.
In addition, to the zone high temperature The boiler is supplied with a steam-urea mixture to suppress nitrogen oxides, the content of which is reduced to 50 mg/m 3, which is 4 times lower than at similar European plants. It is also worth noting the following here, because. The plant is located in a residential area; the Moscow Department of Natural Resources Management and Environmental Protection set an emission limit corresponding to the concentration of nitrogen oxides in flue gases of 50-70 mg/m 3 .
The technological scheme of the system for non-catalytic purification of flue gases from waste incineration boilers from nitrogen oxides, implemented at MSZ No. 2, is as follows. Solid urea from the storage facility is supplied using a screw feeder into a container for preparing a solution, where chemically purified water is simultaneously supplied. The prepared 40% urea solution is automatically pumped into working containers by a signal from the level gauge sensor, then supplied by dosing pumps to mixers, where it is mixed with steam. The resulting reducing mixture is introduced into the design zone of the combustion chamber of waste incineration boilers through a special distribution system.
The process of NOx reduction with urea in the event of excessive consumption of the reducing agent, ineffective mixing of it with flue gases or a decrease in the temperature in the reducing agent input zone below optimal values may be accompanied by the breakthrough of unreacted ammonia, the content of which in the purified gases is regulated in accordance with international standards should not exceed 10 mg/m3.
At a temperature of about 850 °C, the degree of purification is about 60%, with an increase in temperature to 900 °C it increases to 70% and reaches maximum values at 80-85% at a temperature of 970-990 °C.
The concentration of ammonia in purified gases at temperatures above 900 °C, characteristic of the normal operation of waste incineration boilers, does not exceed 10 mg/nm 3 and is, as a rule, 3-5 mg/nm 3.
To monitor the content of nitrogen oxides and ammonia in flue gases, automatic gas analyzers made in Germany are used.
When developing an automated control system for the process of cleaning gases from waste incineration boilers, the features of the technological process of solid waste combustion were taken into account, which result in constant changes over time in the combustion temperature, flue gas flow and NO x concentration.
In this case, the direct control algorithm is unacceptable, because Continuous measurement of the composition and consumption of solid waste, which affects these indicators, is technically infeasible. Therefore, the only possible principle on the basis of which a contour can be constructed automatic control NO x reduction process is the principle of automatic control with feedback according to the adjustable parameter.
The developed control system is a chain of series-connected links: NO x analyzer, microprocessor controller, power amplifier, urea solution dosing pump, mixer, reducing mixture supply pipeline, reaction zone. Such a circuit is available on each of the three production lines of the plant. The operation of all circuits is monitored using a computer, which is an automated operator’s workstation. The operator can change the parameters of each of the control loops and collect data to analyze the process history. The computer also serves for emergency and process alarms and for communication with the plant's process control system.
In terms of main technological indicators (the degree of gas purification from nitrogen oxides and the ammonia content in purified gases), the purification system surpasses foreign analogues, and its cost is approximately an order of magnitude lower. The introduction of this domestic treatment technology at MSZ No. 2 provided cost savings due to the replacement of imported technology of about $3.5 million.
In addition to monitoring the NO x content, the gas analyzer constantly measures the content of NH 3 and SO 2, the concentration of which is within 10 and 30 mg/m 3, respectively, which is almost 1.5 times better than European standards.
In the boiler, due to a change in the direction of movement (up - down) of the flue gases by 180 O, fly ash is partially released, which is removed by a conveyor into the ash removal system. As the flue gases move from the boiler to the second stage of gas purification - the reactor - activated carbon is supplied to them to neutralize dioxins, furans and heavy metal salts. The second stage of purification - the reactor - is a vertical cylindrical gas duct. Here the milk of lime is splashed and the acidic component of the gases is neutralized. The HCl content in flue gases is constantly monitored and is less than 3 mg/m 3 .
Lime milk is prepared in a special installation and pumped to a turbine installed on the reactor head. Due to the high turbine speed (6000 rpm), lime milk is sprayed into the reactor volume and acid gases are neutralized.
After the reactor, flue gases enter a pulse-jet type bag filter, where fly ash, dust and gas purification products (calcium salts formed when flue gases come into contact with lime milk), as well as activated carbon, which is supplied to the flue gases in front of the reactor, are captured. Dust settles on the outside of the hoses, which are cleaned automatically by pulsating air supplied from the compressor room. The dust content after the bag filter is 6 mg/m 3, the same as after a household vacuum cleaner.
After cleaning in a bag filter, the flue gases are removed through a 100 m high pipe (Fig. 4). A gas analyzer is installed in the chimney, which constantly monitors the content of harmful substances in the exhaust gases (Fig. 5), the temperature of which is about 130 O C.
The plant, thanks to the presence of such a gas purification system, is absolutely safe and does not cause any harm to the environment, despite the fact that it is located within the city.
The plant has created a kind of symbiosis of equipment: the main equipment, consisting of three technological lines, including automatic control technological processes, is imported, all other equipment is domestic. This symbiosis has proven itself well over the almost 10-year period of operation of MSZ No. 2. This circumstance allowed us to significantly save on capital costs during the reconstruction of the plant in 2001. Today we are “sitting on imported needles” in terms of servicing the existing automation and control system, because it is protected and classified by the manufacturer, thus, if any automation unit fails, the plant is forced to purchase it abroad, and some of these units are no longer produced, and they have to be manufactured to special order, which significantly increases (3-4 times) cost of nodes. As operating experience shows, the automation system itself becomes obsolete in 5-6 years, and we have been working with it for almost 10 years, and every year the costs of its maintenance increase in proportion to its aging. It was only thanks to the qualified maintenance of the automation system by our specialists that we were able to work on it for such a long period without updating it. Otherwise, as for most of the spare parts of the foreign equipment used, many imported parts (including grate bars) according to our order have been produced for quite a long time at the nearest Russian enterprises. Thus, we managed to almost completely avoid import dependence in terms of the supply of spare parts.
Our company is the only one in the world that successfully utilizes the entire volume of produced ash using domestic patented technology. Ash, passing through the entire gas path of the boiler, adsorbs salts of heavy metals, dioxins and furans, which classifies it as a third hazard class. There is no solution for ash disposal abroad, so in some countries (for example, in Germany) it is buried in special salt mines at a depth of about 300 m, in other (in particular, in France) foreign countries it is buried in special landfills. According to the data at our disposal, only in Austria is the ash of incineration plants used in the process of obtaining the initial mass, from which cement is then prepared, but this share of ash is only 5% (the remaining majority of the ash is buried in salt mines), while in the country there are work to increase the share of ash.
The technology used at the plant makes it possible to neutralize and process ash of the third hazard class into environmentally friendly products - granulate, which has passed all the necessary tests, which is confirmed by a number of certificates received (hygienic, construction). Granulate is an artificial material such as crushed stone with a granule size of 5-20 mm, which can be used as a filler for concrete, as well as for the construction of embankments during road construction (Fig. 6) instead of or on an equal basis with filler of natural origin. The strength of this artificial material is higher compared to natural aggregates. The only drawback of the product obtained from ash is its high cost (9 times higher) compared to traditionally used materials for embankments in road construction.
During the reconstruction of MSZ No. 2, the project provided for the combustion of solid waste with a calorific value of up to 1500 kcal/kg, but over the almost 10-year period of operation of the reconstructed plant, the calorific value of “modern” waste increased to almost 2000 kcal/kg. In this regard, the volume of solid waste combustion in the boiler decreased from 8 to 6.5 t/h, i.e. with an increase in the calorific value of solid waste, the nominal steam output of boilers began to be achieved with a smaller volume of waste combustion. Considering that the primary task of the plant is waste incineration, therefore, reducing the volume of solid waste disposal in these conditions for the enterprise causes certain problems. If the plant's primary task was to sell the surplus generated heat and electrical energy external consumers and there was such an opportunity, then the above circumstance for the enterprise would turn from a disadvantage into an advantage.
To be fair, it should be noted that when developing the plant reconstruction project, it was planned to transfer the generated thermal energy to external consumers. But when deciding whether to receive technical specifications to connect to the city’s heating networks, the city did not need the thermal energy generated at MSZ No. 2, because in Moscow there was a sufficient heat reserve, despite the fact that our enterprise generates thermal energy without burning any fossil fuels (with the exception of a small amount of natural gas, which the enterprise needs mainly when starting up boilers). Natural gas is burned until the combustion temperature in the boilers reaches the required value, after which the gas burners are automatically turned off. In addition, the combustion of natural gas also begins in automatic mode when high humidity waste enters the boilers (usually this occurs during heavy rainfall outside), so as not to “lose” the two-second dioxin zone, on which the effectiveness of reducing the concentration of harmful substances in flue gases depends.
Due to the fact that at the time of reconstruction of MSZ No. 2, the problem of transferring thermal energy to external consumers arose, it was decided to refocus on electricity generation, so three block turbogenerators were installed (Fig. 7) with a capacitor domestic production(which were originally developed for military sea vessels and nuclear submarines), operating respectively in condensation mode.
Thus, today the enterprise fully covers its own needs for heat and electricity, transferring excess electricity to the power grid of Mosenergo OJSC, as mentioned above. Of course, at the first stage there were certain difficulties in obtaining technical conditions for connecting to the city’s electrical grid, but we resolved them through joint efforts with the Moscow Government.
Electricity used for the enterprise's own needs is initially supplied to our 0.4 kV step-down substation. Excess generated electricity passes through a 10 kV step-up substation and then enters the city power grid. We sell excess electrical energy at a tariff of about 0.6 rubles/kWh. Our monthly income from the sale of electricity is about 450,500 thousand rubles.
Sometimes an enterprise completely switches to operating in autonomous mode (having two electricity inputs) without dumping excess electricity into the city power grid, but it is necessary to unload boilers and turbines, because To meet your own needs, you do not need to fully load the energy equipment. For example, during an accident at electrical substation No. 510 “Chagino” in May 2005, when several districts of Moscow were left without power supply, MSZ No. 2 worked in autonomous mode without any failures.
Unfortunately, at the time of the development of the reconstruction project for MSZ No. 2 in the 1990s. the designers decided to use boilers and turbines with low parameters, while the possibility of using equipment with high parameters was not considered, which naturally affected the volumes of heat and electricity generation.
A full load of the solid waste receiving hopper allows the plant to operate for about 3 days, so when carrying out any maintenance work, as a rule, 1 boiler remains in operation, which avoids a complete shutdown of the plant. Preventative work carried out every 5 thousand hours, major renovation- after 85 thousand hours of operation.
In Russia there is no educational institutions, which would purposefully train specialists to work at waste incineration plants (due to their small number in the country).
Considering that with the launch of the plant in 1975 and before its reconstruction, problems arose in terms of qualified operation of the equipment, at the stage of reconstruction of the plant, the new management of the enterprise recruited qualified personnel, the backbone of which were power engineers.
By the time the plant was commissioned after reconstruction, the new personnel were fully trained in the specifics of working at waste incineration plants, so we had no problems with maintenance.
At the insistence of the Moscow Government, in 2007, a French manufacturer of basic equipment conducted a comprehensive audit of MSZ No. 2, which showed that the plant was in excellent condition.
The number of personnel at MSZ No. 2 is about 200 people; at a similar waste incineration plant in France, the number of employees is 60-70 people. But at the same time, we must take into account that all work (repair, routine and others, including cleaning) to service foreign factories is carried out by external companies, while at MSZ No. 2 all this work is carried out by the efforts of the enterprise’s own employees, which ultimately costs us less. And execution individual species Considering the specifics of waste incineration plants, work is not carried out in Russia by any third party organization.
In total, there are no more than 5 waste incineration plants located on the territory of Russia, and some of them are inoperative for various reasons (for example, a plant in Vladimir burned down due to the ignition of garbage in reception department). All incinerators in Russia use foreign equipment (made in France, Czech Republic, Austria) as the main technological equipment.
Despite the small number of operating waste incineration plants in Russia (compared to foreign countries), the relevance of waste incineration is increasing every year, which requires the construction of an additional number of incinerators in the country.
For example, two Moscow landfills will be completely filled over the next 5 years, and there will simply be nowhere to remove most of the waste (about 3.5 million tons of solid waste are generated in Moscow per year). The tariff for the disposal of solid waste at landfills and for its disposal at the capital's waste incineration plants is almost equal: 2000 and 2140 rubles/t, respectively. In Moscow today there are 3 waste incineration plants; according to one of the resolutions of the Moscow Government, the construction of two more plants is planned, but the time frame for their construction has not yet been determined. It is also worth noting that another modernization is planned for MSZ No. 2 in 2011, which, according to preliminary estimates, will increase the plant’s productivity with the transfer of part of the thermal energy to external consumers. The modernization will be carried out at the expense of the investor.
Existing the legislative framework does not allow Russian waste incineration plants to operate as efficiently as they operate in foreign countries, which, in particular, have: preferential taxation to these objects; increased tariffs for the purchase of heat and electricity generated at waste incineration plants. Today in Russia all incinerators operate on a common basis, which significantly affects the development of this area in our country.
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