The following main areas can be distinguished:

1. Soil protection.

2. Protection and rational use of subsoil: the most complete extraction of the main and associated minerals from the subsoil; integrated use of mineral raw materials, including the problem of waste disposal.

3. Reclamation of disturbed territories.

Reclamation - this is a set of works carried out with the aim of restoring disturbed territories (during open mining of mineral deposits, in the process of construction, etc.) and bringing land plots to a safe state. There are technical, biological and construction reclamation.

Technical reclamation represents a preliminary preparation of disturbed territories. Surface leveling, removal of the top layer, transportation and application of fertile soils to recultivated lands are being carried out. Excavations are filled up, dumps are dismantled, the surface is leveled.

Biological reclamation carried out to create a vegetation cover on prepared areas.

Building reclamation- if necessary, buildings, structures and other objects are erected.

4. Protection of rock masses:

Flooding protection - organization of groundwater runoff, drainage, waterproofing;

Protection of landslide massifs and mudflow massifs - regulation of surface runoff, organization of storm collectors. The construction of buildings, the discharge of utility water, and the felling of trees are prohibited.

Solid waste management

Recycling is the processing of waste, with the aim of using the beneficial properties of waste or its components. In this case, the waste acts as a secondary raw material.

According to aggregate state waste is divided into solid and liquid; by source of education- industrial, formed during the production process (metal scrap, shavings, plastics, ash, etc.), biological, formed in agriculture (bird droppings, animal husbandry and crop waste, etc.), household (in particular, precipitation from communal -household drains), radioactive. In addition, waste is divided into combustible and non-combustible, compressible and non-compressible.

When collecting, waste should be separated according to the criteria indicated above, and depending on the further use, method of processing, disposal, disposal. After collection, the waste is recycled, recycled and disposed of. Waste that can be useful is recycled. Waste recycling is the most important step in ensuring life safety, contributing to the protection of the environment from pollution and conserving natural resources.

Recycling of materials solves a whole range of environmental issues. For example, the use of waste paper makes it possible to save 4.5 m 3 of wood, 200 m 3 of water in the production of 1 ton of paper and cardboard and reduce energy costs by 2 times. It takes 15-16 mature trees to make the same amount of paper. The use of waste from non-ferrous metals gives a great economic benefit. To obtain 1 ton of copper from ore, it is necessary to extract from the bowels and process 700–800 tons of ore-bearing rocks.

Waste plastics naturally decompose slowly or not at all.

When they are burned, the atmosphere is polluted with toxic substances. The most effective ways to prevent environmental pollution with plastic waste are their secondary processing (recycling) and the development of biodegradable polymeric materials. Currently, only a small part of the 80 million tons of plastics produced annually in the world is recycled.

Meanwhile, 860 kg of new products are obtained from 1 ton of polyethylene waste. 1 ton of used polymers saves 5 tons of oil.

Widespread thermal processing of waste (pyrolysis, plasmolysis, combustion) with subsequent use of heat. Waste incineration plants should be equipped with highly efficient dust and gas cleaning systems, as there are problems with the formation of gaseous toxic emissions.

Waste that is not subject to processing and further use as secondary resources is subject to burial in landfills. Landfills should be located away from water protection zones and have sanitary protection zones. In places of storage, waterproofing is carried out to prevent contamination of groundwater.

For the processing of municipal solid waste are widely used biotechnological methods : aerobic composting, anaerobic composting or anaerobic fermentation, vermicomposting.



1. Soil protection Soil fertility, soil degradation The main types of anthropogenic impact on soils are erosion (wind and water); soil pollution; secondary salinization and waterlogging; desertification; alienation of land for industrial and municipal construction.

The main types of anthropogenic impact on soils Erosion - destruction and demolition of the upper most fertile horizons and underlying rocks by wind or water flows Industrial erosion - destruction of agricultural land during the construction and quarrying, Military - funnels, trenches Pasture - with intensive grazing, etc.

The main types of anthropogenic impact on soils Secondary salinization and waterlogging Salinization is the process of accumulation of salts harmful to plants in the soil. Secondary salinization develops with excessive watering of irrigated lands in arid regions. Swamping is the process of swamp formation on waterlogged areas of the earth's surface due to difficult flow, rising groundwater levels, and changes in the evaporation regime.

1. Soil protection Desertification is a process of irreversible change in soil and vegetation and a decrease in biological productivity, turning the soil into a desert. The causes of desertification are prolonged drought; soil salinization; lowering the level of groundwater; wind and water erosion; deforestation (cutting down trees, bushes); overgrazing; intensive plowing; irrational water use.

Measures taken to protect soils from degradation 1. Protection of soils from water and wind erosion; ravines) hydrotechnical measures (arrangement of canals, construction of watercourses, etc.).

Measures applied to protect soils from degradation 2. Ameliorative measures to combat salinization and waterlogging. 1) To combat waterlogging, drainage reclamation is used - the interception and discharge of atmospheric slope water, straightening the riverbed to protect against flooding, the construction of dams, water intake facilities, etc. and drip irrigation, drainage works are being carried out.

Measures applied to protect soils from degradation 3. Recultivation of disturbed soil cover. 4. Soil protection from pollution - the use of ecological methods of plant protection. Agrotechnical methods. biological methods. 5. Prevention of unjustified withdrawal of land from agricultural circulation (for construction).

The main methods of household waste collection 1. Collection of waste in special containers 2. The use of pneumatic transport 3. Rafting into the sewer of crushed waste from apartments, hotels, restaurants and other facilities. 4. Waste disposal systems in which its pneumatic transport is combined with crushing and alloying to the sewer.

Processing and disposal of solid waste 5. Waste-free and low-waste production complex processing of raw materials using all its components; creation and production of new types of products, taking into account the requirements of its reuse; processing of production and consumption wastes to obtain marketable products or any useful use of them without disturbing the ecological balance; use of closed systems of industrial water supply; creation of non-waste complexes.

3. Reclamation of disturbed territories Reclamation is a set of works carried out to restore disturbed territories (during open mining of mineral deposits, during construction, etc.) and bring land plots to a safe state. Technical reclamation Biological reclamation Construction reclamation

4. Protection of rock masses Protection from flooding - organization of groundwater runoff, drainage, waterproofing; Protection of landslide massifs and mudflow massifs - regulation of surface runoff, organization of storm collectors. The construction of buildings, the discharge of utility water, and the felling of trees are prohibited.

Lecture No. 6,7

POLLUTION OF THE LITHOSPHERE AND ITS PROTECTION. DISPOSAL AND PROCESSING OF WASTE

Plan

1. Pollution of the lithosphere and its protection: inclusion of pollution in the power circuit; main sources of soil pollution. MPKprod, VDK and DOK. Basic methods of soil protection from pollution.

The operation of roads in winter, associated with the use of special chemicals to clear the road from ice, also negatively affects the condition of the territory adjacent to the road and the storage areas for these chemicals. In cities, every year it is necessary to restore green spaces along the roads that have died as a result of soil salinization.

Pollution of the roadside with oil products, heavy metals, chlorides and other pollutants is exacerbated by soil compaction. As a result, the moisture capacity and aeration of the soil are reduced. Recovery processes occur in compacted soil, especially if the remaining oxygen is displaced by moisture or other soil gases. The reduction of metal ions leads to the formation of mobile toxic compounds that are easily absorbed by plants. On the other hand, the mobility of these compounds leads to their intense leaching, which reduces the supply of nutrients in the soil.

Highways dismember the existing landscape, thereby violating not only its cultural and aesthetic value, but also the established process of animal migration. This leads to the fact that the existing range of some species of animals is sharply reduced, the previously single population is divided into several isolated parts. The number of these fragmented populations may turn out to be below the critical one, and then they are doomed to extinction. Moreover, crossing migration routes is dangerous not only for animals, because their sudden exit onto the road can lead to serious accidents with human casualties.

When laying roads in dry areas, traffic on them leads to strong dust formation. Broad-leaved crops growing in these areas, such as cotton, are susceptible to pests (spider mites) that breed on plants in conditions of heavy dust. To reduce this effect, special road surfaces are used that exclude dust formation.

Pollution of the lithosphere

While air and water pollution can be noticed or detected, soil pollution can remain hidden for a long time. As a rule, people do not come into such close contact with the soil as they do with air or water. The soil is opaque, in most cases it has a significant buffering effect, which allows pollution to remain unnoticed for a long time. But when the adsorption capacity is exhausted, slip – outwardly unexpected pollution of groundwater, even without the introduction of new quantities of pollutants.

It should also be noted that soils have the ability to regenerate. Many soil inhabitants serve as a source of enzymes, in the presence of which harmful substances are broken down faster than in water or air.

For rate degree of soil pollution use the maximum permissible concentrations of chemicals in the soil (MPC). MPCp is the concentration* of a chemical in topsoil soil, which should not cause direct or indirect negative effects on the environment in contact with the soil and human health, as well as on the self-cleaning capacity of the soil.

There are 4 MPC values ​​depending on the route of chemical substance migration from the soil to adjacent environments:

TV - translocation an indicator characterizing the transition of a chemical substance from the soil through the root system into the green mass and fruits of plants;

MA - migratory air index;

MV - migratory water index;

OS - general sanitary an indicator characterizing the effect of a chemical on the self-cleaning ability of the soil and microbiocenosis.

Anthropogenic pollution of the lithosphere

The main sources of pollution are:

· dumps and storages of toxic waste;

· leaking underground storages and pipelines;

· pesticides and fertilizers;

· anti-icing chemicals used in the road sector;

· fuel oil and waste oil used as a means of binding dust on roadsides;

domestic and industrial waste water;

vehicle accidents;

· deposition of toxic substances (eg acid rain and heavy metal compounds) from the polluted atmosphere.

Pollution from household and industrial waste

The general term for all the many materials that we throw away from homes and institutions and commonly referred to as garbage is - municipal solid waste (MSW). In general, the presence of waste indicates that our society violates one of the main environmental laws - the cycle of substances in nature. The situation with waste is currently characterized as a crisis: there is more and more waste, and there are less and less places for their disposal.

The most serious problem associated with landfills is the contamination of adjacent soils and groundwater. When rainwater passes through untreated waste, a particularly toxic filtrate , which, along with the remains of decaying organic matter, contains iron, mercury, lead, zinc and other metals from rusting cans, discharged batteries and other electrical appliances, and all this is heavily seasoned with dyes, pesticides, detergents and other chemicals.

The second problem is the formation of methane. Buried garbage has no access to oxygen. Therefore, its decomposition is anaerobic, and one of the products of this process is biogas, 2/3 consisting of methane. Formed in the thickness of buried waste, it can spread horizontally, penetrate into the basements of buildings, accumulate there and explode when ignited. In addition, methane can spread upwards, poisoning roots and destroying vegetation at the burial site. In a number of cities, this problem is being solved by constructing “gas wells” on the site of landfills that intercept methane, which can later be used as fuel.

Along with landfills, industrial waste disposal poses a serious environmental hazard. Of these, despite the precautions taken, leakage of pollutants with particular toxicity is possible. In Russia, as noted by some researchers, this problem is complicated by the lack of proper control over the movement and disposal of industrial waste.

Pesticide pollution

Human well-being largely depends on pest control. If not for it, we would live in extremely precarious conditions - our health and food supplies would be at the mercy of other organisms. Today, there are many ways to combat pests, but two diametrically opposed opinions prevail in relation to it.

One of them is based on a purely technological approach. It consists in the search for a “miracle weapon”, most often in the form of a chemical invented by man, which is harmful to the organism of a pest.

The second opinion, which is now called ecological pest control, takes into account the need to maintain the overall ecological balance. It places emphasis on protection human, cultivated plants and animals from damage caused by pests, and not on destruction the latter.

Traditionally, people have chosen a purely technological approach. Thousands of chemicals have been invented to kill pests. They are called pesticides (from lat. Pestis - infection and caedo - I kill). Pesticides are classified according to the groups of organisms they affect. Yes, there are insecticides (kill insects) rodenticides (kill rodents) fungicides (destroy fungi), etc. However, none of these chemicals has absolute selectivity for the organisms against which it is designed, and also poses a threat to other organisms, including humans. Therefore, all this is biocides , i.e., substances that threaten various forms of life.

At first, substances containing heavy metals such as lead, arsenic and mercury were used to control pests. These inorganic compounds are often referred to as first generation pesticides. Such compounds can accumulate in the soil and inhibit plant growth. Many soils were so polluted with heavy metals that after 50 years nothing grows on them. In addition, pests quickly developed resistance to these substances, and therefore the effectiveness of their use decreased.

Therefore, new means of pest control were required. They were second-generation pesticides based on synthetic organic compounds.

The problems associated with synthetic organic compounds can be divided into four categories:

development of resistance in pests;

· revival of pests and secondary outbreaks;

rising costs;

undesirable impact on the environment and human health.

The development of resistance in pests is associated with the variability of pest populations; they represent a dynamic gene pool capable of rapidly evolving. Pesticide treatments create selection pressure leading to population resistance.

Over the years, pesticide use has steadily increased the number of species resistant to them. About 25 major pest species have become resistant to all pesticides. At the same time, cases were noted when the resistance of pest populations to chemicals increased at once.

Rising costs are associated with the need to use more and more expensive pesticides, which, however, gives less and less effect.

The problem of the undesirable effects of pesticide use is of the greatest concern to the public. Transmitted and accumulated in food webs, pesticides have spread across the globe. Numerous negative manifestations of the impact of these substances on living organisms, including humans, have been noted. Despite strict controls on the use of pesticides, the problem will continue as long as there are agricultural practices based on their application.

Heavy metal pollution

Pollution with heavy metals significantly affects the soil ecosystem. Lead has a clear tendency to accumulate in the soil, since its ions are inactive even at low pH values. For various soils, the rate of lead leaching ranged from 4 g to 30 g per hectare per year.

The soil becomes dead when it contains 2...3 g of lead per 1 kg of soil. Around some industrial enterprises, the content of lead in the soil reaches a concentration of 10...15 g/kg. According to some reports, the content of lead on the soil surface at the edge of the right of way of highways is usually up to 1 g / kg, but in the dust of city streets it can be 5 times higher [[i]].

Plants are more tolerant of lead than animals and humans, so the lead content of plant foods must be carefully monitored.

Unlike lead, cadmium ions are highly mobile, especially in acidic soils, so accumulation of this metal is not observed in most cases. Cadmium is introduced into the soil from the air, either together with combustion products, or with phosphorus-containing fertilizers as an impurity.

The mobility of copper ions is even higher than that of cadmium ions. This creates more favorable conditions for the assimilation of copper by plants, as well as the leaching of this substance from the humus layer. Although copper in trace concentrations is considered essential for life, toxic effects in plants appear at a content of 20 mg per kg of dry matter. Copper has a toxic effect on microorganisms, while a concentration of about 0.1 mg / l is sufficient.

Zinc is also a relatively mobile element in the soil. Zinc is one of the most common metals in technology and everyday life, so its annual application to the soil is very large. The soil near zinc processing plants is especially contaminated.

The solubility of zinc in soil begins to increase at pH values ​​less than 6, so zinc does not accumulate in acidic soils. At pH values ​​greater than 6, zinc accumulates in the soil due to interaction with clays. For plants, a toxic effect is created at a content of about 200 mg of zinc per kg of dry matter. The human body is sufficiently resistant to zinc and the risk of poisoning when using agricultural products containing zinc is low.

Protection of the lithosphere

Chemical and biochemical changes in soils and their significance for plants, soil inhabitants, and also for humans should not be considered in isolation or over historically short periods of time. The soil takes part in the formation of local climatic conditions. The elimination of the soil cover leads to the disappearance of vegetation, which leads to the formation of dry deserts, as happened in northern Africa (Sahara Desert). Mankind needs to realize the importance of preserving the soil as the basis of its existence and move on to new methods of management that ensure sustainable existence and development.

Soil erosion prevention.

Consider separately the traditional and new methods of soil protection from erosion.

traditional methods.

· Contour plowing (furrows directed perpendicular to the slope).

· Narrow-band sowing (alternating strips of plowed and uncultivated land).

· Protective forest plantations.

Terracing (decoration of slopes in the form of steps).

New methods.

Tillless farming . The purpose of plowing and cultivating the soil is to control weeds. The alternative is chemical herbicides(poisons for weeds), first created in the early 60s. This method has both positive and negative sides. The benefits include saving time and energy - instead of three passes of the technique, one is enough. In addition, since the herbicides are sprayed from the air, there is the possibility of early sowing, and, therefore, a second harvest in one season. These are purely economic reasons for using this method. But it also has environmental benefits: without ploughing, soil structure is preserved, detritus is supplied and, most importantly, erosion is prevented, since the surface of the earth is almost always covered with vegetation.

However, there are strong arguments against this method. First, the use of herbicides may not be safe for humans. Secondly, it is necessary to periodically increase the doses of chemicals or develop new substances, since weeds gradually develop resistance to the herbicides used. Thirdly, the absence of plowing favors the reproduction of agricultural pests living in the soil, which, in turn, causes the need to treat the field with pesticides. In general, the amount of all kinds of chemicals used in no-till farming is 2-6 times more than in traditional farming.

Another possibility to prevent soil erosion is the gradual transition of agriculture from annual crops on perennial. In this case, the need for annual plowing would disappear altogether. The main difficulty here lies in finding and cultivating suitable plant species.

Proper organization of agriculture and forestry plays a huge role in protecting soil from erosion. Here the main points are grazing restriction, reforestation and soil recultivation. When applying irrigation, it is necessary to choose water saving irrigation schemes and provide for mandatory drainage, necessary for "washing" the soil from excess salts (in this case, however, there is a problem of further use of washing water).

Waste control.

The best way to deal with waste is not to produce it at all. Therefore, any state that cares about its future should develop a strategy aimed at stimulating the reduction of the volume of waste produced, recycling of waste, the creation of waste-free technologies, and the use of biodegradable chemicals.

Waste reduction

Over the years, the amount of MSW has steadily increased: partly due to population growth, but mainly due to changing lifestyles of people using more and more wrapping and packaging materials, disposable goods. It is possible to significantly reduce the amount of waste by increasing the service life of goods. B. Nebel's book describes an example of using disposable and reusable bottles. It shows that the promotion of reusable bottles, adopted in some US states, not only reduces the amount of waste, but also leads to the growth of local industry and employment.

You can also reduce the amount of waste by lowering the material intensity of goods, reducing their size, and increasing their service life.

Recycling

Industrial waste is divided into solid (metals, wood, plastics, etc.) and liquid (sewage sludge, oil products).

The choice of waste treatment method depends on the type and quality of the waste. Homogeneous waste is easier to recycle. For example, scrap metal and waste after sorting and baling on presses are sent for remelting; waste wood is used for the manufacture of chipboard and fiberboard; slag - for the manufacture of building materials; oil products are recycled, etc. Some types of waste containing toxic substances or valuable materials are subjected to special treatment at landfills.

At present, it is of great benefit waste exchanges, where enterprises can repurchase production waste from each other to use them as raw materials.

Heterogeneous waste is in most cases not economically feasible to process and such waste is considered garbage, the main method of use of which is incineration. A large amount of waste is currently not recycled due to the unprofitability or lack of recycling technologies. They are either buried or stored. Finally, many disposable firms are interested in the current situation, as it allows them to earn income indefinitely.

But, nevertheless, there are many ways to recycle various types of waste. Many firms are investing in recycling because recycling is cheaper, reduces energy costs (for example, remelting aluminum cans can reduce energy consumption by 90% compared to the bauxite method), reduces the need for refining equipment, and increases equipment life. All this suggests that the possibilities of making a profit from municipal solid waste are inexhaustible.

2. Waste disposal and recycling

solid waste industrial enterprises are very diverse both in their properties and in their impact on the environment. They consist, as a rule, of active substances, which, accumulating in soil, groundwater and the atmosphere, gradually pollute them and cause undesirable effects.

Waste- these are wastes of production, household, transport, etc. that are not used directly in the places of their formation, which can actually or potentially be used as products in other sectors of the national economy or in the course of regeneration. Hazardous waste must be neutralized, and unused waste is considered garbage. Waste can be (Fig. 8.4):

Fig.8.4. Main types of waste

1. Household (communal) solid (including the solid component of wastewater - their sludge) waste that is not disposed of in everyday life, resulting from the depreciation of household items and the very life of people (including baths, laundries, canteens, hospitals, etc.). The problem of household waste is currently very acute in many countries of the world. Thus, about 150 million tons of waste are generated annually in US cities, and by the year 2000 their volume is expected to increase by another 20%. In Japan, the amount of household waste exceeds 72 million tons annually. In the former USSR, in 1985, 217 million m3 of household waste was removed from cities by special vehicles, and in 1988, already 228 million m3. Therefore, for the destruction of household waste abroad began to build powerful incinerators (up to 900 tons or more waste per day) to generate energy. The share of incinerated waste is: for the USA - 3%, Japan - 26%, Germany - 34%, Sweden - 51%, Switzerland - 75%, etc., and only a few of the plants produce electricity. Most incinerators generate steam, which is fed through steam pipelines to neighboring industrial plants or residential areas. In our country, in 1988, 1416 thousand tons of household waste were taken to waste processing plants (that is, ~ 0.5%).

2. Production waste (industrial)- the remains of raw materials, materials, semi-finished products formed during the production of products or the performance of work and have lost their original consumer properties in whole or in part. They can be irretrievable (technological losses: volatilization, waste, shrinkage) and returnable. So far, production waste in Russia is significant: in mechanical engineering and metalworking, the share of metal waste in the total consumption of ferrous metals amounted to 21%, and the share of chips in the formation of metal waste reached 42%. Every year, a significant amount of waste is also generated in the EEC countries: processing industry - 400 million tons, industrial enterprises - 160 million tons, etc. Of the total amount of waste (~ 2.2 billion tons), half is agricultural waste. However, if in the EEC countries 60% of household waste is disposed of, 33% is incinerated and 7% is composted, then over 60% of industrial waste and 95% of agricultural waste are intensively processed (according to foreign sources).

3. Industrial consumption waste- machines, tools, etc., unsuitable for further use for their intended purpose and decommissioned in the prescribed manner. They can be agricultural, construction, industrial, radioactive, the latter are very dangerous and need to be carefully buried or decontaminated.

In recent years, there has been an increase in the number dangerous (toxic) waste - capable of causing poisoning or other damage to living beings. These are, first of all, unused various pesticides in agriculture, industrial waste containing carcinogenic and mutagenic substances, etc. In the USA, 41%) of municipal solid waste (MSW) is classified as "especially hazardous", in Hungary - 33.5%, while in France - 6%, Great Britain - 3%, and in Italy and Japan - only 0.3%. In Russia, 10% of the total mass of MSW is classified as hazardous waste. In many countries of the world, the amount of hazardous waste is steadily increasing (Table 8.2).

Table 8.2

Hazardous waste production in various countries

	Hazardous waste, thousand tons
early 80s	late 80s
Germany (without the GDR) Great Britain World (overall)

On the territory of Russia there are so-called chemical "traps", that is. long-forgotten landfills of hazardous waste, on which residential buildings and other objects were built over time. Over time, they make themselves felt by the appearance of strange diseases among the local population, but their registration has not yet been carried out. Accounting for such burials in the United States showed that there are at least 32 thousand potentially dangerous; in Germany, about 50 thousand such sites were identified, in the Netherlands - 4000, and in small Denmark - 3200.

Approximately 85 sites of nuclear explosions for peaceful purposes carried out on the territory of Russia can be similar traps. Since the 1960s, 47 underground nuclear explosions have been carried out in the Caspian region for technical purposes (deep seismic sounding, to increase oil recovery, to create underground tanks in salt domes, etc.).

Waste radioactive are by-product biologically or technically harmful substances that contain radionuclides formed as a result of human activity. Radioactive waste (RW) is dangerous primarily because the radionuclides contained in it can disperse in the biosphere and cause various genetic changes in the cells of living organisms, including humans. They are classified according to various criteria: state of aggregation, half-life, specific activity, radiation composition, etc. .

Among the radioactive waste in terms of aggregate state, the most common are liquid, which occur at nuclear power plants, at radiochemical plants, and in research centers. The amounts of solid radioactive waste are also significant, in particular, in nuclear power plant reactors with a total electric power of 1 GW, 300-500 m3 of solid waste is generated per year, and from the processing of irradiated fuel another 10 m3 of high-level, 40 m3 of medium-level and 130 m3 of low-level waste.

Currently landfills for solid waste disposal must be designed and equipped in accordance with the following rules:

· new landfills should be created on elevated sites with deep groundwater; often soil is removed from the top of the hill, which is subsequently used for backfilling waste;

· around the perimeter of the landfill, ceramic pipes should be dug to collect water and leachate, and its bottom should be covered with a waterproof layer of clay or plastic at least 20 cm thick; a layer of coarse gravel and a layer of porous soil are laid on top of it; all this is designed to ensure that the filtrate, having reached the impervious layer, flows through the gravel into the collector system, and then undergoes appropriate processing (Fig. 4);

· the layer of gravel surrounding the landfill also serves to divert the resulting methane;

· layer-by-layer stacking of waste continues until the burial looks like a pyramid; with this form, infiltration is minimized, and consequently, the leaching of substances from the garbage;

Finally, monitoring wells are installed along the perimeter of the landfill for periodic monitoring of the quality of groundwater.

A more expensive way to dispose of solid waste is to burning to receive electricity. In this case, modern gas cleaning equipment* should be used to prevent air pollution. Of particular concern is the fact that the incineration of MSW generates dioxins are extremely hazardous and persistent substances capable of bioaccumulation and bioconcentration. It should be noted that this approach does not completely solve the problem of disposal, since the ash remaining after incineration is about 10-20% of the initial volume of garbage.

Municipal landfills are not allowed to dispose of hazardous chemicals. If it is impossible or inexpedient to process them, they resort to burial.

There are three most common disposal methods for hazardous waste. The first of these provides injection of liquid waste into a deep well drilled below the level of impervious rocks. In this case, after sealing the well, conditions are created for long-term storage of pollutants.

The second method is the storage of liquid (non-volatile) waste in special settling ponds to prevent leakage of contaminants.

The third, most expensive, method is used for the disposal of very toxic and radioactive substances. It provides for the construction of special burial grounds, including waste storage tanks, protective rooms, monitoring system, alarms and other precautions.

However, none of these methods can guarantee 100% isolation and security. Therefore, it is necessary to strive to minimize the amount of waste generated.

Now hopelessly outdated methods of radioactive waste management are used: high-level wastes are concentrated and isolated, medium- and low-level wastes are diluted and sprayed, polluting the environment. The most acceptable option for solving the problem of waste is to bury them to a considerable depth in the earth's crust. Thus, high-level waste is most often stored in surface or underground containers (mines, adits, mainly in rock salt, wells in rocks, etc.). For example, in the United States, radioactive waste is buried in salt mines and rocks, in Sweden - in underground storage facilities in granites, where containers with waste are stored in large bathrooms filled with distilled water, etc. In our country, waste waste is concentrated at nuclear power plants or in separate storage facilities where the "fuel" is aged, significantly reducing its radioactivity. On the territory of Russia there are 15 landfills for RW disposal.

In Russia there are large centers for the disposal of liquid RAO and their burial (Chelyabinsk-65e Krasnoyarsk-26, etc.). Unfortunately, the existing methods of neutralization (cementing, vitrification, bituminization, etc.), as well as the burning of solid RAO in ceramic chambers (NPO "Radon") radioactive waste poses a significant danger to the environment. So, at the Mayak training ground (near Chelyabinsk), up to. 100 million curies of liquid radioactive waste, some of which are simply dumped into water bodies: more than 3 million hectares of land have already been polluted. This area has become a zone of ecological disaster, where oncological diseases have increased by 2 times, the incidence of childhood leukemia by 66%, etc.

Storage tanks are used to prevent contamination of groundwater and surface water sources. They use impervious devices that ensure the reliable operation of structures and exclude the leakage of waste fluid. The type of reservoir is determined by the nature of the wastewater or solid waste.

There are accumulators of liquid single-phase effluents: storage ponds, evaporation ponds, settling tanks, filtration fields; accumulators of two-phase effluents: tailings and sludge storages, hydraulic ash dumps and solid waste accumulators: ash dumps, sludge collectors, etc.

Accumulators of liquid single-phase drains. Intensely colored industrial wastewater with a strong odor containing a large amount of salts is sent to these accumulators. With a high content (more than 100 g/l) of homogeneous salt in the waste water, it is advisable to evaporate it in order to extract the salt. Industrial wastewater containing a large amount of organic substances that cannot be extracted and used, and waste acids (sulfuric, nitric, hydrochloric) in various proportions, is also sent to these accumulators. In some cases, it is possible to send wastewater containing only mineral salts to storage tanks, the extraction of which, despite their high concentration, is impractical due to the impossibility of application.

In order to avoid overflow, it is impossible to send slightly polluted effluents to the reservoirs, which are subject to unhindered or after treatment at the treatment plant, discharge into the reservoir, as well as. too concentrated wastewater, such as 20% sulfuric acid.

The scheme of the storage pond-evaporator is shown in fig. 7.3. It is based on an embankment dam, an impervious curtain made of waterproof material, buried to a layer of clay. The design of the pond to a large extent depends on the terrain, geological structure and hydrological conditions of the area. Depending on the relief, ponds can be ravine, flat, floodplain, slope and pit.

Rice. 8.6. Storage pond-evaporator: 1 - embankment dam; 2 - the maximum calculated level of effluents; 3 – water horizon (HW) in the lake-saline marsh before the construction of the pond; 4 - impervious curtain of bentonite clays; 5 - clays; 6 - sands; 7 - loams; 8 - soil

Ravine Ponds they are placed in gullies and ravines with a blocking dam in their lower part and with special spillway structures designed to pass the natural runoff of rain and melt water. Discharge devices are made in the form of a bottom pipe or tunnel. Plains drives arrange on flat areas, dike them around the entire perimeter, or in artificially created recesses-capacities. floodplain ponds are built in the floodplains of the rivers by embanking a section of three sides. In the same way, drives are created on slopes. Pit storages arrange in the workings of old quarries or reserves.

Soils have different throughput capacity, characterized by the filtration coefficient Kf . The filtration coefficient is the filtration rate through a unit cross-section of the soil with a hydraulic gradient equal to one. The filtration coefficient is the main characteristic of the water permeability of soils. In table. 8.3 shows the values ​​of Kf for various soils.

Table 8.3

Physical characteristics of soils used for the construction of reservoirs

	Bulk density, g/cm3	Density, g/cm3		Water permeability
Loam				permeable Semi-permeable Waterproof

The most radical means used to protect groundwater and reservoirs from pollution are the interception of filtered effluents by drainage and the installation of impervious curtains and screens.

Anti-seepage devices are designed to reduce filtration through a dam or dam and increase its stability, eliminate dangerous filtration deformations of the soil and completely retain sewage water. For their construction, coatings with poorly permeable soils (clay, loam), bitumen, concrete, polymer films, etc. are used.

Accumulators of two-phase drains. Two-phase effluents are aqueous suspensions of mineral and organic substances of various compositions. The concentration of the solid phase in them ranges from 20 to 100 g/l. This, as a rule, is waste from the processes of purification and preparation of waste and natural waters, the main technological processes. They are sent to a tailing dump or a sludge dump. In these accumulators, the sediment is separated and clarified water is obtained. tailings is a piece of terrain fenced off by a dam or dam (Fig. 8.7). A dam or dam is built in bulk or alluvial way.

Rice. 8.7. Tailings dam: 1 - dam of the first stage; 2 - secondary dams; 3 - dam of the second stage

As the fenced-off area fills up, secondary dams are built. These dams are built in bulk from imported materials. At high pressures on the dams and the presence of strongly filtering gr. high fur boots arrange discharge drainages. As pulp is supplied to the tailings, the water level in their clarification ponds rises all the time, the location of the pond and its size change within the storage facilities.

Tailings dumps occupy vast areas, measured in hundreds of hectares; their depth reaches hundreds of meters, and the depth of the water layer, depending on the conditions of pulp supply and clarified water intake, is 0.5-1.5 m.

Sludge storage- large earthen ground structures with a volume of up to tens of millions of cubic meters and a depth of up to 50 m, their service life exceeds 10 years. They are created in the water supply and sewerage system of chemical and petrochemical enterprises. They are placed on flat flat areas of the terrain (in floodplains, on terraces) and bunded from all sides. or partially in areas of local relief depression.

Sludge storages are also located in gentle ravines and gullies. Embankment dams and blocking dams are built in bulk from loamy materials. You can also use the sludge washed into the sludge storages. The sludge pulp is supplied to the sludge storages according to the same schemes as the tailing pulp to the tailings.

According to the conditions of waste storage, sludge storages are divided into alluvial and liquid. For bulk sludge storages, earthen dams are preliminarily built to the full height of the designed tank or to a part of this height. Most often, fill dams are erected, and fill dams are less often provided.

A road and slurry pipelines are laid along the crest of the dam. The crest of the dam should have a protective coating and a system of ditches for organized collection and disposal of surface water. Sludge storages can occupy a different area and working volume. On average, the area of ​​the sludge reservoir is 10-20 ha, the amount of sludge discharged, ths. t per year.

Solid Waste Accumulators designed to collect sludge from general plant treatment facilities, clean brines, slag materials, ash, etc. These earthworks are similar to tailings and sludge storages.

On fig. 8.8 shows a diagram of a sludge collector. The area of ​​the land plot occupied by it is about 5 hectares, the depth is 10 m. In order to prevent storm and melt water from entering the sludge collector from the catchment area, in places where surface water can be directed, an enclosing embankment 4 m wide along the ridge is arranged. To prevent contamination of groundwater with excess moisture sludge, provide an impervious screen. The same screen is arranged on the leveled surface of the sludge.

Rice. 8.8. Solid waste sludge accumulator: 1 – bowl; 2 - overpass; 3 – storage slopes; 4 - forest plantation; 5 - drainage ditch

The screens consist of two layers: the lower one (two layers of polymer film 0.2 mm thick) and the upper one (ground-polymer layer 0.6 mm thick). The soil-polymer layer is obtained by spraying a solution of synthetic fatty acids heated to 80°C over the prepared soil layer.

For environmental purposes, to control the operation of the impervious screen and the quality of groundwater in the area of ​​the sludge dump, wells are drilled to take water samples for chemical analysis.

In order to prevent dusting of the upper dried layer of sludge and to create a natural fence around the area of ​​the sludge reservoir, a forest belt of trees and shrubs is provided. In order to prevent domestic animals from entering the territory of the sludge collector, it is fenced with barbed wire on reinforced concrete posts.

The sludge is transported to the sludge accumulator after being processed at the station for mechanical dehydration of general plant treatment facilities by dump trucks, followed by dumping into the sludge accumulator from overpasses and the crest of the enclosing embankment. After filling the sludge reservoir and the device of the upper screen, a layer of local sandy soil 0.6 m thick is poured on top and a layer of local soil and vegetable soil 0.5 m thick is poured over it. After the above work is completed, the sludge reservoir site is returned to agricultural circulation.

* usually expressed in mg per kg of soil.

* The cost of such equipment sometimes reaches half of all costs for the construction of the plant.

test

QUESTION 2. METHODS FOR PROTECTING THE LITHOSPHERE

In the internal structure of the Earth, three main layers are distinguished: the earth's crust, mantle and core.

The earth's crust is located on average to a depth of 35 km (up to 5-15 km under the oceans and up to 35-70 km under the continents). The composition of the earth's crust includes all known chemical elements. O (49.1%), Si (26%), Al (7.4%), Fe (4.2%), Ca (3.3%), Na (2.4%), K (2 .4%), Mg (2.4%).

The mantle is located between the earth's crust and core and extends to a depth of 2900 km. O, Si, Fe, Mg, Ni predominate here. Inside the mantle, from a depth of 50-100 km under the oceans and 100-250 km under the continents, a layer of matter begins in a state close to melting, the so-called asthenosphere. The earth's crust, together with the upper solid layer of the mantle above the asthenosphere, is called the lithosphere.

The lithosphere is the outer hard shell of the globe. This is a relatively fragile shell. It is broken by deep faults into large blocks - lithospheric plates, which slowly move along the asthenosphere in a horizontal direction.

The core is located below the mantle at a depth of 2900 km to 6371 km. It consists of Fe and Ni.

The lithosphere is a stone shell of the Earth, including the earth's crust with a thickness (thickness) from 6 (under the oceans) to 80 km (mountain systems). The upper part of the lithosphere is currently subjected to ever increasing anthropogenic impact. The main significant components of the lithosphere: soils, rocks and their massifs, bowels.

Causes of violation of the upper layers of the earth's crust:

mining;

disposal of domestic and industrial waste;

conducting military exercises and tests;

fertilizer application;

application of pesticides.

In the process of transforming the lithosphere, man extracted 125 billion tons of coal, 32 billion tons of oil, and more than 100 billion tons of other minerals. More than 1500 million hectares of land have been plowed up, 20 million hectares have been swamped and salinized. At the same time, only 1/3 of the entire extracted rock mass is involved in circulation, and ~ 7% of the production volume is used in production. Most of the waste is not used and accumulates in dumps.

Lithosphere protection methods

The following main areas can be distinguished:

1. Soil protection.

2. Protection and rational use of subsoil: the most complete extraction of the main and associated minerals from the subsoil; integrated use of mineral raw materials, including the problem of waste disposal.

3. Reclamation of disturbed territories.

Reclamation is a set of works carried out with the aim of restoring disturbed territories (during open mining of mineral deposits, in the process of construction, etc.) and bringing land plots to a safe state. There are technical, biological and construction reclamation.

Technical reclamation is a preliminary preparation of disturbed areas. Surface leveling, removal of the top layer, transportation and application of fertile soils to recultivated lands are being carried out. Excavations are filled up, dumps are dismantled, the surface is leveled.

Biological reclamation is carried out to create vegetation cover on prepared areas.

Construction reclamation - if necessary, buildings, structures and other objects are erected.

4. Protection of rock masses:

Flooding protection - organization of groundwater runoff, drainage, waterproofing;

Protection of landslide massifs and mudflow massifs - regulation of surface runoff, organization of storm collectors. The construction of buildings, the discharge of utility water, and the felling of trees are prohibited.

Solid waste management

Recycling is the processing of waste, with the aim of using the beneficial properties of waste or its components. In this case, the waste acts as a secondary raw material.

According to the state of aggregation, wastes are divided into solid and liquid; according to the source of formation - industrial, formed during the production process (metal scrap, shavings, plastics, ash, etc.), biological, formed in agriculture (poultry droppings, animal husbandry and crop waste, etc.), household (in particular , sewage sludge), radioactive. In addition, waste is divided into combustible and non-combustible, compressible and non-compressible.

When collecting, waste should be separated according to the criteria indicated above, and depending on the further use, method of processing, disposal, disposal. After collection, the waste is recycled, recycled and disposed of. Waste that can be useful is recycled. Waste recycling is the most important step in ensuring life safety, contributing to the protection of the environment from pollution and conserving natural resources.

The recycling of materials solves a whole range of environmental issues. For example, the use of waste paper makes it possible to save 4.5 m 3 of wood, 200 m 3 of water in the production of 1 ton of paper and cardboard and reduce energy costs by 2 times. It takes 15-16 mature trees to make the same amount of paper. The use of waste from non-ferrous metals gives a great economic benefit. To obtain 1 ton of copper from ore, it is necessary to extract from the depths and process 700-800 tons of ore-bearing rocks.

Waste plastics naturally decompose slowly or not at all.

When they are burned, the atmosphere is polluted with toxic substances. The most effective ways to prevent environmental pollution with plastic waste are their secondary processing (recycling) and the development of biodegradable polymeric materials. Currently, only a small part of the 80 million tons of plastics produced annually in the world is recycled.

Meanwhile, 860 kg of new products are obtained from 1 ton of polyethylene waste. 1 ton of used polymers saves 5 tons of oil.

The thermal processing of waste (pyrolysis, plasmolysis, incineration) with the subsequent use of heat has become widespread. Waste incineration plants should be equipped with highly efficient dust and gas cleaning systems, as there are problems with the formation of gaseous toxic emissions.

Waste that cannot be processed and further used as secondary resources is disposed of at landfills. Landfills should be located away from water protection zones and have sanitary protection zones. In places of storage, waterproofing is carried out to prevent contamination of groundwater.

For the processing of municipal solid waste, biotechnological methods are widely used: aerobic composting, anaerobic composting or anaerobic fermentation, vermicomposting.

Anthropogenic pollution of the environment of Sevastopol

Not only the issues of air and hydrosphere pollution are the number 1 issues in the city of Sevastopol. Often in newspapers, especially in "Glory of Sevastopol", you can read the headlines "A balcony" with a view "... on the trash", "We drowned in household waste ...

The impact of motor transport on the state of the environment

The impact of vehicles on humans and the environment

Substances that enter the atmospheric air with exhaust gases, and then settle on the soil. Soils have the ability to hold and store both atmospheric and groundwater...

Impact of high-speed rail transport on the environment

For wheeled rolling stock, a traditional rail track is used, in which, as a rule, a reinforced track grating is laid, and a special track structure is created for a levitating VSNT. With contact VSNT, laying the path ...

Global environmental problems of our time

The lithosphere is called the solid shell of the Earth. The lithosphere is polluted by liquid and solid pollutants and wastes. It has been established that every year one ton of waste is generated per inhabitant of the Earth ...

Legislative and other legal acts on environmental protection. Means of protection of the lithosphere

The following main areas can be distinguished: 1. Soil protection. 2. Protection and rational use of subsoil: the most complete extraction of the main and associated minerals from the subsoil; complex use of mineral raw materials...

Earth's magnetosphere, its structure. A set of measures to reduce noise. Methods of protection by distance, time from the impact of EMP on biological objects

It is known that electromagnetic radiation (EMR) from computers, other consumer electronics, cell phones is detrimental to human health. Many people naively think...

Air purification methods using a mist eliminator

Subsoil protection. Subsoil pollution and their irrational use negatively affects the state and quality of surface and groundwater, atmosphere, soil, vegetation, and so on. It becomes obvious...

Environmental problems of the modern world

Tackling the problem of air pollution requires concerted action at many different levels. Various documents are adopted at the level of governments and international organizations...

Ecological state of the Black Sea region

Coastal erosion, including coastal erosion, landslides, etc., which can cause significant economic damage, is typical mainly for the western and northern coasts of the Black Sea. As a possible cause of land erosion...

Ecological monitoring should be understood as organized monitoring of the natural environment, in which, firstly, a constant assessment of the environmental conditions of the human habitat and biological objects (plants ...

Ecology and environmental monitoring

To begin with, we highlight the main types of non-ionizing radiation in table No. 3. Table 3 Types of non-ionizing radiation Sources of exposure and nature of the technological process Characteristics of the impact Electrostatic fields Types ...

To protect soils, forest lands, surface and ground waters from solid and liquid wastes, the collection and storage of industrial and domestic wastes is currently widely used. Landfills and landfills for the processing and disposal of industrial waste have become negative companions of large industrial cities.

The landfills accept: arsenic containing inorganic solid waste and sludge; waste containing lead, zinc, tin, cadmium, nickel, antimony, bismuth, cobalt and their chemical compounds, galvanic production waste; organic solvents; organically combustible (cleaning materials, rags, resins, plastic scraps, etc.), oil products (waste), radioactive waste. The landfill should include a plant for the incineration of organic and disposal of toxic waste. Landfills must have the necessary sanitary protection zones.

The norm of chemical contamination of soils is set according to the maximum permissible concentrations (MPC) for water, air and soil.

A radical solution to the problem of protecting the lithosphere from industrial waste is the widespread use of waste-free and low-waste technologies and industries.

An example of recycling waste from the woodworking industry for the production of building materials is:

production of arbolite;

· production of slag-sawdust blocks;

· production of building wall blocks from burnt earth, cement and sawdust.

34. Fundamentals of placement, design and reclamation of municipal solid waste (MSW) landfills. Currently, the facility (landfill, landfill, etc.) for storage and disposal of waste is a complex engineering complex that ensures the safety of the functioning of industrial and residential areas.

The selection and justification of a site for the placement of a landfill for storage and processing of waste is the most important stage of design work. Landfills are located outside cities and other settlements, while sanitary requirements for placement must be observed.

The most favorable sites for landfills for the disposal of solid waste are considered to be exhausted quarries, ravines with the provision of protective measures.

When designing solid waste disposal facilities, it is necessary to analyze possible hazard scenarios:

during operation;

In the process of accumulation

long-term, not foreseen in the design.

All sanitary landfills are divided into the following types:

MSW landfills;

· landfills for hazardous waste;

landfills for construction waste;

landfills for industrial waste.

When designing landfills, the following criteria should be taken into account:

protection of groundwater;

filtrate management;

protection of surface waters;

landfill gas control;

· exploitation;

Efficient use of space

stability of slopes and slopes of the array.

Particular attention in the project should be paid to the design of the underlying screen, leachate collection system, landfill gas collection system; surface coating; monitoring, stormwater management, support services.

When designing landfills, the following measures for the rehabilitation of the territory should be provided, which should include:

landfill closure technology;

Landscape solutions

active use of the territory by the population;

cultural and historical significance.

35. Describe the essence of the technological design of TGV (TGVS) systems. Composition and purpose of POS and PPR. The peculiarities of heat and gas ventilation systems are that they include devices that operate under pressure above atmospheric and are located at a height or laid in various soil environments at the intersection with other engineering communications. At the same time, when laying gas pipelines, installing gas control systems and maintaining them, one has to deal with gas-air explosive atmospheres.

All these features impose an increased responsibility in terms of safety on workers and engineers, who must be prepared to work safely in conditions of increased danger.

One of the most important issues for ensuring safety during the construction of DHWs is the correct organizational and technical preparation.

Construction organization projects are carried out by a specialized design organization on the instructions of the customer, and PPR - by the contractor or general contractor.

In the PPR, safety issues are developed in detail, where all safety measures are justified by engineering calculations based on norms and rules.

Safety issues should be included in the flow charts for installation and other work during the installation of DHW. Technological maps must be drawn up for complex and dangerous work, as well as for work performed by new methods.

36. Describe the features of excavation and work at height. Definition of permanent hazardous areas for these types of work. One of the most important issues for ensuring safety during the construction of DHWs is the correct organizational and technical preparation.

This preparation includes two stages: organizational and technical.

At the stage of organizational preparation, a construction organization project (POS) is developed, and at the technical stage, a project for the production of works (PPR).

The radius of the danger zone during the operation of the jib crane, taking into account the departure of the load when the lines break, is:

Where r is the maximum reach of the boom, m;

s – possible departure of cargo, m;

h is the height of a possible fall, m;

l is the length of the sling branch, m;

α is the angle between the vertical and the branch;

a is the distance from the outer edge of the load to its center of gravity, m.

Particular attention in the production of earthworks should be paid to the resistance to collapse of loose slopes. So, the angle of repose ( φ ) for dry sand 25 ... 30º, wet sand - 20º, dry clay - 45º and wet clay - 15º. The safety of excavation and work inside it depends on the correct choice of slope angle.

Based on the stability of soils, the critical height of a vertical wall without slopes is determined by the formula

H cr = 2C cos φ / ,

where H cr is the critical height of the vertical wall;

C - soil cohesion, t / m 2;

is the soil density (φ is the angle of internal friction, which is determined according to the rules of soil mechanics).

37. Means of ensuring safety in the production of earthworks.

At the stage of organizational preparation, a construction organization project (POS) is developed, and at the technical stage, a project for the production of works (PPR).

Particular attention in the development of PPR should be paid to the safety of earthworks. This is due to the fact that earthworks in the construction of heating systems and gas pipelines are one of the main ones.

Earthworks can only be started if there is a PPR with the coordination of pipeline laying routes with the relevant organizations.

When constructing the vertical walls of pits and trenches in soft soils, it is necessary to provide for their fastening.

The fastening system is calculated on the active pressure of the soil. In fastenings of the spacer type, fastening boards, racks and spacers are subject to calculation. Struts are calculated for strength and stability according to the rules of structural mechanics.

When installing ventilation systems and when laying external pipelines and during other installation work, scaffolding and scaffolding are used. Most often, for installation work, scaffolding is used on boltless joints, where tubes are welded to the posts, and round steel hooks bent at a right angle to the crossbars. With this method of fastening, the installation of each horizontal element of the scaffolding is reduced to the introduction of hooks into the corresponding tubes on the racks until it stops.

Most often, during the construction of DHW, mobile collapsible scaffolds are used (GOST 28012 - 89). Due to some features, these scaffolds are used only indoors in the presence of a hard floor covering. In many cases, when laying communications along the walls, hinged scaffolds are used.

38. Means of ensuring safety when working at height during the construction and repair of TGVS One of the most important issues for ensuring safety during the construction of DHWs is the correct organizational and technical preparation. This preparation includes two stages: organizational and technical.

At the stage of organizational preparation, a construction organization project (POS) is developed, and at the technical stage, a project for the production of works (PPR).

Particular attention in the WEP should be paid to the definition and limitation of permanent hazardous areas. These zones include dangerous zones during the operation of tower and jib cranes, during the installation of ventilation and gas supply systems located at a height. This is due to the possibility of breaking the mounting slings and flying off the load to the side when it falls.

When working at height, an open area located under the work area is considered dangerous, the boundaries of which are determined by the horizontal projection of the work area increased by a safe distance p = 0.3 H, where P is the distance of the axis of the horizontal projection boundary, in meters , and H is the height at which the DHW installation is performed.

Most often, during the construction of DHW, mobile collapsible scaffolds are used (GOST 28012 - 89). Hanging scaffolds are designed to work at heights. These include hinged cradles, GOST 27372 - 87.

Scaffolds on telescopic towers are used both for indoor work at height and for outdoor installation work, GOST 28347 - 89.

When working on telescopic towers, installers are equipped with safety belts, which are attached to a steel safety rope using safety catchers.

39. Describe the basic safety requirements when working with a manual electrified device. In the construction and repair of DHWS in many cases, small-scale mechanization tools are used. These include: mechanized tools - a drilling machine, electric saws, electric shears, pneumatic hammers, grinders and sharpeners, mobile compressors, riveting devices.

The main safety requirements for the operation of hand-held electrified tools are:

exclusion of the possibility of mechanical injury;

· electrical safety;

· noise safety;

vibration safety.

The measures that ensure safety when working with a hand-held electrified tool are set out in the tool passports and safety instructions drawn up on the basis of SNiP 12 - 03 - 2001 “Labor safety in construction. Part 2. Construction production»

40. Name the main causes of electrical injuries during the construction and repair of DHW. And on what factors does it depend.Injury statistics show that the number of injuries caused by the action of electric current is low - 1 ... 2% of the total, however, fatal accidents are the largest. At the same time, 80% of them fall on electrical installations with voltages up to 1000 V.

The causes of electrical injury (electric shock to the human body) are:

intentional work under stress;

erroneous exposure to voltage;

Convergence or whipping of wires;

malfunction of electrical equipment;

Violation of the security zone of high-voltage lines and transportation of oversized cargo;

absence or irregularity of instruction;

Lack of protective equipment

Illegal combination of professions.

The external manifestation of electrical injuries are:

metallization of the skin surface on the human body.

The danger of current exposure to a person depends on such factors:

the magnitude of the current (the main factor);

the duration of the current;

the path of current in the human body;

type and frequency of current;

individual qualities of a person.

The most dangerous is alternating current with a frequency of 50 ... 500 Hz. A person can independently free himself from the action of an alternating current of 10 ... 15 mA, and with a direct current - 20 ... 25 mA. A current with a voltage of 12 ... 36 V is considered relatively safe for humans.

41. Specify the measures to eliminate the dangers of electric shock to a person. Injury statistics show that the number of injuries caused by the action of electric current is low - 1 ... 2% of the total number, however, fatal accidents are the largest. At the same time, 80% of them fall on electrical installations with voltages up to 1000 V.

using organizational and technical measures.

42. Ways and methods of ensuring safety in electrical installations. Particular attention in ensuring electrical safety at the construction site should be paid when working with temporary electrical wiring, which must be carried out with an insulated electrical wire and suspended on a cable on strong supports at a height of at least 2.5 m above the workplace, 3.5 m above the aisles and 6.0 m above the driveways. Portable lamps at the construction site are powered by a voltage of no higher than 42 V, and in damp areas, boilers, wells, metal tanks, etc. - no higher than 12 V.

To eliminate the danger of electric shock to a person when faulty and poorly insulated current-carrying parts of electrical equipment are connected to the ground, protective grounding is used.

The essence of protective grounding is to reduce the voltage on the electrical equipment case when a current is shorted to it.

In three-phase networks with a grounded neutral with a voltage of up to 1000 V, protective zeroing is arranged. It should be noted that it does not provide reliable protection.

If it is impossible to ground the equipment (frozen, rocky soils), in addition to protective grounding, a protective shutdown is used, the essence of which is to quickly automatically turn off the damaged section of the electrical network during a single-phase short circuit of current-carrying parts to the housing.

The electrical safety of electrical installations can be ensured in several ways:

designing safe and reliable electrical installations;

Providing protection by technical means;