RU2412014C1 - Method of purification and reclamation of ecological functions of substrates contaminated by oil and its products - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to biotechnology, namely, to methods of removing oil contaminants from substrates. Proposed method comprises processing the substrate by biopreparation and earthworms of native species. To prepare nutritive medium for earthworms, used is organic material crushed to 20-50 mm-particle size, i.e. leaf litter, sunflower shells and the like to be treated by lactoserum, its content making 40-80 l per one ton of organic material. Prepared material is added into substrate, apart from sandy soil, along with scarifier in amount sufficient for oxygen content in substrate not less than 12%. Then, nutritive medium is added into substrate in amount of 10-30% of total weight and, then, biofertiliser in amount of 70-90 ml per 1 m² of substrate. Ploughing is made to depth of 0.1-0.4 m.

EFFECT: higher efficiency of reclamation.

6 cl, 4 dwg

Description

The invention relates to the field of biotechnology, and in particular to methods for cleaning substrates from oil pollution, and can be used to eliminate the consequences of accidental spills of oil and oil products in rail, pipeline and road transport, as well as to improve the environmental situation around sources of hydrocarbon pollution (gas stations, reservoir parks, tank farms, boreholes, roadside areas).

Analysis of the current level of technology has allowed to identify the following analogues:

- known methods of microbiological cleaning of the soil with the help of microorganisms capable of destroying petroleum hydrocarbons, including preliminary mechanical processing of the soil, the application of organic and inorganic fertilizers and hydrocarbon-oxidizing microflora (see RF patent No. 2245748 dated 05/14/2002 according to IPC ⁷ В09С 1/08, publ. 02.10.2005; patent of the Russian Federation No. 2076150 dated 02.15.93 for IPC ⁶ C12N 1/20, publ. 03/27/1997; patent of the Russian Federation No. 2071671 dated 09/23/1994 for IPC ⁶ B09C 1/00, publ. 10.01.1997; patent RF patent No. 2049739 dated 09/19/1991 according to IPC ⁶ C02F 3/34, publ. 12/10/1995; RF patent No. 2062669 dated 01/10/1993 according to IPC ⁶ В09С 1/10, publ. 06/27/1996).

The disadvantage of this method is the reduced efficiency of the process of cleaning and restoring the environmental functions of the substrates. This is due to the fact that only hydrocarbons located on the surface of the substrate will be available for biological destruction, while hydrocarbons that penetrate deep into the substrate can be destroyed only due to the activity of anaerobic microflora. Therefore, the effectiveness of aerobic microorganisms that are part of the bacterial preparations will be low. In addition, increasing the productivity of substrates is achieved only by reducing the concentration of oil hydrocarbons, without fertilizing;

- there is a known method for the disposal of hydrocarbon-containing waste with an oil fraction, according to which a vermicultural composition of the following composition is proposed: linear kerosene, oil-contaminated solid drilling waste, hydrocarbon-oxidizing bacteria, soil and worms (see U.S. Patent No. 6838082 of 02/14/2002 for IPC C05F 17 / 00, published on January 14, 2005). An environmentally friendly drilling fluid is also proposed, which uses organic waste as a solid phase: rice husks, sawdust, shavings, cut paper, cardboard, coconut shavings, cotton husks, etc. At the same time, drilling waste material is populated with red earthworms (Lumdricidus rubellus, Eisenia foetida) grown using kitchen, agricultural waste and sewage sludge with a humidity of about 75%.

The disadvantage of this method is the reduced efficiency of the process of cleaning and restoring the environmental functions of the substrates. This is due to the fact that the nutrient medium is not optimal for cultivating earthworms, the claimed technical solution does not provide for the rehabilitation of oil-contaminated substrates. In addition, the method provides for the treatment of contaminated substrate in the reactor, which significantly increases the cost of disposal of oil-contaminated substrate, there is a need to control the oxygen content and additional aeration using an aeration device, since earthworms inefficiently perform aeration in adverse conditions;

- as a prototype, we took a method for cleaning and recultivating soils contaminated with oil and oil products, including soil treatment with preparations containing oil refining bacteria together with biodestructors of the next trophic level - earthworms. The bacterial preparation Putidul is used (see RF patent No. 2217246 of 03/18/1999 g according to IPC ⁷ B09C 1/10, publ. 11/27/2003).

The disadvantage of this method is the reduced efficiency of the process of cleaning and restoring the environmental functions of the substrates. This is due to the fact that in the known method, the reclamation of soils contaminated with oil products is achieved only due to the vital activity of earthworms, without the introduction of organic or inorganic fertilizers. In this case, the reclamation efficiency will be lower in comparison with the above methods involving the introduction of appropriate additives. In addition, the prototype method does not provide for the processing of the substrate: plowing, mixing or applying baking powder. In this case, only hydrocarbons located on the surface of the substrate will be available for biological destruction, and hydrocarbons that penetrate deep into the substrate can be destroyed only due to the activity of anaerobic microflora. Consequently, the effectiveness of aerobic microorganisms that are part of the bacterial preparations intended for the destruction of oil hydrocarbons will be low.

It should be noted that the Example does not indicate how many earthworms and what type the authors used for the experiment. Based on the data they cited, the initial concentration of oil and oil products in the soil was more than 21 g / kg. According to literature data, confirmed by our own studies, the limiting lethal concentration of oil and oil products in the soil, at which 100% of individuals die during the day, is 20 g / kg for the soil. At an initial oil concentration of 12 g / kg in the substrate, 50% of individuals die within 24 hours if the substrate has not been pretreated. (Soromotin A.V. Effect of oil pollution on soil invertebrates (mesofauna) in the taiga forests of the Middle Ob region // Siberian Journal of Ecology. - 1995. - No. 6. - P.549-552; A.G. Kartashev, K.S. Kozlov, A.G. Gryaznov, Effect of oil pollution on the survival of earthworms // Siberian Journal of Ecology, 2006, No. 5, t.13, p.629-637; Spirov A.V., Pushnoy G.V. test objects in screening systems for teratogens of the environment // All conference Ecological and genetic monitoring of the state of the environment. - Karaganda, 1990. - P.112; Kibardin V.M., Stallion in A.K., Effect of oil pollution on earthworms, Mater. 6 scientific conference of the mol. scientists Kazan, Institute of Biology, Kazan, Fil. of the USSR Academy of Sciences, Kazan, April 5-8, 1988. Kazan. -T Biol. Kazan. Fil. Academy of Sciences of the USSR. Kazan, 1990, pp. 230-232, ill.). In addition, the Example considers the use of the method in laboratory conditions in microvolumes - the layer of oil-contaminated soil was 50 mm (5 cm), and the total height of the cage was 60 mm (6 cm). Earthworms live in a substrate layer 10-70 cm thick, and if the substrate is toxic to the worms, they do not bury it, crawl along the surface and try to crawl out of the tank. With such small volumes of laboratory cages for the experiment, it is extremely difficult to keep the worms inside the substrate containing a lethal concentration of pollutant. From the description of the experiment it is not clear what means were used to detain earthworms in laboratory containers. Thus, the conditions for the industrial use of the prototype are not developed.

The technical result from the application of the claimed method is as follows:

the efficiency of restoring the environmental functions of oil-contaminated substrates increases in the temperature range of the substrate from +5 to + 45 ° C, with an initial oil and oil product content of not more than 20,000 mg / kg, while:

a) the destruction of oil pollution by indigenous hydrocarbon-oxidizing microflora is activated by creating optimal conditions for its life, as well as due to the lack of competition between introduced and indigenous microflora;

b) the living conditions of earthworms are improved, their vital activity is intensified: bioproductivity, increase in specific gravity;

c) increased substrate fertility due to enrichment with nutrients.

The specified technical result is achieved by processing the substrates with biological products and earthworms, that is, as indicated in the prototype.

We offer:

- additionally prepare a nutrient medium for earthworms. Grind organic material to a particle size of 20-50 mm and treat it with whey in a ratio of components: 40-80 l of the latter: 1 t of organic material;

- additionally process the substrate. At the same time, make: baking powder, nutrient medium, biological product. In all substrates, except for sandy soil, a baking powder is added in an amount providing an oxygen content of at least 12%. Cooked nutrient medium in an amount of 10-30% by weight of the substrate. Biological product, which uses biofertilizer, restoring the fertility of the substrates, in the amount of 70-90 ml per 1 m ^{2 of} substrate;

- carry out plowing to a depth of 0.1-0.4 m;

- use native species as earthworms. In this case, the mass of the introduced wormsubstrate is determined by the formula:

m _hs = K · S · h · ρ · G / Z,

where m _hs - the mass of wormsubstrate, kg;

K is an empirical coefficient that takes into account the death of individuals of earthworms, depending on the type of substrate and nutrient medium, ranging from 1.1-1.4;

S is the area of the treated area, m ² ;

h is the depth of processing of the substrate, m;

ρ is the density of the substrate, kg / m ³ ;

G is the optimal number of earthworms per 1 kg of substrate, selected empirically depending on the type of substrate, the number of individuals / 1 kg of substrate;

Z is the initial specific number of individuals per 1 kg of wormsubstrate product, the number of individuals / 1 kg of wormsubstrate;

- in the south of Russia to use earthworms of the species Lumbricidus rubellus;

- as organic material, use leaf litter or husk of sunflower, or fruit cake, or sunflower pulp, unbroken, or tops of agricultural crops, or dried grass, or waste tomato, or waste cabbage, or grape marc;

- as a whey use cheese or curd, or casein;

- use river sand or sawdust of non-coniferous tree species as a baking powder.

- as a biological product restoring soil fertility, it is preferable to use Baikal EM-1.

Based on the foregoing, the claimed technical solution meets the condition of novelty.

The method can be used when the concentration of oil and oil products in the substrate is not more than 20,000 mg / kg Higher concentrations completely suppress the vital activity of introduced microflora and are detailed for earthworms. In earthworms, active necrosis of superficial tissues is observed, softening of the longitudinal muscles, they lose mobility and die within a day.

The method can be applied at a substrate temperature of not lower than + 5 ° C and not higher than + 45 ° C. At lower temperatures, earthworms and microorganisms are inactive, and at higher soil temperatures, the worms go into the deeper layers of the substrate, form a “public cocoon” and hibernate. In addition, elevated temperatures contribute to a change in the species composition of the microbial community and the use of the proposed methods does not bring the expected effect.

Once in the environment, oil inhibits the respiratory activity of substrates, causes an almost complete depression of flora and fauna, disrupts the relationship between individual groups of microorganisms, in addition, nitrogen fixation and nitrification processes are inhibited, the balance of soil enzymes is disturbed, and hard-to-oxidize products accumulate. The substrate is a nutrient medium for plants and microorganisms, a complex concept that includes, including all types of soils and sapropels. In the contaminated areas, high phytotoxicity of the soil is formed, which is explained by the excessive content of chloride, sulfate and sodium bicarbonate in it. The impact of oil and oil products on soil ecosystems leads to a decrease in the biological productivity of soil and phytomass of vegetation cover. For most agricultural plants, oil-contaminated soil is toxic. Oil pollution has a negative effect on the germination of plants immediately after sowing seeds in the ground. The inhibitory effect of oil on the most resistant plants is already observed at a pollution level of about 400-500 mg / kg. The growth of plants in the early stages is significantly behind the control in height.

According to the claimed method, in contrast to the prototype, we do not use bacterial preparations intended for cleaning the soil from oil hydrocarbons. It is known that all natural substrates contain native hydrocarbon-oxidizing microflora. It consists of microbial populations of algae, actinomycetes, nitrifying, denitrifying, cellulose-degrading bacteria, sulfur bacteria, pigment microbes, fungi, protozoa. The largest number (1,000,000 in 1 mm ³ ) of microbes is contained in the upper soil layer - at a depth of 5-15 cm (see Guzev VS, Bondarenko NG, etc. The structure of the initiated microbial community as an integral method for assessing the microbial state of the soil // Microbiology. - 1980. - 49, No. 1. - P.134-139; Guzev BC, Levin SV, et al. The role of soil microbiota in the rehabilitation of oil-contaminated soils // Microorganisms and soil protection. - M.: Moscow State University, 1989. - P.129-150; Zvyagintsev DG et al. Diagnostic signs of various levels of soil pollution with oil, Soil Science, 1989, No. 1, - P.72-78.).

Our proposed method for cleaning and restoring the environmental functions of oil-contaminated substrates is based on creating favorable conditions for the oxidation of oil hydrocarbons by native hydrocarbon-oxidizing microflora. The method is applicable to the following types of substrates: sapropel (deposits of freshwater bodies of water, consisting of organic matter and mineral impurities, formed as a result of long natural processes from the remains of plant and animal organisms inhabiting the body of water), chernozems, loams, gray forest, chestnut (light, dark saline) and sandy soils.

Oil leads to a violation of the structure of the substrates, namely, it leads to the adhesion of particles into a single conglomerate, the formation of a gas-tight film. As a result, many biological processes slow down or stop. Most microorganisms that can destroy oil hydrocarbons are aerobic. They are the main suppliers of plant nutrients, and oxygen is essential for vital processes.

Thus, the organization of aeration of the substrate and the restoration of its structure (separation into individual particles) becomes a leading problem. This function is effectively performed by earthworms, moving in the ground, passing it through their digestive system, providing aeration, soil structure, distribution of organic material along the soil horizon, the presence of a number of biologically active substances (enzymes, vitamins, growth factors). There are certain requirements for worms. They should have high voracity, mobility, provide a high degree of decomposition of organic substrates, be resistant to diseases and physico-chemical influences, and a high rate of adaptation to processed substrates. In the USA, a productive selection of the Eisenia foetida worm, called the "California Red Worm," obtained by selection, is used for cultivation. In Europe, it is known under the trade name "Tennessee Wigler." However, this worm, despite its undeniable advantages, is poorly adapted to the climatic conditions and soils of Russia. In our country, an earthworm hybrid was bred, not inferior in its main productive properties to the American counterpart, adapted to the natural and climatic conditions of the middle lane. Bred in the Vladimir region, the hybrid was named the Prospector. The transportation of earthworms over considerable distances is associated with additional death of some individuals in the population and the deterioration of the general condition of survivors, in addition, the worms are forced to adapt to new climatic conditions, a change in feed is inevitable, which is an extremely traumatic factor. In this regard, the most appropriate is the use of native species of earthworms adapted to oil pollution and local climatic conditions. For the South of Russia it is recommended to use Lumdricus rubellus earthworms that have passed adaptation to oil pollution of substrates.

Earthworms improve the living conditions of microorganisms and are a factor that ensures the growth of the number of hydrocarbon-oxidizing microflora and intensifies the destruction of oil pollution. According to the Methodology for determining the damage to the environment during accidents at the main oil pipelines (Guidance document "Methodology for determining the damage to the environment during accidents at the main oil pipelines" / approved by the Ministry of Fuel and Energy of the Russian Federation on 01.11.95 - M., 1996. - 68 p. RD) the low level of contamination of the substrate with oil and oil products is considered to be the content of oil hydrocarbons from 1000 to 2000 mg / kg Therefore, as a technical result of the application of the proposed technology, it is necessary to achieve an oil hydrocarbon content in the substrate of more than 1000-2000 mg / kg as soon as possible.

A nutrient medium is prepared to provide earthworms with a sufficient amount of oil-free feed. Preparation of a nutrient medium using whey significantly reduces the percentage of deaths of the population (from 5 to 30%).

To prepare a nutrient medium for earthworms, the available organic material must be crushed to particles ranging in size from 20 to 50 mm. For larger particles of organic material, larger than 50 mm, the duration of pre-treatment with milk serum increases noticeably, upon receipt of smaller particles, less than 20 mm, the bulk density of the substrate increases, its aeration worsens. The introduction of whey containing lactic acid microflora prevents the decay of organic material, translating them into fermentation processes. The use of whey as a sourdough allows you to suppress the development of molds and yeasts, abundantly developing in the upper layer of fermented organic material, its quality as a breeding ground for earthworms is improved. The introduction of whey is made at the rate of 40-80 liters per 1 ton of organic material. When using less serum, that is, less than 40 l / t, rotting processes will not be completely suppressed, the required number of lactic microflora will not be achieved; when making large volumes of whey, that is, more than 80 l / t, the moisture content of the organic material will be excessive.

In the proposed method for cleaning and restoring the environmental functions of oil-contaminated substrates, a baking powder is introduced into the substrate. When substrates are contaminated with oil and petroleum products, gas exchange processes with the environment are disrupted in them, their hydrophobic properties are enhanced, increased caking, the formation of solid, dense, poorly degradable agglomerates (cutans) are observed. Sawdust of conifers is not used, since the high content of resinous substances adversely affects the life of earthworms. A decrease in the oxygen content in the substrate below 12% negatively affects the development of aerobic microorganisms and plants. The preferred baking powder for use in the proposed method is river sand.

The introduction of a nutrient medium for earthworms enriches the substrate with organic material. The introduction into the substrate of a nutrient medium in an amount of less than 10 wt.% Will not be able to provide a sufficient amount of fodder uncontaminated with hydrocarbons for earthworms. The introduction of a substrate of a nutrient medium of more than 30 wt.% Will significantly increase the cost of the cleaning of the substrate without noticeable intensification of the destruction of oil hydrocarbons in the substrate.

The method involves processing the substrate with a biological product, which is a biological fertilizer that restores the fertility of the substrates. The preferred biological product is Baikal-EM-1 biological fertilizer. The biological product contains a large number of anabiotic (beneficial) microorganisms living in the soil: lactic acid, nitrogen-fixing, nitrifying bacteria, actinomycetes, yeast and fermenting fungi. Interacting in the soil, they produce enzymes and physiologically active substances, amino acids, nucleic acids, which have both direct and indirect positive effects on plant growth and development. Between the microflora of the biological product and earthworms, symbiotic relationships are established that increase the tolerance of earthworms to oil pollution, and the survival rate of earthworms is increased by 4-6%. The introduction of a biological product in the substrate in an amount of less than 70 ml / m ² will not provide the optimal number of microflora in the treated area, exceeding the claimed dosage of the biological product increases the cost of cleaning the substrate from hydrocarbon contamination, while the destruction efficiency of petroleum hydrocarbons does not increase.

Microorganisms in the soil form a complex biocenosis in which their various groups are in a complex relationship. Some of them successfully coexist, while others are antagonists (opponents). Their antagonism is usually manifested in the fact that some groups of microorganisms inhibit the development of others. Therefore, the introduction of microbiological preparations into substrates does not always give the expected result. Introduced microflora can enter into competition with native substrate microflora. As a result, there is a decrease in the number of target groups of microorganisms and the intensity of their vital processes, and substrate productivity is deteriorating.

Biological product "Baikal-EM-1" contains a microbiological composition consisting of microorganisms characteristic of substrates with high bio-productivity. When using this biofertilizer, there are no problems with the compatibility of indigenous and introduced microflora. The biological product "Baikal-EM-1" includes lactic acid bacteria contained in a nutrient medium for earthworms, as well as actinomycetes and fermenting fungi. Lactic acid bacteria produce lactic acid, suppressing the development of putrefactive and pathogenic microflora, improve the sanitary condition of the treated area. Lactic acid bacteria contribute to the decomposition of lignins and cellulose and ferment these substances. Vital activity of actinomycete inhibits the growth of fungi. Fermenting fungi such as Aspergillus and Penicillium quickly decompose organic substances, including those involved in the destruction of petroleum hydrocarbons, and secrete antibiotics. Fermenting fungi suppress odors and prevent soil infection by harmful insects and their larvae, and prevent the development of the main earthworm parasites. Thus, the introduction of a biological product ensures the restoration of the fertility and environmental functions of oil-contaminated substrates.

In order to mix the added additives with a substrate contaminated with oil and oil products, plowing is carried out. Oil penetrates in most cases to a depth of 5-10 cm, and only in some cases, in case of major accidents in pipelines or oil wells, the power of the oil-contaminated layer can reach 40 cm. Therefore, it is sufficient to plow to a depth of 0.1 to 0.4 m depending on the initial contamination of the substrate with oil hydrocarbons and the depth of penetration of oil and oil products into the substrate.

Having studied the patent documentation and scientific and technical literature in this field, the authors came to the conclusion that it is not known the preparation of a nutrient medium for earthworms according to the claimed method, its introduction into the substrate in the claimed amounts, as well as the use of biofertilizer in the claimed amounts to restore fertility in order to reduce fertility the concentration of hydrocarbons in the substrate. At the same time, the authors recommend the use of native earthworms. The authors believe that the claimed technical solution has an inventive step.

Example 1. The cleaning and restoration of the environmental functions of soprapel contaminated with crude oil from the Stavropol fields. Prepare a growth medium. The leaf litter for laboratory experiments is crushed with a secateurs, and on an industrial scale - crushed in a 99-3 grade disintegration unit to a size of 20-50 mm, and laid in containers. The crushed leaf litter in the amount of 10 kg (1 t for industrial use) is treated with milk serum according to OST 49-92-75 in the amount of 0.4 l for cottage cheese, and for industrial use - 40 l of cottage cheese whey. Leave for fermentation and fermentation for 5 days.

Process the substrate. For laboratory conditions, 30 kg of sapropel (for industrial use - 100 m ² ) with an initial level of oil pollution of 6000 mg / kg contribute 1.5 kg (5%) of sand, which provides an oxygen content of at least 12% in the substrate. For industrial use, sapropel is processed using a sand spreader 13-1975-14, and the amount of sand is determined by the formula:

m _p = 0.01 · S · h · ρ · P,

where m _p - the required amount of sand, kg;

S is the area of the treated area, m ² ;

h is the depth of processing of the substrate, m;

ρ is the density of the substrate, kg / m ³ ;

L is the optimal amount of organic material in the substrate, wt.%.

P is the optimal amount of sand in the substrate

m _p = 0.01 · 100 · 0.1 · 880 · 5 = 440 kg.

Prepared nutrient medium is added to sapropel in an amount of 3 kg (10 wt.%), And for industrial use using a centrifugal fertilizer spreader AMAZONE ZA-X Perfect, the calculation is carried out according to the formula:

m _o = 0.01 · S · h · ρ · L,

where S is the area of the treated area, m ² ;

h is the depth of processing of the substrate, m;

ρ is the density of the substrate, kg / m ³ ;

L is the optimal amount of organic material in the substrate, wt.%.

m _o = 0.01 · 100 · 0.1 · 880 · 10 = 880 kg.

For laboratory conditions, the bacterial preparation "Baikal-EM-1" is added to sapropel in an amount of 150 ml, and for industrial conditions 70 ml of the bacterial preparation per 1 m ^{2 of} substrate, and for processing 100 m ² - 7 l.

In laboratory conditions, the substrate is thoroughly mixed, and for industrial use, plowing to a depth of 0.1 m is carried out using an MT3-80 tractor equipped with a mounted plow PLN-5-35.

In the treated sapropel, earthworms Lumdricus rubellus are introduced manually in the laboratory, 1260 ± 1 animals each (taking into account the coefficient taking into account the death of individuals), in industrial use, the mass of the wormsubstrate is determined by the formula:

m _h = 1.2 · 100 · 0.1 · 880 · _35/200 = 1848 kg.

Watering is carried out to an optimum humidity of 70-80%. The temperature of the substrate throughout the experiment is 19-21 ° C. After 30 days, the oil content in the contaminated sapropel was 2000 ± 100 mg / kg, and after 45 days, 1000 ± 100 mg / kg. Figure 1 presents a graph of the dependence of the decrease in the concentration of oil in sapropel from time to time, while the dashed curve indicates the decrease in the concentration of hydrocarbons of oil in the untreated substrate according to the claimed method, and the solid curve - according to the claimed method.

For comparison, in the control for sapropel without treatment by the present method, after 45 days, the oil content was 3800 ± 100 mg / kg

The survival rate of earthworms in sapropel treated by the present method was 89.1 ± 1.5%, while the survival rate in untreated sapropel was 42.5 ± 1.5%, the average weight of the surviving individuals was 47.5 mg, in an untreated substrate 1.6 mg, fecundity was 4.8 cocoons / individual, in untreated 1.4 cocoons / individual.

Figure 2 presents a diagram of the fertility of earthworms,

where 1 is the fertility of the worms in freshly contaminated sapropel,

2 - the fecundity of worms in contaminated sapropel without treatment by the present method,

3 - fertility of worms in uncontaminated sapropel,

4 - the fertility of the worms in the processed sapropel according to the claimed method.

Figure 3 presents the dependence of the increase in the average mass of earthworms on time, while the dashed line indicates the change in the average mass of the worms in the substrate untreated by the claimed method, and the solid curve - according to the claimed method.

Next, samples of the processed substrates were seeded with watercress. Watercress biomass on the treated sapropel was 114 ± 1% compared to an uncontaminated substrate.

Example 2. Cleaning and restoration of the ecological functions of weakly leached chernozem contaminated with crude oil of the Stavropol deposits with an initial concentration of 20,000 mg / kg for a plot of 100 m ² .

Prepare a nutrient medium as described in example 1, but as an organic material use the husk of sunflower, while the grinding operation is not carried out. Processed with whey, namely casein, in the amount of 60 liters per 1 ton of husk of sunflower.

The substrate is treated as described in example 1, but contribute (10%) of sand in an amount of 4 tons according to the calculation:

m _p = 0.01 · 100 · 0.4 · 1000 · 10 = 4000 kg.

Prepared nutrient medium contribute in the amount of 12 tons according to the calculation:

m _o = 0.01 · 100 · 0.4 · 1000 · 30 = 12000 kg.

Introduce 90 ml of the bacterial preparation "Baikal-EM-1" per 1 m ^{2 of} substrate, that is, 9 liters.

Plowing to a depth of 0.4 m.

Contribute to earthworms Lumdricidus rubellus in an amount determined by the formula:

m _h = 1.4 · 100 · 0.4 · 1000 · _40/200 = 11200 kg.

After 180 days, the oil content in the chernozem was 1800 ± 100 mg / kg, which corresponds to the condition for a low level of substrate pollution by oil and oil products specified in the RD. In the control for weakly leached chernozem without treatment by the present method after 180 days 13600 ± 100 mg / kg

The survival of earthworms in a slightly alkaline chernozem treated according to the present method was 54.1 ± 1.5%, while no surviving earthworms were found in untreated chernozem, the average weight of the surviving individuals was 104 mg, and the fertility was 1.8 cocoons / individual .

Further, samples of the substrates were seeded with watercress. Watercress biomass on treated slightly alkaline chernozem was 89 ± 1% compared to an unpolluted substrate, watercress biomass on untreated substrate was 11.8 ± 1%.

Example 3. Cleaning and restoration of the ecological functions of loams contaminated with crude oil from the Stavropol deposits with an initial concentration of 12 mg / kg for a plot of 100 m ² .

Preparing a nutrient medium as described in example 1, but as the organic material using waste cabbage. Processed with whey, namely cheese in the amount of 80 liters per 1 ton of waste.

The substrate is treated as described in example 1, but contribute (10%) of sand in an amount of 2.4 tons according to the calculation:

m _p = 0.01 · 100 · 0.2 · 1200 · 10 = 2400 kg.

Prepared nutrient medium contribute in the amount of 7.2 tons according to the calculation:

m _o = 0.01 · 100 · 0.2 · 1200 · 30 = 7200 kg.

Contribute 80 ml of the bacterial preparation "Baikal-EM-1" per 1 square. m of substrate, that is, 8 liters.

Plowing to a depth of 0.2 m.

Contribute to earthworms Lumdricidus rubellus in an amount determined by the formula:

m _h = 1.4 · 100 · 0.2 · 1200 · _35/200 = 5880 kg.

After 110 days, the oil content in the contaminated loam was 1400 ± 100 mg / kg. For comparison, in the control for loam without treatment according to the claimed method, after 110 days, the oil content was 8100 ± 100 mg / kg

The survival rate of earthworms in loams processed by the present method was 72.4 ± 1.5%, while the survival rate in the untreated substrate was 34.5 ± 1.5%, the average weight of the surviving individuals was 71.1 mg, in the untreated substrate 28.4 mg, fertility, respectively, amounted to 2.9 and 0.9 cocoons / individual.

Next, samples of the processed substrates were seeded with watercress. Watercress biomass on the treated loams was 119 ± 1% compared to an uncontaminated substrate.

Figure 4 presents a diagram of the biotesting of samples of substrates

where: 1 - biomass of watercress obtained on freshly contaminated loam,

2 - biomass of watercress obtained on loam without processing by the present method,

3 - biomass of watercress obtained on unpolluted loam,

4 - biomass of watercress obtained on loams processed according to the claimed method.

The claimed technical solution meets the condition of industrial applicability.

Claims (6)

1. The method of cleaning and restoring the environmental functions of substrates contaminated with oil and oil products, which consists in treating the substrate with biological products and earthworms, characterized in that they further prepare a nutrient medium for earthworms, while the organic material is crushed to particle sizes as necessary 20-50 mm, they are treated with milk whey in the ratio of components: 40-80 l of the latter: 1 t of organic material and then the substrate is further treated, with the following It can be added to all substrates except sandy soil, a baking powder in an amount providing an oxygen content of at least 12%, a prepared nutrient medium in an amount of 10-30% by weight of the substrate, a biological product, which is used as a biological fertilizer, restoring the fertility of the substrates, the amount of 70-90 ml per 1 m ^{2 of} substrate and plowing to a depth of 0.1-0.4 m, and native species are used as earthworms, while the mass of the introduced wormsubstrate is determined by the formula:
m _hs = K · S · h · ρ · G / Z,
where m _hs - the mass of wormsubstrate, kg;
K is an empirical coefficient that takes into account the death of individuals of earthworms, depending on the type of substrate and nutrient medium, ranging from 1.1-1.4;
S is the area of the treated area, m ² ;
h is the depth of processing of the substrate, m;
ρ is the density of the substrate, kg / m ³ ;
G is the optimal number of earthworms per 1 kg of substrate, selected empirically depending on the type of substrate, the number of individuals / 1 kg of substrate;
Z is the initial specific number of individuals per 1 kg of wormsubstrate product, the number of individuals / 1 kg of wormsubstrate. 2. The method according to claim 1, characterized in that in the south of Russia earthworms of the species Lumbricidus rubellus are used. 3. The method according to claim 1, characterized in that the organic material used is leaf litter, or sunflower husk, or fruit cake, or sunflower pulp, unbroken, or crop tops, or dried grass, or tomato waste, or cabbage waste, or grape marc. 4. The method according to claim 1, characterized in that as the whey use cheese, or cottage cheese, or casein. 5. The method according to claim 1, characterized in that as a baking powder use river sand or sawdust of non-coniferous tree species. 6. The method according to claim 1, characterized in that as a biological product, restoring soil fertility, mainly use "Baikal EM-1".

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