RU2431532C1 - Method of decontaminating soils polluted by oil and oil slimes - Google Patents

Abstract

FIELD: process engineering. ^ SUBSTANCE: invention relates to microbiological treatment of soils polluted by oil products, soil recultivation and may be used in oil extraction and processing industries. Proposed method comprises formation of separate working sites, soil sampling for oil content analysis. Results of analysis are fed into analyser for comparison with specified ratings. Thereafter, additional computer outputs personal recommendations on required amount of structure-forming agent, fertilisers and biological preparation for producing decontaminating layer on said working site. Fertilisers are applied in soil mass prepared on said site in the form of 0.07-0.1%-solution at the rate of 0.5-1 g/m2. Processed layer is periodically sampled for content of oil products on different sites. Results of analysis are used by computer to output quantitative recommendations on additional application of ingredients into layer or instruction for cleaning said working site for next portion of soil to be decontaminated. ^ EFFECT: efficient and ecologically safe process at minimum costs. ^ 4 cl, 1 dwg, 1 tbl, 3 ex

Description

The method for the disposal of oil-contaminated lands and oil sludge relates to the microbiological treatment of soils contaminated with oil products, and the processing of oil sludge and can be used, for example, in the oil and oil refining industry for the treatment of soil contaminated with oil products and land reclamation.

The well-known "Method of microbiological treatment of oil sludge and soil contaminated with oil products (options)" according to patent RU 2311237 dated 05/02/2006, published on 11.27.2007, IPC B09C 1/10, C12N 1/26.

A method comprising applying immobilized oil-oxidizing microorganisms immobilized onto a biomass carrier with mineral fertilizers, using the Ekolan sorbent as a biomass carrier, immobilizing biomass taken at a concentration of at least 10 g / l, performing incubation with the sorbent for at least 1 hour in a mineral solution fertilizers taken in an amount of 2-16 g / l, at a pH of not more than 7.0 in the presence of polyvalent aluminum cations introduced in an amount of up to 100 mg / l, microorganisms with n the highest hydrophobicity index of the cells and their colony morphotype is determined, if microorganisms have S- or M-type colonies, then they are used for immobilization on Ekolan, the sorbent with immobilized oil-oxidizing microorganisms is introduced into the treated soil or sludge in a ratio of 1: 1000 by weight, respectively mix regularly, maintaining humidity 60% of the maximum moisture capacity and applying mineral fertilizers; oil-oxidizing microorganisms are selected from the composition of the indigenous oil-oxidizing microflora of the cleaned object; oil-oxidizing microorganisms are selected from the collection of oil-oxidizing microorganisms; mineral fertilizers are introduced taking into account the needs of oil-oxidizing microorganisms in nutrients; aluminum cations are introduced at a concentration of 51.3 mg / l in the composition of the aluminum salt.

But to implement this method, a carrier is needed, which increases the cost of work, the volume of additional transportation, the cultivation of an indigenous culture on a carrier, requires additional time and labor.

Also known is the “Method for cleaning soil from contamination with oil and oil products” according to patent RU 2137559 dated 07/07/1998, published on 09/20/1999, IPC B09C 1/10, B09C 1/08, including the introduction of microorganisms and mineral additives containing nitrogen into the polluted environment and phosphorus, while peat is used as a source of microorganisms, which is pre-activated by the introduction of mineral additives containing nitrogen and phosphorus, followed by incubation in the mesophilic mode for 3-7 days.

But with this method, peat is used as a source of microorganisms, which is impossible to apply in all areas without additional delivery costs, additional significant time is required for incubation.

The closest in technical essence is the "Method of processing oil sludge" according to patent RU 2198747 dated 11/14/2000, published on 02/20/2003, IPC B09C 1/10, C12N 1/26, C12N 1/26, C12R 1:07, including mixing oil sludge with microorganisms and a biostimulator, while before mixing with microorganisms and a biostimulator, clean soil and sawdust are added to the oil sludge, while the bacterial strain Bacillus sp. VNIISKHM 132 in the form of the Bacispecin preparation obtained on its basis, and the Biotrin protein feed additive in a mass ratio of mixed oil sludge: Bacispecin preparation obtained on the basis of the bacterial strain Bacillus sp. VNIISKHM 132: protein feed additive "Biotrin" as 1: 0.005: 0.005 followed by an incubation period; mixed oil sludge is prepared in the ratio of oil sludge: soil: sawdust as 1: 2: 1; after an incubation period of at least 50 days, an additional treatment with Biotrin protein feed additive is carried out.

But with this method, the use of the Bacispecin preparation requires the use of exclusively Biotrin feed additives as a biostimulator, which significantly increases the cost of the reclamation process and stretches it in time.

The objective of the proposed technical solution is to develop a method for the disposal of oil-contaminated land and oil sludge, which makes it possible to rationally use the areas allotted for microbiological treatment, to carry out efficient and environmentally friendly treatment at different degrees of contamination at the same time, without the use of additional special equipment, with minimal labor and time for preparing the soil to be cleaned.

The problem is solved by the method of neutralizing oil-contaminated lands and oil sludge by mixing the soil to be cleaned with a structurer, for example sand or sawdust, fertilizer and a biodestructor, while, as individual work sites are formed, samples of the delivered soil are collected from each for the content of oil products, the results of which are through the recorder served in the analysis unit, which, after comparing with regulatory data, issues personal recommendations on the need for additional Qdim texturizers and amount of fertilizer and an amount necessary for the preparation of a biological product is to be cleansed layer at a given work site; fertilizers are applied to the soil mass prepared at the site in the form of a 0.07-0.1% solution at the rate of 0.5-1 g / m ² ; as a biodestructor, the Destroil biological product (Acinetjbacter sp. JN-2 bacterial strain) is used as a 0.06-0.1% suspension at the rate of 0.5-1.5 l / m ² ; prepare a suspension by pre-mixing the calculated amount of the drug with a small amount of water, followed by dilution in a 0.04-0.1% solution of nitrogen-phosphorus fertilizers, aerating for up to 6 hours with periodic, after 2-3 hours, vigorous stirring for 20-30 minutes; biological product "Destroyl" is applied to the cleaned layer by sprinkling, in the form of a suspension prepared in the ratio of 0.6-1.0 g of the drug per 1.0 liter of industrial water; based on the results of periodic sampling of the cleaned layer for the content of petroleum products from individual work areas, the calculation unit issues quantitative recommendations for the additional introduction of ingredients into the cleaned layer of each work area; carry it out on the site, divided into working areas with an embankment along the perimeter and having a waterproof layer at the base.

The formation of individual work sites and sampling from each of them, the results of which are fed through the recorder to the analysis unit, allows, after comparing with the normative data, to calculate in the additional calculation unit and give personal recommendations about the required amount of the builder and the required number of fertilizers and biological product, for the preparation of the layer to be cleaned at a given work site, which optimizes the process of biodegradation of oil products of each work site separately and provides separate reception workers map the site of oil-contaminated land and oil sludge with varying degrees of oil contamination and different times of reclamation, and as a result, savings of fertilizer, biological product, energy and labor costs.

Fertilizing at the initial stages of treatment in the soil mass prepared at the site, in the form of a 0.07-0.1% solution, at the rate of 0.5-1 g / m ² , allows microorganisms to provide biogenic elements and increase biomass.

The use of Destroil biological product (Acinetjbacter sp. JN-2 bacterial strain) as a biodestructor in the form of a 0.06-0.1% suspension at a rate of 0.5-1.5 l / m ² and suspension preparation by preliminary mixing the calculated amount of the drug with a small amount of water, followed by dilution in a 0.04-0.1% solution of nitrogen-phosphorus fertilizers, aeration up to 6 hours with periodic, after 2-3 hours, intensive stirring for 20-30 minutes leads to an economical consumption of the drug.

Application of the biological product "Destroyl" on the cleaned layer by sprinkling, in the form of a suspension prepared in the ratio of 0.6-1.0 g of the drug per 1.0 liter of industrial water, allows you to evenly apply the biological product on the surface of the treated soil, create favorable conditions for the growth of bacteria and biodegradation of petroleum products

Periodic sampling of the cleaned layer for the content of petroleum products from individual work sites allows you to determine the degree of purification from petroleum products and, if these data go beyond the limits acceptable for reclaimed land, give the calculation unit quantitative recommendations on the additional introduction of ingredients into the cleaned layer of each work site, this in turn, it leads to the prevention of under-treated soil getting out of the site, timely release of work areas from ready-to-use the use of soil, increasing the percentage of yield of reclaimed soil.

Carry out the proposed method of disposal of oil-contaminated land and oil sludge on the site, which is shown in the drawing, where Fig. 1 - site 1 for the disposal of oil-contaminated land and oil sludge, cleaned layer 2, embankment 3, the surrounding soil 4, work sections 5, water-resistant layer 6, registration unit 7, analysis unit 8, preparation preparation 9 and fertilizer solution capacity 9, regulatory data unit 10, calculation block 11 for issuing recommendations, plot 12 for preparing the structurer.

The method of disposal of oil-contaminated land and oil sludge is as follows.

To neutralize oil-contaminated lands and oil sludge at site 1, work areas 5 are prepared with a water-resistant embankment 3, a height of at least 0.6 m along the perimeter, with a water-resistant layer 6 at the base, to prevent the migration of dissolved oil products into the aquifers of the surrounding soil 4.

Oil-contaminated soils or oil sludges are delivered by any known method and discharged directly to work areas 5, they are leveled across the site with a layer of not more than 0.4 m. As work sites 5 are formed, samples of delivered soil are taken from each for the content of oil products, the results of which are fed through the recorder 7 into the analysis unit 8, which, after comparing with the regulatory data of the block 10, issues through the calculating block 11 recommendations to section 12 about the required number of structurers and capacity 9, about the required number ETS fertilizer and a biological product for the preparation of layer 2 is to be cleansed, to optimize the biodegradation process oil each working segment individually (see table).

Name of materials Consumption Conc. n / a in soil no more than 5% Conc. n / a in soil no more than 10% Conc. n / a in soil no more than 15% Conc. n / a in soil no more than 20% Conc. n / a in soil more than 20% Biological product "Destroyl" 3-5 kg / ha 4-6 kg / ha 9-12 kg / ha 10-15 kg / ha Bringing the concentration of n / a to a level of less than 20% by introducing structurators Nitrogen-phosphorus fertilizers * for activation of a biological product 3 kg / ha 4 kg / ha 5 kg / ha 6 kg / ha Structurers - - - - Depending on the amount of pollution 1 * Nitrogen-phosphorus fertilizers with a ratio of N ₂ : P ₂ O ₅ = 1: (1-2.5-5.0) (ammophos, ammophos, diammophos, azofoska).

Before mixing with a biodestructor, a structurator is added to the oil sludge or oil-contaminated soil in the form of clean soil, or sand, or vegetable waste, or sawdust.

The drug Destroyl (a bacterial strain Acinetjbacter sp. JN-2) is used as a biodestructor.

To provide microorganisms with biogenic elements and build up biomass, at the initial stages of purification by the claimed preparation, ammophos, diammophoska or nitroammofoska fertilizers are used. Fertilizers are applied to the prepared soil mass in the form of a 0.07-0.1% solution at the rate of 0.5-1 g / m ² .

The application of the biological product "Destroyl" on the cleaned layer 5 is carried out in the form of 0.06-0.1% suspension at the rate of 0.5-1.5 l / m ² .

To prepare the working suspension, the calculated amount of the drug is stirred in a small amount of water, and then poured into a container 9 with a solution of the dilution medium, in the form of a 0.04-0.1% solution of nitrogen-phosphorus fertilizers. After making the entire required amount of the biological product, the suspension is periodically, after 2-3 hours, activated, intensively mixed for 20-30 minutes to ensure aeration. The total aeration time of the biological product is up to 6 hours.

The suspension is carried out by sprinkling in any known manner.

From the cleaned layer of 2 work sites 5, periodic sampling of the cleaned layer for the content of oil products from individual work sites is carried out, as a result of which the calculation unit 11 gives quantitative recommendations on the additional introduction of ingredients into the cleaned layer of each work site or a command to release this work site for the next batch the cleared soil.

Depending on the results of the analysis and weather conditions, the cleaned layer 2 is moistened up to 60-70% and loosened to create good aeration conditions for microorganisms.

After the neutralization process is completed, the work sites 5 are freed from the cleared soil by moving it to dumps, followed by loading onto vehicles and transported for further use - for sanitary dumping of solid waste landfills, dumping of roads and lodges, embankment of bush sites, backfill of quarries, elimination of ravines, land improvement and other construction works, as well as as a structural engineer when performing work on the disposal of oil sludge.

Example 1. In May 2008, on one of the working maps of the experimental production site No. 2 - 1.7 hectares with a clay screen - 4250 tons of oily waste from earth pits of Russian Railways and 4250 tons of sand were placed, after the mixture was distributed over the site, soil sampling to determine the content of petroleum products. The average concentration was 121.4 mg / kg. The soil was moistened to 60%, fertilizers (azofoska) were added in the form of a 0.03% solution. By sprinkling, 10.2 kg of Destroil biological product was added as a 0.1% suspension. The soil to be cleaned was regularly moistened, loosened, and a fertilizer solution was applied once every 2 weeks, and soil samples were periodically taken to determine the oil content. After 1.5 months, according to the results of the analysis of the samples, the cleaned layer was re-treated with a biological product similar to the first treatment. The remaining 4.5 months was only watering and mineral fertilizing. In November 2008, soil samples were taken to determine the residual oil content. The average concentration of petroleum products was 14.7 mg / kg, the cleaning efficiency was 87.9%, after which the work card was released for the next portion of the treated soil

Example 2. In May 2009, on one of the working maps of the experimental production site No. 4 - 2 hectares with a clay screen - 5,000 tons of soil contaminated with oil products were placed. The average concentration of petroleum products is 11.06 mg / kg. The soil was moistened up to 60%, fertilizers (azofoska) were introduced in the form of a 0.03% solution. By sprinkling, 6 kg of Destroil biological product were introduced once in the form of a 0.06% suspension. The cleaned soil was regularly moistened, loosened and a fertilizer solution was applied once every 2 weeks. In November 2009, soil samples were taken to determine the residual oil content. The average concentration of oil products was 3.02 mg / kg, the cleaning efficiency of 72.7%. The work card was released for the next portion of the soil being cleaned.

Example 3. In May 2009, at the experimental production sites No. 3 “B” (1 ha) and No. 5 (2 ha) with a clay screen, oil sludge from earth pits of Russian Railways was placed. On pl. No. 3B - 2500 tons of oil sludge and 2500 tons of sand, on Sq. No. 5 - 5000 tons of oil sludge and 5000 tons of sand, after the mixture was distributed over the site, soil samples were taken from both sites to determine the content of oil products.

The average concentration at site No. 3 "B" was 99 mg / kg, at site No. 5 106.4 mg / kg. The soil was moistened up to 60%, fertilizers were applied, azofoska in the form of a 0.03% solution. By sprinkling, 6 kg of Destroil biological product was introduced at platform No. 3B in the form of a 0.1% suspension, at platform No. 5 12 kg. The soil to be cleaned was regularly moistened, loosened and a fertilizer solution was applied once every 2 weeks.

After 1.5 months, the soil was re-treated with a biological product similar to the first treatment. The remaining 4.5 months produced only watering and mineral fertilizing. In November 2009, soil samples were taken to determine the residual oil content. The average concentration of oil products at site No. 3V was 10.9 mg / kg, at site No. 5 31.8 mg / kg, the cleaning efficiency at site No. 3B was 89.9%, and at site No. 5 71%.

After microbiological cleaning, the soil was used for sanitary dumping of landfills for placement of solid household waste, dumping of roads and sumps, embankment of bush sites, filling quarries and sludge pits, elimination of ravines, landscaping and other construction works, and also as a soil structurer when performing work on reclamation.

The technical effect is the neutralization of oil-contaminated land and oil sludge with the rational use of the area allocated for microbiological treatment, effective and environmentally friendly treatment at different degrees of pollution at the same time, without the use of additional special equipment, with minimal labor and time to prepare the soil to be cleaned due to the method in which, as the formation of individual work sites, from each produce sampling of the delivered soil for oil content products, the results of which are fed through the recorder to the analysis unit, which, after comparison with the normative data, gives out personal recommendations through the additional calculation unit about the required amount of the structurer and the necessary amount of fertilizers and biological product for preparing the cleaned layer at this work site; fertilizers are applied to the soil mass prepared at the site in the form of a 0.07-0.1% solution, at the rate of 0.5-1 g / m ² ; conduct periodic sampling of the cleaned layer for the content of petroleum products from individual work areas, according to the results of which the calculation unit gives quantitative recommendations for the additional introduction of ingredients into the cleaned layer of each work area or a command to release this work area for the next portion of the cleaned soil.

Claims (4)

1. A method of neutralizing oil-contaminated lands and oil sludge by mixing the soil to be cleaned with a builder, for example sand or sawdust, fertilizer and a biodestructor, characterized in that, as separate work sites are formed, samples of delivered soil are collected from each for the content of oil products, the results of which are fed through the recorder into the analysis unit, which, after comparing with the normative data, gives out through the additional calculation unit personal recommendations about the required number of pages kturatora and on the required quantity of fertilizer and a biological product to be purified preparation layer to a given operating station; fertilizers are added to the prepared soil mass in the form of a 0.07-0.1% solution at the rate of 0.5-1 g / m ² ; conduct periodic sampling of the cleaned layer for the content of petroleum products from individual work areas, according to the results of which the calculation unit gives quantitative recommendations for the additional introduction of ingredients into the cleaned layer of each work area or a command to release this work area for the next portion of the cleaned soil. 2. The method according to claim 1, characterized in that the biological product "Destroyl" (a strain of bacteria Acinetjbacter sp. JN-2) is used as a biodestructor in the form of 0.06-0.1% suspension at the rate of 0.5-1.5 l / m ² . 3. The method according to claim 2, characterized in that the suspension is prepared by preliminary mixing the calculated amount of the drug with a small amount of water, followed by dilution in a 0.04-0.1% solution of nitrogen-phosphorus fertilizers, aeration for up to 6 hours with periodic 2-3 hours, vigorous stirring for 20-30 minutes. 4. The method according to any one of paragraphs.2 and 3, characterized in that the biological product "Destroyl" is applied to the cleaned layer by sprinkling - in the form of a suspension prepared in a ratio of 0.6-1.0 g of the drug per 1.0 l of industrial water.