PT115730B - PROCESS FOR THE BIOREMEDIATION OF POLLUTANTS DERIVED FROM OIL AND/OR GAS WELLS - Google Patents

Abstract

THE PRESENT INVENTION REFERS TO A METHOD FOR THE BIOREMEDIATION OF AN AREA POLLUTED BY THE ACTIVITY OF OIL AND/OR GAS EXTRACTION IN THE REFERRED AREA AND THAT CAUSES THE EMISSION OF POLLUTANT GASES IN THE AIR AND THE POLLUTION OF THE SOIL AND THE OIL-IMPREGNATED SUBSOIL , INCLUDING ONE OR MORE OF THE FOLLOWING PHASES: I) DEPURIFICATION OR PURIFICATION OF THE GASES PRODUCED BY THIS ACTIVITY; II) TREATMENT OF OIL-IMPREGNATED GROUNDS TO SEPARATE THE SLUDGE FROM THE OIL; III) SOIL IMPROVEMENT.

Description

DESCRIPTION

PROCESS FOR THE BIOREMEDIATION OF POLLUTANTS DERIVED FROM OIL AND/OR GAS WELLS

TECHNICAL FIELD OF THE INVENTION

[0001] The present invention concerns the application in the field of treatment, in particular, the treatment of areas where petroleum activities were carried out.

STATUS OF THE TECHNIQUE

[0002] Among the increasingly serious problems linked to oil extraction activities, the serious environmental pollution caused by these activities stands out and whose effects remain, even when the exploration of a well is finished.

[0003] Some companies, nowadays, undertake to recover the oil that comes separated from the impurities by means of filters or centrifuges; the sludge that is produced is subsequently rendered inert by means of chemical and cement aggregates, thus to form useful materials for reuse in road construction, paving or fences.

[0004] However, methodologies that offer closed-loop solutions for this problem are not yet available.

SUMMARY OF THE INVENTION

[0005] The objective of the present invention is to disclose a complex method capable of acting simultaneously with the activities of exploration of oil wells and of gas wells, avoiding, therefore, that at the end of the exploration of the deposit or reservoir, the soil, the subsoil, the water table and the air become permanently damaged or irreparably compromised because of the polluting agents.

OBJECT OF THE INVENTION

[0006] In a first object, the invention relates to a method for the improvement, remediation, recovery, treatment or improvement of places polluted by oil and/or gas wells.

DESCRIPTION OF THE FIGURES

[0007] For an easier understanding of the invention, the figures are attached in annex, which represent preferred embodiments of the present invention, but which, however, do not intend to limit the object of the same.

[0008] Figure 1 shows the well location scheme within the perimeter of the area targeted by bioremediation. The reference signals refer to the following technical characteristics:

.1; 5.2; 4.1; 3.1; 7.1; 8.2; 8.1; 6.1; 6.2 refer to peripheral wells in area IA;

, 2.1, 3, 4, 5, 6, 7 and 8 refer to transfer wells in area 1B;

and the reference signal 1 refers to the base well.

[0009] Figure 2 shows, in graph, phases 2 and 3 of the method of the present invention, in which:

Area IA refers to the peripheral well;

Area 1B refers to the transfer well;

Area 1C refers to the base well;

1.7 - Storage of oil separated from sludge;

1.6 - Mobile oil-sludge separation zone;

1.8 - Storage of separated oil sludge;

1.5 - Dirty oil accumulation tank;

1.1 - Gas scrubber;

1.2 - black camping water purifier;

1.3 - Combined heat and energy (CHP);

1.4 - afterburner;

1.9 - Pyrogasifier;

I - oil pipeline;

II - Dirty oil;

III - oil well;

IV - Gas combustion torch;

[0010] Figure 3 is a representation of phases 1, 2 and 4 of the method of the present invention, in which the reference signals refer to:

A - Phase 1;

B - Phase 2;

C - Phase 4;

D - Core drilling for earth sampling;

Ε - analysis;

F - Enzyveba®;

G - Anenzy®;

H - Hot cold;

J - Electricity;

3.4 Diagnostic Project;

3.5 Executive Project;

3.1 Pyrogasifier;

3.2 Biogas + Humus + Anenzy® + Enzyveba®;

3.3 Mineral organic bioremediating substrate;

3.7 Accumulation of polluted land;

3.6 Scraping off a layer of polluted oil

3.8 Second scraping with less polluted layer removal;

3.9 Cumulus in aerobic bioremediation with Enzyveba®;

3.10 Herbarium and absorbent agricultural cultivation with Aenzy® and Enzyveba® humus;

3.14 Perimeter plants around grass and sunflowers;

3.15 Overflow of bioremediated land enriched with organic-mineral substrate;

3. 16 Plant-absorbing agricultural crops for finishing bioremediation.

DETAILED DESCRIPTION OF THE INVENTION

[0011] According to a first object, the present invention describes a method for the improvement, treatment or recovery of places polluted by oil and/or gas wells.

[0012] For the purposes of this invention, the term bioremediation is used as a synonym for enhancement or improvement or regeneration or treatment even if, in comparison with the latter, it has a broader meaning in relation to a complex of activities aimed at restoration or even the improvement of conditions at a site after oil and/or gas exploration.

[0013] The place, according to the present invention, can again be used for agricultural and/or residential activities.

[0014] The two terms, therefore, are here used interchangeably.

[0015] The local meaning is that of an area of territory that has suffered the effects of oil and/or gas extraction activities.

[0016] The area therefore includes soil, surface terrain, subsoil and water table.

[0017] In one embodiment, the subsoil expands to an adequate, optimal and sufficient depth for the elimination of pollutants, as will be described below.

[0018] In another embodiment, the wells are organized according to the following classification:

- base (or central) well; in an optimal position in relation to the other wells, and therefore preferably central. In its immediate vicinity are placed the pyrogasifier and structures for the production of electricity.

- peripheral well: situated distally;

- transfer well: located in an intermediate position between the base well and the peripheral wells. In particular, one or more peripheral wells may converge into a single transfer well.

[0019] In another embodiment, the assignment of the base, transfer or peripheral well function is established depending on the reciprocal distance of the wells and, therefore, the possibility of managing them in the most efficient and timely manner, depending on the pollution of the area in the immediate vicinity of the well and the estimated life of the well itself, that is, how long the oil and/or gas exploration is expected.

[0020] According to a preferred embodiment, the method of the present invention comprises several stages.

[0021] Among these, are recognized mainly: a preliminary phase and an operational phase.

[0022] In turn, each of the phases comprises more phases (or sub-phases), as will be described below. First Preliminary Phase

[0023] This phase includes the aforementioned diagnosis, that is, the verification of the site and documents, to define the project and its schedule.

[0024] All necessary actions must be carried out to characterize the state of air, soil, subsoil and groundwater pollution.

[0025] To this end, appropriate chemical and microbiological analyzes may be carried out.

[0026] At the end of this phase, the Nm3 of gas to be treated can be quantitatively evaluated, as well as the composition of the gases, the m3/day of spilled oil and/or produced sludge to be treated.

[0027] In another embodiment, considering the times in years of gas and oil/sludge production of the well under analysis, data can be prepared for the dimensioning of the necessary facilities and machinery.

[0028] In another embodiment, simulations of installations can also be made for each operational phase according to the principle of Q-T-S (Quantity, Time, Space: Q = Amount of masses to recover; T = Operating time to dedicate to the technology /process; S = Space to dedicate towards available/needed surfaces).

[0029] In another embodiment, a financial plan and a positive and negative Environmental Impact Assessment (VIA) may also be prepared.

[0030] Second Preliminary Phase

[0031] At this stage of the project, it is completed with the realization of all the necessary structures.

[0032] In one embodiment, the most operational part of the method is the one that includes the typical activities and recovery features, which distinguish this invention and differentiate it from already known processes.

[0033] In another embodiment the first operational phase comprises one or more operational interventions.

[0034] In one embodiment, one of these (operational phase I)) refers to the purification of gases produced by oil and/or gas extraction activities, through a collection and purification facility that is positioned directly above the well before the torch.

[0035] In another embodiment, once captured, the gas generated by the well is sent to the depurative treatment or purification phase, which includes:

a) a countercurrent washing step with micronebulized water;

b) a condensation stage by which dirty washing water is obtained;

c) a cryogenic phase for the elimination of pollutants;

d) an osmotic phase for the purification of dirty wash water.

[0036] By means of this process a purified gas and some residual products are obtained.

[0037] In another embodiment, the water to be used in the purification plant is in turn obtained by means of a modular biological purifier (MES-WP U&I Marcopolo Ecotone System Water Purification Urban and Industry).

[0038] Well water or properly desalinated sea water can also be used, if available.

[0039] For the purposes of this invention, the gas subject to purification may also be the gas obtained by the combustion (burning of the torch or incineration) of the torch or by the power plant (see below).

[0040] In another operational phase (operational phase II)), carried out simultaneously or after the other operational phases, the soil or soil impregnated with oil is treated.

[0041] For example, so-called ponds or small lakes can be treated, consisting of purges (or purges) of liquid oil, chemicals used in drilling processes and drilling debris that accumulates in special buried tanks.

[0042] These accumulations are treated in order to separate the oil, formed by liquid petroleum residues, and the mud, formed by dirty soil and/or impregnated with oil.

[0043] For this purpose, a mobile installation mounted on a rail can be used, which performs the separation on the basis of molecular weight.

[0044] In particular, the oil itself represents a commercial product, while the sludge can be stored for eventual disposal and/or recovery.

[0045] In a successive phase (operational phase III)) soil recovery is implemented through a microbiological and agronomic bioremediation program.

[0046] In particular, the microbiological recovery is obtained through a first phase of scraping the soil that was in contact with oil (in the said small lakes) at a depth determined by the surveys carried out in the first phase.

[0047] The scraping can be superficial, that is, from 1 cm to 20 cm or deep, that is, beyond 20 cm and up to 10 meters, preferably 5 meters and even more preferably up to 4, 3, 2 or 1 meter or up to 50 cm.

[0048] The depth of scraping essentially depends on the concentration and type of pollutants present.

[0049] Different mounds of ground or soil are formed depending on the degree of pollution of the ground or soil removed, as well in a particle where the ground or soil has been scraped off.

[0050] Even the least polluted land or soils are subjected to a scraping phase.

[0051] The soils accumulated after scraping are successively treated with a bioremediating substrate.

[0052] In particular, a mixture is prepared consisting of about 90% of soil or soil and about 10% of bioremediation substrate.

[0053] In addition, the soil or soil thus prepared is treated with an aqueous solution of a bioactivator system (Enzyveba NK1, Marcopolo), represented by a microbial consortium.

[0054] Also the particles (zones) from which the earth (ground or soil) was scraped are treated by making a layer of bioremediator of about 10 cm, which is preferably buried, at a later time, with a special machine at a depth of about 10 cm. 100 mm.

[0055] Thanks to its composition, the bioremediator is very rich in microbial, bactericidal and fungicidal agents that are specialized:

- in degrading hydrocarbons, and

- act as a soil improver for the recovery of agricultural crops.

[0056] Also, the ground scraped and eventually treated is aerated continuously in order to keep the temperature and humidity constant.

[0057] In a preferred aspect of the invention, further aid for recovery is offered, also in addition to periodic spraying with Enzyveba NK12 (Marcopolo Engineering S.p.A.) also with a spraying of the areas with an aqueous solution of Humus AnEnzy ® (Marcopolo Engineering S.p.A.) .

[0058] This can be done both in areas where the soil or soil has been removed by scraping and in the reconstitution terrain.

[0059] In the phase of the said agronomic recovery, the cultivation of a large herbarium in cyclical plots continues, depending on the availability of water.

[0060] It is also possible to sow crops of varieties known for high absorption, such as sunflower, hemp, ficus (Benjamin).

[0061] Once the herbarium cycle is over, the vegetation can be shredded and eventually buried in the first 20 cm of thickness of the terrain or soil.

[0062] In a preferred aspect of the invention, 3 to 4 cycles of agronomic bioremediation are required to achieve land purification or regeneration.

[0063] According to one aspect of the invention, in the areas that need it, it is possible to demarcate the intervention area with native shrubs and plants, to defend the recovering land against the invasion of sand.

[0064] Eventually, also woody (or wooden) essences typical of desert areas can be used.

[0065] The lightly polluted earthen mounds, once purified or regenerated, can be used to reconstitute scraped land portions.

[0066] In a period of time of about 10-20 years, the primary recovery is completed, which can be followed by the phase of planting native plants mixed with native shrubs throughout the area and, therefore, not only along the perimeter.

[0067] The amplitude (or size) of the purified areas essentially depends on the intensity of the pollution and will therefore be very intensive in the areas close to the well and in the spill areas, while it will be more limited in the surrounding areas polluted only by the majority of the deposit. well atmosphere.

[0068] In this regard, in fact, an area of about 10 km around each well is cyclically wetted or sprayed with an aqueous solution of Enzyveba NK12 for a period of about 3 months, preferably in the evening hours.

[0069] According to the present invention, it is also possible to carry out the recovery of waste products that derive from the remediation activities carried out.

[0070] In a particular embodiment:

the recovered and purified gas as described above is used for the production of electrical energy in heat engines;

- the purified or purified oil is destined for the market, because it represents a commercial product in itself;

- once the cycle (vital or useful for present purposes) of the plant varieties with a high absorption capacity has ended, they are cut and sent to the pyrogasifier;

- portions of mounds of mostly polluted land, kept covered by a polyethylene film, are periodically removed to be destined for pirogasification;

- the sludge produced is treated in a pirogasifier.

[0071] In particular, the pyrogasification of the sludge gives rise to a gas, which in turn is subjected to a depuration or purification procedure before being sent to the electric current or hot water generation phase.

[0072] In addition to the gas, the pyrogasifier produces the so-called biogas.

[0073] With regard to biogas, it is used as an aggregator in a bioremediation product that comprises:

- a restructuring and conditioning compound (organic fertilizer) composed of mixed soil, derived from the fermentation (controlled fermentation using the Pfeiffer method) of selected bovine manure from livestock and agricultural plant by-products.

[0074] In a preferred aspect of the invention, in this regard, the product Humus AnEnzy® (Marcopolo Engineering S.p.A) is used.

a bioactivator comprising a microbial consortium.

[0075] In this regard, the product Enzyveba® (Marcopolo Engineering S.p.A.) is preferably used.

[0076] The obtained mixture represents a complex product with bioremediation capacity thanks to the content rich in organic and mineral compounds, as well as in specialized autochthonous microbes.

[0077] From the above description the advantages offered by this invention are evident.

[0078] In particular, a first aspect refers to the possibility that all oil and gas extraction activities do not need to be interrupted to allow land or soil recovery.

[0079] In fact, the bioremediation methodology described here operates not only after but also during the exploration activities of wells and deposits or reservoirs.

[0080] In fact, most of the activities are practically concluded when the extraction activity is concluded, so the area concerned is almost completely requalified and returned to society.

[0081] The present invention allows the recovery of land and territory, the recovery of gas and biogas, as well as the waste represented by sludge and oil.

[0082] In addition, the elimination of air pollution, allows the reduction of the amount of greenhouse gases and therefore contain activities against the ozone layer.

[0083] Furthermore, groundwater is better protected thanks to the method available to this invention.

[0084] The advantages are undeniable even in respecting and safeguarding human and environmental health.

[0085] The embodiments described above are combinable with each other.

[0086] The present invention is, of course, in no way restricted to the embodiments described in this document and a person with average knowledge of the area will be able to foresee many possibilities of modification of the same and of substitutions of technical characteristics for equivalent ones, depending on the requirements of each situation, as defined in the appended claims.

[0087] The following claims further define preferred embodiments.

Claims (10)

1. Method for the bioremediation of an area polluted by the oil and/or gas extraction activity in said area, which causes the emission of polluting gases in the air and the pollution of the soil and subsoil impregnated with oil, comprising the following phases: I) purification or purification of gases produced by this activity, which comprises the following phases: a) a countercurrent washing phase with micro-atomized water; b) a condensation stage by means of which the dirty washing water is obtained; c) a cryogenic phase for the elimination of pollutants; d) an osmotic stage for the purification of dirty wash water; II) treatment of soil impregnated with oil, comprising separating the sludge from the oil; III) soil improvement that includes a microbiological bioremediation phase comprising one or more of the following phases: - land spacing; -treatment of the soil removed by scraping with a bioremediation product; - ventilation of the ground removed; -treatment of the soil removed by scraping with a bioactivator product; - treatment of the ground surface of the areas after scraping with a bioremediation product. Method according to the previous claim, in which the scraping of the ground is carried out with a depth of approximately 1 cm to 20 cm. Method according to claim 1, in which the scraping of the ground is carried out with a depth of approximately 20 cm to 10 meters. Method according to the preceding claim, wherein the scraping of the ground is preferably carried out to a depth of up to 5 meters, preferably up to 4, 3, 2 or 1 meter or up to approximately 50 cm. A method according to claim 1, wherein said bioremediation product comprises a restructurer and mixed soil conditioning compound derived from the controlled fermentation of bovine manure. The method of claim 1, wherein the activator is a microbial consortium. A method according to any one of the preceding claims, wherein said stage III) comprises an agronomic bioremediation stage. A method according to the preceding claim, wherein the agronomic bioremediation stage of stage III) comprises one or more of the following stages: - growing a herbarium in the soil of said area; - crushing the grass and optionally burying the crushed material; - cultivation of plants with high absorption capacity. A method according to the preceding claim, wherein said plants with high absorption capacity comprise one or more of: sunflower, hemp, ficus Benjamin. Method according to the preceding claim 7, which further comprises the step of demarcating the treated area by planting native shrubs and/or plants.