High-argillaceous-content oil-containing sludge deep profile control agent and preparation method and application thereof
Technical Field
The invention relates to an oil-containing sludge profile control agent for profile control of deep cracks of an injection well in oil field production, in particular to an oil-containing sludge deep profile control agent with high shale content and a preparation method thereof, belonging to the technical field of profile control and water plugging of oil layers of oil fields.
Background
In oil field development, the production of associated products from oily sludge as crude oil has now become an important environmental factor. With the improvement of national requirements for environmental protection, the effective treatment of oily sludge has become an important problem in current oil field production.
In actual production, the oily sludge mainly comes from links such as tank cleaning of a storage tank, construction operation, maintenance operation, abnormal working condition leakage of the device and the like. These sludges are characterized by a high content of sludge, in addition to a certain amount of crude oil. The existing methods for treating the oily sludge mainly comprise two major types, namely oily sludge harmless treatment and sludge resource utilization technologies, wherein the oily sludge harmless treatment mainly comprises mechanical dehydration, biological treatment, solidification treatment and incineration landfill; the sludge resource utilization technology comprises an oil recovery technology, building material production and process utilization. In various technologies, the process utilization has low one-time investment cost and convenient operation, so the oily sludge profile control agent for water shutoff profile control is an important way for the current oily sludge treatment, and a plurality of technical researches are developed at home at present and certain effects are achieved. Secondly, the application is wide mainly including an oily sludge emulsifying suspension system and an organic gel type oily sludge system.
The most widely used oily sludge with high argillaceous content is the oily sludge emulsifying suspension system. The system utilizes mud components and oil components in the oil-containing sludge to block a pore passage formed by water injection and scouring of a water injection layer. According to the physical properties of the oily sludge, a proper amount of suspending agent is added to suspend solid particles in the oily sludge, so that the suspension time is prolonged, the injection depth is increased, and the plugging strength is improved. Adding a proper amount of additive, uniformly dispersing the oil components in the mixture to form uniform and stable emulsion, flushing the emulsion by formation water after the emulsion reaches a certain depth of the formation, adsorbing the emulsifier by formation rock, decomposing an emulsion suspension system, adsorbing colloidal particle wax by mud, forming a granular structure through adhesive aggregation, and settling and plugging a high-permeability layer in a large pore passage.
The organic gel type oily sludge system is mainly formed by mixing and crosslinking oily sludge and a polymer to form a gel system with certain strength and carrying capacity. If the oil-containing sludge is taken as a main agent, 0.1 percent of polymer and 0.1 percent of cross-linking agent are added, the gel-type oil-containing sludge deep profile control agent suitable for the oil reservoir condition at the temperature of 80 ℃ is developed, and after 90 days of maintenance at the temperature of 60 ℃, the viscosity can still reach 15000mPa & s; . For another example, lime powder is added to adjust the pH value to be neutral, 5% of oily sludge is mixed with 0.1% -0.3% of hydrophobic association polymer AP-P4 solution, and bactericide, stabilizer and cross-linking agent (urotropine, phenol and resorcinol) are added to prepare the polymer gel containing the sludge at the temperature of 60 ℃, wherein the gel strength can reach 723-49900 mPa & s.
Chinese patent publication No. CN104403648A discloses an oil-containing sludge profile control agent and a preparation method thereof, which are gel-type oil-containing sludge systems, but the adopted polymers and cross-linking agents are completely different; the invention adopts the organic chromium crosslinking agent to delay crosslinking, can achieve the aim of deep profile control, and can also obtain good profile control effect on oil-containing sludge with high argillaceous content. Chinese patent publication No. CN1927991A discloses a profile control agent for a water injection well, which is prepared by utilizing waste oil-containing sludge, is an oil-containing sludge emulsifying suspension system, and has different principles for preparing the profile control agent. Chinese patent publication No. CN101898860A discloses an inorganic composite profile control agent containing oil sludge and an application method thereof, wherein the inorganic composite profile control agent containing oil sludge is prepared by the invention as an organic composite profile control agent; the invention obtains the gel type oily sludge profile control agent through the interaction among the oily sludge, the polymer and the cross-linking agent, and the patent essentially obtains the profile control agent by an oily sludge emulsifying suspension method. Chinese patent publication No. CN103965848A discloses a composite profile control agent and a preparation method thereof, which are different from the principle of the present invention. Chinese patent publication No. CN104745162A discloses an emulsified and crosslinked oily sludge profile control agent, which selects cationic polyacrylamide, the invention uses zwitterionic polyacrylamide, crude oil in the oily sludge is emulsified by a cationic emulsifier, and can form electronic pairing with carboxyl of a polymer to bind the carboxyl on a polymer molecular chain, the cation of the polymer can also bind sludge with negative electricity on the molecular chain, and the oily sludge with high argillaceous content can also be prepared to obtain the ideal profile control agent.
Disclosure of Invention
The invention provides a high-argillaceous-content oil-containing sludge deep profile control agent and a preparation method thereof.
The technical scheme for realizing the aim of the invention is as follows:
a high-argillaceous-content oily sludge deep profile control agent comprises oily sludge, a cationic emulsifier, zwitterionic polyacrylamide (polymer), an organic chromium crosslinking agent, a reinforcing agent and a stabilizing agent.
The high-argillaceous-content oily sludge deep profile control agent disclosed by the invention further comprises a proper amount of water and/or a proper amount of bactericide.
Preferably, the high-argillaceous-content oil-containing sludge deep profile control agent comprises the following components in parts by weight: 10-30 parts of oily sludge, 0.1-0.3 part of cationic emulsifier, 0.08-0.4 part of zwitterionic polyacrylamide, 0.02-0.2 part of organic chromium crosslinking agent and 0.05-0.1 part of reinforcing agent; 0.01-0.04 part of stabilizer and 0.005-0.015 part of bactericide.
Further preferably, the high-argillaceous-content oil-containing sludge deep profile control agent comprises the following components in parts by weight: 15-25 parts of oily sludge, 0.15-0.25 part of cationic emulsifier, 0.15-0.3 part of zwitterionic polyacrylamide, 0.08-0.15 part of organic chromium crosslinking agent and 0.06-0.08 part of reinforcing agent; 0.02-0.03 part of stabilizer and 0.008-0.012 part of bactericide; further, the components also comprise water, and the total amount is 100 parts.
Preferably, the high-argillaceous-content oil-containing sludge deep profile control agent comprises the following components in parts by weight: 20 parts of oily sludge, 0.2 part of cationic emulsifier, 0.3 part of zwitterionic polyacrylamide, 0.1 part of organic chromium crosslinking agent and 0.08 part of reinforcing agent; 0.02 part of stabilizer and 0.01 part of bactericide; further, the components also comprise water, and the total amount is 100 parts.
The cationic emulsifier comprises one or more of alkyl amine or quaternary ammonium salt emulsifiers.
Further, the cationic emulsifier comprises one or more of octadecyl trimethyl ammonium chloride, octadecyl trimethyl hydroxypropyl ammonium chloride and the like.
Further, the organic chromium crosslinking agent includes chromium acetate and the like.
Further, the enhancer includes dicumyl peroxide and the like.
Further, the stabilizer comprises an oxygen scavenger and a heat stabilizer. The oxygen scavenger comprises one or more of thiourea, sodium thiosulfate, ammonium thiosulfate and the like; the heat stabilizer comprises one or more of polyvinyl alcohol, ethylenediamine and the like.
Further, the bactericide is preferably formaldehyde.
The sludge content of the oily sludge is 20-90%, and the preferable sludge content is 50-85%.
The invention also provides a preparation method of the oil-containing sludge deep profile control agent with high argillaceous content, which can be uniformly mixed according to a conventional method in the field. Specifically, the preparation method of the high-argillaceous-content oil-containing sludge deep profile control agent comprises the following steps:
1) mixing and stirring the oily sludge and a proper amount of water uniformly;
2) adding a proper amount of water into the zwitterionic polyacrylamide to prepare a polymer mother solution;
3) adding a cationic emulsifier into the oily sludge pretreated in the step 1) according to the proportion to prepare uniform and stable dispersion liquid; and respectively adding an organic chromium crosslinking agent, a reinforcing agent, a stabilizing agent and a bactericide into the mixture according to a ratio, adding the polymer mother liquor prepared in the step 2), and uniformly stirring to obtain the high-argillaceous-content oil-containing sludge deep profile control agent.
The weight parts in the invention can be the weight units known in the art such as mu g, mg, g, kg, and the like, and can also be multiples thereof, such as 1/10, 1/100, 10, 100, and the like.
The invention also comprises the application of the profile control agent in the oil exploitation process.
The gel formation is greatly influenced by the high sludge content in the oily sludge. In order to ensure that the gel of the oily sludge can meet the plugging requirement of a crack type water-breakthrough channel and reduce the pollution of the oily sludge to the environment, the invention develops the gel deep profile control agent of the oily sludge aiming at the oily sludge with high argillaceous content. The mechanism of the oil-containing sludge gel profile control agent is as follows: the crack type water shutoff requires that the plugging agent has better injectability and strength, and the polymer is a reasonable choice for meeting the aim of effectively treating the oily sludge. However, due to the fact that the sludge with high argillaceous content has great influence on polymers, and the cross-linking property of the anionic polymer is poor, the zwitterionic polyacrylamide is selected as an effective carrier of the oily sludge.
The amphoteric ion polyacrylamide is formed by hydrolyzing and copolymerizing vinyl amide and vinyl cationic monomer acrylamide monomers, and the chain not only has carboxyl negative charges after the hydrolysis of the acrylamide, but also has vinyl positive charges. Thus, a zwitterionic irregular polymer having both positive and negative charges on the molecular chain is formed.
The polymer and the oily sludge are organically fused and gelatinized, and the following steps are required to be completed:
(1) in the solution, crude oil in the oily sludge is emulsified by adopting a cationic emulsifier, and can form electron pairing with carboxyl in a zwitterionic polymer, so that the crude oil is bound on a polymer molecular chain; in addition, the sludge is negatively charged, forms electron pairs with cations in the polymer, and is also bound on the polymer molecular chain.
(2) The weak gel formed by crosslinking of the zwitterionic polyacrylamide still mainly depends on side groups COO on the molecular chain-The pairing of positively charged crude oil emulsified particles with carboxyl groups requires sacrificing some amount of carboxyl groups. Therefore, the fusion and the gelatinization of the zwitterionic polymer and the oily sludge require that the sludge amount is reasonably matched with the amphoteric polymer, the cationic surfactant and the crude oil, so that an oily sludge system with good fusion and enough strength is formed.
The invention has the beneficial effects that:
the high-argillaceous-content oily sludge deep profile control agent is an oily sludge profile control system taking a zwitterionic polymer as a carrier, is a gel system with high strength and strong capability of carrying oily sludge by gel, meets the requirement of profile control at the deep part of a crack, has the sludge content range of 20-90 percent in the oily sludge, the injection viscosity of 150-viscosity-increasing agents is 200mPa.s, and the viscosity at 65 ℃ is more than 60000 mPa.s. The maximum processing capacity of the oily sludge is 1000m3Polymer treatment 100-150m3Oily sludge.
Detailed Description
The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.
The sludge content of the oily sludge is 75%.
Example 1
The deep profile control agent for the oily sludge with high argillaceous content comprises, by weight, 10% of the oily sludge, 0.1% of octadecyl trimethyl ammonium chloride, 0.08% of zwitterionic polyacrylamide, 0.02% of chromium acetate, 0.05% of a reinforcing agent (dicumyl peroxide), 0.005% of thiourea, 0.005% of polyvinyl alcohol, 0.005% of formaldehyde and the balance of water.
The embodiment also provides a preparation method of the high-argillaceous-content oil-containing sludge deep profile control agent, which comprises the following steps:
1) mixing and stirring the oily sludge and a proper amount of water uniformly;
2) adding a proper amount of water into the zwitterionic polyacrylamide to prepare a polymer mother solution;
3) adding a cationic emulsifier into the oily sludge pretreated in the step 1) according to the proportion to prepare uniform and stable dispersion liquid; and respectively adding an organic chromium crosslinking agent, a reinforcing agent, a stabilizing agent and a bactericide into the mixture according to a ratio, adding the polymer mother liquor prepared in the step 2), and uniformly stirring to obtain the high-argillaceous-content oil-containing sludge deep profile control agent.
Example 2
The deep profile control agent for the oily sludge with high argillaceous content comprises, by weight, 20% of the oily sludge, 0.2% of octadecyl trimethyl hydroxypropyl ammonium chloride, 0.2% of zwitterionic polyacrylamide, 0.1% of chromium acetate, 0.07% of a reinforcing agent (dicumyl peroxide), 0.01% of sodium thiosulfate, 0.01% of ethylenediamine, 0.01% of formaldehyde and the balance of water.
Prepared in the same manner as in example 1.
Example 3
The deep profile control agent for the oily sludge with high argillaceous content comprises, by weight, 30% of the oily sludge, 0.3% of octadecyl trimethyl ammonium chloride, 0.4% of zwitterionic polyacrylamide, 0.15% of chromium acetate, 0.1% of a reinforcing agent (dicumyl peroxide), 0.02% of sodium thiosulfate, 0.02% of polyvinyl alcohol, 0.015% of formaldehyde and the balance of water.
Prepared in the same manner as in example 1.
Example 4
The deep profile control agent for the oily sludge with high argillaceous content comprises, by weight, 20% of the oily sludge, 0.2% of octadecyl trimethyl hydroxypropyl ammonium chloride, 0.3% of zwitterionic polyacrylamide, 0.1% of chromium acetate, 0.08% of a reinforcing agent (dicumyl peroxide), 0.01% of thiourea, 0.01% of polyvinyl alcohol, 0.01% of formaldehyde and the balance of water.
Prepared in the same manner as in example 1.
Experimental example 1 evaluation experiment of oil-containing sludge profile control System Performance
The high-argillaceous-content oily sludge deep profile control agent prepared in example 4 is taken for performance evaluation experiments, the influence of temperature on an oily sludge profile control system is researched, and the results are shown in the following table.
Temperature (. degree.C.)
|
Gel strength (mPa.s)
|
50
|
18000
|
65
|
62000
|
75
|
56000
|
80
|
42000 |
From the above table, it can be seen that the gel strength of the profile control agent decreases with increasing temperature, still reaching 42000mpa.s at 80 ℃, indicating that the profile control system can be applied at higher temperature.
Although the invention has been described in detail hereinabove with respect to a general description and specific embodiments thereof, it will be apparent to those skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.