Highly effective viscosity-reducing agent for thermodynamic oil extraction process

Abstract

High efficiency viscosity-reducing agent which is used on THE thermal oil extraction technology, which is formed by the following raw materials with percentage by weight, firstly phenyl benzene, fused ring aromatic hydrocarbon or fused ring aromatic hydrocarbon derivative which does not contain chlorine element and sulfur element, secondly liquid petroleum product whose aromatic hydrocarbons content is no more than 5%, petroleum resin which is liquid state under the constant temperature or hydrocarbons natural aggregation which is particle state under the constant temperature, thirdly water-soluble anionic surface active agent, water-soluble non-ionic surface active agent, oil solubility anionic surface active agent or oil solubility non-ionic surface active agent, fourthly fusel oil, fifthly alcohol ether, sixthly oil solubility or water-soluble polymer which respectively has nonpolar portion which has eutectic crystal with ceresin wax molecular and polar portion which can make wax crystal system twisty on main chain and or branch chain, seventhly hyperoxide, eighthly carbamide, ammonium carbonate, ammonium acid carbonate or ammonium nitrite and ninthly ketone. The high efficiency viscosity-reducing agent has strong suitability, strong viscosity-reducing ability, safety and reliability, can largely reduce extract cost and increase the yield of oil pump, and increases the final recovery efficiency of oil reservoir.

Description

technical field [0001] The invention relates to a petroleum recovery additive, in particular to a high-efficiency viscosity reducer used in thermal oil recovery technology. Background technique [0002] At present, the thermal oil recovery process is mainly used in the recovery of heavy oil and high pour point oil, and viscosity reducers are generally used as auxiliary agents. The existing viscosity reducers are usually divided into water-based viscosity reducers and oil-based viscosity reducers. Water-based viscosity reducers are further divided into water-soluble viscosity reducers, oil-in-water emulsion viscosity reducers, oil-based viscosity reducers The base viscosity reducer is further divided into oil-soluble viscosity reducer and organic solvent type viscosity reducer, all of which have different defects. [0003] The water-soluble viscosity reducer is mainly composed of surfactant and water, and has the following defects when used in thermal oil recovery technology...

AI Technical Summary

Problems solved by technology

[0003] The water-soluble viscosity reducer is mainly composed of surfactant and water, and has the following defects when used in thermal oil recovery technology: first, it mainly uses the principle of emulsification to reduce viscosity, and cannot directly dissolve asphaltenes, colloids, and wax crystals. The viscosity-reducing effect is limited; second, it is difficult to automatically diffuse into the crude oil after being injected into the oil layer from the oil well; third, there is no effect or the opposite effect when the crude oil in the oil layer has a low water content

[0004] The oil-in-water emulsion viscosity reducer is mainly composed of surfactants, water and organic solvents. It has the following defects when used in thermal oil recovery technology: First, it mainly uses the principle of emulsification to reduce viscosity, directly dissolves and breaks asphaltenes, Colloids and wax crystals have limited ability to reduce viscosity; second, it is difficult to automatically diffuse into the crude oil after being injected into the oil layer from the oil well; third, the effect is extremely poor or opposite when the water content of the oil layer is low; The oil emulsion immediately delaminates under the heating of high-temperature fluid, and the synergistic injection construction process cannot be realized

[0005] Oil-soluble viscosity reducers are mainly composed of oil-soluble pour point depressants, organic solvents, etc., and have the following defects: First, although oil-soluble viscosity reducers can inhibit or disperse wax crystals, colloids, and asphaltenes, they cannot make them reach the true level. The size of the sol particles has a limited ability to reduce viscosity; the second is that its flash point is low, and there are construction safety problems when it is injected with high-temperature fluid; the third is that it is highly targeted and the workload of the screening test is large; the fourth is that it cannot solve the emulsification existing in the oil layer. Particle clogging; Fifth, there is a problem of timeliness, that is, its viscosity-reducing ability will continue to decrease with time; Sixth, its high cost makes it difficult to apply large doses in thermal oil recovery processes

[0006] Organic solvent-type viscosity reducers are mainly composed of hydrocarbon organic solvents, and have the following defects: first, they have limited solubility for wax crystals and colloids, and extremely poor solubility for layered asphaltene, so their viscosity reduction capabilities are limited; The flash point is low, and there are construction safety problems when it is injected with high-temperature fluid; third, it is difficult to suppress the geometric size of asphaltene and wax crystal structure; fourth, it cannot solve the problem of emulsified particle clogging in the oil layer; fifth, it has timeliness The problem is that its viscosity-reducing ability will continue to decrease with the extension of time; the sixth is that the addition amount is too large, resulting in a significant increase in production costs, and it is difficult to be practical in thermal oil recovery processes

[0007] In short, the existing viscosity reducers have poor practicability in thermal oil recovery technology and are difficult to apply on a large scale