The New Clay Stabilizer Synthesis

This paper in view of the present oil field water injection, acidizing clay stabilizer used in the job long-term problems such as lack of inhibition, synthesis of two kinds of organic clay stabilizer, and has carried on a series of performance evaluation and characterization of its structure. The experimental synthesis of a cationic clay stabilizer for the monomer through the aqueous solution polycondensation with epichlorohydrin and polyethylene polyamine, referred to as PTA1. By doing L9(3) orthogonal experiment, the optimum synthesis conditions:amine concentration (mass fraction) of3%, the molar ratio of1:7amine and epichlorohydrin, reaction temperature70℃, reaction time5h. Selection of anhydrous ethanol as solvent and purification agent, ethylenediamine and concentrated hydrochloric acid as monomers to produce another organic clay stabilizer of ethylenediamine hydrochloride. referred to as PTA2, optimum conditions for synthesis:mole ratio of concentrated hydrochloric acid and amine1:3, reaction temperature T=50℃, reaction time t=4h. Determination of the anti-expansion rate of the synthesis of two products, the results show that:under normal temperature, PTA1content is1%, rate of anti-swelling reached87.20%, when the amount of2%, anti-inflation rate is92.4%; PTA2has reached96.2%in amount of1%.According to oil and gas industry standards SY/T5971-94clay "stabilizers for water injection performance evaluation methods" on performance of anti-swelling conducted a series of evaluation:Determination of the rock debris recovery rate, shale swelling rate and core dissolution rate, show that the synthesis of two kinds of products have good stability and the ability to inhibit clay hydration swelling; Compound with inorganic salts, etc, the results show that when PTA1compound with NH4CL, PTA2with KCL have better anti-swelling effect, it not only improve the anti-expansion rate of the system, but also reduce the amount of organic clay stabilizing agent; Evaluation of using the washing anti-swelling agent long-term stability of clay, the results showed that the synthesis of two kinds of clay stabilizer with good long-term stability of clay, anti-swelling agent at different concentration, the91%rate of resistance to washing above. Product temperature resistance, acid and alkali resistance can be good.Infrared spectrum analysis on two products, the results show that the laboratory has designed synthetic polymer molecular structure, are the target products. Determination of the surface tension of the water, indicates that the product of two different concentrations on the surface tension of water is reduced to a certain extent. According to SY/T5762-1995"performance evaluation of fracturing and acidizing clay stabilizer method" on two product series of evaluations, results indicate that the product has good water solubility, acid solubility, with other additives of fracturing fluid or acid has a good compatibility; The1%products to join the fracturing fluid base fluid, determination of the viscosity, and there is not much change, shows two kinds of clay stabilizer can be applied to the construction of fracturing fluid.