Synthesis And Evaluation Of Organic Amine Clay Stabilizer

In this paper,epichlorohydrin/polyethylenepolyamine series clay stabilizers(ETP)were synthesized from epichlorohydrin,triethylenetetramine and polyethylenepolyamine.Carboxymethyl polyethylenepolyamine series clay stabilizers(CTP)were synthesized by the reaction of chloroacetic acid with diethylenetriamine,triethylenetetramine and polyethylenepolyamine respectively.Taking the antiswelling ratio of synthesized ETP and CTP clay stabilizer as the evaluation index,the effects of reactant ratio,reaction time and reaction temperature on the anti swelling performance of synthesized products were investigated by single factor experiment and orthogonal experiment,and the optimal synthesis conditions of synthesized ETP and CTP clay stabilizer were obtained.According to"SY/T 5970-2016,performance evaluation method of clay stabilizers for fracturing,acidizing and water injection in oil and gas fields",the anti swelling performance of synthesized ETP and CTP clay stabilizers was evaluated.The results showed that when the dosage is 2%,the anti swelling rate of ETP series clay stabilizers was more than 86%,and that of CTP series clay stabilizers was more than 91%,and the anti swelling performance was good.The results of rock debris recovery experiment and temperature resistance evaluation experiment showed that the synthesized ETP and CTP clay stabilizers had good dispersion inhibition ability,long-term effect and temperature resistance.The results showed that the six clay stabilizers had synergistic effect with KCl,NH₄Cl and Ca Cl₂,and the anti swelling effect was better than that of ETP and CTP clay stabilizers at the same concentration,but the erosion resistance was reduced.Thermogravimetric analysis,particle size analysis,scanning electron microscope analysis and XRD analysis were carried out on Na bentonite treated with untreated,distilled water and clay stabilizer solution.The results showed that the particle size of bentonite treated with ETP and CTP series clay stabilizers is significantly larger than that treated with distilled water,and the spacing between clay layers was smaller than that treated with water The mass loss of bentonite treated by ETP and CTP series clay stabilizers was significantly reduced at the same temperature.The mass loss of bentonite treated by ETP-2 was 0.60%at 200?and that of bentonite treated by ETP-3 was 0.78%at 225?,The mass loss of bentonite treated by CTP-1was 0.86%at about 200?,and that of bentonite treated by CTP-2 was 0.52%at 150?.It showed that the series of ETP and CTP clay stabilizers can be adsorbed on the clay surface,enter into the clay layers,wrap the clay particles,hinder the entry of water molecules,so as to bind the dispersion of clay and block the contact between water molecules and clay,and finally achieve the anti swelling effect.