| Crude oil as a kind of rare non-renewable resource to the country’s economic development, science development and national defense construction, has very important significance. With the development of production technology in recent years, most oil fields in our country have entered the stage of tertiary oil recovery. Oil resources are less and less, the water content increasing, coupled with the use of all kinds of oil displacement agent to make the crude oil emulsion system more complex, higher stability. The performance requirements of the demulsifiers are stricter. High efficiency and wide applicability demulsifier has been widely studied, in order to ease the increasingly severe resource shortage problem.Firstly, the paper through telomerization method prepared a series of low hydrogen silicone oil with different hydrogen content. In the process of hydrogen addition reaction with polyether, the higher hydrogen silicone oil has higher reactivity, easily to cause crosslinking. The lower hydrogen silicone oil has poorer reactivity. At the same time, the grafted polyether is smaller, adverse to the demulsification performance of product. Compared and chose the hydrogen silicone oil with 0.1% hydrogen content as raw materials for the subsequent graft products. The product is analyzed by IR and 1H NMR.Through the silicon hydrogen addition reaction, connected the low surface tension and hydrophobic hydrogen silicone oil with the hydrophilic allyl polyoxyethylene polyoxypropylene epoxy ether and allyl polyoxyethylene polyoxypropylene ether. The multi branched demulsifier for crude oil with polysiloxane as main chains, polyether as branched chain was prepared. The structure of the product was characterized by IR and 1H NMR. The best reaction process conditions were explored as follows: the molar ratio of silicon hydrogen bond and carbon double bond was 1:1.20, reaction temperature 110 ℃, the reaction time of 5 h, the amount of catalyst was 30 μg/g(relative to the total mass of reactants), dosage of solvent for 40% of the total raw material. Under the experimental conditions, the reaction conversion rate reached 93.67%.The epoxy groups at the ends of branched chain polyether crude oil demulsifier react with trimethylamine hydrochloride for open loop quaternary ammonium reaction, the polyether quaternary ammonium polysiloxane demulsifier with the end of polyether containing quaternary ammonium salt was prepared. The structure of the product was characterized by IR and 1H NMR. The best reaction process conditions were explored as follows: the molar ratio of hydrochloride and epoxy group was 1.10:1, reaction temperature 60 ℃, the reaction time of 4 h, dosage of solvent for 60% of the total raw material. Under the experimental conditions, epoxy open loop quaternary ammonium reaction conversion rate reached 97.67%.Using Yanchang Petroleum Group Yanan crude oil simulated the crude oil emulsion to evaluate the performance of homemade branched polyether demulsifier and polyether quaternary ammonium polysiloxane demulsifier. Determined the best ratio of epoxy ether with methyl ether was 3:1. The optimal proportion of quaternary ammonium salt with methyl ether 1:2. Under the condition of demulsifier dosage 100 mg/L, demulsification temperature 60 ℃, demulsification time 2 h, branched polyether demulsifier dehydration rate reached 86.71%, oil in water content was 546.29 mg/L, oil-water interface was breezing; Polyether quaternary ammonium polysiloxane demulsifier dehydration rate reached 89.67%, oil in water content was 326.94 mg/L, oil-water interface was clear; Branched polyether demulsifier dosage 40 mg/L and demulsifier BQ-05 dosage 60 mg/L for compoud, dehydration rate reached 91.56%, oil in water content was 246.17 mg/L, oil-water interface was clear; Polyether quaternary ammonium polysiloxane demulsifier dosage of 50 mg/L and demulsifier SP169 dosage of 50 mg/L for compoud, dehydration rate reached 96.43%, oil in water content was 166.78 mg/L, oil-water interface was clear. |
PDF Full Text Request