The Study Of The Formation Mechanism Of Silicon Scale In The Water Injection System Of The Xinchun Oil Production Plant And Screening Of Scale Inhibitor

The appearance of oil field scale will affect the normal production of oil fields and impede the growth of economic benefits.Therefore,it is significant to study the formation cause and influence factors of oil field scale and to understand and solve the problem of fouling in oil fields.In this paper,the problem of scaling in the water pipeline of Chunfeng oil field in Xinchun oil production plant is explored,the main factors affecting the formation of silicon scale in the pipeline and the main factors affecting the formation of silicon scale are studied,and by selecting suitable inhibitors to provide theoretical guidance for future scale prevention and treatment work.Due to the differences in oil reservoir environment,mining and water treatment process,leading to the types and causes of scaling is not the same.In this paper,through the analysis of the scaling products and produced water,and forecast the scaling trend,and combined with the field mining method,the geological characteristics and the rock types of the reservoir,the fundamental reason for the scaling of the pipeline is that the high temperature steam will corrode the reservoir minerals and increase the content of the scaling ions in the produced water,which provides the material basis for scaling.In the process of pipeline flow,the deposition of silicon scale is formed due to the change of temperature,pressure,flow rate and other conditions.The formation of silicon scale is influenced by many factors.This paper studied the influence of pH value,temperature,calcium and magnesium ions and bicarbonate on silica scale formation,and by measuring the change of electrical conductivity with pH and temperature,and analyzing the scaling products under different systems and different factors,This paper studied the influence of pH value,temperature,calcium and magnesium ions and bicarbonate on silica scale formation,and the change of the conductivity with the temperature and pH value and analysis of the different system of different factors of fouling products,obtained the following conclusions: The lower the temperature and pH value,the lower the equilibrium concentration of silicon dioxide,the more easy the system is to scale.Calcium and magnesium ions can promote the formation of silicon scale and the magnesium ions are more likely to promote the deposition of silicon.In the high pH system,calcium and magnesium ions and silicic acids in the system directly produce insoluble silicate precipitation,and the phenomenon of calcium and magnesium silicon co deposition occurs.Under neutral conditions,the calcium and magnesium ions with positive charge can promote the coaglulation of silicon dioxide particles with negative electricity,and the formation of the scale is amorphous silicon dioxide.The influence of bicarbonate on silicon formation is related to the pH value and temperature of the system.Under the low pH value,the main composition of the scaling product is silica scale.Under the condition of high pH value,if bicarbonate content is low and the total consumption of calcium and magnesium ions can not be completely consumed,the main composition of the scaling products is the mixed scale of carbonate and silicate.When the bicarbonate content increased,calcium and magnesium ions were completely consumed,then the main component is the product of carbonate scaling.In the neutral system,the temperature reduction of silicon scale is more easily formed.The scale inhibition effect of scale inhibitor DQI is the best by screening seven kinds of market scale inhibitors.The optimum application conditions and parameters are the reaction temperature 60 C,the dosage of 320mg/L,the reaction time 20 h.By measuring the variation of turbidity,particle diameter and zeta potential of the drug before and after that,it is proved that the scale inhibitor DQI can inhibit the growth of silica gel particles to a certain extent,prevent the polymerization of silicic acid,so as to achieve the purpose of scale inhibition.By measuring the infrared spectrum of the scale inhibitor DQI,the main functional groups can be obtained as carboxyl,ether and sulfonic groups.The micromorphology of the scaling products before and after the addition of the drug was observed by SEM,and it was proved that the scale inhibition mechanism of the drug was mainly chelating and dispersing.