Research On Moditication Of Acid Water Based On Microbubble Stripping Technology

The produced water in carbonate oilfield contains a relatively high concentration of dissolved CO₂gas,which makes the p H of the produced water to be weakly acidic,causing problems such as equipment corrosion and unstable water quality along the way.The conventional chemical modification technology not only has a high operating cost,but also produces some by-products,so the gas stripping method is more popular in some occasions.In this paper,combining the theory of gas-liquid equilibrium and classical mass transfer rate,on the basis of conventional stripping technology,based on the concept of“static turbulence dispersion and venturi crushing”,a new type of microbubble generator was innovatively designed and compared.And then test and verify the foaming performance and stripping modification effect.According to the static experimental research and kinetic analysis of CO₂dissolution and removal in water under conventional aeration and microporous aeration,this paper proves that reducing the bubble size is beneficial to improve the CO₂removal efficiency.In order to reduce the gas-water ratio and shorten the reaction time,on the basis of exploring the bubble formation performance of the static disturbing flow dispersive microbubble generator,through the"bubbles generated by static turbulence and swirl centrifugal degassing"of experimental platform for stripping modification,it is measured that the CO₂removal efficiency of the SV static mixer is about 80%at the optimal gas-water ratio of 2.0:1-3.5:1.In order to further reduce energy consumption and improve the effect of stripping modification,this paper designs and develops a new type of microbubble generator suitable for small gas-water ratio,compact structure and high performance.The equipment consists of two parts:a plate-type bubble-forming element and a venturi crushing element.The paper takes dispersion coefficient and equipment pressure drop as evaluation indicators,uses CFD numerical simulation and response surface method to optimize the structure of the plate-type bubble-forming element,and predicts and analyzes the bubble-forming performance of the new type of microbubble generator under the optimal structure.Numerical simulation prediction shows that the gas-liquid two-phase can be uniformly mixed and dispersed at the outlet of the new microbubble generator.Afterwards,xplore the bubble formation performance of the new type of microbubble generator based on indoor experimental methods.Under optimal conditions,the bubble size is measured to be between 100-150μm,the number of bubbles generated is sufficient and the number of micro-bubbles is as high as 90%.The"microbubble stripping and swirl centrifugal degassing"technology is used for acidic water modification treatment,and the influence of operating parameters and water quality parameters on the microbubble stripping effect is explored.The results show that when the gas-water ratio is 1:1,the CO₂removal efficiency can reach more than 80%.Increasing the temperature,lowering the p H value of the water body,and reducing the oil concentration are all conducive to improving the effect of stripping modification.On this basis,design the scheme of microbubble stripping modification and microbubble flotation for removing oil.Using microbubble stripping can realize the rapid and efficient removal of CO₂in produced water under small gas-water ratio.The related technologies can greatly reduce the construction investment and operation cost of the acid water modification system in oil field.It can also be applied to other technical fields,such as deacidification of drinking water and decarbonization of aquaculture water.