Using micro-seepage structures to mitigate salt crystallization in brine transport systems

GAO Zhenjun; LIU Hai; DAI Sheng; REN Jian; LI Hao; ZHOU Xiumei; OYBEK Ishnazarov; ZHANG Lisheng; ZHANG Jianbo

doi:10.13522/j.cnki.ggps.2024401

Abstract：[Background and Objective]Brine,a high-salinity water body with a mineralization degree greater than 50 g/L,is rich in various chemical elements and holds significant developmental potential.In agriculture,brine can be used for soil improvement,water-saving irrigation,and fertilizer production.However,during the collection and transportation of brine,salt crystallization often occurs,particularly on the pipe walls.Factors such as temperature,flow rate,and surface roughness contribute to salt crystal deposition,reducing transportation efficiency and severely impacting the stability of irrigation systems.This paper proposes a physical method for preventing crystallization based on micro-seepage structures.[Method]An experimental platform based on micro-seepage structures was designed and constructed to conduct both static and dynamic crystallization experiments.Measured data were used to analyze the micro-seepage characteristics of the structures and assess the impact of different micro-seepage rates on crystallization on the pipe wall under both static and dynamic conditions.[Result]Under static conditions,varying water head can be used to control the micro-seepage rate.Increasing the water head significantly delayed the onset of crystallization on the pipe wall and reduced the amount of crystallization.Micro-seepage experiment showed that the solution could seep through the micro-seepage structure,forming a micro-wetting layer near the pipe wall.The thickness of this layer increased as the micro-seepage rate increased.Under dynamic flow conditions,crystallization on the pipe walls was significantly greater.However,when the micro-seepage pipe was used,increasing the pressure difference across the pipe reduced the crystallization mass on the wall.When the pressure difference was sufficiently large,no crystallization was observed on the wall.[Conclusion]The micro-seepage structure proposed in this paper effectively prevents crystallization on the pipe wall by forming a dilution layer on the wall surface.