Study On Drag Reduction And Consumption Reduction Of Deep Underground Brine Mining Transport Process

With the continuous development of relevant brine industries, especially the rise of chlorine, bromine-based fine chemicals and the rapid increase of production capacity, the demand for brine resources increased. After decades of exploitation, shallow underground brine reserves showed a downward trend, the exploitation of deep underground brine will play a significant role in the elimination of constraints sustained development as the shortage of brine resources. Compared with shallow brine mining, deep well mining of brine mining exit large investment and high operating cost problems, in which the energy costs of deep brine mining process accounted for the largest proportion of total economic output costs. Seeking one or more DRA which can significantly reduction the energy consumption of brine mining process when added to the brine is of great significance in improving mining halogen process throughput, reducing energy consumption and economic cost.Mainly in the following aspects of drag reduction and consumption reduction of deep underground brine mining transport process were studied in this thesis.Through consulting relevant literature, this paper analyses the existing water soluble drag reduction mechanism and drag reduction performance, combined with the characteristics of high temperature and pressure, high salt in brine mining process, the basic performance applies of DRA were predicted that can be used in brine mining process for drag reduction; Designed and installed the drag reduction ring road based on the analysis on the mechanism of drag reduction performance test; The drag reduction performance of existing water-soluble polymer, such as PAM, xanthan gum, HPC, CMC, polyvinyl alcohol, PEO etc have been studied to preliminarily determine the drag reduction performance of all kinds of compounds; PAM was modified, including hydrolysis reaction and sulfomethylation, and the drag reduction performance of reaction product-HPAM AM and SPAM have been studied; The drag reduction performance of all kinds of DRA were analyzed to determine the most suitable DRA for the drag reduction of brine mining process.The results show that:1The drag reduction ring road that independent design and installation in laboratory is economical and practical, the test data is more accurate; Using electromagnetic pump instead of centrifugal pump for conveying power to avoid the shear degradation of polymer drag reduction agent.2Several common water-soluble polymers in the test, only the PAM and the PEO has significant drag reduction effect, and xanthan gum, HPC, CMC, polyvinyl alcohol has no drag reduction effect as their three-dimensional reticular structure or low molecular weight.3The drag reduction effect of PAM in low temperature water is outstanding, in the optimal conditions of Re and adding concentration, the drag reduction rate of PAM can reach above50%; Temperature has a greater influence on the drag-reducing characteristics of PAM, drag reduction rate fell sharply as the of temperature increases; The brine salinity has the same greater influence on the drag-reducing characteristics of PAM; Under the dual effects of temperature and salinity, the drag reduction performance of PAM significantly reduced; Under the condition of50℃, salt content of200g/L, the maximum drag reduction rate of20ppm PAM was only14.71%; The influence of gravity on drag reduction performance of high molecular polymers DRA can be ignored; Shear degradation were a main factor in the failure of polymer DRA degradation, when DRA brine was cut by centrifugal pump, drag reduction disappeared in a very short period of time.4The drag reduction rate variation with concentration of PEO was similar to PAM, but Re has less effects on the drag reduction rate, at normal temperature, the drag reduction rate of PEO in clear water also can reach more than50%; temperature has larger influence on the PEO drag reduction performance, the drag reduction rate of PEO fell sharply as the temperature increases; Compared with PAM, PEO was not sensitive to salinity, drag reduction performance is better than that of PAM in normal brine; The combination of temperature and salinity has great effect on the drag reduction performance of PEO, drag reduction is almost lost in40℃brine.5Fourier transform infrared spectrometry was employed to analyze modified products of PAM, the results showed that the reaction product had obvious characteristic peak, indicating the occurrence of the hydrolysis reaction and sulfomethylation; Hydrolysis reaction had a little effects on the drag reduction effect, and the heat resistance and salt resistance of HPAM reduced than PAM; Sulfomethylation could improve the drag reduction performance significantly, especially in the improvement of heat resistance and salt resistance, when the concentration of SPAM was20PPM, the drag reduction rate could be increased by19percentage points to33%.Through a comprehensive comparison of drag reduction performance of various types of DRA, the kind of DRA that most optimized for drag reduction in mining transport bittern process was SPAM, the drag reduction performance of PAM and HP AM was poor; PEO had no drag reduction in high temperature brines.