Synthesis and atomization gas DRA drag reduction performance testing device design
|Keywords||DRA gas pipeline Oligomers Atomization performance Reduction in Atomizing device|
Due to changes in the structure of the world's energy, natural gas will play an increasingly important role in the international energy structure. At present, the main mode of transport of natural gas pipeline transportation, with the world on the development of natural gas this high-quality clean energy and fuel demand growing and a large number of remote gas fields, the world of long gas pipeline has been developing rapidly, long distance gas technology greatly improved, the Long Distance big diameter and high-pressure pipeline is the mainstream of the development of natural gas pipeline in the world today. Gas pipeline transportation, the pressure loss of the gas in the pipeline is an issue to be considered. Gas pipeline transportation, the pressure loss of the gas in the pipeline is an issue to be considered. When the gas in the turbulent area, especially at high Reynolds number zone, the pressure loss caused by the presence of gas energy loss due to turbulence and other random movement larger and more wall roughness is caused by the eddy current. Therefore used to reduce the roughness of the gas pipeline to reduce the pressure loss of the primary means to increase the gas transmission flow. Present, commonly used pipe coating drag reduction technology to reduce wall roughness and achieved good effects and good economic benefits, but the pipe coating drag reduction technology complex construction equipment, higher costs and over time extend the original non-coated pipes at the same time, due to construction costs and other issues, can not be applied to the real inner coating off the drag reduction effect is gradually reduced and even produce negative effects. Injected directly into the gas DRA proposed drag reduction technology for pipe coating; another type of method, which has broad application prospects. In the 1990s, the United States took the lead in the DRA natural gas drag reduction technology research and actual gas pipeline application experiment achieved initial results. The technique is called gas DRA having surfactant properties chemicals periodically injected into the natural gas pipeline through the adsorption of the polar ends on the steel surface, elastic molecular film is formed, to reduce the wall roughness to achieve drag reduction purposes. This paper reviews the technology status and trends in the development of domestic and international natural gas pipeline, gas pipeline coating drag reduction technology, DRA drag reduction technology and pipeline filling process analyzes, drag reduction on natural gas and DRA technology research the meaning and the problems that may exist. The DRA drag reduction technology, summarized the gas DRA Drag Reduction Mechanism should be pointed out that the main substance of the weather DRA has a similar structure of the surfactant, polar and non-polar groups, polarity adhesion of one end of the group be provided on the inner wall of the conduit, one end of the non-polar group in the gas - solid interface is formed between the wall and the flowing gas, and the substance is preferably a gas or atomized liquid, a sufficiently small diameter molecules , can enter or fill the \Gas pipeline corrosion inhibitors, antifreeze filling process research DRA filling process, establish and improve the drag reduction performance testing device and DRA have important implications in the field application. According to the gas DRA Drag Reduction Mechanism designed and synthesized five drag reduction potential, easy atomized oligomer: heterocyclic oligomer I heterocyclic oligomer II, the heterocyclic oligomer III Low homo Ⅳ, oligomer Ⅴ. The characterization of the desired product of the synthesis of the infrared spectra, and analyzed by infrared tracking Reaction optimization experiments are discussed in detail the influence of various reaction conditions on the oligomer, gives optimum synthesis conditions. The selection of an appropriate solvent were prepared five oligomer in the steel surface of the adsorption film and observed by SEM techniques five compounds the steel sheet surface film, they significantly reduce the roughness of the steel surface of the original, the potential reduction resistance performance. Compared with the research group pre-synthetic products, the oligomer has the advantage of easily atomized. DRA fully atomized droplets smaller in diameter and uniform, easily carried by natural gas, and rely on natural gas turbulent diffusion and evenly smear \Therefore, in the apparatus on the basis of the performance testing of the original gas DRA, preliminary design the test device of the drag reduction efficiency of the atomizing device, and atomizing gas DRA. Operation process becomes: the original film forming apparatus, the the experimental pipe inner surface of the cleaning process; after experimental pipe installation to the ring road testing apparatus, after the determination of drag reduction efficiency of the injected through gas atomization apparatus deposition. Throughout the design part of the design purpose, design ideas, parameter selection method, operating conditions, and to lay the foundation for the practical application of the study evaluation and even natural gas DRA gas DRA.