Research On Hydrocarbon Quantitative Separation And Detection Method Of Drilling Fluids

The logging while drilling techniques of oil and gas helps to test and evaluate the conditions of the underground oil and gas, which have contributed to discover, evaluate and interpret the oil and gas zones. At present the degasser is the key way using in oil-gas separation while drilling. The chromatography is used to separate the alkane from the drilling fluids and then test and evaluate. The existing problems such as non-standard detection methods, slow analysis speed and non-quantitative oil-gas evaluation, constrain the development and promotion of the technology.Through analyzing the existing problems in gas detection while drilling, it starts with the degassing and testing, promotes a set of quantitative oil and gas detection methods, and develops an integrated prototype system.It proposes a new method of quantitative drilling fluid during the degassing process. The idea of a semipermeable membrane degassing is introduced by analyzing the migrational mode of the gas circulation of the drilling fluid, and a new type of oil and gas separation unit which can takes samples by directly inserting into the drilling fluid is designed.During the oil-gas detection, it analyzes the fast chromatographic techniques, systematically summarizes the method of increasing the speed of gas detection. Starting from optimizing the minimum resolution, selecting the chromatographic column and working parameters, it defines the factor of the various factors affecting the speed of gas detection. Based on the experimental research, it proposes a set of quick oil and gas detection device on the basis of TCD, which expands the range of oil-gas detection from C1~C5 to C1~C8(including benzene and methylbenzene). The analysis cycle of the detection system is 90 s.In the evaluation of oil and gas, it proposes the method of identification of small signal aimed at the problem of tiny signal, the contrasting approaches of gas logging values in different wells in consideration of different mud logging systems, the recognition method of response of the mixed oil gas logging aimed at interference problem of the mixed oil drilling fluid.After laboratory experiment and field test in two wells, the detecting system is proved to be reasonable, good quantitative of degassing, available ingredients and high speed acquisition. This may provides a new means for oil and gas testing in drilling filed.