The Geochemical Study Of Coal-generated Hydrocarbon In Simulated Experiment

Kuche depression is regarded as a good region to prospect coal generating hydrocarbon in Talimu basin in order to provide gases in plenty for 揥est gases transporting to East region ? The maturity of coal organic matters is higher, because Kuche depression suffered from several tectonic movements. However the depositional environment of Manjia抏r depression was similar to Kuche depression, and the maturity of its coal is low (Ro0.4%), so the coal was regarded as the character of coal generating hydrocarbon in Kuche depression. Thus, we study marceral forming hydrocarbon so that it can provide the valid potentialities of coal generating gas and its evolution.In order to get a reliable rates of gas products by simulating coal rock and its marceral in different temperatures, we used the methods of large sample quantity, metal seal, gas collected in minus pressure. Thus it improved the measurable precision of gas and relieved gas leakage that caused isotopic fractionation.The results showed the rates of gas products are increased while the temperature goes up through the thermal simulation to 7 series of original coal rocks of Talimu basin in Jurassic system and its marceral heated individually from 250 ~C to 5500C, which the temperature stage is 500C ;but the rate of individual series is different each other. The gas product rate of exinite is highest than another rates and it is 244.8 8mlIgTOC, however the gas product rate of semifusinite is lowest and 84.14m1/gTOC.there are two stages of generating hydrocarbon in coal rock added distilled water (2g rock lml distilled water). Except exinite and vitrinite, the rates of heavy hydrocarbon are low for another matters. But the abundance of heavy hydrocarbon becomes high and remains long due to added water to coal rock. Carbondioxide and Nitrogen are higher in proportion to the vessel in the low temperature.Ratios of alkane and acid are increased while the temperature goes up. And the desiccant factors are rising with the temperature going up and go though the dry- damp- dry process, but this character will be changed with water added. The products of Heavy hydrocarbon are correlated with not only temperature but also marceral. And the heavy hydrocarbons mainly derive from exinite and vitrinite, whereas they can be added with the water added under high temperature.It shows that stable carbon isotope becomes heavy with evolution of coal organic matter by measured the stable carbon isotope of simulated gases. The datum of The 8?C~0 are presented in our paper and the significance of these findings that The 8?C~114 may become more heavy with the influence of the 魭3C~0 is illustrated due to the stacking of both the peak of 8?C~14 and the peak of 8?C~0 in the measurement of MAT25 1. Then the correlation of CH4~ CO2 and CO is following:~l3c1 << &3cc02There are two stages of liquid hydrocarbon generated while the temperature rises gradually from 250 0C to 550 0C .One peak rang of forming hydrocarbon is 350C-400C;the other is above 550C. The liquid hydrocarbon product rate of exinite is highest than another rates and it is 260.80m1/g, however the product rate of inertinite is lowest, only 2.30m1/g. The character of vitrinite is that the liquid hydrocarbons are forming early and the gas is the major product.By analyzing the gas, liquid hydrocarbon and remnant, the results is illustrated that the abundance of vitrinite isivSemphasized and that of exinite is important too in the assessment of coal generating gases. However in the assessment of coal generating liquid hydrocarbon, the abundance of exinite is the key.All the results are helpfiul for people to understand the characteristic evolution of hydrocarbon rocks generating gas and liquid hydrocarbon from organic-catalytic transient belt gas to cracking gas in Kuche depression, Talimu. Moreover, these data will also favor the prospect of petroleum and gas, which showed a great potential in hydrocarbon production.