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51.
Investigating adsorption of methyl parathion on the activated carbons Filtrasorb 400 and F 44 and on the adsorption polymer Wofatit Y 77 we found a stronger adsorption on the carbons at smaller concentration whereas the resin has the larger capacity at higher concentration. Adsorbents were regenerated through hydrolysis of the pesticide at pH = 11.7. The velocity of hydrolysis in the adsorbed state is reduced to a tenth of that in solution. However, a transport resistance in the pores of adsorbents seems to be negligible as may be concluded from the very small measured particle diameter dependence of the velocity constants. In adsorption-regeneration measurements the capacity of the adsorbents stabilized at about 70% of that of the fresh adsorbents. 相似文献
52.
Kinetic study of the hydrocarbon generation from Upper Paleozoic coals in Ordos Basin 总被引:6,自引:0,他引:6
When organic matter during geological processes is affected by a variety of factors such as paleotemperature, and time, complicated chemical reactions will occur, finally resulting in the generation of petroleum and natural gas. These reactions leading to… 相似文献
53.
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been applied to determine the elemental composition of the surface layer, as well as of the first interior layer, of quartz grains from the mine tailings from Kristineberg (northern Sweden) in order to determine concentration gradients between these two layers. The quartz grains were collected from the oxidized and unoxidized zones within the tailings. The aim of this study is to assess the role of quartz surfaces as sites for the attenuation of solutes from the mine-tailings porewater. Concentrations of Cu, Ag, Sb, Pb and Bi are highest near the surface of each grain and decrease towards the interior. The surface concentration of Cu, Zn and Pb is more pronounced within the unoxidized than within the oxidized zone of the tailings. Cu exhibits a distinct concentration peak at the surface of the quartz grains below the pre-remediation oxidation front. For Zn and Ce the trend of high surface concentration is less pronounced than for Cu or Pb. Silver, Bi and As are preferably adsorbed within the uppermost layers of the oxidized zone where the pH is as high as 6.2. The conversion of intensity signals of the elements to concentration values in ppm was done by using external standards (NIST silicate glass). 相似文献
54.
二连盆地侏罗系地层热演化史研究 总被引:5,自引:1,他引:4
本文应用磷灰石裂变径迹,镜质体动力学模型等方法恢复二连盆地侏罗系地层的热演化史,二连盆地图参1井磷灰石退火浓度为1600-2774m,对应的退火温度为64-102.7℃,图参1井现今温度小于最高古地温,这是由于二连盆地地温梯度逐渐降低及地层发生抬升和剥蚀所致。根据磷灰石裂变径迹分析和镜质体动力学模型模拟图参1井的热演化史,在晚侏罗世时其经受的最高地温梯度分别为7℃/hm和6℃/hm。侏罗系地层在晚 相似文献
55.
Geochemical studies of shale gas and conventional reservoirs within the Triassic Yanchang Formation of Xiasiwan and Yongning Field, Ordos Basin show that methane is isotopically depleted in 13C as compared to δ13C1 calculated by the Ro based on the relationship between δ13C1 and Ro. Geochemical fractionation during the adsorption/desorption process of shale system may play a significant part in influencing δ13C1 values of shale gas. Two shale core samples from confined coring of the Yanchang Formation were adopted segmented desorption experiments to examine this phenomenon. The results show that the δ13C1 of desorbed gas changes little in the first few phases of the experiments at low desorption levels, but become less negative rapidly when the fraction of desorbed methane exceeds 85%. The desorption process for the last 15% fraction of the methane from the shale samples shows a wide variation in δ13C1 from −49‰ to −33.9‰. Moreover, δ13C1 of all desorbed methane from the shale samples is substantially depleted in 13C than that calculated by Ro, according to Stahl and Carey's δ13C1–Ro equation for natural gas generated from sapropelic organic matter. This shows some gases with isotopically enriched in 13C cannot be desorbed under the temperature and pressure conditions of the desorption experiments. This observation may be the real reason for the δ13C1 of shale gases and conventional reservoirs becomes more negative in Xiasiwan and Yongning Fields, Ordos Basin. The magnitude of the deviation between the δ13C1 of shale gas and that calculated by Ro may be related to the adsorption capacity of shale or the proportion of absorbed gases. In this way, we may be able to evaluate the relative adsorption capacity of shale in geological conditions by δ13C1 of the shale gas, or by δ13C1 of conventional gas which generated by the shale with certainty. The δ13C1 of conventional gas in Dingbian and Yingwang Fields have no deviation because the TOC value of the hydrocarbon source rock is relatively low. 相似文献
56.
Abstract We carried out hydrothermal experiments in the system dolomite‐quartz‐H2O to track the temporal change in reaction rates of simultaneous reactions during the development of reaction zones. Two types of configurations for the starting materials were prepared: dolomite single crystals + quartz powder + water and quartz single crystals + dolomite powder + water, both sealed separately in gold capsules. Runs at 0.1GPa and 600°C with cold seal pressure vessels gave the following results. (i) In short duration (45–71 h) runs metastable layer sequences involving wollastonite and talc occur in the reaction zone, whereas they disappear in longer duration (168–336 h) runs. (ii) The layer sequence of the reaction zones in short duration runs differs from place to place on the dolomite crystal even in the same run. (iii) The diversity of layer sequences in the short duration runs merges into a unique layer sequence in the longer duration runs. (iv) The reaction zone develops locally on the dolomite crystal, but no reaction zone was observed on the quartz crystal in any of the runs. The lines of evidence (i)–(iii) show that the system evolves from an initial transient‐ to a steady‐state and that the kinetic effect is important in the development of reaction zones. A steady diffusion model for the unique layer sequence Qtz/Di/Fo + Cal/Dol + Cal/Dol shows that the Dol + Cal layer cannot be formed by diffusion‐controlled process and that the stability of the layer sequence Qtz/Di/Fo + Cal/Dol depends not only on L‐ratios (a = /LCaOCaO and b = /LMgOMgO) but also on the relative rate P = (−2ξ1 − ξ2)/(–ξ1 − 2ξ2) of competing reactions: Dol + 2Qtz = Di + 2CO2 (ξ1) and 2Dol + Qtz = Fo + 2Cal + 2CO2 (ξ2). For smaller P the stability field will shift to higher values of a and b. The steady diffusion model also shows that the apparent‐non‐reactivity on the quartz surface can be attributed to void formation in a large volume fraction in the diopside layer. 相似文献
57.
There has been a revival in hydrocarbon source rock characterization and development associated with growing interest in unconventional resources, where these fine-grained organic-rich rocks act as both source and reservoir. To-date, the exploration focus on shale reservoirs has been largely on marine systems. Lacustrine source rocks for conventional resources are geographically important, dominating regions such as China, Indonesia, and Brazil's resource-base. However, they have been generally untested for unconventional resources.There are a number of key differences in the nature of these hydrocarbon systems that should be considered when assessing whether lacustrine systems may represent future unconventional opportunities in areas where the conventional resource-base is dominated by lacustrine-sourced oil. Among the key differences between these depositional systems is the greater sensitivity to high frequency climatic variability within lacustrine systems. Lacustrine systems are highly sensitive to changes in the balance between precipitation and evaporation, which may lead to rapid changes in lake level, potentially exceeding 600 m. These changes in depositional conditions are geologically rapid and may occur over periods of thousands of years. Such changes can reduce the areal extent of potentially thick source rock intervals to only those portions of a basin where a permanent deep lake was present. Thus the core unconventional target area may be geographically limited compared with their marine counterpart. Although potentially areally limited, a review of many lacustrine source rocks suggests that their thicknesses are often significantly greater than marine source rocks. An examination of the more distal portions of lacustrine systems, where better source rock potential is present reveals that there is generally limited connectivity between source and conventional reservoir. In these settings, such as the Wind River basin (Waltman Shale), the hydrocarbons remain trapped within the shales, potentially leading to over-pressured hydrocarbon charged systems. Such conditions suggest that although areally limited, viable unconventional targets may exist, if suitable reservoir conditions are present. Finally, the character of the oils produced is different in these settings, with lacustrine oils being waxy and displaying different hydrocarbon generation and cracking kinetics. High wax oils display distinct flow characteristics, being more viscous, and may offer different production challenges than their non-waxy marine equivalents. Additionally, differences in their cracking kinetics may indicate that the timing of gas generation for shale gas plays may differ significantly from marine systems. 相似文献
58.
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60.
正1 Introduction The Pingluoba brine,which characterized as high concentration with sodium,potassium,boron,lithium,and rubidium,possess great development value.The main composition of the brine can be summarized to the 相似文献