The reservoir pore structure controls the reservoir quality and resistivity response of hydrocarbon-bearing zones and thus, critically affects logging interpretation. We use petrophysical data in three types of reserv...The reservoir pore structure controls the reservoir quality and resistivity response of hydrocarbon-bearing zones and thus, critically affects logging interpretation. We use petrophysical data in three types of reservoir with different pore structure characteristics to show that the complexity of pore structure had a significant effect on the effective porosity and permeability regardless of geological factors responsible for the formation of pore structure. Moreover,, the distribution and content of conductive fluids in the reservoir varies dramatically owing to pore structure differences, which also induces resistivity variations in reservoir rocks. Hence, the origin of low-resistivity hydrocarbon-bearing zones, except for those with conductive matrix and mud filtrate invasion, is attributed to the complexity of the pore structures. Consequently, reservoir-specific evaluation models, parameters, and criteria should be chosen for resistivity log interpretation to make a reliable evaluation of reservoir quality and fluids.展开更多
At Olkaria （Kenya） geothermal energy has been used since 1981, to generate electricity and now there are currently 3 plants with a nominal capacity of 205 MW. Preliminary measurement and evaluation of possible mercu...At Olkaria （Kenya） geothermal energy has been used since 1981, to generate electricity and now there are currently 3 plants with a nominal capacity of 205 MW. Preliminary measurement and evaluation of possible mercury （Hg） emission from two plants has been investigated. Potential atmospheric Hg emission has been determined based on an existing model for estimating the transport of mercury along geothermal fluid flow streams as pertains to energy recovery and conversion from liquid dominated geothermal reservoirs. Hg concentrations, addition, retention and release rates were calculated at a number of locations in the geothermal power plants based on the plant operating parameters and steam flow process （turbine, condenser, non-condensable gas ejector, and cooling tower）. Potential Hg emission rates through plume range from 0.455 g/h to 2.17 g/h, or 10-30 mg/h per MWe. The emission per hour per MWe is 130-300 times lower compared to Hg levels reported for 88 MWe five operating geothermal power plants around Mt. Amiata area in Italy. These emissions are coupled with a release of 1.07 kg/h per MW of hydrogen sulphide （HzS）. The potential Hg release rates to the environment will depend greatly on the concentration of HzS in the system. Any higher HzS contents may reduce solubility of rig in the brine hence making it to be available in the steam. The volatile Hg may travel with the non-condensable gases as Hg vapour.展开更多
China has a large potential to reduce CO2 emission in the Asian region. In this study, life cycle analyses of energy supply technologies in China were evaluated for enforcing the clean development mechanism （CDM）. W...China has a large potential to reduce CO2 emission in the Asian region. In this study, life cycle analyses of energy supply technologies in China were evaluated for enforcing the clean development mechanism （CDM）. Wind power, integrated coal gasification combined cycle （IGCC）, natural gas combined cycle （NGCC）, and ultra super critical power plant （USC） were chosen as new power generation technologies. The system function of the developed model was enhanced to extend coverage to new technologies for power generation systems in China. CO2 intensities, energy profit ratios, and CO2 emission reductions are estimated based on the assumption that these power plants were constructed at Shanxi, Xinjiang, and Shanghai. Wind power showed the best results with regard to CO2 intensity and energy profit ratio. However, it also has some disadvantages with regard to the utilization factor and the lifetime. It is considered that wind power will become an important part of CDM activities as the utilization factor and the lifetime improve. An NGCC using a natural gas pipeline was found to be most advantageous in reducing CO2 emission. IGCC and USC were inferior to NGCC with regard to energy profit ratios and CO2 emission reductions.展开更多
基金supported by China national petroleum corporation science and technology development projects(No.2011D_4101)
文摘The reservoir pore structure controls the reservoir quality and resistivity response of hydrocarbon-bearing zones and thus, critically affects logging interpretation. We use petrophysical data in three types of reservoir with different pore structure characteristics to show that the complexity of pore structure had a significant effect on the effective porosity and permeability regardless of geological factors responsible for the formation of pore structure. Moreover,, the distribution and content of conductive fluids in the reservoir varies dramatically owing to pore structure differences, which also induces resistivity variations in reservoir rocks. Hence, the origin of low-resistivity hydrocarbon-bearing zones, except for those with conductive matrix and mud filtrate invasion, is attributed to the complexity of the pore structures. Consequently, reservoir-specific evaluation models, parameters, and criteria should be chosen for resistivity log interpretation to make a reliable evaluation of reservoir quality and fluids.
文摘At Olkaria （Kenya） geothermal energy has been used since 1981, to generate electricity and now there are currently 3 plants with a nominal capacity of 205 MW. Preliminary measurement and evaluation of possible mercury （Hg） emission from two plants has been investigated. Potential atmospheric Hg emission has been determined based on an existing model for estimating the transport of mercury along geothermal fluid flow streams as pertains to energy recovery and conversion from liquid dominated geothermal reservoirs. Hg concentrations, addition, retention and release rates were calculated at a number of locations in the geothermal power plants based on the plant operating parameters and steam flow process （turbine, condenser, non-condensable gas ejector, and cooling tower）. Potential Hg emission rates through plume range from 0.455 g/h to 2.17 g/h, or 10-30 mg/h per MWe. The emission per hour per MWe is 130-300 times lower compared to Hg levels reported for 88 MWe five operating geothermal power plants around Mt. Amiata area in Italy. These emissions are coupled with a release of 1.07 kg/h per MW of hydrogen sulphide （HzS）. The potential Hg release rates to the environment will depend greatly on the concentration of HzS in the system. Any higher HzS contents may reduce solubility of rig in the brine hence making it to be available in the steam. The volatile Hg may travel with the non-condensable gases as Hg vapour.
文摘China has a large potential to reduce CO2 emission in the Asian region. In this study, life cycle analyses of energy supply technologies in China were evaluated for enforcing the clean development mechanism （CDM）. Wind power, integrated coal gasification combined cycle （IGCC）, natural gas combined cycle （NGCC）, and ultra super critical power plant （USC） were chosen as new power generation technologies. The system function of the developed model was enhanced to extend coverage to new technologies for power generation systems in China. CO2 intensities, energy profit ratios, and CO2 emission reductions are estimated based on the assumption that these power plants were constructed at Shanxi, Xinjiang, and Shanghai. Wind power showed the best results with regard to CO2 intensity and energy profit ratio. However, it also has some disadvantages with regard to the utilization factor and the lifetime. It is considered that wind power will become an important part of CDM activities as the utilization factor and the lifetime improve. An NGCC using a natural gas pipeline was found to be most advantageous in reducing CO2 emission. IGCC and USC were inferior to NGCC with regard to energy profit ratios and CO2 emission reductions.
