Supercritical CO2 fracking for enhanced shale gas recovery and CO2 sequestration: Results, status and future challenges

 Supercritical carbon dioxide(ScCO2)-based fracturing technology associating with CO2 enhanced shale gas recovery is a promising technology to reduce the water consumption of shale gas production and could provide the potential for CO2 sequestration. Advancing the understanding of complex gas shale reservoir behavior in the presence ofmultiphase and multicomponent gases (ScCO2, gaseous CO2 and CH4 etc.) via laboratory experiments, theoretical model development and field validation studies is very important. In this paper, the progress of some key scientific problems such as the mechanism of ScCO2 drilling and completion, the ScCO2 fracturing technology, the competition adsorption behaviors of CO2/CH4 in shale, the coupled multiphase and multicomponent CO2/CH4 flow during the CO2 enhanced shale gas recovery process and the CO2 sequestration potential in shale formation were discussed. Finally, the challenges of the technique will face and the further research is needed in the future is also exposed.Cited as: Zhou, J., Hu, N., Xian, X., Zhou, L., Tang, J., Kang, Y., Wang, H. Supercritical CO2 fracking for enhanced shale gas recovery and CO2 sequestration: Results, status and future challenges. Advances in Geo-Energy Research, 2019, 3(2): 207-224, doi: 10.26804/ager.2019.02.1

Supercritical CO2 fracking for enhanced shale gas recovery and CO2 sequestration: results, status and future challenges

Supercritical carbon dioxide(ScCO2)-based fracturing technology associating with CO2 enhanced shale gas recovery is a promising technology to reduce the water consumption of shale gas production and could provide the potential for CO2 sequestration. Advancing the understanding of complex gas shale reservoir behavior in the presence ofmultiphase and multicomponent gases (ScCO2, gaseous CO2 and CH4 etc.) via laboratory experiments, theoretical model development and field validation studies is very important. In this paper, the progress of some key scientific problems such as the mechanism of SCCO2 drilling and completion, the ScCO2 fracturing technology, the competition adsorption behaviors of CO2/CH4 in shale, the coupled multiphase and multicomponent CO2/CH4 flow during the CO2 enhanced shale gas recovery process and the CO2 sequestration potential in shale formation were discussed. Finally, the challenges of the technique will face and the further research is needed in the future is also exposed

Effect of Peripheral Administration of Kisspeptin-10 on Dynamic LH Secretion in Prepubertal Ewes

The aim of the present study was to clarify the effect of kisspeptin-10 on LH secretion in prepubertal ewes. In experiment 1, prepubertal ewes fitted with indwelling jugular catheters were randomly assigned to receive 0, 0.5, 1 or 2 mg of kisspeptin-10 dissolved in saline, and serial blood samples were collected at 15-min intervals for 180 min to analyze the response curves of LH after injection. In experiment 2, prepubertal ewes fitted with indwelling jugular catheters were injected with 0 or 1 mg of kisspeptin-10 dissolved in saline and the injection was repeated 3 times at 1 h interval and serial blood samples were collected at 15-min intervals for 210 min to analyze the response curves of LH after injection. The results showed that single intravenous administration of 0.5, 1 and 2 mg of kisspeptin-10 all could significantly increased LH secretion in prepubertal ewes, and the effect of 1 and 2 mg of kisspeptin-10 on LH secretion was higher than that of 0.5 mg group. The results also showed that repeated intravenous administration of kisspeptin-10 could effectively increase LH secretion and repeated administration did not influence the effect of kisspeptin-10 on LH secretion in prepubertal ewe. In conclusion, the present study indicated that single or repeated intravenous administration of kisspeptin-10 could effectively increase LH secretion in prepubertal ewes

The Average IFN- γ

Previous studies suggested that both the frequency and the mean fluorescence intensity (MFI) of cytokine secreting T cells could be of great value for immunogenicity evaluation of a vaccine. In this study, by constructing epitope-based DNA vaccines encoding a previously identified CD8+ T cell epitope, we investigated the influence of multiplying epitope copies on both the frequency and the MFI of specific IFN-γ secreting CD8+ T cells. We found that frequencies of specific CD8+ T cell could be improved by multiplying epitope copies, while the MFI of IFN-γ secreted by epitope-specific CD8+ T cells decreased synchronously. And further analysis showed that the decrease of MFI was not caused by the functional avidity variation of CD8+ T cell receptor

Screening for Anti-Inflammation Quality Markers of Lianhua Qingwen Capsule Based on Network Pharmacology, UPLC, and Biological Activity

Influenza is a common respiratory infectious disease. In China, Lianhua Qingwen capsule (LHQWC), a drug with significant clinical efficacy and few side effects, is commonly used to treat influenza. However, the composition of LHQWC is complicated, and currently used quality control methods cannot ensure its consistency. In this study, combined with its clinical efficacy, the targets of LHQWC were screened using network pharmacology. Then, anti-inflammation quality markers of LHQWC were screened and judged by combined chemical with biological evaluation. Cyclooxygenase-2 (COX-2) was identified as one of the main targets of the anti-inflammatory activity of LHQWC. The rate of inhibition of COX-2 by different batches of LHQWC was determined. Furthermore, seven components of LHQWC were identified. The potential quality markers were screened by spectral-effect relationship. As a result, chlorogenic acid, isochlorogenic acid B, and isochlorogenic acid C were identified and confirmed as anti-inflammatory quality markers of LHQWC. We hope that these findings provide a scientific basis for the accurate quality control of LHQWC and serve as a reference for the quality control of other drugs

Modelling and simulation of the urban heat island effect in a tropical seaside city considering multiple street canyons

For tropical seaside cities, the net advection heat flux plays a significant role in local urban heat island (UHI) formation during the nocturnal time. However, the net advection heat flux is usually neglected in conventional modelling methods. An improved urban canopy model (UCM) has been developed to simulate the UHI effect in the tropical seaside cities. The model was proposed by introducing an adaptive approach to estimate the airflow rate inside a street canyon. Furthermore, the airflows in multiple connected street canyons were also considered. The improvements of the proposed model were validated with experiments conducted in a typical tropical seaside city, Sanya, China. In summer, the maximum error between the measured data and the simulation result of the conventional model was 0.68°C, which was reduced to 0.21°C with the proposed model. In winter, the maximum error was reduced from 0.84°C with the conventional model to 0.49°C with the proposed model. The experimental studies also showed that the UHI in summer (0.5–1.1°C) was greater than that in winter (0.4–0.5°C). On summer nights, wind flow along the streets had a greater mitigation effect on UHI formation than that in the daytime. </jats:p

The Improved Model of the Deep Peak Regulation Market Considering the Load Aggregator Participation

Abstract Severe load valley brings lots of difficulties to the system operation. The thermal generators undertake the deep peak regulation for valley filling traditionally when they are the main source of the generation. As the renewable energy develops quickly, the thermal generation keeps reducing in recent years. Most of the provinces in China chose to develop deep peak regulation market before a complete spot market. The current participants mainly include the thermal generators and the storages. In this paper, the load aggregator is proposed as the participants of the market to increase the load at the load valley. The operators clear the market with the co-optimization including both of the generators and the aggregators. The simulation has demonstrated the operation of the market model.</jats:p