The supercritical water gasification of phenolic wastewater without oxidant was performed to degrade pollutants and produce hydrogen-enriched gases. The simulated o-cresol wastewater was gasified at 440-650℃ and 27.6...The supercritical water gasification of phenolic wastewater without oxidant was performed to degrade pollutants and produce hydrogen-enriched gases. The simulated o-cresol wastewater was gasified at 440-650℃ and 27.6 MPa in a continuous Inconel 625 reactor with the residence time of 0.42-1.25 min. The influence of the reaction temperature, residence time, pressure, catalyst, oxidant and the pollutant concentration on the gasification efficiency was investigated. Higher temperature and longer residence time enhanced the o-cresol gasification. The TOC removal rate and hydrogen gasification rate were 90.6% and 194.6%, respectively, at the temperature of 650℃ and the residence time of 0.83 min. The product gas was mainly composed of H2, CO2, CFL and CO, among which the total molar percentage of H2 and CFL was higher than 50%. The gasification efficiency decreased with the pollutant concentration increasing. Both the catalyst and oxidant could accelerate the hydrocarbon gasification at a lower reaction temperature, in which the catalyst promoted H2 production and the oxidant enhanced CO2 generation. The intermediates of liquid effluents were analyzed and phenol was found to be the main composition. The results indicate that the supercritical gasification is a promising way for the treatment of hazardous organic wastewater.展开更多
Shale gas reservoirs are unconventional tight gas reservoirs,in which horizontal wells and hydraulic fracturing are required to achieve commercial development.The fracture networks created by hydraulic fracturing can ...Shale gas reservoirs are unconventional tight gas reservoirs,in which horizontal wells and hydraulic fracturing are required to achieve commercial development.The fracture networks created by hydraulic fracturing can increase the drainage area extensively to enhance shale gas recovery.However,large volumes of fracturing fluid that is difficult to flow back to the surface and remained in the shale formation,will inevitably lead to damages of the shale formations and limit the effectiveness of stimulation.Supercritical water(SCW)treatment after hydraulic fracturing is a new method to enhance shale gas recovery by using appropriate heat treatment methods to the specific formation to convert the retained fracturing fluid into a supercritical state(at temperatures in excess of 373.946°C and pressures in excess of 22.064 MPa).An experiment was conducted to simulate the reaction between shale and SCW,and the capacity of SCW treatment to enhance the permeability of the shale was evaluated by measuring the response of the shale porosity and permeability on SCW treatment.The experimental results show that the shale porosity and permeability increase by 213.43%and 2198.37%,respectively.The pore structure alteration and permeability enhancement of the shale matrix were determined by analyzing the changes in pore structure and mineral composition after SCW treatment.The mechanisms that affect pore structure and mineral composition include oxidative catalysis decomposition of organic matters and reducing minerals,acid-catalyzed decomposition of carbonate minerals and feldspar minerals,hydrothermal catalysis induced fracture extension and cementation weakening induced fracture extension.SCW treatment converts harm into a benefit by reducing the intrusion of harmful substances into the shale formation,which will broaden the scope and scale of shale formation stimulation.展开更多
Large volumes of water are generated in gas- and oil-production. This includes the water that is present originally in the reservoirs, but also water that is injected into the wells. While currently much of the produc...Large volumes of water are generated in gas- and oil-production. This includes the water that is present originally in the reservoirs, but also water that is injected into the wells. While currently much of the produced water is either reinjected or disposed of after treatment, treated produced water is increasingly seen as an interesting resource, especially in water-scarce regions. This review looks at different PW treatment methods available, with an emphasis on the management of PW in oil- and gas production on the Arabian Peninsula.展开更多
The most important waste stream created during oil and gas production is oilfield-produced water.When discharged without treatment,it poses a significant risk of pollution of marine ecosystems.While adequate treatment...The most important waste stream created during oil and gas production is oilfield-produced water.When discharged without treatment,it poses a significant risk of pollution of marine ecosystems.While adequate treatment before disposal is acceptable,achieving authorized discharge criteria continues to be a problem for the petroleum sector.This research examined the physicochemical characteristics of produced water at various month intervals before and after treatment.Heavy metal and organic component concentrations in water samples were determined using atomic absorption spectroscopy and gas chromatography.The results indicate that produced water from a certain Niger Delta oilfield contains significant amounts of heavy metals and some organic compounds after treatment.The present laws,as well as the measurement of dispersed oil and grease content,have been in place for a long period of time without considerable change,even though most dangerous components in produced water are dissolved.It is recommendable for the prospective field developers/operators to consider the dissolved components of produced water and consider the economic consequences of adopting tertiary produced water polishing technologies.展开更多
Membrane technology has become one of the most promising separation technologies for its energy saving, high separation efficiency, environmental friendliness, and economic feasibility. Covalent organic frameworks(COF...Membrane technology has become one of the most promising separation technologies for its energy saving, high separation efficiency, environmental friendliness, and economic feasibility. Covalent organic frameworks(COFs) with intrinsically high porosity, controllable pore size, uniform pore size distribution and long-range ordered channel structure, have emerged as next-generation materials to fabricate advanced separation membranes. This feature article summarizes some latest studies in the development of pure COF membranes in our lab, including their fabrication and applications in chemical separations. Finally, current challenges facing high-performance COF separation membranes are discussed.展开更多
Biogas is a significant renewable source as well as an alternative energy carrier provided by Anaerobic Digestion(AD)of biodegradable food wastes and other organic materials.This paper describes some major facts about...Biogas is a significant renewable source as well as an alternative energy carrier provided by Anaerobic Digestion(AD)of biodegradable food wastes and other organic materials.This paper describes some major facts about biogas along with the barriers and adaptation of CBG in society,it also narrates the types of feedstocks available for biogas generation and what are the major sources in India.In this study,different stages of anaerobic digestion are discussed such as hydrolysis,acidogenesis,acetogenesis and methanogenesis for biogas production.After its purification,the biogas can be used as a fuel for domestic as well as transportation purposes.A glimpse of biogas like purification techniques like biological desulphurization,iron chloride dosing,pressure swing adsorption,chemical scrubbing and water scrubbing is given,the major additions of national policy of biofuels in 2018 is also highlighted.It has been found that in India,majorly pressure swing adsorption and water scrubbing methods are used for biogas purification,currently,the country has 12 commercial CBG plants with a total CBG output capacity of 18,461.7 tonnes per year,which is just 0.06 percent of the total ability.The details of the plants along with their CBG production capacity are described,and sustainable alternative towards affordable transportation(SATAT)launched by MoPNG is introduced in this study,furthermore,the features and types of models suggested by Ministry of Petroleum and Natural Gas(MoPNG)to introduce compressed biogas(CBG)in city gas distribution(CGD)network are discussed.展开更多
文摘The supercritical water gasification of phenolic wastewater without oxidant was performed to degrade pollutants and produce hydrogen-enriched gases. The simulated o-cresol wastewater was gasified at 440-650℃ and 27.6 MPa in a continuous Inconel 625 reactor with the residence time of 0.42-1.25 min. The influence of the reaction temperature, residence time, pressure, catalyst, oxidant and the pollutant concentration on the gasification efficiency was investigated. Higher temperature and longer residence time enhanced the o-cresol gasification. The TOC removal rate and hydrogen gasification rate were 90.6% and 194.6%, respectively, at the temperature of 650℃ and the residence time of 0.83 min. The product gas was mainly composed of H2, CO2, CFL and CO, among which the total molar percentage of H2 and CFL was higher than 50%. The gasification efficiency decreased with the pollutant concentration increasing. Both the catalyst and oxidant could accelerate the hydrocarbon gasification at a lower reaction temperature, in which the catalyst promoted H2 production and the oxidant enhanced CO2 generation. The intermediates of liquid effluents were analyzed and phenol was found to be the main composition. The results indicate that the supercritical gasification is a promising way for the treatment of hazardous organic wastewater.
基金supported by the National Natural Science Foundation of China (No.41902154,No.51674209No.51604236)+3 种基金the Sichuan Youth Science and Technology Innovation Research Team Project (No.2021JDTDO017)the Sichuan Province Science and Technology Innovation Miaozi Engineering Cultivation Project (No.2021100)the China Scholarship Council (No.202109225004)。
文摘Shale gas reservoirs are unconventional tight gas reservoirs,in which horizontal wells and hydraulic fracturing are required to achieve commercial development.The fracture networks created by hydraulic fracturing can increase the drainage area extensively to enhance shale gas recovery.However,large volumes of fracturing fluid that is difficult to flow back to the surface and remained in the shale formation,will inevitably lead to damages of the shale formations and limit the effectiveness of stimulation.Supercritical water(SCW)treatment after hydraulic fracturing is a new method to enhance shale gas recovery by using appropriate heat treatment methods to the specific formation to convert the retained fracturing fluid into a supercritical state(at temperatures in excess of 373.946°C and pressures in excess of 22.064 MPa).An experiment was conducted to simulate the reaction between shale and SCW,and the capacity of SCW treatment to enhance the permeability of the shale was evaluated by measuring the response of the shale porosity and permeability on SCW treatment.The experimental results show that the shale porosity and permeability increase by 213.43%and 2198.37%,respectively.The pore structure alteration and permeability enhancement of the shale matrix were determined by analyzing the changes in pore structure and mineral composition after SCW treatment.The mechanisms that affect pore structure and mineral composition include oxidative catalysis decomposition of organic matters and reducing minerals,acid-catalyzed decomposition of carbonate minerals and feldspar minerals,hydrothermal catalysis induced fracture extension and cementation weakening induced fracture extension.SCW treatment converts harm into a benefit by reducing the intrusion of harmful substances into the shale formation,which will broaden the scope and scale of shale formation stimulation.
文摘Large volumes of water are generated in gas- and oil-production. This includes the water that is present originally in the reservoirs, but also water that is injected into the wells. While currently much of the produced water is either reinjected or disposed of after treatment, treated produced water is increasingly seen as an interesting resource, especially in water-scarce regions. This review looks at different PW treatment methods available, with an emphasis on the management of PW in oil- and gas production on the Arabian Peninsula.
文摘The most important waste stream created during oil and gas production is oilfield-produced water.When discharged without treatment,it poses a significant risk of pollution of marine ecosystems.While adequate treatment before disposal is acceptable,achieving authorized discharge criteria continues to be a problem for the petroleum sector.This research examined the physicochemical characteristics of produced water at various month intervals before and after treatment.Heavy metal and organic component concentrations in water samples were determined using atomic absorption spectroscopy and gas chromatography.The results indicate that produced water from a certain Niger Delta oilfield contains significant amounts of heavy metals and some organic compounds after treatment.The present laws,as well as the measurement of dispersed oil and grease content,have been in place for a long period of time without considerable change,even though most dangerous components in produced water are dissolved.It is recommendable for the prospective field developers/operators to consider the dissolved components of produced water and consider the economic consequences of adopting tertiary produced water polishing technologies.
基金financially supported by the National Natural Science Foundation of China (Nos. 22378300 and 21878215)National Key Research and Development Program of China (No.2022YFB3805202)+3 种基金Key Research and Development Program of Zhejiang Province (No. 2021C03173)Ningbo Key Research and Development Project (No. 2022Z121)Program of Introducing Talents of Discipline to Universities (No.BP0618007)Haihe Laboratory of Sustainable Chemical Transformations for financial support。
文摘Membrane technology has become one of the most promising separation technologies for its energy saving, high separation efficiency, environmental friendliness, and economic feasibility. Covalent organic frameworks(COFs) with intrinsically high porosity, controllable pore size, uniform pore size distribution and long-range ordered channel structure, have emerged as next-generation materials to fabricate advanced separation membranes. This feature article summarizes some latest studies in the development of pure COF membranes in our lab, including their fabrication and applications in chemical separations. Finally, current challenges facing high-performance COF separation membranes are discussed.
文摘Biogas is a significant renewable source as well as an alternative energy carrier provided by Anaerobic Digestion(AD)of biodegradable food wastes and other organic materials.This paper describes some major facts about biogas along with the barriers and adaptation of CBG in society,it also narrates the types of feedstocks available for biogas generation and what are the major sources in India.In this study,different stages of anaerobic digestion are discussed such as hydrolysis,acidogenesis,acetogenesis and methanogenesis for biogas production.After its purification,the biogas can be used as a fuel for domestic as well as transportation purposes.A glimpse of biogas like purification techniques like biological desulphurization,iron chloride dosing,pressure swing adsorption,chemical scrubbing and water scrubbing is given,the major additions of national policy of biofuels in 2018 is also highlighted.It has been found that in India,majorly pressure swing adsorption and water scrubbing methods are used for biogas purification,currently,the country has 12 commercial CBG plants with a total CBG output capacity of 18,461.7 tonnes per year,which is just 0.06 percent of the total ability.The details of the plants along with their CBG production capacity are described,and sustainable alternative towards affordable transportation(SATAT)launched by MoPNG is introduced in this study,furthermore,the features and types of models suggested by Ministry of Petroleum and Natural Gas(MoPNG)to introduce compressed biogas(CBG)in city gas distribution(CGD)network are discussed.
