This work presents the design of a robust foam formulation that tolerates harsh reservoir conditions(high salinity,high divalent ion concentration,high temperature,light oil,and hydrocarbon injection gas)in a sandston...This work presents the design of a robust foam formulation that tolerates harsh reservoir conditions(high salinity,high divalent ion concentration,high temperature,light oil,and hydrocarbon injection gas)in a sandstone reservoir.For this,we selected anionic Alpha Olefin Sulfonate(AOS)surfactants and studied their synergistic effects in mixtures with zwitterionic betaines to enhance foam performance.The laboratory workflow used to define the best formulation followed a de-risking approach in three consecutive phases.First,(phase 1)the main surfactant(AOS)was selected among a series of commercial candidates in static conditions.Then,(phase 2)the betaine booster to be combined with the previously selected AOS was chosen and their ratio optimized in static conditions.Subsequently,(phase 3)the surfactant/booster ratio was optimized under dynamic conditions in a porous medium in the absence and the presence of oil.As a result of this study,a mixture of an AOS C14-C16 and cocamidopropyl hydroxysultaine(CAPHS)was selected as the one having the best performance.The designed formulation was proven to be robust in a wide range of conditions.It generated a strong and stable foam at reservoir conditions,overcoming variations in salinity and foam quality,and tolerated the presence of oil.展开更多
The present work involves an extensive analytical and toxicological description of a recently identified mixed halogenated carbazole found in sediment samples,1,8-dibromo-3,6-dichloro-9H-carbazole(BCCZ).Concentrations...The present work involves an extensive analytical and toxicological description of a recently identified mixed halogenated carbazole found in sediment samples,1,8-dibromo-3,6-dichloro-9H-carbazole(BCCZ).Concentrations and the relative effect potency(REP)were calculated for the target BCCZ in a set of stream sediments collected in 2008 in Ontario,Canada.The levels calculated for BCCZ as compared to those previously assessed for legacy persistent organic pollutants(POPs)in the same samples revealed a significant contribution of BCCZ to the total organic chemical contamination(<1%e95%;average 37%).The corresponding dioxin toxic equivalencies(TEQs)of BCCZ in the sediment extracts were estimated from experimental REP data.The experimental data presented supports the classification of this emerging halogenated chemical as a contaminant of emerging environmental concern.Although potential emission sources could not be identified,this study highlights the importance of on-going research for complete characterization of halogenated carbazoles and related compounds.展开更多
基金funded by the Centro para el Desarrollo Tecnologico Industrial(CDTI)of the Spanish Ministry of Science and Innovation(IDI-20170503)the Fundacion Cepsa with the Escuela Tecnica Superior de Ingenieros de Minas y Energia of the Universidad Politecnica de Madrid(UPM)。
文摘This work presents the design of a robust foam formulation that tolerates harsh reservoir conditions(high salinity,high divalent ion concentration,high temperature,light oil,and hydrocarbon injection gas)in a sandstone reservoir.For this,we selected anionic Alpha Olefin Sulfonate(AOS)surfactants and studied their synergistic effects in mixtures with zwitterionic betaines to enhance foam performance.The laboratory workflow used to define the best formulation followed a de-risking approach in three consecutive phases.First,(phase 1)the main surfactant(AOS)was selected among a series of commercial candidates in static conditions.Then,(phase 2)the betaine booster to be combined with the previously selected AOS was chosen and their ratio optimized in static conditions.Subsequently,(phase 3)the surfactant/booster ratio was optimized under dynamic conditions in a porous medium in the absence and the presence of oil.As a result of this study,a mixture of an AOS C14-C16 and cocamidopropyl hydroxysultaine(CAPHS)was selected as the one having the best performance.The designed formulation was proven to be robust in a wide range of conditions.It generated a strong and stable foam at reservoir conditions,overcoming variations in salinity and foam quality,and tolerated the presence of oil.
基金Authors thank Conservation Ontario and the Ministry of Northern Development and Mines for this project originated from the Ontario Ministry of Northern Development and Mines through the Southern Ontario Stream Sediment Project,a partnership between Ontario Ministry of the Environment and Climate Change,Ontario Ministry of Northern Development and Mines and Conservation Ontario.
文摘The present work involves an extensive analytical and toxicological description of a recently identified mixed halogenated carbazole found in sediment samples,1,8-dibromo-3,6-dichloro-9H-carbazole(BCCZ).Concentrations and the relative effect potency(REP)were calculated for the target BCCZ in a set of stream sediments collected in 2008 in Ontario,Canada.The levels calculated for BCCZ as compared to those previously assessed for legacy persistent organic pollutants(POPs)in the same samples revealed a significant contribution of BCCZ to the total organic chemical contamination(<1%e95%;average 37%).The corresponding dioxin toxic equivalencies(TEQs)of BCCZ in the sediment extracts were estimated from experimental REP data.The experimental data presented supports the classification of this emerging halogenated chemical as a contaminant of emerging environmental concern.Although potential emission sources could not be identified,this study highlights the importance of on-going research for complete characterization of halogenated carbazoles and related compounds.