The issues of reducing CO_2 emissions, sustainably utilizing natural mineral resources, and dealing with industrial waste offer challenges for sustainable development in energy and the environment. We propose an effic...The issues of reducing CO_2 emissions, sustainably utilizing natural mineral resources, and dealing with industrial waste offer challenges for sustainable development in energy and the environment. We propose an efficient methodology via the co-reaction of K-feldspar and phosphogypsum for the extraction of soluble potassium salts and recovery of SO_2 with reduced CO_2 emission and energy consumption. The results of characterization and reactivity evaluation indicated that the partial melting of K-feldspar and phosphogypsum in the hightemperature co-reaction significantly facilitated the reduction of phosphogypsum to SO_2 and the exchange of K^+(K-feldspar) with Ca^(2+)(CaSO_4 in phosphogypsum). The reaction parameters were systematically investigated with the highest sulfur recovery ratio of ~ 60% and K extraction ratio of ~ 87.7%. This novel methodology possesses an energy consumption reduction of ~ 28% and CO_2 emission reduction of ~ 55% comparing with the present typical commercial technologies for utilization of K-feldspar and the treatment of phosphogypsum.展开更多
Carbon dioxide injection into deep saline aquifers results in a variety of strongly coupled physical and chemical processes. In this study, reactive transport simulations using a 2-D radial model were performed to inv...Carbon dioxide injection into deep saline aquifers results in a variety of strongly coupled physical and chemical processes. In this study, reactive transport simulations using a 2-D radial model were performed to investigate the fate of the injected CO2, the effect of CO2-water-rock interactions on mineral alteration, and the long-term CO2 sequestration mechanisms of the Liujiagou Formation sandstone at the Shenhua CCS（carbon capture and storage） pilot site of China. Carbon dioxide was injected at a constant rate of 0.1 Mt/year for 30 years, and the fluid flow and geochemical transport simulation was run for a period of 10 000 years by the TOUGHREACT code according to the underground conditions of the Liujiagou Formation. The results show that different trapping phases of CO2 vary with time. Sensitivity analyses indicate that plagioclase composition and chlorite presence are the most significant determinants of stable carbonate minerals and CO2 mineral trapping capacity. For arkosic arenite in the Liujiagou Formation, CO2 can be immobilized by precipitation of ankerite, magnesite, siderite, dawsonite, and calcite for different mineral compositions, with Ca（2＋）, Mg（2＋）, Fe（2＋） and Na＋ provided by dissolution of calcite, albite（or oligoclase） and chlorite. This study can provide useful insights into the geochemistry of CO2 storage in other arkosic arenite（feldspar rich sandstone） formations at other pilots or target sites.展开更多
基金Supported by the National Natural Science Foundation of China(21336004)the State Key Research Plan of the Ministry of Science and Technology(2013BAC12B03)
文摘The issues of reducing CO_2 emissions, sustainably utilizing natural mineral resources, and dealing with industrial waste offer challenges for sustainable development in energy and the environment. We propose an efficient methodology via the co-reaction of K-feldspar and phosphogypsum for the extraction of soluble potassium salts and recovery of SO_2 with reduced CO_2 emission and energy consumption. The results of characterization and reactivity evaluation indicated that the partial melting of K-feldspar and phosphogypsum in the hightemperature co-reaction significantly facilitated the reduction of phosphogypsum to SO_2 and the exchange of K^+(K-feldspar) with Ca^(2+)(CaSO_4 in phosphogypsum). The reaction parameters were systematically investigated with the highest sulfur recovery ratio of ~ 60% and K extraction ratio of ~ 87.7%. This novel methodology possesses an energy consumption reduction of ~ 28% and CO_2 emission reduction of ~ 55% comparing with the present typical commercial technologies for utilization of K-feldspar and the treatment of phosphogypsum.
基金supported by the Global Climate and Energy Project(No.2384638-43106-A)the National Natural Science Foundation of China(No.41072180)+1 种基金the Special Scientific Research Fund of Public Welfare Profession of the Ministry of Land and Resources of China(No.201211063)a bilateral project of China Australia Geological Storage of CO2 Project Phase 2(CAGS2)
文摘Carbon dioxide injection into deep saline aquifers results in a variety of strongly coupled physical and chemical processes. In this study, reactive transport simulations using a 2-D radial model were performed to investigate the fate of the injected CO2, the effect of CO2-water-rock interactions on mineral alteration, and the long-term CO2 sequestration mechanisms of the Liujiagou Formation sandstone at the Shenhua CCS（carbon capture and storage） pilot site of China. Carbon dioxide was injected at a constant rate of 0.1 Mt/year for 30 years, and the fluid flow and geochemical transport simulation was run for a period of 10 000 years by the TOUGHREACT code according to the underground conditions of the Liujiagou Formation. The results show that different trapping phases of CO2 vary with time. Sensitivity analyses indicate that plagioclase composition and chlorite presence are the most significant determinants of stable carbonate minerals and CO2 mineral trapping capacity. For arkosic arenite in the Liujiagou Formation, CO2 can be immobilized by precipitation of ankerite, magnesite, siderite, dawsonite, and calcite for different mineral compositions, with Ca（2＋）, Mg（2＋）, Fe（2＋） and Na＋ provided by dissolution of calcite, albite（or oligoclase） and chlorite. This study can provide useful insights into the geochemistry of CO2 storage in other arkosic arenite（feldspar rich sandstone） formations at other pilots or target sites.
