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A cleaner production strategy for acid mine drainage prevention of waste rock:A porphyry copper case
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作者 Yesica L.Botero Isabelle Demers +2 位作者 Luis A.Cisternas ArnoldoÁvila Mostafa Benzaazoua 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第8期1163-1177,共15页
An in-process technology approach is proposed to identify the source of acid mine drainage(AMD)generation and prevent its formation in a porphyry copper waste rock(WR).Adopting actions before stockpiling the WR enable... An in-process technology approach is proposed to identify the source of acid mine drainage(AMD)generation and prevent its formation in a porphyry copper waste rock(WR).Adopting actions before stockpiling the WR enables the establishment of potential contaminants and predicts the more convenient method for AMD prevention.A WR sample was separated into size fractions,and the WR’s net acidgenerating potential was quantified using chemical and mineralogical characterization.The diameter of physical locking of sulfides(DPLS)was determined,and the fractions below the DPLS were desulfurized using flotation.Finally,the WR fractions and tailing from the flotation test were submitted to acid-base accounting and weathering tests to evaluate their acid-generating potential.Results show that the WR’s main sulfide mineral is pyrite,and the DPLS was defined as 850μm.A sulfide recovery of 91%was achieved using a combination of HydroFloat^(®)and Denver cells for a size fraction lower than DPLS.No grinding was conducted.The results show that size fractions greater than DPLS and the desulfurized WR are unlikely to produce AMD.The outcomes show that in-processing technology can be a more proactive approach and an effective tool for avoiding AMD in a porphyry copper WR. 展开更多
关键词 Waste rock Porphyry copper ore DESULFURIZATION acid mine drainage HydroFloat^(®) In-process technology Cleaner production
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Phosphorus release from phosphate rock and iron phosphate by low-molecular-weight organic acids 被引量:12
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作者 XURen-kou ZHUYong-guan DavidChittleborough 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第1期5-8,共4页
Low-molecular-weight(LMW) organic acids widely exist in soils, particularly in the rhizosphere. A series of batch experiments were carried out to investigate the phosphorus release from rock phosphate and iron phospha... Low-molecular-weight(LMW) organic acids widely exist in soils, particularly in the rhizosphere. A series of batch experiments were carried out to investigate the phosphorus release from rock phosphate and iron phosphate by low-molecular-weight organic acids. Results showed that citric acid had the highest capacity to solubilize P from both rock and iron phosphate. P solubilization from rock phosphate and iron phosphate resulted in net proton consumption. P release from rock phosphate was positively correlated with the p K _a values. P release from iron phosphate was positively correlated with Fe-organic acid stability constants except for aromatic acids, but was not correlated with p K _a. Increase in the concentrations of organic acids enhanced P solubilization from both rock and iron phosphate almost linearly. Addition of phenolic compounds further increased the P release from iron phosphate. Initial solution pH had much more substantial effect on P release from rock phosphate than from iron phosphate. 展开更多
关键词 organic acid phosphate release RHIZOSPHERE rock phosphate iron phosphate
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The effects of temperature and acid number of crude oil on the wettability of acid volcanic reservoir rock from the Hailar Oilfi eld 被引量:5
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作者 Xie Quan He Shunli Pu Wanfeng 《Petroleum Science》 SCIE CAS CSCD 2010年第1期93-99,共7页
Wettability of acid volcanic reservoir rock from the Hailar Oilfield, China, was studied with crude oils of different acid numbers generated from an original crude oil with an acid number of 3.05 mg KOH/g. The modifed... Wettability of acid volcanic reservoir rock from the Hailar Oilfield, China, was studied with crude oils of different acid numbers generated from an original crude oil with an acid number of 3.05 mg KOH/g. The modifed oils and their resultant acid numbers were: A (2.09 mg KOH/g), B (0.75 mg KOH/g), C (0.47 mg KOH/g), D (0.30 mg KOH/g), and E (0.18 mg KOH/g). Contact angles and improved Amott water indexes were measured to study the effects of temperature and acid number on the wettability of the acid volcanic reservoir rock. Experimental results indicated that the wettability was not sensitive to variation in temperature when using the same oil, but the acid number of the crude oil was a key factor in changing the wettability of the rock. The Amott water index, Iw was an exponential function of the acid number, and the Amott water index increased as the acid number decreased (i.e. Amott water index exponentially decreased with the acid number increase). The Iw value of the core saturated with oil A, with an acid number of 2.09 mg KOH/g, ranged from 0.06 to 0.11, which indicated low water wetness. If the acid number of the oil decreased to 0.18 mg KOH/g, the Iw value increased to 0.95, which indicated strong water wetness. The contact angle decreased from 80~ to 35~ when the aid number decreased from 0.75 to 0.18 mg KOH/g, indicating a change towards more water wet conditions. The oil recovery by spontaneous imbibition of water also increased as the acid number of the oil decreased. As an example, at 80 ~C, the recovery of Oil A with an acid number of 2.09 mg KOH/g was only 7.6%, while Oil E with an acid number of 0.18 mg KOH/g produced 56.4%, i.e. an increase of 48.8%. 展开更多
关键词 acid volcanic reservoir rock Amott wettability index wetting angle TEMPERATURE acid number WETTABILITY
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Application of Ground Phosphate Rock to Dimmish the Effects of Simulated Acid Rain on Soil Properties 被引量:1
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作者 DONG YUAN-VAN and LI XUE-YUAN Huazhong Agricultural University. Wuhan 430070 ( China) 《Pedosphere》 SCIE CAS CSCD 1992年第2期147-152,共6页
The effects of simulated acid rain retained in soil on the properties of acid soil and its diminishing by application of ground phosphate rock were investigated by using the sorption method. Results show as follows: (... The effects of simulated acid rain retained in soil on the properties of acid soil and its diminishing by application of ground phosphate rock were investigated by using the sorption method. Results show as follows: (1) For yellow brown soil, the effect of simulated acid rain on the properties of soil with a pH value of 5.9 was relatively small, except a great quantity of acid rain deposited on it. (2) For red soil, the effect of simulated acid rain on the properties of soil was significant. With the increase of the amount of acid deposition, the pH value of soil was declined, but the contents of exchangeable H+, Al3+ and Mn2+ and the amount of SO42- retention were increased. (3) Many properties of acid soils could be improved by applying ground phosphate rock. For example, pH value of soils and the amounts of available P and exchangeable Ca2+ and Mg2+ were increased, and the amounts of exchangeable H+ and Al3+ and SO42- retained was reduced. The application of ground posphate rock could effctively dimmish the pollution of acid rain to soil. 展开更多
关键词 phosphate rock simulated acid rain soil properties
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Acid Sulfate Soil Induced Acidification of Estuarine Areas Used for the Production of Sydney Rock Oysters, <i>Saccostrea glomerata</i>
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作者 Michael C. Dove Jesmond Sammut 《Journal of Water Resource and Protection》 2013年第3期320-335,共16页
This study investigated estuarine acidification, associated with drainage and excavation of acid sulfate soils, in areas used for commercial cultivation of Sydneyrock oysters (Saccostrea glomerata). Regular measuremen... This study investigated estuarine acidification, associated with drainage and excavation of acid sulfate soils, in areas used for commercial cultivation of Sydneyrock oysters (Saccostrea glomerata). Regular measurements of pH and electrical conductivity were collected in oyster cultivation areas and acidified reaches of the Hastings River estuary and Port Stephens estuary located on the mid north coast of New South Wales, Australia. Water quality information from acidified floodplain drains was also collected in theHastingsRiverfollowing heavy rainfall. Both estuaries experienced acidification of tributaries following periods of heavy rainfall. Drain outflow waters were acidic 展开更多
关键词 ESTUARINE acidIFICATION acid Sulfate Soil SYDNEY rock Oyster Saccostrea glomerata New South Wales
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Hydrochemistry of Surface and Groundwater in the Vicinity of a Mine Waste Rock Dump: Assessing Impact of Acid Rock Drainage (ARD)
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作者 Francis Krampah George Lartey-Young +2 位作者 Peter O. Sanful Oscar Dawohoso Austin Asare 《Journal of Geoscience and Environment Protection》 2019年第1期52-67,共16页
Acid Rock Drainage (ARD) is a well-known problem related to the mining industry due to its hazardous environmental effects. Metal-rich drainage and acid effluent transmitted from mine waste dumps compromise environmen... Acid Rock Drainage (ARD) is a well-known problem related to the mining industry due to its hazardous environmental effects. Metal-rich drainage and acid effluent transmitted from mine waste dumps compromise environmental quality of groundwater and surface water systems destroying aquatic life and increasing human health risks. This study was aimed at assessing the acid and metal drainage potential from the Subriso East Rock Dump (SERD) located in the Wassa East district of Ghana on ground and surface water quality in the catchment using a system of monitoring boreholes, reference boreholes and river samples. Water samples were collected from deep and shallow monitoring boreholes and surface water within the immediate environs of the SERD from August 2012 to February 2013 for laboratory and statistical analysis. Parameters analyzed include sulphate, alkalinity, Arsenic (As), Manganese (Mn), Iron (Fe), Zinc (Zn), Copper (Cu), Cadmium (Cd), Mercury (Hg), Aluminum (Al), Silver (Ag) and lead (Pb) and their concentrations compared with Ghana Standards Authority (GSA) GSB (2009) and WHO (2017) standards. Results indicate that surface and groundwater were not impacted by the SERD possibly because there was no generation of acid or metal-loaded effluent from the SERD into the environment. Physicochemical variables between monitoring boreholes did not differ significantly from conditions in the reference boreholes. Similarly, comparison of upstream and downstream river conditions did not yield any statistical significance (p > 0.05). Mn and Fe concentrations were above the WHO (2017)/GSB (2009) standards. Heavy metal concentrations in surface and groundwater were below detection limits except manganese and iron whose concentrations exceeded the recommended guidelines. No significant environmental impacts exist that could be attributed to the waste rock dump and may be as a result of engineering designs and mechanisms which prevent acid generated water from reaching the external environment. Furthermore, the geology of the study area potentially could be slightly inert having the potential to generate ARD under appropriate conditions. Again, the young age of the waste rock dump is a factor that may contribute to ARD generation under appropriate condition. Routine monitoring of groundwater and surface water sources is required to determine future acid generation of the SERD and its environmental impacts. The results of this study will assist decision makers and environmental managers to plan effectively to mitigate future impacts as mining waste rock dumps are known to increase in acid generation potential with age. 展开更多
关键词 Waste rock DUMP acid rock Drainage SURFACE WATER Ground WATER Wassa East District WATER Quality
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Electrokinetics Technology to Improve Acidizing of Carbonate Reservoir Rocks
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作者 Sanghee Shin George V. Chilingar +5 位作者 Mohammed Haroun Kenneth Wittle Najmedin Meshkati Sibel Pamukcu Jaehyeung Jeoung Hobon Koo 《Journal of Environmental Protection》 2013年第4期1-3,共3页
A novel technology (electrokinetics) is proposed to improve acidizing operations, i.e., increase the penetration distance. The acid dissolves the carbonates (limestones/dolomites), enlarging the pores and increasing t... A novel technology (electrokinetics) is proposed to improve acidizing operations, i.e., increase the penetration distance. The acid dissolves the carbonates (limestones/dolomites), enlarging the pores and increasing the width of pre-existing fractures. This gives rise to an increase in permeability. The principal acid commonly used is hydrochloric (HCl), which is pumped through tubing. Aqueous solutions of hydrochloric acid (usually 15%) are pumped into the carbonate formations to enlarge the pores and pre-existing fractures. Without application of D.C. current, the penetration distance is usually very short, especially in tight rocks. However, the penetration distance of acid is very short. By applying D.C. current, one can drive the acid for long distances into the formation being acidized. 展开更多
关键词 acidIZING Electorkinetics CARBONATE rockS PENETRATION DISTANCE STIMULATION
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Jebel Kurun Phosphate Rock Characteristics and Technical Viability to Produce Phosphoric Acid
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作者 Mohamed E. Elmahdi Kamil M. Wagialla 《Journal of Minerals and Materials Characterization and Engineering》 2018年第5期555-567,共13页
The technical viability for utilizing Jebel Kurun phosphate reserve in Sudan for the production of a fertilizer grade phosphoric acid is assessed. Statistical analysis has been carried for 56 samples. Phosphate rock h... The technical viability for utilizing Jebel Kurun phosphate reserve in Sudan for the production of a fertilizer grade phosphoric acid is assessed. Statistical analysis has been carried for 56 samples. Phosphate rock has been classified into three main types and then the number of samples representing each type has been identified. Average values for phosphorus pentoxide is 19% and for uranium is 81.47 ppm. The most abundant elements are silicon, aluminum, phosphorus, calcium and iron. Aluminophosphate ore (CaO% ≤ 12%, Al2O3% ≥ 20%, P2O5% ≥ 18%) is represented by 55.36% of sampled phosphate rock. This type can be used to produce phosphoric acid when P2O5 > 30%. Apatite rock including aluminophosphate CaO% ≥ 25%, Al2O3% ≤ 10%, P2O5% ≥ 20%, 12% ≤ SiO2 ≤ 35% is represented by 1.79% of sampled phosphate rock, this type can be used to produce phosphoric acid when it can meet the requirements of (CaO% ≥ 30%, Al2O3% ≤ 7%, P2O5% ≥ 25%, SiO2% ≤ 30%). Silica ore including phosphorus (SiO2% ≥ 40%, P2O5% ≤ 10%) is represented by 16.07% of sampled phosphate rock and Iron ore including phosphorus (Fe2O3% ≥ 20%, P2O5% ≤ 10%) is represented by 5.36% of samples. Both types cannot be used to produce phosphoric acid. The statistical distribution of P2O5 in the size fractions for a core drilled samples is required. 展开更多
关键词 PHOSPHATE rock Jebel Kurun Phosphoric acid Production Technical VIABILITY Statistical Analysis
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Agronomic Potential of Partially Acidnlated Rock Phos-phates in Acid Soils of Subtropical China
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作者 XIONGLI-MING B.TRUONG 《Pedosphere》 SCIE CAS CSCD 1995年第2期97-105,共9页
A glasshouse experiment was conducted to evaluate the agronomic potential of four partially acidulatedrock phosphates (PARP) in three representative soils sampled from subtropical China. The PARPs weremanufactured by ... A glasshouse experiment was conducted to evaluate the agronomic potential of four partially acidulatedrock phosphates (PARP) in three representative soils sampled from subtropical China. The PARPs weremanufactured by attacking a moderately reactive phosphate rock either with sulfuric acid alone or withcombination of sulfuric and phosphoric acids at 30 or 60 percent of acidulation. Shoot dry weight and Paccumulation of six successive cuttings of ryegrass were used to compare the agronomic potential of thesefertilizers with that of the raw rock phosphate (RP) and monocalcium phosphate (MCP). Results indicatedthat the effectiveness of various phosphates was determined both by the solubility of the phosphates andby the acidity and P-fixing capacity of the soils. The higher the watersoluble P contained, the better theeffectiveness of the fertilizer was. Although plant P accumulation of PARP treatments was constantly lowerthan that of MCP treatment, some PARPs could still get a dry matter production similar to that of MCPtreatment. PARP SP60, which was acidulated with a mixture of sulfuric acid and phosphoric acid at 60percent of acidulation and contained the highest soluble P, was as effective as MCP in terms of dry matterproduction on all the soils. 560 and C1, which were both acidulated with sulfuric acid with the formerat 60 percent of acidulation and the latter at 30 percent but with a further addition of monoarninoniumphosphate, were more than 80 percent as effective as MCP. Raw RP also showed a reasonable effectivenesswhich increased with soil acidity. It was suggested from the study that some of these PARPs could beexpected to have a comparable field performance as soluble P fertilizers in the acid soil regions. 展开更多
关键词 acid soil agronomic potential partially acidulated rock phosphate
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Dissolution of Calcareous Phosphate Rock from Gafsa (Tunisia) Using Dilute Phosphoric Acid Solution
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作者 Houda Lefires Hayet Medini +1 位作者 Adel Megriche Arbi Mgaidi 《International Journal of Nonferrous Metallurgy》 2014年第1期1-7,共7页
In the present study, porous structure of raw and calcined phosphate ore particles was examined. The specific surface area and the pore volume were determined by nitrogen adsorption. Raw particles and calcined ores we... In the present study, porous structure of raw and calcined phosphate ore particles was examined. The specific surface area and the pore volume were determined by nitrogen adsorption. Raw particles and calcined ores were leached using dilute phosphoric acid solution (4% P2O5). In all cases, the ESEM (Environmental Scanning Electron Microscopy) observations show that the grain of phosphate holds its shape ovoidale. The sample heated at 780?C presented the lowest specific surface area 0.6 m2/g at each reaction time, and the unreacted phases were analysed using XRD, FT-IR, Nitrogen adsorption and ESEM observations. The selective leaching curves were evaluated in order to test the validity of kinetics models. A mathematical model in the following form was applied. The dissolution of the two samples (raw and calcined phosphate) has been observed to take place in two steps: the first being fast and the second being slow. 展开更多
关键词 PHOSPHATE rock DISSOLUTION Phosphoric acid POROSITY Evolution DISSOLUTION KINETICS
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Formation of fractures in carbonate rocks by pad acid fracturing with different states of carbon dioxide
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作者 GUO Jianchun ZHAN Li +4 位作者 GOU Bo ZHANG Ran LIU Chao LI Xiao REN Jichuan 《Petroleum Exploration and Development》 CSCD 2021年第3期744-751,共8页
Carbonate outcrops were taken from Ma 51 sub-member in the Lower Paleozoic in the Yan’an gas field to conduct true tri-axial hydraulic fracturing experiments with water, liquid CO_(2) and supercritical CO_(2). CT sca... Carbonate outcrops were taken from Ma 51 sub-member in the Lower Paleozoic in the Yan’an gas field to conduct true tri-axial hydraulic fracturing experiments with water, liquid CO_(2) and supercritical CO_(2). CT scan was applied to analyze initiation and propagation laws of hydraulic fractures in carbonate rocks. The experiments show that supercritical CO_(2) has low viscosity, strong diffusivity and large filtration during fracturing, which is more liable to increase pore pressure of rocks around wellbore and decrease breakdown pressure of carbonate rocks. However, it would cost much more volume of supercritical CO_(2) than water to fracture rocks since the former increases the wellbore pressure more slowly during fracturing. For carbonate rocks with few natural fractures, tensional fractures are generated by fracturing with water and liquid CO_(2), and these fractures propagate along the maximum horizontal principal stress direction;while fracturing with supercritical CO_(2) can form shear fractures, whose morphology is rarely influenced by horizontal stress difference. Besides, the angle between propagation direction of these shear fractures near the wellbore and the maximum horizontal principal stress is 45°, and the fractures would gradually turn to propagate along the maximum horizontal principal stress when they extend to a certain distance from the wellbore, leading to an increase of fracture tortuosity compared with the former. For carbonate rocks with well-developed natural fractures, fracturing with fresh water is conducive to connect natural fractures with low approaching angle and form stepped fractures with simple morphology. The key to forming complex fractures after fracturing carbonate rocks is to connect the natural fractures with high approaching angle. It is easier for liquid CO_(2) with low viscosity to realize such connection. Multi-directional fractures with relatively complex morphology would be formed after fracturing with liquid CO_(2). 展开更多
关键词 carbonate rock pad acid fracturing liquid CO_(2) supercritical CO_(2) fracture initiation fracture propagation
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Attenuation of aqueous metal transport at two natural acid rock drainage occurrences in the Yukon Territory, Canada
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作者 Y.T. John Kwong 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期229-230,共2页
关键词 酸性排水 金属污染 地球化学 堆积物
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丹参酚酸B盐抑制大鼠肝星状细胞中内皮素-1激活的RhoA/ROCK Ⅱ信号通路 被引量:2
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作者 徐虹 平键 +2 位作者 卢超 周扬 徐列明 《肝脏》 2014年第4期261-265,共5页
目的探讨丹参酚酸B盐(Sal B)对大鼠肝星状细胞(HSC)中内皮素-1(ET-1)激活的RhoA/ROCK信号通路的影响。方法采用肝脏原位灌流酶消化、Nycodenz密度梯度离心法分离大鼠HSC。免疫蛋白印迹法检测肌球蛋白磷酸酶靶亚基1(MYPT1)磷酸化。特异... 目的探讨丹参酚酸B盐(Sal B)对大鼠肝星状细胞(HSC)中内皮素-1(ET-1)激活的RhoA/ROCK信号通路的影响。方法采用肝脏原位灌流酶消化、Nycodenz密度梯度离心法分离大鼠HSC。免疫蛋白印迹法检测肌球蛋白磷酸酶靶亚基1(MYPT1)磷酸化。特异性抗体沉淀ROCK,进行体外磷酸化反应,以磷酸化底物Thr696-MYPT1(654-880)的含量反映ROCK活性。GST下拉实验检测RhoA活性。结果在大鼠HSC中,ET-1刺激后,RhoA和ROCK Ⅱ活性显著增加,ROCK I活性无明显变化,MYPT1 Thr696和Thr850磷酸化水平均显著增加。ET-1刺激1 min和10 min时,RhoA活性分别是基础状态下的1.95倍(P<0.05)和5.84倍(P<0.01)。ET-1刺激2.5 min和15 min时,ROCK Ⅱ活性分别是基础状态下的3.49倍和4.83倍,均P<0.01,差异有统计学意义。ET-1刺激2.5 min时,MYPT1 Thr696磷酸化水平是基础状态下的3.86倍;刺激15 min时,Thr696磷酸化达到高峰,是基础状态下的5.17倍。Thr850磷酸化亦在ET-1刺激15 min达到高峰,是基础状态下的3.33倍,均P<0.01,差异有统计学意义。在ET-1刺激前给予10-5 mol/L Sal B预处理,则使ET-1诱导的RhoA和ROCK Ⅱ活性分别下降66.84%和76.79%,ET-1诱导的MYPT1 Thr696磷酸化下降80.09%,对Thr850磷酸化水平无影响。结论 Sal B能显著抑制大鼠HSC中ET-1诱导的RhoA和ROCK Ⅱ活化,抑制MYPT1Thr696磷酸化。 展开更多
关键词 肝星状细胞 内皮素-1 丹参酚酸B RHOA rock信号通路
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Solubilization of Rock Phosphate in Liquid Culture by Fungal Isolates from Rhizosphere Soil 被引量:6
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作者 WANG Guang-Hua ZHOU De-Rui +2 位作者 YANG Qian JIN Jian LIU Xiao-Bing 《Pedosphere》 SCIE CAS CSCD 2005年第4期532-538,共7页
Rock phosphate (RP) is a low efficiency P fertilizer that is directly applied to the soil and can be solubilized by phosphate-solubilizing microorganisms (PSMs) in fermentation or soil conditions. This study inves... Rock phosphate (RP) is a low efficiency P fertilizer that is directly applied to the soil and can be solubilized by phosphate-solubilizing microorganisms (PSMs) in fermentation or soil conditions. This study investigated dynamic solubilization of 2 concentrations of rock phosphate in a liquid culture with different dosages of glucose by two fungal isolates,Aspergillus niger P39 and Penicillium oxalicum P66, from soybean and wheat rhizosphere soil. Although during the 20 day culture period A. niger P39 had a stronger ability to acidify the culture media than P. ozalicum P66, soluble P concentrations at glucose dosages of 30 and 50 g L^-1 with RP of 15 g L^-1 in the culture solution were much higher by P. oxalicum P66. The greater effectiveness of P. oxalicum P66 compared to A. niger P39 in the solubilization of RP was strongly associated with the production of organic acids. This study suggested that for RP solubilization the type rather than the concentration of PSM-produced organic acids was more important. 展开更多
关键词 Aspergillus niger organic acids Penicillium oxalicum phosphate solubilization rock phosphate
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Impact of Montmorillonite and Calcite on Release and Adsorption of Cyanobacterial Fatty Acids at Ambient Temperature 被引量:1
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作者 刘邓 杨小芬 +2 位作者 王红梅 李继红 苏念 《Journal of China University of Geosciences》 SCIE CSCD 2008年第5期526-533,共8页
Minerals might act as important sorbents of sedimentary organic matter and reduce biodegradation, which favors the formation of hydrocarbon source rocks in the earth's history. Since most organic matter is degraded d... Minerals might act as important sorbents of sedimentary organic matter and reduce biodegradation, which favors the formation of hydrocarbon source rocks in the earth's history. Since most organic matter is degraded during the sinking process, at ambient temperature, it is important to investigate the adsorption capacity of different minerals during this process, to assess the organic loss from primary productivity to sedimentary organic matter. In this study, montmorillonite and calcite have been selected to study the impact of different minerals on the release, adsorption, and deposition of cyanobacterial (Synechococcus elonpata) fatty acids (FAs) at ambient temperature. Gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) have been utilized to detect the variation in fatty acids. Primary results suggest that minerals have a different impact on dissolved organic matter. Montmorillonite can specifically enhance the release of fatty acids from cyanobacterial cells by lowering the pH values of the solution. The adsorption of the dissolved organic matter by montmoriilonite will also be enhanced under a lower pH value. Conjunction of fatty acids with montmoriilonite to form a complex will favor the sinking and preservation of these organics. Selective adsorption is observed among fatty acids with different carbon numbers. In contrast, calcite does not show any impact on the release and adsorption of organic matter even though it is reportedly capable of acting as a catalyst during the transformation of organic matter at high temperature. The primary data bridge a link between primary productivity and sedimentary organic matter, suggesting the relative importance of claystones in the formation of hydrocarbon source rocks in the earth's history. 展开更多
关键词 adsorption capacity MONTMORILLONITE CALCITE fatty acid hydrocarbon bed source rock.
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Static dissolution-induced 3D pore network modification and its impact on critical pore attributes of carbonate rocks 被引量:2
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作者 ANDRIAMIHAJA Spariharijaona PADMANABHAN Eswaran +1 位作者 BEN-AWUAH Joel SOKKALINGAM Rajalingam 《Petroleum Exploration and Development》 2019年第2期374-383,共10页
To determine the effect of dissolution on pore network development in carbonate rocks, dissolution experiments, X-Ray microtomography, and thin section analysis were conducted on argillaceous limestone and grain limes... To determine the effect of dissolution on pore network development in carbonate rocks, dissolution experiments, X-Ray microtomography, and thin section analysis were conducted on argillaceous limestone and grain limestone samples at different temperatures and constant pH, HCl concentration. The relationship between Ca^(2+) concentration and time was revealed through the experiments; pore size distribution before and after dissolution indicate that there is no correlation between the temperature and pore size variation, but pore size variation in grain limestone is more significant, indicating that the variation is mainly controlled by the heterogeneity of the rock itself(initial porosity and permeability) and the abundance of unstable minerals(related to crystal shape, size and mineral type). At different temperatures, the two kinds of carbonate rocks had very small variation in pore throat radius from 0.003 mm to 0.040 mm, which is 1.3 to 3.5 times more, 1.7 on average of the original pore throat radius. Their pore throat length varied from 0.05 mm to 0.35 mm. The minor changes in the pore throat radius, length and connectivity brought big changes to permeability of up to 1 000×10^(-3) μm^2. 展开更多
关键词 3D PORE networks CARBONATE rockS PORE structure MUDSTONE grainstone acidIZING dissolution X-Ray micro tomography
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Characteristics and tectonic setting of volcanic rocks in Early Cretaceous Baiyingaolao Formation of Keyouzhongqi area,Inner Mongolia 被引量:8
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作者 KONG Yuanming MA Rui +3 位作者 HE Zhonghua YANG Deming WU Qing WANG Yang 《Global Geology》 2014年第2期78-85,共8页
The authors studied zircon LA-ICP-MS U-Pb dating,the zircon Hf isotope and geochemistry of acidic volcanic rocks in Baiyingaolao Formation of Keyouzhongqi area,Inner Mongolia,and discussed the chronology,source region... The authors studied zircon LA-ICP-MS U-Pb dating,the zircon Hf isotope and geochemistry of acidic volcanic rocks in Baiyingaolao Formation of Keyouzhongqi area,Inner Mongolia,and discussed the chronology,source region and tectonic setting of the volcanic rocks in the studied area. The clear oscillatory zoning of zircons indicates a typical magmatic origin,and the results of dating show that the volcanic rocks of Baiyingaolao Formation were formed in Early Cretaceous( 121. 5 ± 1. 0 Ma). The features of major and trace elements show that the rocks are alkali-rich,poor in calcium and magnesium with enrichment in LILEs like Th,U,K and Gd and depletion in HFSEs,e. g. Nb,Ta,Sr and Ti. The fact implies that they were the products of partial melting of the crust. εHf( t) =( +6.30--+9.06) and TDM2= 600--835 Ma,suggest the magma originated from partial melting of the young crust. Combined with the evolution of regional tectonic structure,the authors conclude that the acidic volcanic rocks of Baiyingaolao Formation may be formed under the extensional environment related to the subduction of Paleo-Pacific Plate. 展开更多
关键词 Daxing'anling Baiyingaolao Formation acidic volcanic rocks Early Cretaceous zircon U-Pb dating
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Geochemical and Sr-Nd-Pb isotopic compositions of volcanic rocks from the Iheya Ridge,the middle Okinawa Trough:implications for petrogenesis and a mantle source 被引量:7
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作者 LI Xiaohui ZENG Zhigang +4 位作者 CHEN Shuai MA Yao YANG Huixin ZHANG Yuxiang CHEN Zuxing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第1期73-88,共16页
As an active back-arc basin, the Okinawa Trough is located in the southeastern region of the East China Sea shelf and is strongly influenced by the subduction of the Philippine Sea Plate. Major element, trace element ... As an active back-arc basin, the Okinawa Trough is located in the southeastern region of the East China Sea shelf and is strongly influenced by the subduction of the Philippine Sea Plate. Major element, trace element and Sr-NdPb isotopic composition data are presented for volcanic rocks from the Iheya Ridge(IR), the middle Okinawa Trough. The IR rocks record large variations in major elements and range from basalts to rhyolites. Similar trace element distribution characteristics together with small variations in ^87Sr/^86Sr(0.703 862–0.704 884), ^144Nd/^143Nd(0.512 763–0.512 880) and Pb isotopic ratios, demonstrate that the IR rocks are derived from a similar magma source. The fractional crystallization of olivine, clinopyroxene, plagioclase, and amphibole, as well as accessory minerals, can reasonably explain the compositional variations of these IR rocks. The simulations suggest that approximately 60% and 75% fractionation of an evolved basaltic magma can produce trace element compositions similar to those of the intermediate rocks and acid rocks, respectively. The analysis of their Sr-Nd-Pb isotopic content ratios suggest that the source of the rocks from the IR is close to the depleted mantle(DM) but extends to the enriched mantle(EMII), indicating that the mantle source of these rocks is a mixture between the DM and EMII end members. The simulations show that the source of the IR volcanic rocks can be best interpreted as the result of the mixing of approximately 0.8%–2.0% subduction sediment components and 98.0%–99.2% mantlederived melts. 展开更多
关键词 basic to intermediate-acid rocks fractional crystallization subduction sediment components Iheya Ridge Okinawa Trough
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Development of Acidizing Techniques for Low-permeability Carbonate Reservoirs
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作者 Liu Tongbin(Senior Engineer, Sichuan Petroleum Administration) 《China Oil & Gas》 CAS 1996年第4期208-209,共2页
DevelopmentofAcidizingTechniquesforLow-permeabilityCarbonateReservoirsLiuTongbin(SeniorEngineer,SichuanPetro... DevelopmentofAcidizingTechniquesforLow-permeabilityCarbonateReservoirsLiuTongbin(SeniorEngineer,SichuanPetroleumAdministratio... 展开更多
关键词 CARBONATE rock Low PERMEABILITY RESERVOIR acidIZING Technique DEVELOPMENT
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Physico-Chemical Study of Silica Rocks from the East Coast Malaysia Region for Crystal Glass Application
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作者 Syarifah Aminah Ismail Muhammad Kamal Kamarudin +1 位作者 Mohamad Haniza Mahmud Mohd Idham 《Journal of Geological Resource and Engineering》 2020年第4期106-113,共8页
The main objective of the current work is to recover SiO2 various acid concentrations,scrubbing time,and attrition impeller speed for crystal glass application.Silica rocks were treated using a physico-chemical method... The main objective of the current work is to recover SiO2 various acid concentrations,scrubbing time,and attrition impeller speed for crystal glass application.Silica rocks were treated using a physico-chemical method involving physical separation method using citric and sulphuric acids as the reagents.Low acid concentration range of 1%-2%and variable scrubbing time of 10,20,and 30 min were investigated.The microstructure,phase,and particle size of the silica rocks were determined after scrubbing process.Citric acid was found effective in improving the purity of SiO2 to 99.8%at 0.75%concentration,via a 20 min scrubbing process operated at 1,250 rpm(rotations per minute).The phase structure and morphology of the recovered SiO2 were confirmed as trigonal crystal structure with small and irregular shape.To date,studies on the processing of silica rock using organic acid are yet very limited. 展开更多
关键词 Silica rocks acid concentration citric acid attrition scrubber
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