极低饱和度和近饱和状态下海水中方解石和文石溶解动力学研究

陶小晚; 蒲晓强; 王海强; 袁智; 周波

极低饱和度和近饱和状态下海水中方解石和文石溶解动力学研究

1.
中国石油勘探开发研究院,北京 100083
2.
广东海洋大学工程学院 ,广东湛江 524088
3.
中国石油集团钻井工程技术研究院,北京 100195

基金项目: 国家自然科学基金(40376038);近海海洋环境科学国家重点实验室(厦门大学)青年访问学者基金(MELRS0909)。

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出版历程
- 收稿日期: 2009-06-15

Research on dissolution kinetics of calcite and aragonite in seawater with very low saturation state and near saturation

1.
Research Institute of Petroleum Exploration & Development, PetroChina, Beijing 100083, China
2.
Engineering College, Guangdong Ocean University, Zhanjiang 524088, China
3.
CNPC Drilling Research Institute,Beijing 100195,China

摘要

摘要: 利用free-drift开放反应系统,在恒压力(101.325 kPa)和恒温度(25.0±0.2) ℃环境条件下,研究人工海水中二氧化碳分压(pCO₂)的变化对方解石和文石的溶解速率及反应级数的影响。研究结果表明:如果溶解实验中pCO₂未达到完全平衡,计算得出的反应级数偏小,且反应液pCO₂不平衡是造成不同反应阶段反应级数不同的主要原因。pCO₂平衡时,文石和方解石反应级数n都介于8.0 ~ 9.5之间,其中方解石在pCO₂为2 600×10^-6和320×10^-6条件下溶解反应级数分别为8.1和9.0;文石在pCO₂为2 300×10^-6和320×10^-6条件下的溶解反应级数分别为9.5和9.0。当反应液pCO₂平衡、Ω小于0.75时,文石的溶解速率大于方解石;当反应液pCO₂平衡、Ω大于0.8时,文石的溶解速率小于方解石。
- 人工海水 /
- 方解石 /
- 文石 /
- 溶解 /
- 动力学方程 /
- 反应级数
Abstract: The influence of variations of carbon doxide partial pressure(pCO₂) in seawater on the dissolution rate and kinetics of calcite and aragonite was studied using free-drift open reaction system which was kept at constant temperature(25.0±0.2)℃ and pCO₂(101.325 kPa). The results show that: If the pCO₂between mixture gas and reaction solution is out of balance, the deserved dissolution reaction order is smller than the actual one.The imbalance of pCO₂is the main reason for different reaction orders at different stage. In pCO₂ balance stage, the reaction order of aragonite and calcite is between 8.0 and 9.5. The reaction orders of calcite are 8.1 and 9.0 respectively with pCO₂ of 2 600×10^-6 and 320×10^-6, while for aragonite they are 9.5 and 9.0 respectively with pCO₂ of 2 600×10^-6 and 320×10^-6.When pCO₂reached a balance between the mixture gas and reaction solution, if Ω<0.75, the dissolution rate of aragonite is larger than that of calcite and if Ω>0.8 the dissolution rate of aragonite is smaller than that of calcite with the same temperature, Ω and pCO₂.
- artifical seawater /
- calcite /
- aragonite /
- dissolution /
- reaction equation /
- reaction order

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参考文献(25)

KRTZINGER A, MINTROP L, WALLACE D W R. The international at-sea intercomparison of f_CO₂ systems during the R/V Meteor Cruise 36/1 in the North Atlantic Ocean[J]. Marine Chemistry, 2000, 72(2-4):171-192.

SABINE C L, FEELY R A, GRUBER N. The oceanic sink for anthropogenic CO₂[J]. Science, 2004,305:367-371.

CICERONE R, ORR J, BREWER P, et al. The ocean in a hight-CO₂ world[J]. Oceanography,2004, 17(3):72-78.

FEELY R A, SABINE C L, LEE K, et al. Impact of anthropogenic CO₂ on the CaCO₃ system in the oceans[J]. Science,2004. 305:362-366.

MORSE J M, ARVIDSON R S. The dissolution kinetics of major sedimentary carbonate minerals[J]. Earth-Science Reviews, 2002, 58:51-84.

MORSE J W. Dissolution kinetics of calcium carbonate in seawater:Ⅵ.The near-equilibrium dissolution kinetics of calcium carbonate-rich deep sea sediments[J]. American Journal of Science,1978,278:344-353.

KEIR R S. The dissolution kinetics of biogenic calcium carbonates in seawater[J]. Geochimica et Cosmochimica Acta,1980,44: 241-252.

HALES B, EMERSON S. Evidence in support of first-order dissolution kinetics of calcite in seawater[J]. Earth and Planetary Science Letters, 1997,148(1-2): 317-327.

HALES B.Respiration, dissolution, and the lysocline[J].Paleoceanography,2003,18(4):1099.

GEHLEN M, BASSINOT F C, CHOU L,et al. Reassessing the dissolution of marine carbonates: Ⅱ. Reaction kinetics[J].Deep-Sea Research:I,2005,52: 1461-1476.

NANCOLLAS G H, KAZMLERCZAK T F, SCHUTTRINGER E. A controlled composition study of calcium carbonate crystal growth: the influence of scale inhibitors[J]. Corrosion, 1981, 37:76-80.

ZHONG S J, MUCCI A. Calcite and aragonite precipitation from seawater solutions of various salinities: precipitation rates and overgrowth compositions[J]. Chemical Geology, 1989,78:283-299.

MORSE J W. Dissolution kinetics of calcium carbonate in seawater: Ⅲ. A new method for the study of calcium carbonate reaction kinetics[J].American Journal of Science,1974,274:97-107.

MUCCI A, MORSE J W. The incorporation of Mg²⁺ and Sr²⁺ into calcite overgrowths: influences of growth rate and solution composition[J]. Geochimica et Cosmochimica Acta, 1983,47:217-233.

KAZMLERCZAK T F, TOMSON M B, NANCOLLAS G H. Crystal growth of calcium carbonate: a controlled composition kinetic study[J]. The Journal of Physical Chemistry, 1982,86:103-107.

KESTER D P, DUEDALL I W, CONNORS D N, et al. Preparation of artificial seawater[J]. Limnology and Oceanography, 1967, 12(1): 176-179.

MUCCI A. Growth kinetics and composition of magnesian calcite overgrowths precipitated from seawater-Quantitative influence of ortho-phosphate ions[J]. Geochimica et Cosmochimica Acta,1986,50:2255-2265.

WRAY J L, DANIELS F. Precipitation of calcite and aragonite[J].Journal of the American Chemical Society, 1957,79: 2031-2034.

GREGG S J, SING K S W. Adsorption, Surface Area, and Porosity[M].London: Academic Press, 1982:303.

DOE. Handbook of methods for the analysis of the various parameters of the carbon dioxide system in seawater (Version 2) //DICKSON A G, GOYET C.ORNL/CDIAC-74. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, US Department of Energy, Oak Ridge, Tennessee.1994.

TAO Xiao-wan, PU Xiao-qiang, NI Yun-yan, et al. Determination of total alkalinity and calcium concentration of seawater rapidly and automaticly with small-amount samples . 3rd International Conference on Bioinformatics and Biomedical Engineering, iCBBE 2009.

DICKSON A G. An exact definition of total alkalinity and a procedure for the estimation of alkalinity and total inorganic carbon from titration data[J]. Deep-Sea Research, 1981,28(A): 609-623.

MUCCI A. The solubility of calcite and aragonite in seawater at various salinities, temperatures and one atmosphere total pressure[J]. American Journal of Science, 1983, 283: 780-799.

KAUFMANN G, DREYBRODT W. Calcite dissolution kinetics in the system CaCO₃-H₂O-CO₂ at hith undersaturation [J]. Geochimica et Cosmochimica Acta, 2007,71: 1398-1410.

MUCCI A, SUNDBY B, GEHLEN M, et al. The fate of carbon in continental shelf sediments of eastern Canada: a case study[J]. Deep-Sea Research: Ⅱ, 2000, 47:733-760.

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