中国超基性岩封存CO2的潜力研究

摘要

大气CO<,2>浓度上升引起的气候效应正受到国际社会的高度关注.超基性岩石与CO<,2>反应可生成稳定的碳酸盐矿物而永久性地固定CO<,2>,有效地降低人类活动排放到大气中CO<,2>浓度,从而缓解日趋严重的温室效应带来的全球气候恶化.根据各省<区域地质志>记载的超基性岩体的岩石学、地球化学资料,按照公式:T=1/3·a·t·r·d·(1-φ)计算,对各省市自治区的CO<,2>封存量进行了详细统计和评估.计算表明,中国超基性岩封存CO<,2>的潜力巨大,总封存量可达13.02×10<'12>CO<,2>,约为2008年全国CO<,2>总排放量的1887倍.其中超过11.55×10<'12>t CO<,2>的封存量(占全国总量的89%)在西藏和新疆地区,其他地区占全国的11%,总量达到1.46x10<'12>tCO<,2>,相当于2008年全国总排放量的212倍,因此具有较高的碳封存潜力.由于各省工业产业结构分布的不均匀导致CO<,2>排放量有着很大的差异,因此利用超基性岩封存CO<,2>的潜力相差悬殊.东南沿海和华南地区等经济发达地区相对封存储量较少,应考虑其他方式来封存.%The global is facing a major challenge due to anthropogenic CO2 emission from the utilization of fossil fuels.Ultra-mafic rock storage is potential to reduce the atmospheric CO2 ,with high reactivity to form carbonates leading to a very stable sequestration, eventually to relief the increasingly dangerous global warming originating from the greenhouse effect.After the statistics on the data of petrology and geochemistry of the ultra-mafic rocks recorded in the regional geology of 27 provinces in China,we used the equation: T= 1/3 · a · t · r · d · (1-φ)( T is the potential CO2 storage capacity sequestrating in the ultra-mafic rocks; a is the area of the ultra-mafic rock outcrops; t is the estimated depth of the ultra-mafic rocks; r is how much CO2 can be consumed by 1 t peridotite or 1 t serpentine,which is 0. 63 t and 0. 46 t respectively; d is the densities of the ultra-mafic rocks, peridotite is 3.4g/mi3 and serpentine is 2.5g/ml3; φ is the porosity of the ultra-malic rocks, here is 0.95 )to present a preliminary investigation of potential CO2 storage capacity sequestrating in the ultra-mafic rocks of China, totally 13.02 × 1012t was estimated and is about 1887 times as against the total CO2 countrywide emission in 2008. More than 89％ ultramafic CO2 Capture and Storage(CCS) capacities are belong to Tibet and Xinjiang and these two zones will be the perspective storage candidates potentially, enormously, more than 11.55 × 1012 t CO2. The other areas are the preferential zones for CCS in near future,with totally 11％ state's storage capacities,can sequestrate more than 212 times of 2008 emission CO2 in China.Whereas,due to inhomogeneous industrial development, the CO2 emission of different provinces are diverse with each other,inducing the diverse CCS potential. The southeast coastal area such as South and East south area of China,where are the well-developed, have the major CO2 emission resources with little CCS capacities, the other geological options such as the brine aquifer, un-mineable coal seams and depleted oil and gas reservoirs in sedimentary basins located on the continental shelf may be considered.