基于层次分析法的浅层地温能适宜性评价分析—以兰州市中心城区为例

Abstract

依据实际勘查资料和测试数据，采用层次分析法所建立的数学评价模型，对兰州市中心城区面积384.7km2的区域进行了浅层地温能适宜性评价分析。浅层地温能适宜性评价体系地下水源热泵共建立了3个属性准则和10个要素指标，土源热泵共建立了3个属性准则和8个要素指标，分别构建了各层次的判断矩阵，并全部高精度通过一致性验证。评价结果，地下水源热泵适宜、较适宜区占调查区总面积的38.99%，主要分布于断陷盆地及黄河黄河I~III级阶地区及和平、定远盆地大部等含水层富水性较好、单井涌水量1000~5000 m3/d、矿化度小于1.0 g/L的地带；土源热泵适宜、较适宜区占调查区总面积的68.57%，主要分布于黄河两岸III~IV级高阶地区与黄土丘陵过度地带及和平、定远盆地等包气带细颗粒地层厚度大于20~40 m、地下水位埋深大于25 m的地带；调查区其余地带不适宜浅层地温能的建设。评价结果对兰州市中心城区浅层地温能的开发利用具有重要的指导作用。 Based on the actual survey data and the test data, the shallow geothermal energy of Lanzhou city center (the area of 384.7 km2) is evaluated and classified by the way of analytic hierarchy pro- cess (AHP). In the evaluation system, 3 criteria and 10 indicators are established for underground water source heat pump, 3 criteria and 8 factors for soil source heat pump, all levels of judgment matrix are constructed and precision through consistency checking. The results show that the area of underground water source heat pump suitable and suitable for the survey area with a total area of 38.99%, which mainly distributed in the fault basin, Yellow River level I - III and the large parts basin of Heping and Dingyuan that the water rich water content is better, the single well water inflow 1000 - 5000 m3/d, the mineralization degree is less than 1.0 g/L. The soil source heat pump suitable and suitable areas for 68.57% of the total area of the survey area, which mainly distributed on both sides of the Yellow River level III - IV higher-order region and the Loess Hilly transition zone, Heping and Dingyuan basin, which aeration with fine grain layer thickness is greater than 20 - 40 m, groundwater depth more than 25 m. The rest of the survey area is not suitable for the construction of shallow geothermal energy. The research results have an important guiding role for the development and utilization of shallow geothermal energy in the central urban area of Lanzhou city.