青海煤矸石的地球化学特性及对枸杞土壤的致肥作用

Qinghai Coal Gangue Geochemical Features and Fertilization on Chinese Wolfberry Soil

以青海煤矸石为研究对象,使用X射线荧光光谱仪(XRF)和电感耦合等离子质谱仪(ICP-MS)对煤矸石的主、微量元素进行测试,分析其含量的分布特征。研究结果表明:青海矸石样品主要为黏土岩类,少部分为砂岩类,与大陆地壳以及我国其它各聚煤区代表性矸石相比,相对富集主量元素Al_(2)O_(3)、K_(2)O,因此导致类质同象替代的微量元素Ga、Li、Pb以及B含量也比较高。枸杞是喜钾植物,对比分析中发现宁夏枸杞钾含量比青海枸杞高一个数量级,主要原因是宁夏土壤中钾含量比青海土壤中钾含量高一个数量级,而作物(包括枸杞)对K的吸收,超过80%来源自土壤母质,而非施用肥料;因此可考虑将富钾的青海煤矸石作为种植枸杞的施肥土壤。进一步研究发现青海大柴旦矸石中所含农作物生长必须的微量元素(K、Fe、Mn、B、Zn、Cu)较为丰富,重金属元素Cd、Cr、Cu、Hg、Pb、Zn等均未超标,可以考虑直接制成肥料进行利用。

Taking the Qinghai coal gangue as subject investigated,using X-ray fluorescence spectrometer(XRF)and inductively coupled plasma mass spectrometer(ICP-MS)have carried out tests for major and trace elements in coal gangue,and analyzed their content distribution features.The result has shown that the gangue samples from Qinghai have mainly claystone type rocks and a small part of sandstone type rocks.Comparing with continental crust and representative gangues from else coal accumulation regions in China,relatively enriched major elements have Al,K and O(Al_(2)O_(3) and K_(2)O),thus caused isomorphic substitution trace elements Ga,Li,Pb and B contents also rather high.Chinese wolfberry is a kind of potassiumphilous crop;comparative analysis has found that potassium content in Ningxia wolfberry is higher than in Qinghai wolfberry an order of magnitude,the causation is potassium content in Ningxia soil is also higher than in Qinghai soil an order of magnitude.While crops(including wolfberry)absorption of K,over 80%is from soil parent material,not from fertilization.Thus potassium rich Qinghai coal gangues can be considered as wolfberry planting fertilization soil.Further study has found that coal gangues from Da Qaidam,Qinghai contain rather abundant crop growth necessary trace elements K,Fe,Mn,B,Zn and Cu,while heavy metal elements Cd,Cr,Cu,Hg,Pb and Zn none of them overproof,thus can be considered directly made into fertilizer and used.