摘要
为了探讨污泥发酵物对水基钻屑人工土壤形成的作用机制,设计了水基钻屑与污泥发酵物质量比分别为10∶1、10∶2、10∶4、10∶6、10∶8和水基钻屑对照(CK) 6个试验处理,采用紫穗槐种植试验对水基钻屑人工土壤的理化性质和重金属风险特征进行了研究。结果表明,污泥发酵物显著降低了人工土壤的pH值、电导率(EC),降低幅度分别为6. 82%~11. 36%、58. 18%~61. 39%;污泥发酵物显著增加了人工土壤的碱解氮、有效磷和有机质质量比,且随污泥发酵物增加呈上升趋势;污泥发酵物降低了人工土壤中Hg、As、Cr、Zn、Ni质量比,但增加了Cd、Pb、Cu质量比。重金属生态风险评价结果显示,所有处理的重金属均处于低等生态风险水平(RI=13. 57~31. 13 <150),其中Cd、Hg对人工土壤重金属综合生态风险指数贡献率较大,Cd是污泥改良水基钻屑实施土壤化利用的重点控制因子。紫穗槐对Zn、Cu、Hg、Cd具有明显富集作用,但当水基钻屑与发酵物的质量比达到10∶8时会抑制紫穗槐茎的生长。综合研究表明,污泥发酵物可使水基钻屑人工土壤的pH值、EC、养分及重金属含量满足CJ/T 340-2016《绿化种植土壤》标准要求,建议污泥发酵物的适宜添加量为10%~20%。
The present paper is aimed at study and discovery of the physicochemical properties and heavy metal risk features of water-based drilling cuttings (WBDC) artificial soil through an experiment with planting Amorphous fruitcose so as to investigate and find the action mechanism of municipal sludge fermentation products to WBDC artificial soil formation. In the paper,we have laid out 6 groups of treatments in the experiment,in which the weight ratio of WBDC to the sludge fermentation products can be found in the following ratios: 10: 1,10: 2,10: 4,10: 6,10:8,respectively,with the WBDC being treated without any sludge fermentation products. The results of our experiments show that the sludge fermented products can help lower the pH value and the electrical conductivity (EC) of the artificial soil significantly in a range of 6. 82%-11. 36% and 58. 18%-61. 39%,respectively,but they can also increase the mass ratio of the available nitrogen,phosphorus and some more organic matters of the artificial soil obviously with the increase of the sludge fermentation products. Besides,it has also been found that the sludge fermentation products can help not only reduce the mass ratio of the heavy metal contaminants,like those of mercury,arsenic,chromium,zinc and nickel of the artificial soil,but can they also increase the mass rato of cadmium,lead and copper. In addition,the ecological risk assessment for heavy metals suggests that the comprehensive heavy metal ecological risk indexes (RI =13. 57-31. 13 < 150) of all the 6 conducted treatments should be put into the low-level category. On the other hand,the contribution rates of the comprehensive ecological indexes of Cd and Hg prove to be higher than those of the other 6 heavy metals,with the content of Cd being the key factor needed to be controlled when the sludge fermentation products were acting as the modifier of the WBDC artificial soil. Moreover,planting of the Amorpha fruticose may have an important effect in enriching Cu,Zn,Hg,Cd to their own tissues,though it may restrain and restrict the growth of the stems of Amorpha fruticosa to the weight ratio of WBDC to the sludge fermentation products of 10: 8.Therefore,the sludge fermentation products can be concluded helpful to improve the basic physicochemical properties of the artificial soil of WBDC,which can help the pH value,the EC,the nutrient and the heavy metal contents so as for them to meet the standard of CJ/T 340—2016 Planting Soil for Greening. And,last of all,10%-20% of the sludge fermented products can be said quite enough for the WBDC land application.
作者
张思兰
张春
陈科平
周泽军
梅绪东
熊德明
ZHANG Si-lan;ZHANG Chun;CHEN Ke-ping;ZHOU Ze-jun;MEI Xu-dong;XIONG De-ming(Chongqing Fuling Shale Gas Envoironmental Protection Research and Technical Service Center,Chongqing 408000,China;Chongqing Shale Gas Development Environmental Protection Engineering Technology Research Center,Chongqing 408000,China;Jianghan Oilfield Branch Company,SINOPEC,Qianjiang 433124,Hubei,China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2020年第3期1061-1069,共9页
Journal of Safety and Environment
基金
重庆市社会事业与民生保障科技创新专项(cstc2017shms-zdyfX0033)。
关键词
环境工程学
水基钻屑
生活污泥发酵物
土壤化利用
重金属
紫穗槐
environmental engineering
water-based drilling cuttings
municipal sludge fermentation products
land application
heavy metal
Amorphous fruticosa
