A method of remediating heavy metal-contaminated soil using energy plant configuration mode

Abstract

The invention discloses a method for remedying heavy metal contaminated soil by an energy plant configuration mode. According to the method, energy plants with tolerance to heavy metals are selected to be used for constructing plant communities on the heavy metal contaminated soil. In soil contaminated by lead and zinc, the energy plants can fix the heavy metals to the roots through the retention effect of the roots, on one hand, the energy plants can protect themselves from damage caused by the heavy metals or alleviate the damage while grow normally, and on the other hand, the energy plants can prevent the heavy metals from diffusing to surrounding non-mining soil, farmland and water bodies. After the fruits of the oil plants ripen, the fruits can be used for preparing biodiesel by extracting, physical modification and chemical processing; after heavy metals in the oil are removed by hydrotreating, the oil can be used as industrial oil; residues can be used as a briquette fuel; thus, the development of new energy resources is promoted.

Description

technical field [0001] The invention relates to a method for remediating heavy metal-contaminated soil, in particular to a method for remediating heavy metal-contaminated soil by utilizing an energy plant configuration mode. Background technique [0002] With the rapid development of economic globalization, the problems of energy shortage and environmental pollution are becoming more and more serious, seriously affecting and threatening human health and survival. Among them, the problem of heavy metal pollution is particularly prominent, lead (Pb), zinc (Zn), manganese (Mn) , Copper (Cu), Cadmium (Cd), Chromium (Cr), Mercury (Hg), Arsenic (As), Nickel (Ni) are common heavy metal pollution elements. It is estimated that the total discharge of heavy metal pollutants in my country is about 9,000 tons, and the amount of food polluted by heavy metals is as high as 12 million tons every year, causing direct economic losses of more than 10 billion yuan. Due to the hidden, long-ter...

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Problems solved by technology

However, there are certain limitations in engineering and physical and chemical remediation technologies, such as high cost, difficult management, easy to cause secondary pollution, and large disturbance to the environment. The advantages of destroying the ecological environment are called the real "green restoration technology", which has become the main force and the focus of attention in the control of environmental pollution

[0004] The current phytoremediation technology mainly focuses on the extraction of heavy metals by hyperaccumulator plants, but there are the following problems: (1) The resources of hyperaccumulator plant varieties are insufficient, the selection and cultivation cycle is long, and it is difficult to obtain large-scale utilization and adaptability in a short period of time. (2) Singleness, hyperaccumulator plants have a certain selectivity for heavy metals, that is, generally only have hyperaccumulation ability for one or two kinds of heavy metals, but the actual situation is that most of the polluted soils are Several heavy metals are combined to pollute, so it is difficult for a single plant to fully purify multiple pollutants in the soil; (3) The biomass of the hyperaccumulator plants currently used is generally small, and the overall removal rate of heavy metals is still very low; (4) The current The resource utilization degree of hyperaccumulator plants is low, and the follow-up treatment method of restoration plants is usually to remove or incinerate the whole plants. Phytoremediation materials have no utilization value, and this method does not fundamentally remove heavy metal ions from the environment The heavy metal ions enriched in plants will return to the environment or soil or transfer the pollution to other areas, resulting in secondary pollution; (5) From the perspective of application, the utilization of hyperaccumulator plants is still in the experimental stage. In the stage of laboratory and pilot test, it cannot be cultivated and applied in a large area.

[0005] At present, the reported application of energy phytoremediation of heavy metal-contaminated soil has few plant species and insufficient diversity. issues of sustainability

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