Method for restoring soil polluted by heavy metal mercury

Abstract

The invention discloses a method for restoring soil polluted by heavy metal mercury. In a low forest cultivation mode with the extremely high planting density (plant spacing being 0.25-0.35 m), and taking short-cycle harvested leaves and bark as raw materials of gutta-percha, the biomass and the latex yield are increased manyfold by adopting exogenous microbial treatment. Meanwhile, in order to prevent the influence of heavy metals on growth of eucommia ulmoides in the growing early stage of the eucommia ulmoides, soil dressing is adopted for backfill first, then as continuous growing of the eucommia ulmoides, the mercury in the soil is absorbed continuously, and the content of the mercury in the soil is reduced; photosynthetic bacteria are added in the planting process, and the productionspeed is significantly increased; and due to the fact that the elemental mercury is liquid at the room temperature, fluidity is high, in order to prevent loss of the mercury, adsorption materials areadded in the soil, clay has a very good adsorption effect, expanded vermiculite powder is internally provided with a large storage space, the clay and the expanded vermiculite powder are mutually matched, and the adsorption ability and the slow-releasing ability are very good.

Description

technical field [0001] The invention relates to the technical field of soil remediation, in particular to a method for remediating soil contaminated by heavy metal mercury. Background technique [0002] Heavy metals refer to metals with a specific gravity greater than 5 (generally referring to metals with a density greater than 4.5 grams per cubic centimeter). There are about 45 species, generally belonging to transitional elements. Such as mercury, lead, zinc, iron, cobalt, nickel, manganese, cadmium, mercury, tungsten, molybdenum, gold, silver, etc. Although heavy metals such as manganese, mercury, and zinc are trace elements needed for life activities, most heavy metals such as mercury, lead, and cadmium are not necessary for life activities, and all heavy metals are toxic to the human body if they exceed a certain concentration. [0003] For example, the clinical manifestations of mercury poisoning are: general symptoms are headache, dizziness, fatigue, and fever. Sym...

AI Technical Summary

Problems solved by technology

So far, on the one hand, the biomass of arbor forest leaves is insufficient and the harvesting cost is high; on the other hand, the planting area of ​​Eucommia orchards in China is less than 3,000 hectares, and the fruit production cycle is too long. Between 400-800 tons, it is only equivalent to 70-250 tons of eucommia gum annual output; therefore, the lack of total resources (leaves and fruits) of eucommia gum fundamentally limits the development of eucommia gum industrialization