Method for repairing lead and zinc polluted soil by utilizing accumulator plants-ryegrass and pig manure

Abstract

The invention discloses a method for repairing lead and zinc polluted soil by utilizing accumulator plants-ryegrass and pig manure. The method comprises the following steps of: mixing the pig manure with the lead and zinc polluted soil; planting the ryegrass; fully uniformly mixing the pig manure with surface layer polluted soil under the condition that the applied concentration of the pig manure is 20-80g/kg; absorbing lead and zinc in the lead and zinc polluted soil through the root parts of the ryegrass; transferring the lead and the zinc to the overground parts of the ryegrass; when the overground parts of the plants are mature and can be harvested, moving away the plants from the polluted soil so as to achieve the purpose of removing lead and zinc pollution from the soil. As the ryegrass is good in regeneration capability and high in growth speed and can be repeatedly harvested without complex management, the energy consumption is low, the operability is good, the ecological safety is high, the environmental physicochemical property cannot be destroyed, the secondary pollution cannot be caused, a soil structure cannot be destroyed and polluted, the fertility improvement capability cannot be influenced, and the repair expense is further reduced.

Description

technical field [0001] The invention relates to the technical field of phytoremediation of polluted environment, and particularly relates to a method for quickly remediating lead and zinc pollution in soil by using the enriched plant ryegrass combined with pig manure, through the phytoremediation technology combined with improvers. Background technique [0002] There are usually two ways for heavy metals to pollute soil: one is the environmental pollution caused by metal mining activities. Serious soil; heavy metal polluted soil caused by leaching and other reasons during the stacking of mining waste rocks; soil pollution caused by mine wastewater containing high concentrations of heavy metals, etc. The second is heavy metal polluted soil caused by industrial sewage irrigation of farmland. [0003] Lead is a cumulative poison. Lead in the soil can be absorbed by organisms and transferred to organisms, while humans ingest lead and zinc through the food chain. Lead can inva...

AI Technical Summary

Problems solved by technology

Soil chemical leaching is one of the effective means to effectively treat soil polluted by volatile heavy metals. Choosing a suitable extractant is the key to this technology. However, no matter what kind of extractant, there are problems such as recovery and secondary pollution that have not been solved or perfected. technical problems; electrodynamic restoration is especially suitable for low-permeability clay and silt soil, and is economically reasonable, but due to the complexity of soil system components, there are often phenomena that are contrary to the actual application and experimental results, such as soil buffer performance, components, The composition of ions and the type of polluted metal ions will affect the effect of electrodynamic restoration. The metal electrode itself is easily corroded, and it will also cause secondary pollution of the soil. The disadvantage of electrothermal restoration is that the organic matter and structural water of the soil are easily destroyed. It takes a lot of energy to drive away soil moisture; the soil improvement method is effective for small areas of soil, but it is not suitable for large-scale soil pollution control, and there are still problems in properly handling the replaced soil to avoid secondary pollution; solidification The technology has a certain effect, solidifying heavy metals in situ, which greatly reduces the cost, but it also has certain limitations: it only changes the existing form of heavy metals in the soil, and it is not well understood about the long-term stability of the soil and its impact on the ecosystem. research in this area