Composite heavy metal polluted soil improver and its application and application method

Abstract

The invention discloses a composite heavy metal polluted soil conditioner as well as application and an application method thereof. The soil conditioner comprises the following components: plant ash, calcium magnesium phosphate, quicklime, zeolite and organic fertilizers at a weight ratio of (0.3-1.1):(0.1-1.2):(0.4-2.1):(0.1-0.6):(0.008-0.06):(0.4-1.2). Through inorganic components such as quicklime, calcium magnesium phosphate and phosphate in hydroxyapatite as well as potassium carbonate in the plant ash, the soil conditioner can be used for fixing heavy metals in polluted soil and improving the fertility of the polluted soil in combination with organic manures such as the plant ash and the organic fertilizers so as to continuously intensify the restoration of the polluted soil, has the advantages of relatively-high stability, good environmental friendliness and low cost, can be used for inactivating and restoring various heavy metal polluted soil, especially has a good restoration effect on soil pollution caused by waste slag discharged by industrial and mining enterprises, can be used for realizing the treatment goal without generating secondary pollution, and is liable to realize large-area popularization.

Description

technical field [0001] The invention relates to the technical field of heavy metal polluted soil treatment, and particularly discloses a composite heavy metal polluted soil improver and its application and application method. Background technique [0002] With the increase of my country's population, the promotion of urbanization and the improvement of people's material living standards, the demand for various products processed and produced by industrial and mining enterprises has also increased rapidly. Harmful heavy metals (such as Cr, Cd, Pb, As, etc.) discharged into the environmental soil continue to increase, seriously destroying the natural ecological environment and threatening people's health, so the treatment of polluted soil is imminent. [0003] The heavy metals that pollute the soil mainly include mercury (Hg), cadmium (Cd), lead (Pb), chromium (Cr) and metalloid arsenic (As) and other elements with significant biological toxicity, as well as zinc (Zn) and coppe...

AI Technical Summary

Problems solved by technology

[0005] Phytoremediation is recognized as an ideal in-situ soil treatment technology, but there are obvious disadvantages: hyperaccumulator plants tend to be short in size, low in biomass, slow in growth rate, and long in growth cycle; most hyperaccumulator plants can only accumulate certain Heavy metals, not suitable for complex heavy metal contaminated soil remediation; phytoremediation is limited by environmental conditions such as soil type, temperature, humidity and nutrition

The alien soil method will destroy the properties of the natural soil, and may also affect the safety of groundwater; the leaching method requires the soil to have relatively high permeability, and at the same time, the residual leaching agent will cause secondary pollution; the heat treatment method has low repair efficiency and high economic investment, there is also the emission of toxic gases and changes in the basic properties of the soil; the electrolysis method is limited by the characteristics of the soil, and is not suitable for soils with good permeability and poor conductivity

Generally speaking, although physical methods can remove heavy metals from polluted soil more thoroughly, they are costly and are not suitable for use on soils with large polluted areas, and are likely to damage soil structure and soil fertility, and cause secondary pollution