Soil restoration is the transfer, absorption and drop of physical,
chemical and biological methods.
The main technical principle of the main technology
The pollutant in the solution and the transformation of the soil
can be reduced to the acceptable level or the toxic and harmful
pollutant into harmless material. Fundamentally said that the
principle of contaminated soil remediation technology to include:
(1) change pollutants in the soil of existence form, or the same
soil binding mode, reduce the in the environment of migration and
biological can use; (2) reduce the concentration of harmful
substances in the soil.
U.S. investment in contaminated soil remediation in the twentieth
Century 90's has nearly $100000000000. The theory and technology of
contaminated soil remediation have become the frontier of
environmental science and technology research.. Soil remediation
process is rather long, to solve the problem of soil pollution,
need to have different discipline scientists such as pedology,
agronomy, ecology, biogeochemistry, marine science and involving
agriculture, forestry, fisheries and other related production units
and government decision-making of joint efforts.
The pollution of soil has threatened the sustainable use of land
resources and the ecological security of agricultural products..
The affected by organic pollutants in the farmland has reached 36
million hectares, the types of pollutants including oil, polycyclic
aromatic hydrocarbons, pesticides, organic chlorine; for oil
exploitation caused serious oil pollution land area of 10000
hectares, oil refining industry also make large area of land is
polluted; in Shenyang and Fushun petroleum wastewater irrigation
area, surface and bottom soil PAHs are more than 600 mg / kg,
causing serious pollution of crops and groundwater.
National affected by the heavy metal pollution of land amounted to
20 million hectares, which seriously polluted the land of more than
70 million hectares, which 13 million hectares of land for cadmium
content exceeded and are forced to abandon. Because of this,
China's contaminated soil remediation research is undergoing a
transition from laboratory to practical stage, which is about to
enter a fast and comprehensive management period.
1, thermodynamic repair technology, the use of heat conduction,
heat blankets, hot wells or hot walls, etc., or heat radiation,
radio waves heating and other pollution soil remediation.
2. The thermal desorption technology of the pyrolysis and
absorption of organic matter from the soil heated to the organic
boiling point of the organic matter, so that the organic matter in
the soil can be separated into the gaseous state and then
3 and incineration, incineration of contaminated soil in the
incinerator, the harmful substances of high molecular weight?
Volatile and semi volatile, broken down into low molecular of flue
gas after dust removing, cooling and purification treatment of flue
gas to achieve the discharge standards.
4, landfill method, the waste as a mud sludge applied into the soil
through fertilization, irrigation, adding lime and regulation of
soil nutrition, moisture and pH value to keep the contaminants in
the upper layer of soil aerobic degradation. Soil pH and humidity
can be detected by soil acidity, and soil EC was detected by soil
EC, and the effect of soil amelioration was viewed..
Detection of soil pH
5, chemical leaching, with can promote soil dissolved contaminants
or migration of chemical / biological chemical solvent under the
action of gravity or by the hydraulic pressure drive leaching
liquid is injected into the contaminated soil, and then the
containing pollutants solution is extracted out from the soil, into
the line of separation and wastewater treatment technology.
6, composting using traditional composting method, accumulation of
soil pollution, pollutants and organic matter, rice straw, wheat
straw, wood chips, wood and bark manure mixed together, relying on
the composting process in the role of microorganisms in soil
degradation of refractory organic pollutants.
7, phytoremediation, using agricultural technology improve the soil
on plant growth adverse chemical and physical constraints, to
prepare the ground for planting, and the optimization of planting
plants and Rhizosphere Microorganism directly or indirectly,
volatile, separation, degradation of pollutants, restore to build
natural ecological environment and vegetation landscape.
8, permeable reactive barrier is a kind of in situ processing
technology, in the shallow layer of soil and groundwater, build a
of permeability, containing the walls of reaction materials, water
pollution through the wall in reactions where the contaminants and
wall material occurs physical and chemical reaction was purified.
9, bioremediation, using biological, especially microbial degrad