Environmental remediation encompasses the process of decontaminating soil, rock, sediment and groundwater using various technologies. Below are four forms of eco-friendly technologies utilized for environmental remediation.

 

1. Thermal desorption

 

In this method, heat is applied to excavated soil within an enclosed container. The semi-volatile organic compounds (SVOCs) and volatile organic compounds (VOCs) are turned into vapors, which are then collected in a chamber. These vapors are once again treated by heat to convert them into carbon dioxide or water, or to destroy them. Substances that cannot be vaporized undergo more rigorous treatment. 

This method of environmental remediation can also be used to remove fuels, pesticides and some metals from soil.

 

2. In situ oxidation

 

In situ oxidation involves pumping oxidants through a contaminated region to create chemical reactions that will produce harmless byproducts. A catalyst, such as an iron catalyst, can be used to increase the reactivity of a certain chemical such as hydrogen peroxide.

A few types of oxidants that can be used include potassium permanganate, ozone gas, or hydrogen peroxide. This method is useful for the remediation of soil or groundwater.

 

3. Surfactant enhanced aquifer remediation (SEAR)

 

Environmental remediation using the SEAR method requires injecting a contaminated area with a chemical solution and pumping out the waste from the point of extraction. Depending on how large the contaminated site is, multiple injection and extraction points may be necessary to ensure complete coverage.

The contaminated site is typically injected with surfactants, which are hydrocarbon mitigation agents, to enhance the water solubility of organic contaminants and reduce the interfacial tension between two immiscible liquids.  

 

4. Nano remediation

 

In nano remediation, the contaminated site is directly injected or treated with small-sized particles to cause redox reactions, degrading the organic contaminants. Nanoparticles are also effective in immobilizing toxic metals such as arsenic, mercury and lead.In situ nano remediation is used to detoxify pollutants below ground, such as groundwater. 

The potential benefits of this form of environmental remediation include reducing overall costs and cleanup time, as well as eliminating the need for treatment and disposal of contaminated dredged soil.