How to Clean Soil Contaminated With Oil?

The GardenSpring |

If the spill gets into the ground, on gravel, boulders, or crushed stone, it must be fought. Containing and cleaning up spills can be more difficult than collecting the spill in many cases hard Stands and Enclosed Surfaces.

So in this article, you’ll discover how to clean soil contaminated with oil. Let’s start.

The four basic steps in spill cleanup

  • contain the spill
  • contain the spill
  • removal of spills
  • soil remediation

In the case of a spill on the ground, the first step is usually done very quickly Unless it is a large spill. On a large scale, this should only take a few minutes.

First, make sure the area is safe before attempting to clean up the spill. Beware of smoke. And approaching from the wind. Always wear personal protective equipment.

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Control

Turn off the source of the spill. For example, keep drums upright or stop pumps and turn off all sources of ignition. Locate the source of the spill and provide a means of drainage.

Containment

Use absorbent barriers, berms, hoses, or safety items to contain and prevent spills. A major environmental impact. In many cases, there is little or no lateral movement during spills on the ground.

The spill is completed within the first few minutes. Unless the ground is extremely compacted or wet, the water is absorbed directly into the ground.

Cleanup

Large puddles of liquid can be absorbed with pads, pads, or particles. These absorbent materials can be collected and disposed of. The remaining runoff should be covered with a layer of organic material Absorbent material to soak up the remaining liquid.

If soil conditions permit, rakes can be used. This will better distribute the absorbent material. The use of peat mats is recommended for this task.

Restoration

Bioremediation is often used to break down fuels, oils, and other hydrocarbon products.

The restoration process is not a natural process. However, it should be noted that this process is often difficult on the dry soils of Australia. Also, Global peat contains oil-eating bacteria in addition to those already present in the soil and can be used to initiate bioremediation.

Spraying the contaminated soil with a liquid composed of oil-eating bacteria accelerates the cleanup process. This accelerates the natural decomposition of the oil remaining in the soil.

Microorganisms are not expected to be effective below 300 mm. Tillage improves the permeability and supply with oxygen A thick layer of organic matter, global, is necessary to prevent soil moisture loss and ensure bacterial survival. Peat can be applied to contaminated land.

Water the peat before spreading Adsorbent and then again. It is important to keep the area moist until remediation is complete. Depending on circumstances, this may take weeks or months.

How to clean soil contaminated with oil

Chemical methods

Chemical oxidation is an effective method for removing hazardous residues from soils at oil spill sites. The effectiveness of this method is highly dependent on the soil matrix. Fenton’s reagent, a mixture of hydrogen peroxide and iron ions, is used for chemical oxidation.

Hydrogen peroxide is a strong oxidant that produces hydroxyl ions in the Fenton reaction, in which iron ions act as a catalyst. Hydroxyl ions are very strong and effective substances that destroy pollutants present in the soil.

Another effective oxidant for the removal of crude oil from soils is ozone. Ozone is easy to generate, store, and handle and can be treated on-site. Polycyclic aromatic hydrocarbons are more reactive with ozone than alkanes.

The reactivity of polycyclic aromatic hydrocarbons depends on the number of rings, the presence or absence of heteroatoms, and the degree of alkylation.

Ozone is also useful in bioremediation because it produces oxygen during decomposition, which favors the microbiome present in the soil and promotes the growth of microorganisms.

Chemical methods are a quick way to treat contaminated soils but can have serious effects on the soil and surrounding organisms due to chemical leaching and secondary reactions.

Physical methods

Excavation of petroleum-contaminated soil is the fastest and safest method, but not the most advanced or cheapest. The contaminated soil is removed and taken to a suitable landfill for disposal. Samples are also taken from the soil and from the sidewalls of the excavated area to verify contamination.

Another physical method is washing the contaminated soil. Washing with organic solvents such as ethanol-water or ethyl acetate-acetone-water mixtures has removed hydrocarbons from the contaminated soil to a considerable extent.

Soil washing is not only used to treat oil-contaminated soils, but also to remove heavy metals from the soil. The cleaning effect can be improved by the addition of surfactants. Research has shown that both artificial and natural surfactants can be useful for crude oil removal.

For example, the artificial surfactant dodecyl sulfate (SDS) can remove aliphatic hydrocarbons, while the natural surfactants saponin and rhamnolipid can remove polycyclic aromatic hydrocarbons from contaminated soil. This method is really simple and effective, but very slow and expensive.

Transporting contaminated soil to landfills is also a big problem. In addition, surfactants can stick to soil particles, which is dangerous.

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Thermal methods

Thermal stripping/low-temperature thermal desorption/soil stripping involves heating contaminated soil to very low temperatures (200-1000 °F) to accelerate the evaporation and separation of low-boiling contaminants from the soil.

This process allows for the complete or partial decomposition of organic contaminants, depending on the thermal release temperature and the organic compounds in the soil. This method can remove about 90% of the contaminants, but it is very expensive and harmful to the environment.

Another method of removing crude oil from the soil is incineration. The contaminated soil is burned with a high-temperature fire (1600-2500°F). This method is also not environmentally friendly because the volatile and flammable compounds in crude oil pollute the environment.

Biological Methods

Bioremediation is a traditional method that uses living organisms (bacteria, fungi, and plants) to break down toxic substances in the environment.

Bioremediation of petroleum in the soil is a very effective, inexpensive, and environmentally friendly solution. The effectiveness of this method depends on the concentration of hydrocarbons, the properties of the soil, and the composition of the pollutants.

PAHs are the most resistant and toxic group of soil contaminants in crude oil; PAHs are trapped in soil pores and retained in the soil matrix after penetration into the soil.

Therefore, it is very difficult to remove them from the soil. Bioremediation is the most suitable method for removing PAHs from soil because microorganisms and plant roots have easy access to soil pores.

References

Ahmad, A. A. (2020, March 6). Remediation Methods of Crude Oil Contaminated Soil. Iris Publishers. https://irispublishers.com/wjass/fulltext/remediation-methods-of-crude-oil-contaminated.ID.000595.php#:%7E:text=Washing%20with%20organic%20solvents%20such,heavy%20metals%20from%20the%20soil.

Micu, A. (2019, February 1). Oil-contaminated soil made clean, fertile again using just a little bit of heat. ZME Science. https://www.zmescience.com/science/oil-soil-cleanup-88373/

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