This document discusses remediation of oil contaminated sites. It begins by outlining various sources of land and water contamination including oil spills, industrial activities, and agriculture. The effects of oil contamination include environmental damage, health impacts, and agricultural effects. The document then examines several remediation techniques including physicochemical methods like soil washing, soil vapor extraction and solidification/stabilization. Thermal methods such as thermal desorption and incineration and biological techniques including bioremediation, land farming and phytoremediation are also discussed. Key factors to consider when selecting a remediation method include site characteristics, soil properties, and contaminant type and concentration. In conclusion, the document emphasizes the importance of preventing sp

1. REMEDIATION OF OIL
CONTAMINATED
SITES
GUIDED BY PRESENTED BY
THAHZIN SAGEER SISRUDH K.S.
ASSISTANT PROFESSOR UEANECE051

3. SITE CONTAMINATION
 Land Contamination - Environmental Problem
 Contaminants Accumulate -Toxic to Biological Systems
 Treatment and disposal of hazardous wastes carefully
controlled
 Hydrocarbon contamination of land and water is serious
issue since the discovery of oil

4. SOURCES1.Pesticide
2.Fertilizers
3.High Traffic Areas
4.Landfills/Garbage
Dumps
Fig 1 Source: www.google.com

5. SOURCES(cont.)5.Fires
6.Industrial/Commercial
Site Use
7.Oil Spills
Fig 2
Source: www.google.com

6. OIL CONTAMINATION
 Every year, about 1.7 to 8.8 million metric tons of oil is
released into the environment
 Crude oil released to land or marine environment is
immediately subject to a variety of physical, chemical and
biological changes
 Removal of the hydrocarbon from soil and from water
surface is an essential practice to prevent site
contamination
 Any remained portion of crude oil in the ground acts as a
permanent source of contamination

7. EFFECTS1. ENVIRONMENTAL EFFECTS
 Oil contamination creates hazards to the local
environment
 water, soil and air have been severely tainted by petroleum
pollutants
 As a result, wildlife, livestock, and humans have been
sickened
 Oil contamination has adversely affected the lives of many
people living in areas near oil exploration sites

8. EFFECTS(cont.)2. HEALTH EFFECTS
 One of the largest problems caused by the oil waste is
pollution seeping into the water supply of the
communities in the area
 People have gotten horrible rashes and sores on their skin
from bathing in water that is severely contaminated by oil
 People who live near oil pits, have been struck with cancer
of the stomach, rectum, skin, soft tissue, kidney, cervix,
and lymph nodes

9. EFFECTS(cont.)
3. AGRICULTURAL EFFECTS
 serious damage on the physiological, anatomical and
growth performance of plants, soil components and aquatic
ecosystems
 Sustainable use of agricultural soil on which plants depend
is absolutely necessary for agricultural productivity
 creates unsatisfactory conditions for plant growth probably
due to insufficient aeration of the soil
 Oil readily penetrates the pore space of terrestrial
vegetation following any spill with heavier friction which
may block the pores and this subsequently impedes
photosynthesis and other physiological processes in plant

10. REMEDIATION
 Remediation means the management of the site in order to
prevent damage to human health or the environment and
restoring all or part of the site to a useful purpose
 There are physical, chemical, thermal and biological
techniques available for treating contaminated sites
 All these techniques can be successfully applied if the
physicochemical properties of pollutants and soil particles
are well understood before selecting any method

11. PHYSICO-CHEMICAL
METHODS
1.SOIL WASHING
 Ex-situ remediation technique
 Washing the soil with a liquid,scrubbing the soil
 Separation of contaminated fines and wash water from
cleaned course grained soil
 Important factor affecting this process is the percentage of
fines in the soil

12. METHODS
(cont.)
Fig 3: Schematic diagram of soil washing
(source: http://rscottish-scientists-export-
remediation)

13. PHYSICO-CHEMICAL
METHODS
(cont.)
2. SOIL VAPOUR EXTRACTION
 Also known as soil venting or vacuum extraction
 Involves installation of vertical or horizontal wells in the
area of contamination
 removes volatile and semi-volatile contaminants from the
unsaturated zone by applying a vacuum connected to a
series of wells

14. METHODS
(cont.)
Fig 4: Soil Vapour Extraction Process
(source: www.researchgate.net)

15. PHYSICO-CHEMICAL
METHODS
(cont.)
3. SOLIDIFICATION/ STABILIZATION
 “Solidification” refers to a process in which materials are
added to the waste to produce an immobile mass
 “Stabilization” refers to converting a waste to a more
chemically stable form
 Method always includes use of physicochemical reaction
to transform the contaminants to a less toxic form

16. PHYSICO-CHEMICAL
METHODS
(cont.)
 encapsulates hazardous waste into a solid material of high
structural integrity
 2 Types:
 Asphalt Batching:incorporates petroleum-laden soils into
hot asphalt mixtures as a partial substitute for stone
aggregate
 Vitrification:uses a powerful source of energy to ‘melt’
soil or other earthen materials at extremely high
temperatures, immobilizing most inorganics and
destroying organic pollutants by pyrolysis

17. PHYSICO-CHEMICAL
METHODS
(cont.)
4. AIR SPARGING
 Air sparging is a process during which air is injected into
the saturated zone below or within the areas of
contamination
 Most effective at sites with homogeneous, high-
permeability soils and unconfined aquifers contaminated
with VOCs
 the injected air rises through the formation, it may
volatilize and remove adsorbed volatile organic
compounds (VOC) in soils within the saturated zone as
well as strip dissolved contaminants from groundwater

18. METHODS
(cont.)
Fig 5: Air sparging process
(source: www.kweb.com)

19. THERMAL METHODS
1.THERMAL DESORPTION
 The process desorbs (physically separates) organics from
the soil without decomposition
 desorption removes organic contaminants from soil, by
heating them in a machine called a “thermal desorber” to
evaporate the contaminants

20. THERMAL METHODS(cont.)
Fig 6: Thermal desorption process
(source: http://infohouse.thermfg1.gif)

21. THERMAL METHODS(cont.)
2. INCINERATION
 The main goal of incineration is to heat the contaminated
media to temperatures between 870 and 1,200 0C
 Volatilizing and burning halogenated organic compounds
and other compounds that are difficult to remove
 works best for soils with low water content

22. THERMAL METHODS(cont.)
Fig 7: Incineration process
(source: https://www.researchgate.net)

23. THERMAL METHODS(cont.)
3. STEAM INJECTION
 In situ thermal treatment method
 Steam at high temperature and compressed air are injected
into the contaminated soil
 temperature of the injected steam should be higher than
the boiling points 220 °C of the volatile compounds

24. BIOLOGICAL METHODS
1.BIOREMEDIATION
 Technique utilizes the natural biological activity of
microorganisms to transform the toxic components into
less toxic metabolites
 requires the addition of nitrate or sulphate fertilizers to
aid the decomposition of hydrocarbon compounds
 Downsides of bioremediation are:
(1) Restricted to petroleum components that are microbial
degradable
(2) Process take long times for completion

25. BIOLOGICAL METHODS (cont.)
Fig 8: Simplified bioremediation process
(source: http://www.biorem.com/simpli1.gif)

26. BIOLOGICAL METHODS (cont.)
2. LAND FARMING
 Is an above-ground remediation technology that reduces the
concentration of petroleum
 Bacteria selected for breaking down hydrocarbon are added to
the soil to achieve speedy degradation.
 Lighter petroleum hydrocarbons tend to be removed by
evaporation during aeration processes and degraded by
microbial respiration.
 Heavier petroleum hydrocarbons do not evaporate during
aeration but are broken down by microorganisms present in the
soil at the treatment site.

27. BIOLOGICAL METHODS (cont.)
3. BIOPILES
 piling of petroleum-contaminated soils into piles or heaps
and then simulating aerobic microbial activity by aeration
and the addition of minerals, nutrients, and moisture
 Soil characteristics play a major role in the success of bio
piles include texture, permeability, moisture content, and
bulk density

28. BIOLOGICAL METHODS (cont.)
Fig 9: Biopile
(source: http://www.teamanalysis.com)

29. BIOLOGICAL METHODS (cont.)
4. PHYTOREMEDIATION
 Phytoremediation uses plants to clean up contaminated
soils and groundwater
 It mainly outlines the five techniques:
• Rhizofiltration
• Phytoextraction
• Phytotransformation
• Phytostimulation
• Phytostabilization

30. BIOLOGICAL METHODS (cont.)
Fig 10: Phytoremediation mechanisms
(source: http://pubs.sciepub.com)

31. BIOLOGICAL METHODS (cont.)
5. BIOVENTING
 Process injects air into the contaminated media at a rate
designed to:
• Maximize in situ biodegradation
• Minimize off-gassing of volatilized contaminants to the
atmosphere
 Degrades less volatile organic contaminants
 Allows for the treatment of less permeable soils have
studied the optimized performance and effectiveness of in
situ bioventing.

32. BIOLOGICAL METHODS (cont.)
Fig 11: Bioventing process
(source: http://pubs.rsc.org)

33. BIOLOGICAL METHODS (cont.)
6. BIOSLURPING
 New in situ remediation technology
 Combines elements of bioventing and vacuum-enhanced
pumping to recover free product from the groundwater
and soil
 Vacuum extraction removes free product along with some
groundwater
 The reduction in the amount of extracted groundwater and
the ability to extract soil–gas at concentrations minimizes
storage, treatment, and disposal costs, thus reducing
project costs

34. BIOLOGICAL METHODS (cont.)
Fig 12: Bioslurping process
(soure: http://www.teamanalysis.com)

35. FACTORS TO CONSIDER WHEN SELECTING A
REMEDIATION TECHNIQUE
1. SITE CHARACTERISTICS
 Site topography
 Site surface and subsurface structures and utilities
 Site size
 Depth to groundwater and flow direction

36. FACTORS TO CONSIDER WHEN SELECTING A
REMEDIATION TECHNIQUE(cont.)
2. SOIL CHARACTERISTICS
 Grain size
 Total organic carbon
 Soil pH
 Soil moisture
 Soil temperature
 Soil permeability

37. FACTORS TO CONSIDER WHEN SELECTING A
REMEDIATION TECHNIQUE(cont.)
3. CONTAMINANT CHARACTERISTICS
 Extent of contamination
 Contaminant concentration
 Depth of contaminant
 Contaminant biodegradability
 Contaminant volatility

38. CONCLUSION
 Over the years, many remediation methods have been
developed and applied.
 Remediation of oil contaminated environments is difficult
because petroleum is a complex mixture of chemical
compounds
 There exists some chemical and biological methods to control
oil spills, frequently applied are chemical methods because the
chemical remediation of oil spills is faster if compared to
bioremediation.
 Bioremediation is getting worldwide attention, as it can be
more cost-effective and it can selectively degrade the pollutants
without damaging the site

39. CONCLUSION(cont.)
 Removal efficiency depends on the type of oil, type of soil,
weather conditions, penetration depth, and sensitivity of the
location and the toxicity of the chemicals.
 Site characteristics, soil characteristics, and contaminant
characteristics should be considered for selecting the most
suitable remedial method.
 As there is no universal method can be generally applied to
completely remove the oil from contaminated sites, thus, the
preventing oil spills or leakages should be the first concern.
 If oil spills or leakages occur, response should be taken
immediately to minimize the potential environmental
consequences.

40. REFERENCES
 Arezoo Dadrasnia & C. U. Emenike, Institute of Biological Science, University of
Malaya, Kuala Lumpur, Malaysia,” Remediation of Contaminated Sites”.
 Dike Bu,Yong-Gook Jung & Agbo KC(2013),Department of Civil Engineering,
Federal University of Technology, Owerri, Nigeria, Africa, Journal of Civil &
Environmental Engineering, ”Remediation of Used Oil Contaminated Soil: A soil
washing treatment approach”.
 Faisal I. Khan & Tahir Husain(2004), Faculty of Engineering and Applied
Science, Memorial University of Newfoundland, St John’s NL, Canada ,Journal of
Environmental Management 71 (2004) 95–122, “An overview and analysis of site
remediation technologies”.
 Mohammed M Amro(2004), Petroleum Engineering Department, King Saud
University, P.O. Box 800, Riyadh 11421, Saudi Arabia, International Conf. on Water
Resources & Arid Environment ,“Treatment Techniques of Oil Contaminated Soil
and Water Aquifers”.
 Uchechukwu E. Ezeji & Sylvia O. Anyadoh(2007), Department of Biotechnology,
Federal University of Technology, Owerri, Nigeria, Terrestrial and Aquatic
Environmental Toxicology,”Clean up of Crude oil contaminated soil”.

41. THANK YOU…