Bioremediation- Everything you need to know

We often hear about bioremediation in the field of wastewater. In this post, we will talk about bioremediation. After reading the article, you can answer the following questions:

1. What is bioremediation? Bioremediation meaning.
2. Types of bioremediation, such as in situ bioremediation and ex situ bioremediation.
3. Advantages of bioremediation.

Bioremediation Meaning

Bioremediation is the use of living organisms, primarily microorganisms, to treat environmental pollutants and detoxify them into less toxic forms. This process uses bacteria, fungi, or plants to detoxify pollutants. These organisms grow and eat pollutants by breaking them down into smaller forms through enzymatic reactions. In addition, microbial growth is affected by environmental conditions such as pH, temperature and the presence of oxygen. Therefore, these conditions may also need to be controlled to promote microbial growth.

Bioremediation helps in treating oil spills, industrial discharge, chemical leaks etc. Most of these contaminants are toxic in nature, threatening life forms. Most of the bioremediation processes happen in aerobic conditions. Under Anaerobic condition bioremediation may help in treating recalcitrant pollutants.

Factors of Bioremediation

Control and optimization of microbial population for bioremediation involves many factors. Such as presence of microbial population, presence of contaminants and environmental factors (such as type of soil, temperature, pH, the presence of oxygen or other electron acceptors, and nutrients).

1. Microbial Population: Microbial population isolated from almost any environmental conditions because of their adaptibility and ability to grow. They can grow in presence of oxygen (aerobes), in absence of oxygen (anaerobes). Ligninolytic fungi used for degradation of extremely diverse range of persistent or toxic environmental pollutants. Methylotrophs survives on methane as carbon and energy source.
2. Nutrient: Presence of nutrients in contaminated soil / water supplemented with external nutrients to promote microbial growth.
3. pH, Temperature and Moisture: In order to facilitate the growth of microbes it is possible to adjust the pH, Temperature and Moisture. Although microbes grow in almost all conditions. But, many of them requires narrow range of pH, Temperature and Moisture. Addition of acid/base adjusts pH. Presence of cover helps in maintaining temperature and presence of water regulates moisture.

Types of Bioremediation

Now you can got the glimpse of what is bioremediation. Let’s move on to the types of bioremediation.

1. In Situ Bioremediation
2. Ex Situ Bioremediation

In Situ Bioremediation

In situ bioremediation is the application of biological treatment to the cleanup of hazardous chemicals present in the subsurface, without transporting them to any other site. Growth condition for the microbes is maintain by the use of some minor modifications.

Ex-Situ Bioremediation

Composting is a process by which organic wastes are degraded by microorganisms, typically at elevated temperatures. Typical compost temperatures are in the range of 55° to 65° C. The increased temperatures result from heat produced by microorganisms during the degradation of the organic material in the waste. This requires removal of polluted soil/ water to be treated at designated facility.

Advantages of Bioremediation

1. Less expensive natural way of treatment.
2. Can treat wide variety of contaminants.
3. Treatment doesn’t neccesarily require transporation of contaminated soil/water.
4. No transfer of contaminants from one medium to another for treatment.

Disadvantages of Bioremediation

1. Resulting compounds may be more toxic than parent.
2. Limited to biodegradable compounds.
3. Difficult to extrapolate from pilot scale to full field operation.
4. Takes longer time to eradiate.
5. Regulatary limitation for accepted performance criteria.

References

1. Vidali, Mn. “Bioremediation. an overview.” Pure and applied chemistry 73.7 (2001): 1163-1172.
2. Kensa, V. Mary. “Bioremediation-an overview.” I Control Pollution 27.2 (2011): 161-168.
3. Adams, Godleads Omokhagbor, et al. “Bioremediation, biostimulation and bioaugmention: a review.” International Journal of Environmental Bioremediation & Biodegradation 3.1 (2015): 28-39.
4. Sharma, Shilpi. “Bioremediation: features, strategies and applications.” Asian Journal of Pharmacy and Life Science 2231 (2012): 4423.