What is in situ and ex situ remediation?
Ex-situ remediation includes removing contaminated soils or groundwater from the subsoil and treating it at the same site or transferring it for cleanup to another location (Tsai et al., 2008). In contrast, In-situ techniques are the processes that directly remove contaminated soil or groundwater from the ground.
What is ex situ soil remediation?
Ex-situ bioremediation is a biological process in which excavated soil is placed in a lined above-ground treatment area and aerated following processing to enhance the degradation of organic contaminants by the indigenous microbial population.
What does in situ remediation mean?
In-situ remediation is a method of breaking down and purifying hazardous substances present in soil and groundwater. It possesses the following characteristics: It is a simple method, involving nothing more than the impregnation of subsurface soil with nutrients that activate microorganisms.
What is the difference between in situ and ex situ bioremediation?
Ex situ remediation techniques involve removing the soil from the subsurface to treat it. In situ remediation techniques involve leaving the soil in its original place and bringing the biological mechanisms to the soil.
What is an example of ex situ?
Examples of ex-situ conservation of biodiversity include aquariums, botanical gardens, cryopreservation, DNA banks, zoos, etc.
What is ex situ soil example?
For example black soil, desert soil etc.
What is in situ and ex situ process?
Hint:In-situ conservation means conserving all the living species, especially all the wild and endangered species, in their natural habitats and environment. Ex-situ conservation means conserving all the living species in the man-made / artful habitats that are similar to their natural living habitats.
What are the methods of ex situ bioremediation?
Ex-situ bioremediation includes bioreactors, where material is put in a large vessel and mixed in a controlled environment; landfarms, where material is laid out in an isolated area and mixed; and biopiles, where material is placed in aerated piles.
Is Vapor Extraction an ex situ remediation?
Soil vapor extraction (SVE) is used to remediate unsaturated zone soil. A vacuum is applied to the soil to induce the controlled flow of air and remove volatile and some semivolatile organic contaminants. It is usually an in situ technology; however, in some cases, it can be used as an ex situ technology.
What's ex situ mean?
Ex-situ definition Outside its original position or place.
What is the meaning of ex situ?
Outside, off site, or away from the natural location. For example, biological material which is in a laboratory, collection, botanical garden, zoo, or aquarium. Also known as off‐site.
What are 2 types of bioremediation?
In-situ bioremediation is two types; these are intrinsic and engineered bioremediation. Intrinsic bioremediation also known as natural reduction is an in-situ bioremediation technique, which involves passive remediation of polluted sites, without any external force (human intervention).
Which soil is ex situ soil?
alluvial soilEx situ soil is the soil that can be carried by different agents and deposited away from the place where it is formed. One such example is alluvial soil.
How is ex situ soil formed?
This soil is formed when the agents of erosion deposit sediment at a place. This soil is formed when the parent rock is broken into small fragments. This soil is formed far away from its parent rock.
What is ex situ bioremediation?
Ex-situ bioremediation describes a process where contaminated soil or water is removed from the environment by biological organisms. Ex-situ bioremediation can use bioreactors and added nutrients to speed up the breakdown of environmental pollutants. Create an account.
What are the advantages and disadvantages of ex-situ bioremediation?
The advantages of ex-situ bioremediation include controlling variables like temperature, aeration, and nutrient level to support biological activity and preventing the contaminant from continuing to spread within the environment. Disadvantages include the difficulty in removing large quantities of contaminated material, and the space and resources needed to effectively treat it.
What is bioremediation in biology?
Bioremediation is a process where biological organisms break down environmental contaminants.
What is the alternative to bioreactors?
When bioreactors aren't used, landfarming or biopiles are alternatives. Landfarming involves spreading contaminated soil into a lined bed (to prevent leaching) and periodically applying nutrients and mixing the soil to boost biological activity.
What is the process of breaking down contaminants?
Bioremediation is a process where biological organisms break down environmental contaminants. When bioremediation takes place in the environment we call it in-situ, and when the contaminated material is removed from the environment and treated elsewhere we call it ex-situ bioremediation. Ex-situ bioremediation includes bioreactors, ...
Can bioremediation be controlled?
When the material is removed from the environment, it can be put into bioreactors, large vessels where the contaminated material can be monitored and conditions for bioremediation can be controlled. Biological organisms typically have conditions where they operate best. In bioreactors we can control the mixing rate, temperature, pH, and nutrient levels to suit the organisms breaking down our contaminant.
Is it easier to in situ or ex situ?
On the face of things it would seem that in-situ bioremediation is a lot easier than ex-situ. We don't have to move around a bunch of contaminated soil or water and set up bioreactors, landfarms, or biopiles. But there are some drawbacks to just leaving everything in place and waiting for the biological organisms to break down the pollutants. Sometimes it can be very slow, the contaminant spreads, or wildlife comes into contact with it.
Ex-Situ Remediation
LCR provides ex-situ remediation services in combination with Bio-Reclaim™ to degrade hydrocarbons. Processing up to 1000 cubic metres per day, soil is excavated and loaded into our Earth Cleaning Machine (ECM), and then returned to a clean liner.
An Alternative to Digging and Dumping
The cost of digging and dumping is high. Ex-situ bioremediation is a cost-effective alternative to remove hydrocarbon contaminants from the environment. We can provide and operate equipment as needed to ensure the safe and effective implementation of bioremediation processes.
What is ex situ bioremediation?
Ex situ bioremediation involves removal of waste materials and their collection at a place to facilitate microbial degradation . Ex situ bioremediation technology includes most of disadvantages and limitations. It also suffers from costs associated with solid handling process e.g. excavation, screening and fractionation, mixing, homogenizing and final disposal. On the basis of phases of contaminated materials under treatment ex situ bioremediation is classified into two : (i) solid-phase system (including land treatment and soil piles) i.e. composting, and (ii) slurry-phase systems (involving treatment of solid-liquid suspensions in bioreactors).
Why is closed treatment preferred over open land treatment?
The closed treatment system is preferred over the open land treatment system because controlled air is supplied to maintain the microbial activity. As a result of microbial growth and volatilization of hazardous compounds, internal temperature gradually rises.
What are the possible routes leading to disappearance of hazardous compounds?
The possible routes leading to disappearance of hazardous compounds include volatilization, assimilation, adsorption, polymerization and leaching (Hogan, 1998). Composting can be done in open system i.e. land treatment, and in closed system.
What are the three types of slurry-phase bioreactors?
Biologically there are three types of slurry-phase bioreactors : aerated lagoons, low-shear airlift reactor, and fluidized-bed soil reactor. The first two types are in use of full scale bioremediation, while the third one is in developmental stage. (i) Aerated Lagoons.
Why are hazardous compounds resistant to microbial degradation?
However, many hazardous compounds are resistant to microbial degradation due to complex chemical structure, toxicity and compound concentration that hardly support growth. Microbial growth is also affected by moisture, pH, inorganic nutrients and particle size.
Does bioaugmentation inhibit microbial growth?
Gradual colonization of organic materials is done by indigenous microflora, but hazardous chemicals may inhibit microbial growth. Therefore, bioaugmentation (i.e. use of commercial or GEMs) of wastes is also recommended.
How does environmental remediation work?
What does environmental remediation accomplish? It begins with removing the physical lead from the area: cleaning out any lead left over from the original source and removing it from the area so that it won’t leech into the soil and groundwater. After that, the soil is treated with our patented ECOBOND® technology, then replaced in the affected area. ECOBOND® removes the lead from the soil and makes it safe for use. MT2 has years of proven success in the bioremediation of many different environments for gun ranges as well as other sites. Contact us to the needs of your project. image source https://en.wikipedia.org/wiki/Biodegradation
How does bioremediation work?
Bioremediation is the act of using organisms such as bacteria and plants in order to naturally get rid of hazardous waste. The idea is that it mimics and enhances the natural process of biodegradation that takes place in the environment. This can be for a variety of purposes and for a number of different materials. It is an important choice and key part of the soil and waste remediation process. Bioremediation of a contaminated site typically works in one of two ways. Ways are found to enhance the growth of whatever pollution-eating microbes might already be living at the contaminated site. In the second, less common case, specialized microbes are added to degrade the contaminants.
What are the advantages of bioremediation?
Some advantages of this type are lower costs, total elimination of the contaminants, and lower risk factor to those around it. This is also less invasive with limited human involvement. That said, the surrounding environment can impact the ability to transform the hazardous materials, and it hast to be monitored closely and consistently.
How does a groundwater remediation system work?
For groundwater remediation, this process typically is conducted in a packed column (or tower) or a low-profile sieve tray aeration system. The typical packed tower air stripper includes: a spray nozzle or manifold at the top of the tower to distribute contaminated water over the packing in the column, a blower to force air countercurrent to the water flow, and a sump at the bottom of the tower to collect decontaminated water. Low-profile sieve tray air strippers are available in horizontal tray (also known as shallow tray) or vertical box designs that are equipped with a series of stacked trays. Baffles and weirs inside the stripper trays are used to route contaminated water two or more times along the length of the tray of the box. Air sparged through the bottom of the tray or through a vent pipe in the bottom of the system passes in a countercurrent direction through the water to strip out VOCs. Typically, the tray-style strippers are modular and trays can be added or removed to properly size the system for flow capacity and stripping efficiency. Packed towers and tray systems are generally designed as single pass systems; however, a portion of the effluent water can be split and recirculated back into the air stripper for the purpose of achieving a higher removal efficiency without the need to increase the height of the packed tower or the number of trays in a low-profile system. Diffused aeration strippers consist of aeration tanks in which VOCs are stripped from the process water by bubbling air into a tank through which the contaminated water flows. A forced air blower and an aeration/sparge manifold are designed to create air-water contact.
What is the difference between a packed tower and a diffused aeration unit?
The selection of a packed tower versus low profile or diffused aeration unit is dependent on flow capacity, influent concentrations, and removal requirements. Low profile and diffused aeration units take up much less space and are easier to maintain. Packed towers offer higher capacities and greater removal capabilities for more complex treatment needs.
Why is GAC treatment needed?
Liquid phase GAC treatment may be needed as a polishing step to meet regulatory limits, which would incur disposal costs for periodic media changeouts. GAC treatment, alone, also could become more cost effective than air stripping later in the treatment life cycle as the influent concentrations and/or pumping rates decrease, which would significantly decrease O&M costs.
What is the difference between in situ and ex situ bioremediation?
The key difference between in situ and ex situ bioremediation lies on the place where the process is carried out.
What are some examples of in situ bioremediation?
Examples of in situ bioremediation technologies include bio-venting, enhanced biodegradation, bioslurping, phytoremediation, natural attenuation, etc.
What is Bioremediation?
Among these, chemicals are in popular use due to its ease of use and immediate results. However, chemical methods are proven to be non-ecofriendly methods since they have negative impacts on land, soil and organisms. Therefore scientists were keen on finding alternative methods which were safe, environmental friendly and sustainable. Bioremediation is such a type of waste management technique which uses biological organisms to alleviate environmental pollution. Bioremediation can be defined as a process which removes or neutralises waste and toxic substances in the environment , using organisms such as microorganisms, small organisms and plants. Many microorganisms and plants are capable of degrading toxic and hazardous substances and reducing the toxicity. Naturally occurring microorganisms decompose the organic waste in the environment by biodegradation.
How does bioremediation work?
Bioremediation is the process which uses biological systems such as microorganisms and plants to reduce or destroy the concentrations of contaminants in the polluted environments. It can be done in two ways: in situ or ex situ. In in situ bioremediation, contaminants are treated at the same site using biological systems. In ex situ bioremediation, contaminants are treated in some other place from the original site. This is the key difference between in situ and ex situ bioremediation. Bioremediation processes are cost effective, safe and nature-based methods over the chemical and physical methods.
What is bioremediation in biotechnology?
Bioremediation is a term used in biotechnology to refer the process of cleaning the polluted areas using biological organisms such as microorganisms and plants. The use of organisms to reduce and transform contaminants into non-toxic substances is an environmentally friendly process which does not negatively affect the environment and organisms. Bioremediation can be done mainly in two methods known as in situ and ex situ. The key difference between in situ and ex situ bioremediation lies on the place where the process is carried out. In in situ bioremediation, contaminants are degraded at the same site where it’s found while the contaminants are treated in a different place in ex situ bioremediation.
What is bioremediation in the environment?
Bioremediation can be defined as a process which removes or neutralises waste and toxic substances in the environment , using organisms such as microorganisms, small organisms and plants.
Is in situ bioremediation feasible?
The manipulation of above factors is not highly feasible in in situ bioremediation. However, in enhanced in situ bioremediation, some manipulations such as aeration, adding nutrients, controlling moisture content, etc. are used to enhance the activity of organisms and increase the rate of degradation.
