There are a number of different waste treatment technologies for the disposal,

recycling Recycling is the process of converting waste materials into new materials and objects. The recovery of energy from waste materials is often included in this concept. The recyclability of a material depends on its ability to reacquire the p ...

, storage, or

energy recovery Energy recovery includes any technique or method of minimizing the input of energy to an overall system by the exchange of energy from one sub-system of the overall system with another. The energy can be in any form in either subsystem, but mos ...

from different

waste types Waste comes in many different forms and may be categorized in a variety of ways. The types listed here are not necessarily exclusive and there may be considerable overlap so that one waste entity may fall into one to many types. * Agricultural w ...

. Each type has its own associated methods of waste Management

Landfill

Municipal solid waste Municipal solid waste (MSW), commonly known as trash or garbage in the United States and rubbish in Britain, is a waste type consisting of everyday items that are discarded by the public. "Garbage" can also refer specifically to food waste, ...

consists mainly of household and commercial waste which is disposed of by or on behalf of a local authority. Landfills waste are categorized by either being hazardous, non-hazardous or inert waste. In order for a landfill design to be considered it must abide by the following requirements: final landforms profile, site capacity, settlement, waste density, materials requirements and drainage.

Incineration

The advantages of the incineration are reduction of volume and mass by burning, reduction to a percentage of sterile ash, source of energy, increase of income by selling bottom ash, and is also environmentally acceptable.
The disadvantages of incineration are the following: * higher cost and longer payback period due to high capital investment * since incineration is design on the basis of a certain calorific value removing paper and plastics for recycling lowers the overall calorific value that may affect the incinerator performance * the process still produces a solid waste residue at the end which still requires treatment and management Emissions from incinerators consist of particulates, heavy metals, pollutant gases, odor dust and litter. Due to incomplete combustion, products such as

dioxin Dioxin may refer to: * 1,2-Dioxin or 1,4-Dioxin, two unsaturated heterocyclic 6-membered rings where two carbon atoms have been replaced by oxygen atoms, giving the molecular formula C4H4O2 *Dibenzo-1,4-dioxin, the parent compound also known as ...

s and

furan Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen atom. Chemical compounds containing such rings are also referred to as furans. Furan is a colorless, flammable, highly ...

s are formed.

Bioremediation

The human sewage and the process waste from the manufacturing industries are the two major sources of the waste water. In Thailand, the total volume of the wastewater from industries is much greater than that of the domestic sewage. As a result, an effective method is needed. Microbial remediation of xenobiotics has shown to be effective and the low-cost technology, but it still has several limitations. Consequently, the genetic engineering approaches are used to create the new strain of microbes (Genetically engineered microorganisms, GEMS) which have better catabolic potential than the wild type species for

bioremediation Bioremediation broadly refers to any process wherein a biological system (typically bacteria, microalgae, fungi, and plants), living or dead, is employed for removing environmental pollutants from air, water, soil, flue gasses, industrial effluent ...

. There are four major approaches to GEM development for the bioremediation application which include the modification of enzyme specificity and affinity, pathway construction and regulation, bioprocess development, monitoring and control and lastly, bio-affinity bio-receptor sensor application for chemical sensing, toxicity reduction and end point analysis. These allow the extensive use of genetically engineered microorganism. In the far future, the genetically engineered microorganisms could possibly be used to control the green house gases, convert the waste to the value-added product as well as to reduce and capture the carbon dioxide gases from the atmosphere (

carbon sequestration Carbon sequestration is the process of storing carbon in a carbon pool. Carbon dioxide () is naturally captured from the atmosphere through biological, chemical, and physical processes. These changes can be accelerated through changes in land ...

), but much research is still required to realise the potential. There is a concern regarding the use of genetically engineered microbes for the remediation of pollutants. Once the genetically microorganisms has been added, it may disperse uncontrollably and hard to be removed.

Pyrolysis

Pyrolysis is thermochemical conversion process in which the feeding material is converted into char, oil and combustible gas in an inert atmosphere (complete absence of oxidizing agent).

Landfill

Incineration

Bioremediation

Pyrolysis

References

See also