From time immemorial, waste disposal has been a challenge for civilizations, and after industrialization, the problem has only exacerbated. In the past, when the consumption of products was low, trash was carried to the outskirts of cities and discarded in the open, but that can no longer be done now. Today, various waste disposal methods have been devised, like compost, burning, landfill etc. Let us take a look at some of these methods of waste management.
CompostYou can create a compost in your own house to dispose off organic wastes. Ideally this should be in everyone's homes as waste materials like branches and leaves can be easily disposed off. More importantly, compost is beneficial for the environment as unnecessary refuse is not dumped into a landfill. This goes a long way in ensuring that methane - a greenhouse gas, is produced in lesser volume in the landfills. Rather than throwing away leaves and other household organic matter, you should use them as compost. This will help in replenishment of soil, thereby reducing cost of land reclamation.
Open BurningOpen burning of solid waste greatly reduces its volume, thereby decreasing the stress on a dumpsite. Open burning has remained one of the widely practiced methods of waste management. However, open burning releases toxic gases directly into the atmosphere and has many negative effects on our environment. The poisonous gases that are released into the atmosphere are harmful for humans as well as other animals. They affect the respiratory and reproductive system, and therefore, this sort of waste management is discouraged and other methods in which the release of poisonous gases in the atmosphere is controlled should be opted for.
IncinerationIncineration is a process in which the waste material is subjected to intense heating in the presence of oxygen inside a incinerator (furnace), resulting in the production of ash, flue, and gas. Incineration doesn't exactly destroy all the waste, instead it decreases the volume of the waste by 60-70%. This compressed waste can then be buried in earth through the process of landfilling. Although incinerators are used all over the world, public opposition to these have been growing as new research has claimed that the gases produced during this process pose greater danger to the environment than the waste materials.
Pyrolysis and GasificationPyrolysis works on the same methodology as incineration, i.e. burning solid waste at high temperatures to compress its size. Pyrolysis differs from incineration in the aspect that solid waste is burned in the absence of oxygen. Gasification, on the other hand, allows a low supply of oxygen to convert waste into combustible and non-combustible gases along with some liquids. The end material can then be used as heat energy, and the leftover waste can then be taken for landfilling which will take comparatively lesser space.
Landfilling and DumpsLandfills and dumps are used to store waste materials beneath the soil. In many cases, remnants of waste material are not disposed even during the process of incineration, pyrolysis, and gasification. These waste materials are transported to landfills and dumps, where these are buried under the soil. Care is taken to ensure that leachate (liquid waste) doesn't permeate through and pose a threat to the environment. Many landfills/dumps are also designed in such a way that energy released during the process of decomposition of waste is tapped and used for generating power. Decomposition of waste takes a lot of time which, in turn, affects the refilling of landfills/dumps. However, with the introduction of bioreactor landfills, this challenge has been tackled to a large extent.
Disposal of Hazardous Waste MethodsSome of the most common waste disposable methods include incineration, composting and landfills. However, disposal of hazardous wastes in landfills and incinerators has its own concerns, especially leaking of toxins into surrounding groundwater. A major source of drinking water is groundwater and if that becomes contaminated, it becomes extremely costly and difficult to purify it. Ideally, hazardous substances should be converted into non-hazardous form. To achieve this, several new technologies like high-temperature plasma torch have come up which are able to convert hazardous wastes like low-level radioactive wastes to glass which is environmentally safe.
Incineration is also used to dispose off hazardous wastes, wherein these refuse is changed into inorganic by-products, water and carbon dioxide. However, the costs associated with burning hazardous wastes is high besides difficulty in disposal of wastes.
Bioremediation is another process which is used to dispose off hazardous wastes and convert them into nontoxic products. The process includes the use of natural degradation processes and microorganisms. However, this process requires a long time and at times it becomes difficult to control the process of natural degradation.
Thus, there are numerous waste disposal methods of which landfills and burning are the most common. We should all try to minimize the amount of wastes we produce every day so that we don't exert pressure on the environment. Moreover, the cost associated with disposing off wastes runs into millions of dollars, so, it is better that we adopt the policy of reduce, reuse, and recycle.