Waste Management

 

Waste management                                                                                                   - Divyanshu Singh

Waste management refers to the various schemes to manage and dispose of wastes. It can be by discarding, destroying, processing, recycling, reusing, or controlling wastes. The prime objective of waste management is to reduce the amount of unusable materials and to avert potential health and environmental hazards.

Different activities include collection, monitoring, regulation, and disposal. Waste collection services are often provided for free by the local government. The collected wastes are disposed of by various methods, e.g. by landfill compaction and incineration. Solid wastes, most especially, are incinerated to reduce their volume by 80 to 95%, and to convert them into gas, steam, ash, and heat. However, air pollution is a concern when disposing of wastes by means of incineration.

Thus, other means are encouraged, such as recycling, reprocessing, and re-use. Organic wastes, especially those that are biodegradable, are allowed to be decomposed so that they can be used as mulch or compost in agriculture and the methane gas from the biological degradation be collected and used for generating electricity and heat. Liquid wastes, such as wastewater, undergo treatment producing sewage sludge that can be disposed of by incineration, composting, and landfill. Synonym: waste disposal.

Waste Disposal Methods

There are multiple waste management strategies and methods available. These strategies can be combined or rearranged to form a waste management system that fits an organization. Modern waste management strategies are geared towards sustainability. Other alternatives for waste management is to reduce, reuse and recycle waste.

Also known as physical reprocessing, recycling is ideal for the disposal of inorganic waste such as plastic, glass, and metals.Though organic waste such as paper and food can also be recycled, composting would be a better waste disposal method as it converts organic waste into nutrient-rich fertilizer.

Waste to energy or WtE, on the other hand, is the conversion of non-recyclable waste into heat, electricity, or fuel using renewable energy sources such as anaerobic digestion and plasma gasification.

Anaerobic digestion is the biological reprocessing of animal manure and human excreta into methane-rich biogas. Plasma gasification uses a plasma-filled vessel operating at high temperatures and low levels of oxygen to transform hazardous waste into syngas. Another option for disposing of hazardous waste is bioremediation, the treatment of contaminants, toxins, and pollutants through micro-organisms.

Waste hierarchy

The waste hierarchy refers to the "3 Rs" Reduce, Reuse and Recycle, which classifies waste management strategies according to their desirability in terms of waste minimisation. The waste hierarchy is the bedrock of most waste minimization strategies. The aim of the waste hierarchy is to extract the maximum practical benefits from products and to generate the minimum amount of end waste; see: resource recovery. The waste hierarchy is represented as a pyramid because the basic premise is that policies should promote measures to prevent the generation of waste. The next step or preferred action is to seek alternative uses for the waste that has been generated i.e. by re-use. The next is recycling which includes composting. Following this step is material recovery and waste-to-energy. The final action is disposal, in landfills or through incineration without energy recovery. This last step is the final resort for waste which has not been prevented, diverted or recovered. The waste hierarchy represents the progression of a product or material through the sequential stages of the pyramid of waste management. The hierarchy represents the latter parts of the life-cycle for each product.

Approaches

• First approach –  involves looking at waste hauling and disposal records as well as contracts with recycling facilities.
• Second approach – requires a team of internal auditors to identify waste-generating activities through observation and interviews with employees.
• Third approach – is the physical collection, sorting, and weighing of a sample of the organization’s waste. This sample can be a day’s worth of waste or a collection of waste from each department.