*9.6.1 Ways to dispose of nonbiodegradable waste*

Not all waste fits into the criteria of reuse or recycle. These waste needs to be disposed off in a way to have minimal impact on the environment. Disposal of biodegradable waste is very simple and can be done employing easy methods like landfilling, composting, etc.

The NBW cannot be decomposed naturally and need special disposal techniques for minimizing hazardous effects on environments and people handling it. Let us look at some nonbiodegradable waste management methods commonly used.

#### *9.6.2 Incineration*

Usually used for nonrecyclable nonbiodegradable waste and bio-hazardous waste from hospitals, etc. Incineration involves decomposition by combustion of waste using high heat, i.e. above 500°C. It is also referred to as the thermal treatment of waste. Incineration of waste converts it primarily into ash, flue gas, and heat. Heat can be used for various heat-based processes. The gases and fumes must be treated properly to prevent or at least reduce environmental pollution. Air filters are nowadays employed for the same. Modern methods of incineration such as gasification, pyrolysis, and anaerobic digestion can be utilized for energy recovery. Useful content from the residual ash contains metals that can be recovered using separate treatments. **Table 10** depicts some methods of incineration for waste disposal (**Table 12**).

Incinerators reduce the mass of the waste by 80–85% and the volume by 95–96%, depending on the composition and degree of recovery of materials such as metals from the ash for recycling [53].

### *9.6.3 Landfills*

Solid waste landfill is a separate area of land or excavation where waste is collected. It provides long-term storage for nonbiodegradable waste. Ideally, landfills should be carefully situated and designed to prevent waste contamination from entering the neighboring environment. They are designed to reduce odor and pests to the maximum possible extent.



#### **Table 12.**

*Methods of incineration for waste disposal.*

Sanitary landfills are similar to normal landfills but are built in a planned and methodical way. Normal landfills cannot completely prevent the leaching or leakage of waste and toxic substances along with water into the ground. Sanitary landfills are closed areas built with concrete and with facilities to collect the leachate and gases released. These also are superior in preventing pest breeding and pathogen spread.

Large area requirements, cost and chances of leakage, and pollution are some disadvantages.

### *9.6.4 Plasma arc furnaces*

They are referred to as "plasma recycling," and "plasma gasification. In this process, the waste is heated to super-high temperatures where it melts and then vaporizes producing gas that can be used for energy and rocky solid residue that can be used for various purposes like a building material. Unlike inclinators which convert waste to ash and gases, plasma arc furnaces first directly convert waste to plasma, the fourth state of matter, and then produce gasification. Thus, it's a cleaner, greener form of waste treatment.

### *9.6.5 Encapsulation*

Encapsulation is covering of material with some kind of material uniformly resulting in a product called the capsule. In waste disposal by encapsulation method, the waste is crammed very compactly in an inert cover just like a capsule which does not allow any exchange of materials including gases. These capsules of waste are buried deep down into the ground resulting in safe and long-lasting waste disposal without any leakage, leaching, and contamination of the environment.

At the COP26, world leaders discussed strategies directly affecting climate change. The Centre for Sustainable Healthcare has requested world leaders to take initiatives to make sure that healthcare systems are Net Zero by 2040. They further stated to fund existing healthcare facilities to transfer them to environmentally sustainable healthcare systems. This includes collaboration with all players in the supply chain to de-carbonize medical devices. Reducing plastic medical waste is an essential strategy.

### **9.7 Refuse**

It is the fifth "R" of waste management. Refuse should be the first choice which involves refusing a certain amount of waste production. Refuse means not using or

#### *The Toxicity of Environmental Pollutants*


#### **Table 13.**

*Strategies for HCW management.*

discontinuing use of waste-generating things, especially nonbiodegradable and hazardous things. Refuse can act as the most prominent measure in reducing waste generation. By refusing the usage of certain materials, one can avert the HCW generation thus not requiring any treatment or processing and saving a lot of financial resources, and preventing health and environmental hazards waste. For example, the refusal to single-use plastic in HCI will not only decrease the amount of plastic in HCW but will also prevent the related effects of plastic waste. It can look impractical and difficult, but there are some better and less waste generating options that can be opted for. It's the most effective way to reduce the amount of waste HCI is producing.

The measures are summarized in **Table 13** with enlisting more R's.
