RE-cycling

RE-cycling
Photo by Andrea Begoni

Tuesday, 16 December 2014

Recycling: yes or not?

Incineration

Back again on RE-cycling!
Let's restart the debate that I started few posts ago. Today it is time to talk about the incinerations’ impact.

Incineration consequences are involved in two main fields: global warming and human health. In both cases, the original factor that needs an accurate analysis is the gas emissions. Despite the combustion of waste does not release methane, in terms of global warming incineration is problematic because of the amount of CO2, N2O and NH3 emitted ("Good Practice Guidance and Uncertainty Management in National Greenhouse Gas Inventories" IPCC 2000, page 455). Instead, considering humankind health, Daskalopoulos et al. (1997) explain how municipal waste combustion released "polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF)" (Daskalopoulos et al. 1997: 226). These are generally known as toxins and they are considered causes of skin and liver diseases as well as cancer. Moreover, the same authors say that also metal compounds, heavy metals and acids gases are a result of waste incineration and also involved in the human health concerns.

However, comparing incineration to landfilling, it is easily noticeable that:
1. gaining and using energy from incineration is easier rather that from landfilling. Indeed, as highlighted in “Incineration of Municipal Solid Waste” report (DEFRA 2013), from incineration there is a substantial gain of usable energy in terms of heat and electricity.
Even though successful attempts have been done, energy recovery from landfilling is in fact a quite expensive procedure and it is mainly discussed as a possibility rather than a convenient and actual opportunity (
Lombardi et al. 2006).
2. intuitively, incineration reduces the volume of waste. This means that less rubbish is thus dispatched to the land. Moreover, the residual bottom ash can 
also be reused in other engineering fields like road building (Incineration of Municipal Solid Waste, DEFRA 2013).
3. as explained in the UK Government report “Waste GHG Inventory Summary Factsheet”, the emissions from landfill represent the biggest amount of Green House Gases concerning the waste management (incineration does not produce CH4). In 2010, 89% of UK waste disposal gases came from land and just a minor part from incineration.
4. finally, another evidence is that water and soil pollution are mainly related to the leachate derived from the 
landfilled waste. Water contamination coming from incineration is minimal (Daskalopoulos et al. 1997).

Keeping in mind the energy recovery concept, I would say that with this post we have learnt why landfilling is at the bottom of the “Waste Hierarchy” and why the incineration is located in a slightly better position.
At this stage, we have to keep climbing the hierarchy as well as keep comparing the different disposal method each other. In the next few posts I should be able to conclude the current discussion and hopefully I will have fully explained the RE-RE-RE importance.

So...see you soon on RE-cycling!

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