Well done! You are at the end of week 4, congratulations. In this week, we have covered the issues of mixed waste treatment, and then in different modules have tried to give you more insights on other special waste fractions, and how one could deal with them. This comprises hazardous waste, health care waste, e-waste, and then plastic waste as well as construction and demolition waste. For mixed waste treatment, we covered the treatment technologies on Mechanical Biological Treatment, incineration and refuse-derived fuel. For the energy recovery options, obviously, the calorific value of the waste is crucial. Waste-to-energy options, specifically incineration, typically come with high investment and operation costs, and a need for sophisticated technologies, but also skills to ensure that flue gas and slag is treated to avoid negative environmental impact. Here, I would also like to refer to the bonus module on a guide for waste-to-energy assessments. In the module on hazardous waste, we covered the extent of the problem and looked at the categories and sources of hazardous waste. We took a look at the whole chain, from manufacturing to recycling or disposal, and have highlighted the importance of segregation of the different fractions of hazardous waste, so that they can effectively be stored and treated appropriately. Regarding health care waste, it is essential to remember that only a small part, 15 to 25 percent of the waste produced in health care centers, is actually hazardous or infectious. Also here, it is therefore crucial to ensure a good segregation at source - before then treating only the problematic fractions. We covered some segregation and storage systems as well as some treatment options. Regarding e-waste, you should now have an idea of the extent of the problem around e-waste. What is important to remember is that most e-waste recycling is now happening in low- and middle-income settings, and the threats for workers' health are severe, mainly due to uncontrolled and unsafe recycling practices as shown in this picture behind me, where the plastic is burned to obtain the copper in the wires. Then, we had two modules on plastic waste. Besides giving an outline of the challenge, we covered the different plastic waste types. We also looked into recycling technologies and how to produce new products made from recycled plastic waste. And finally, we also looked at management approaches for plastic recycling, for example these plastic waste banks. Then, we covered the issue of construction and demolition waste. Again, we looked at the various types of construction and demolition waste and how they can be managed holistically, starting from production, sourcing, up to the point of demolition, then also looking at recycling and/or disposal. Two common issues for all handling of such special waste fractions, especially when we're interested in their value for recycling, is: The aspect of segregation, so keeping them separate from the other fractions, is the first step in effective recycling. The second aspect regards the issue of controlled processing, to take care to protect worker safety and reduce the risks of pollution or even direct health threats. Thank you for joining and concluding week 4 - and I hope you will join us again for week 5!
