I’m back this week after a horrendous bout with the seasonal flu; made more unfair by the fact that I was actually got vaccinated this year. No time to carry on about that though, on to this weeks write up!
I continue on with m y previous resource with Chapter 9. (Ch.8 was specific to Nairobi) Chapter eight switches to a general overview of the methods by which organic waste is handled in developing nations in Africa and in India. Specifically, the article explores the current state of composting and vermicomposting and whether these methods of removing organic waste from the SWM stream are viable and beneficial. Composting on a small and local level has existed in developing countries for a long time but has recently garnered attention for its potential to reduce Urban Organic Waste on large scale. The potential seems obvious. Organic waste can be taken away from cities, composted, sold in the agricultural sector, reducing the amount of waste in landfills and improving the environment within cities. But apparently the challenges of scaling a composting operation up large enough to deal with the growing amount of waste from urban areas still encounters huge obstacles.
Among them, the rise in contamination from non-biodegradable (plastic, heavy metals, broken glass, other chemicals) that get mixed in with organic waste. As the use of inorganic waste has risen in developing nations so has the difficulty in getting “pure” organic waste for composting and animal feed.
Another problem is motivating households and other generators of organic waste to separate their organic waste from inorganic in order to make it cost effective to handle and process. Because generators more often then not are not the beneficiaries of compost materials, they often don’t see the benefit.
Also, since organic waste naturally implies plant matter, the content (and therefore application) of the waste changes by the season, making it hard to create reliable sources of compost for those that use it the most (namely farmers).
Large composting plants are expensive to build and maintain, making them a much less attractive option to cities. It’s easier and far cheaper to continue open dumping or burning.
That being said, it seems composting has made some inroads within India in certain cities. Some municipalities allow farmers access to dump sites where they auction off portions of the dump. Farmers are permitted to take organic waste away from markets at the end of the day to use as animal feed or fertilizers.
Some private companies have answered the call by setting up services for composting within small areas. One company I read about recently, Mobi Trash operating out of Pune, provides a unique door to door composting service for a fee.
The chapter mentions several private research companies working in the field of composting and vermicomposting.
Vermicomposting, although capable of producing higher quality compost is even more expensive to process then anaerobic compost and so it too, exists most successful on a small scale, although small scale operations have the added benefit of providing employment and visibility to educate the public.
The health hazards of composting are not well documented or understood according to the article and concern mostly those employees in direct contact with the raw materials being composted. One of the primary concerns is that of pathogens that can live within the organic material. Ideally, waste should be composted at 60 C in order to kill pathogens, but due to lack of monitoring and regulations, it’s difficult to know how many composting operations are working within this requirement. Vermicomposting, because it involves live worms, must function at a much lower temperature and statistics on pathogens within these compost materials is not known (as of the date of the article).
The article briefly mentions the sociological issue of ownership. Who owns the compost? For now, composting functions on such a small scale that it’s not an issue that’s received much concern. For now, those entities that perform the function of composting take ownership of it, and from there sell or donate compost to those who use it.
The article draws the conclusion that due to the high cost of composting, it has not become a significant factor in reducing the burden on urban waste management. However, I find this topic worth investigating further. The articles doesn’t give many figures for what the author means by composting being “expensive”. I’d like some more data in that regard.
-Ashley