KEEP ‘EM SEPARATED: Introducing Household Waste Separation Efforts in Chinese Cities
What can China learn from the 1990s American band Offspring? If you consider the lyrics of their hit song “Come Out and Play,” potentially a lot. NEEDigest introduces a new series looking at household waste separation efforts in Chinese cities, to help readers see exactly why, when it comes to garbage items, “ya gotta keep ‘em separated.”
Between 2001 and 2006, incineration went from being practically non-existent in China to a popular method for municipal solid waste (MSW) treatment. Deemed an appropriate option for cities with higher GDPs and land scarcity constraints – primarily ones clustered along the coast – the Central government set a target, under the 11th Five Year Plan for incineration to be used to treat 30% of China’s managed MSW by 2030.
Since 2006, Chinese cities have discovered that treating waste by incineration is not as simple as supposed. For waste to burn efficiently, and co-generate electricity, it should be relatively dry. Chinese MSW is very wet, owing to its high percentage of kitchen waste and the diversion of recyclable content by informal collectors, meaning it does not combust easily. To combat this problem, MSW must either be pre-treated to remove moisture (a costly and time-consuming process) or auxiliary fuel, like coal, must be added as feedstock (a costly and environmentally unfriendly option).
Another alternative is to change the composition of the waste stream itself so that it is more appropriate for incineration. This can be achieved by separating the MSW into combustible and non-combustible components. Separating waste after it has been collected is both expensive and requires significant space. Household separation, by comparison, is much more cost-effective, though difficult to implement. Recalling the space constraints that originally prompted Chinese cities to turn to incineration, it is easy to see why household separation programs are popping up in Chinese cities utilizing incineration technologies.
In addition, cities are beginning to realize the value of China’s organic waste stream. If separated, transported and treated correctly, it makes a market viable and environmentally beneficial compost product. Efficient sorting is a critical pre-requisite for composting MSW. As such, both in cities where incineration alone is replacing landfills and those where incineration and composting together are becoming the preferred alternative to landfilling, household separation plays a key role.
The next series, “Keep ‘em separated,” will look at the different household waste separation campaigns underway in Chinese cities, in order to assess the current status and future prospects of these critical efforts.