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Waste not, want not

Trash sorting is not an end in itself but rather a means to more effective waste recycling and treatment
 
A known but poorly understood concept - garbage classification - recently captured public attention in China as some cities have begun to strictly implement their sorting regimes for household waste. According to a plan issued by the Ministry of Housing and Urban-Rural Development, all 46 major cities in China should have their trash sorting systems in place by 2020; and all cities at or above the prefecture level should have done so by 2025.
 
The amount of garbage produced has been on a rapid rise. According to statistics, urban garbage clearance in China is 215 million metric tons per year, 56 percent of which goes into landfills, with only about 40 percent incinerated, recycled or reused.
 
Landfill uses up large amounts of land resources and poses potential risks to the nearby environment. Therefore, we must find appropriate ways to sort, recycle and reutilize trash.
 
From a resource reutilization perspective, trash is nothing but a misplaced resource. The composition of residential waste differs, depending on lifestyles and geographical conditions. But based on the results of a survey conducted in cities including Beijing, Shanghai and Xi'an, kitchen waste makes up 40 to 60 percent of residential trash, while recyclables such as paper makes up 20 to 40 percent. Due to different dietary habits, the calorific values of kitchen waste in China is higher than the World Bank's recommended value, making it fit for waste-to-energy applications for power generation.
 
The amount of waste that is recyclable is also increasing as a result of the ballooning packaging produced by the expanding express delivery sector. With proper treatment, most of this can be recycled or reutilized.
 
Since 2000, pilot projects in garbage classification have been put in place in cities such as Beijing, Shanghai and Xiamen, and other cities have also followed successively. But even though trash sorting has been done for over 20 years, the results leave much to be desired. This is because the implementation of the sorting regime encounters many problems and challenges.
 
For instance, garbage classification calls for the participation of many stakeholders. And as residents produce most of the household trash, they are considered to be mainly responsible for trash sorting.
 
But there are many steps involved in trash sorting, treatment and recycling, and some sorting is best done in a centralized manner in the later stages of the cycle. Also, garbage classification should be done at different stages in the cycle depending on the economics of different types of trash.
 
Incomplete or inadequate supporting infrastructure for trash reutilization makes it hard to create value out of garbage classification and may even defeat the purpose. Also, many cities have yet to put in place a trash treatment system to make garbage classification work as their urbanization process is incomplete. As a result, these cities are incapable of sorting and treating waste.
 
In some areas, residents sort their trash and deliver it separately, only to see it mixed up at transfer stations or in later stages of the process. Mishandling of this type often discourages residents from continuing to sort their garbage.
 
The diversity of residents also makes it harder to coordinate trash sorting. And even though it is beneficial for the urban environment if residents sort their own trash, not everyone is willing to undertake the effort. So while it is possible to use monitoring and punitive measures to improve compliance, it will entail significant costs.
 
A more effective method is to help residents develop the habit of trash sorting through awareness of the benefits, and to punish noncompliance so that residents will eventually want to do it spontaneously.
 
Additionally, heterogeneous standards across different regions make it difficult to scale up trash sorting and can constrain the development of downstream industries. So, uniform standards need to be formulated in the early stages of scaling up trash sorting in order to enable the practice on a national scale.
 
Forceful administrative measures are needed in the initial stages of running a trash sorting campaign to reverse deep-rooted habits. How strictly trash sorting is enforced must also be compatible with downstream trash reutilization capacity. And while it is a good idea to take a comprehensive view of the different steps involved in trash sorting, recycling and treatment and focus on the sorting of hazardous waste and recyclables in particular, it is also necessary to ramp up the trash treatment capacity to pave the way for large-scale implementation of trash sorting.
 
A multistage approach to trash sorting is necessary. So while residents can take care of the initial sorting, trash should be further classified in the later stages of the cycle, residents should not be burdened with the full responsibility of sorting; and they need to be informed of the purpose of this requirement. For that we need to build a comprehensive industry chain for trash recycling and reutilization as fast as we can.
 
Strict implementation of trash sorting only makes sense when there is a well-functioning downstream market for it. And it also needs to be said that trash sorting has to make economic sense for the practice to be sustainable. Otherwise sorting becomes untenable if it is done just for the sake of sorting.
 
A multitude of approaches should be considered, including financial. For example, it may be a good idea to charge a trash collection service based on the amount, which could be an incentive for residents to minimize their trash.
 
Trash sorting is an imperative. There is a plethora of best practices and lessons from other countries that we can learn from. And in light of these experiences and the situation at home, we can develop reasonable and effective measures with full consideration that trash sorting is not an end in itself, but rather a means to more effective trash recycling and treatment.
 
The author is director of the China Institute for Studies in Energy Policy at Xiamen University. The author contributed this article to China Watch, a think tank powered by China Daily. The views do not necessarily reflect those of China Daily.
 
(China Daily Global 07/24/2019 page13)

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