Zhu Dajian, Professor & Doctoral Supervisor, Tongji SEM

On March 5, 2019, the 131^st Wenhui Lecture Halls launched the online lectures for the first time. Zhu Dajian, Director of the Institute of Sustainable Development & Management of Tongji University, gave a speech through mobile voice broadcasting on the topic of “Garbage Revolution: Tokyo Experience and Shanghai Strategy”. He elaborated his opinions from three aspects:

First, compared with Tokyo, What is the status of garbage classification and disposal in Shanghai?

Second, how did Tokyo implement the garbage revolution, and what experience can be used for reference by Shanghai;

Third, for the higher goal of the garbage revolution is to build a circular economy society, Shanghai needs to set longer-term goals.

Multiple similarities determines that Tokyo is the target object

Shanghai and Tokyo have three links in terms of garbage disposal. First, both cities are in East Asian countries with more people and less land, so they cannot use large-scale landfill to deal with garbage. Incineration of refuse is the only way.

Second, these two cities have similar living habits and consumption structures. Third, Tokyo’s demographic structure and urban spatial structure are similar to those in Shanghai.

Comparison of waste production between Shanghai and Tokyo

In 2018, Shanghai’s per capita daily garbage output is about 1.1 kilograms, and this peak continues to climb. In 1989, the per capita daily garbage output in Tokyo reached 1.6 kilograms. At that time, the per capita GDP was about 20,000 US dollars, which was equivalent to that of Shanghai in 2018. Since then, with the mandatory garbage revolution, the per capita waste discharge has gradually decreased. This numerical value has been reduced to 0.8 kg at present.

Two gaps between Shanghai and Tokyo

As we can see from the current situation of domestic garbage disposal in China between 2006 and 2014, on the one hand, the total garbage production and per capita garbage output continue to increase; on the other hand, the garbage disposal structure is mainly landfill, supplemented by incineration. This situation reflects the basic status quo of Shanghai, and also the two gaps between Shanghai’s household waste disposal and Tokyo’s.

In 2018, Shanghai’s domestic waste incineration treatment accounted for 40%, and landfill accounted for 40%. In contrast, in 2015, the proportion of domestic waste incineration in Tokyo was as high as 75%, and landfill treatment accounted for 3%. This data has been relatively stable. However, Tokyo uses incineration as an intermediate treatment method for domestic garbage, and landfill as a terminal treatment method, which is for burying the ash after burning. Therefore, one of the gaps between Shanghai and Tokyo is that waste disposal has not yet been transformed into an incineration dominated model with landfill being the terminal treatment. This model is suitable for super-large cities in East Asia with a large population and relatively little land.

The key milestones of the Tokyo garbage revolution

The first stage (1960-1970s): dominated by landfill, triggering “Tokyo Garbage War”

All the garbage in Tokyo was sent to the Gulf area such as Jiangdong District for landfill. There were many kitchen wastes in these unclassified garbage, which led to serious air pollution and hygienic problems. People began to resist and eventually caused the famous “Tokyo Garbage War”.

The second stage (1980s): incineration of combustible waste, mainly landfill of non-combustible

The year of 1980 is the starting of Tokyo from mixed garbage to garbage sorting. At that time, the garbage was simply divided into combustible garbage and non-combustible garbage, in which combustible waste was incinerated and non-combustible garbage was mainly treated with landfill. However, when the amount of landfill is greatly reduced and incineration becomes dominant, landfill becomes the terminal disposal method for treating fly ash after incineration.

The third stage (after 1990): sorting large pieces of garbage to increase resource utilization

1990 was a very important milestone in the garbage revolution of the 23districts in Tokyo. Tokyo began to further distinguish between resource waste and bulky waste, which also led to an increase in recycling.

Shanghai has three major late-move advantages

From the perspective of the object, Shanghai has the “comprehensive” advantage. The garbage sorting in Tokyo has been implemented step by step. In Shanghai, from the very beginning, the waste is divided into four main categories: “hazardous garbage, recyclables, wet garbage, and dry garbage”, apt for comprehensive promotion of integrated treatment encompassing recycling, incineration, landfill, etc.

From the perspective of process, it has the advantage of “retroaction”. The traditional way of dealing with garbage mainly relies on the back-end processing without solving the front-end problem of garbage generation. However, the current approach is to decrement and categorize from the source by framing the capacity without expansion and forcing inversely the classification and resource utilization at the front-end.

From the perceptive of subject, it has the advantage of backwardness driven by “governance”. Waste management requires mobilization and participation of the government, corporate and all sectors of society. Such a governance structure can transform the waste classification from departmental action into a chorus of the whole society, helping to speed up the garbage revolution.

The strategic goal of the Shanghai’s garbage revolution

Since 2000, after achieving the first step of categorization, incineration dominant garbage treatment, and source reduction, Tokyo began the second step of the garbage revolution—building a recycling society, that is, “zero waste city”.

The concept of “zero waste city” requires that the urban material flow is a closed-loop and there is so little waste discharge as possible, aiming at minimizing the disposal methods such as landfill and incineration. The ultimate goal of Shanghai is to live up to such standards.

Improve resource productivity and recycling rates, and reduce disposal amount

Japan’s circular society development plan proposes three goals in accordance with the outlet, the intermediate and the entrance of the material flow. The first is to reduce the amount of disposal, which means, largely decrease the disposal rate at the terminal treatment stage. Secondly, to improve the circulation rate. To be specific, ensure the resource recycling rate is increased by 80% compared with 1990. Third, to increase the resource productivity rate, that is, greatly accelerate the GDP output of per unit consumption of resource.

In virtue of a circular economy to a low-waste, even waste-free city

In summary, the garbage revolution mainly includes two stages and two kinds of thinking. Viewing the garbage problem from the whole process of material flow, it can be divided into four states: the ideal state is items sharing, replacing possession with sharing. The second state is the reuse of items. The third state is to transform items into resource. The fourth state is harmless disposal, including incineration and landfill. During the first phase of garbage revolution, the key point is to solve the waste discharge by harmless disposal and reduce the quantity through recycling. The second phase of the revolution is the advanced stage of items sharing. Using less material resources to create more economic and social utilization, to build a city with low waste and even no waste.

Therefore, the garbage revolution in Shanghai faces two major tasks. First, solve the current problem of garbage classification and peak emissions. Second, move towards a recycling society with low waste and no waste. Incineration and landfill are only transitional methods. The key point depends on whether the city can eliminate waste from the source and the process of production and consumption.