I'm not sure how reliable this source is, but apparently there was some kind of political embarrassment in China following a 2016 documentary:
a 2016 documentary
called “PLASTIC CHINA” garnered
much attention and caused deep
embarrassment to the Chinese
government yet again. The film
depicted the lives of two families who
make a living recycling imported
plastic waste. Ultimately, this film
may have been the straw that broke
the proverbial camel’s back—leading
China President Xi Jinping to push
for the current ban and emphasizing
phrases like “Chinese dream” and
“beautiful China” along with a desire
for environmental improvement.
Apparently in the aftermath China closed down quite a few of the smaller recycling plants.
What exactly are “National
Sword” and “Blue Sky 2018”?
“National Sword” was an initiative that
took place in 2017, which inspected
Chinese recyclables processing
facilities and shuttered many of the
smaller ones.
We are now in the midst of “Blue Sky
2018,” scheduled to run March through
December of 2018. China’s customs
authority, the General Administration
of Customs of the People’s Republic of
China, has announced this period of
special actions against foreign garbage
smuggling. [...]
Though it’s impossible to know
exactly what China is thinking, it is
assumed that some of its ultimate goals
with these programs are:
- A consolidation of recycling
facilities into “Eco-Parks”
- Larger, cleaner, better-regulated
facilities
- To bolster its own domestic
markets
It notes a bit later on that plastics were not the only target of these wave of regulations. Various kinds of scrap metal, presumably also hard to recycle cleanly due to contaminants, e.g. compressed cars (scrap), were also banned.
There does seem to be precedent for Chinese authorities being quite sensitive to media reporting about pollution from their recycling industry.
In 2010, Adam Minter, Bloomberg's Shanghai correspondent, visited Wen'an - then the heart of the global scrap plastic trade – undercover. In 2011 the Chinese government introduced new regulations and shut down the scrap plastic trade in this part of the country.
It's also not the first time China has tightened its import standards.
last time the Chinese tightened standards, in 2013, the city [of Edmonton] saw a $1-million drop in revenue from the flooded market. Officials hope careful management and attention to detail this time will mitigate the impact.
And since China sent a notice to the WTO before the last tightening of standards, here's the official motivation from it:
“We found that large amounts of dirty wastes or even hazardous wastes are mixed in the solid waste that can be used as raw materials. This polluted China’s environment seriously,” China’s WTO filing said.
“To protect China’s environmental interests and people’s health, we urgently adjust the imported solid wastes list, and forbid the import of solid wastes that are highly polluted.”
As some of the news stories mentioned, some countries objected, but China was unmoved.
