Another and some might say, purist video, illustrating the simplicity of the perfect Circular Economy (CE) this one is from EU Environmental department.
The principle is very simple, an old product is the raw materials for the new product, but not necessarily the same product. The steel content from old vehicles has been using this model for decades because steel is expensive, it can be recovered, and processed into new products. Even aircraft, trains are all stripped bare to recover that valuable steel or aluminum to make the next product.
Carpet is another more recent example, with growing sustainability concerns, a famous US carpet manufacturer pointed out its source for “new” raw material is already lying on the floor of your office building, very easy to collect the raw material, process into new carpet saving the enormous cost of shipping and handling virgin raw materials, often created from petroleum.
In Hong Kong, Laputa (http://www.laputa-eco.com) use waste glass bottles to replace sand in locally made paving blocks, after using the paving blocks they can be crushed and recycled for other uses, call it nearly circular. However, the biggest advantage, its local! Shipping heavy paving blocks from EU or elsewhere has a large and an irreversible carbon cost.
At least we have the option, with some other materials, for example, ceramic tiles a common construction material seems irreversible, manufactured close to the source of clay, fired, and shipped all over the world, including into Hong Kong. But unlike nature’s recycling system, there is no local industry queuing to recover and process broken tile, it’s pretty much irreversible, it is difficult and time-consuming to separate from the parent wall, so tends to be mixed with construction waste, and discarded to overflowing landfills.
It will take effort, a drywall manufacturer moves processing adjacent to a power station, the byproduct of air cleaning is your source of raw material is a feasible, bankable proposal. If you have spare gypsum, perhaps a sideline fertilizer business could develop too, gypsum is used for organic farming. But these type of investments demand long-term, almost institutional type planning, that could be difficult, where the prevailing politics may influence decisions.
I can see some hope, and designers are learning, deliberately focusing on paper, aluminum, and steel, valuable materials already flowing through the economy, and perhaps that is the key to Sustainability, like nature, abhor the irreversible economy.