This prediction seems a bit alarmist since governments in high-income countries have effective programs to recycle waste or dispose of it in environmentally safe ways. Low-and middle-income countries are creating more and more of such programs as their economies and government revenues grow. In addition, it is likely that new, efficient and low-cost techniques for the disposal of wastes will be developed in the future.
Existing recycling efforts are very effective in high-income countries where households create most of solid waste, sort it into four main types, even though many consider this system to beonce the cost incurred by household in sorting, the cost of extra trucking separate types of waste and the imperfect sorting by households are .
Food and other organics make up 44 percent by weight of the. Some of this waste is used to feed animals and produce compost for agriculture, but most goes into landfills. The biggest problem facing the disposal of this type of waste is the growing scarcity of landfill sites, which is caused by public opposition based on concerns about the environment and by the rising cost of government regulations.
The second-largest type of household waste at 17 percent is paper and cardboard. Most of it is turned profitably into recycled products, just as it has been before the government recycling programs were created. Crushed glass (5%) is used to improve the quality of concrete and asphalt on roads. Metals (4%), especially aluminum, are absorbed in the production of new metals. Wood (2%) can be burned. Rubber (2%) and “other” substances (14%) also are burned or go to landfills.
The third largest category of waste at 12 percent is plastics, which receives the largest amount of public attention – the media regularly display pictures of sites on land and of waterways filled with plastics and of animals suffering from entanglement with containers and nets and even drinking straws. Much media attention was recently given to the plastics covering large areas of open oceans and the threat to marine life caused by their break-down into micro-particles.
One reason for this public and government attention to plastics is that their disposal is very difficult and costly. Thus, because of the particular molecular structure of some types of plastics, in 2016 only eight percent of the annual 32 million tons of it in the United States was recycled and turned into new commercial products. The remaining 90 percent was incinerated, creating commercially valuable energy but also polluting the air, was buried in landfills where it can take up to 10,000 years to decompose or simply remained uncollected creating health hazards for humans and endangering wildlife on land and in the oceans. This problem is especially serious in low- and middle-income countries of the world where most plastic waste is uncollected. Plastics are also the target of many regulations to reduce their use by consumers such as the contentious ban on plastic shopping bags and drinking straws.
The good news is that a new technology has been developed for the productive re-use of plastic waste. Information about it can be found at the company website, which claims that it “Turns plastic trash into profit by taking any type of unsorted and unwashed plastic waste into an advanced building material”. (Disclaimer: I have no relationship with this company).
The new technology shreds unwashed and unsorted plastic products, super-heats these shreds with water until they are ready to be compressed into blocks that remain solid without the use of adhesives or other chemicals. These blocks are extremely durable, offer very good insulation from temperature and sound and do not emit harmful fumes. They can be used in many types of construction but are likely to be particularly useful in building low-cost homes in developing countries. Holes can be drilled into the blocks to allow the insertion of stabilizing rods, pipes and wires. For appearance and comfort, they can readily be covered with drywall, wood or stucco.
The machines needed to convert plastic trash into useful bricks are simple in design and can be operated by few, mostly low-skilled workers. They fit onto flat-bed trucks and can be driven to location where plastic waste has accumulated.
The machinery used to produce the bricks can be purchased and operated by government agencies or by private entrepreneurs, who can obtain the plastic inputs they need from municipal collection stations at low or zero cost, possibly even being paid for doing a job the stations no longer need to do. These operators can sell the plastic bricks at prices competitive with those made from clay or concrete.
The biggest potential benefits of producing plastic bricks from waste is in low- and middle-income countries where almost all plastic waste ends up in open dumps. The owners of the machines can buy the plastics from scavengers now working these dumps or who collect it from the environment. There is a growing market for low-priced bricks for construction of simple, low-cost homes in these countries.
Governmental aid-giving or private non-profit organizations might consider subsidizing the owners of the machines turning waste into useful products, reduce environmental pollution, encourage economic development and prevent the world from “living in waste.”
Emeritus Professor of Economics, Simon Fraser University
Senior Fellow, The Fraser Institute