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Extracting cash from trash

Published:Sunday | November 10, 2019 | 12:00 AMChristopher Serju/Gleaner Writer
Minoru Nakagawa of the Resources and Waste Cycling Bureau explains that, even though they are the same size, the green-labelled bale of compressed aluminium cans weighs 25 kilogrammes compared to the bale of compressed steel cans weighing 60 kilogrammes.

The success of the Tsurumi recycling/incineration centre in Yokohama, Japan, which has kept a tight lid on its solid-waste growth, is due largely to its matching of heavy-duty machinery with an investment in human capital, which makes for a seamless operation.

During a recent guided tour of the plant by participants in the Association for Promotion of International Promotion (APIC) Japan Journalism Fellowship 2019, those present got a first-hand look at what really happens behind its walls.

It begins with the sorting of waste with the machinery known as a bag breaker literally ripping the garbage-filled plastic bags apart, dumping their contents unto the bag breaker conveyor. A worker then removes the pieces of bags by hand as plastic bottles, glass bottles, and cans, among other recyclables, are unloaded on to the separator. All the used bags and other packaging are sent on to the incinerator.

The separator allows heavier bottles to drop through on to another conveyor belt where workers sort them by colour, while the lighter cans and PET bottles continue straight across. From the magnetic separator the steel cans are channelled into the steel press machine, which then crunches and compacts them.

The PET bottles are hand-sorted before going on to a bottle baler which crushes and bales them in the process, while another powerful magnet simultaneously sends the aluminium cans flying across the room, while dirt and debris drop into a container. The cans are collected by the aluminium press machine which compresses them.

But what of the many other types of solid waste?

They are also separated into specific categories before being properly disposed of, including: burnable garbage; non-burnable garbage; spray cans; dry cell batteries; plastic containers and packaging; small metal items; used paper boxes; old cloth and oversized garbage.

This last category includes mattresses, sofas, desks, and chairs, but excludes TVs, refrigerators, washers, dryers, and personal computers. Special arrangement must be made for disposing of these, while small household appliances less than 50 centimetres in size, made mostly of plastic go to burnable garbage. Also qualifying for this category are kitchen scraps from which the excess water has been drained.