TheJakartaPost
Please Update your browser
Your browser is out of date, and may not be compatible with our website. A list of the most popular web browsers can be found below.
Just click on the icons to get to the download page.
Shinagawa high-tech bonfire transforming garbage to light
Hot job: Hidenori Yokoyama (left) gives an explanation on the Shinagawa incineration plant in Tokyo
Change Size
Hot job: Hidenori Yokoyama (left) gives an explanation on the Shinagawa incineration plant in Tokyo.(JP/Musthofid)
Jakarta and Tokyo are almost the same in terms of population density. However, while the former is left scratching its head over the garbage problem, the latter sees light as the end product of high-tech waste management.
Thousands of tons of trash are collected from household and business activities, but in the end only one-twentieth of the volume ends up at landfills.
The rest either goes up in smoke or becomes byproduct in the form of building material, heat and electricity, thanks to incineration processes in incineration and pulverization plants in 23 wards under the Clean Authority of Tokyo (CAT).
CAT is a special-purpose municipal body established by the consensus of the 23 wards, based on the Local Autonomy Act, in order to deal with waste management, which had a budget of nearly US$700 million last year.
The 23 wards are responsible for waste collection and recovery of resources, while the Tokyo metropolitan government manages the final disposal at landfills.
The exhaust gas treatment facility ensures that the smoke emitted from the stacks is not hazardous.
A gas cooler prevents the resynthesis of dioxins by rapidly cooling the high-temperature exhaust gas to about 150 degree Celsius.
The bag filter, with the help of special auxiliary agents and calcium hydroxide sprayed into the exhaust gas, removes dioxins, sulfur oxide, hydrogen chlorides and particulates.
Gas scrubbing also removes hydrogen chloride, sulfur oxide and mercury, while the catalyst reaction tower decomposes any dioxins and nitrogen oxide present in the exhaust gas through catalytic action.
The Shinagawa incineration plant handles 300 trucks of garbage every day. “Last year we had 15 million tons of garbage,” plant manager Hidenori Yokoyama said.
When the garbage trucks are full, they roll to the incineration site. Equipped with two incinerators, the plant handles burnable trash from Shinagawa ward, with a daily capacity of 600 tons per day. That’s about the amount of waste produced by 600,000 people per day.
To track trash inflows, garbage trucks are weighed upon arriving arriving at the plant. They dump their hauls from a platform into the refuse bunker, which measures 70 meters long, 12 m wide and 20 m deep.
Two large cranes, each weighing 3 tons, hang from the gantries, operating automatically. The claws stir the pile of trash three times to make burning easier, before grabbing car-sized clumps and transferring them to the furnaces.
The entire operation is monitored around the clock from a central control room with live video feeds of the furnaces, bunker and other parts of the plant.
All this burning produces byproducts. One is huge volumes of exhaust gas. This has to go through an extensive treatment process to reduce the environmental impact of toxins such as mercury and dioxins. By burning the waste at more than 850 degree C, the formation of dioxins can be kept in check.
The plant generates 10 megawatts (MW) of electricity. Half the amount is for its own consumption and the other half connects to the grid to be distributed to 10,000 households nearby. Another product of incineration is bottom ash, which is used as a substitute for clay in the production of cement.
Among the 23 plants, the Shinkoto site has the largest incineration capacity, with 1,800 tons garbage per day and a power-output capacity of 5 MW.
