From kitchen sink to animal farm: Life cycle of food waste in Seoul

The Korea Times

The Korea Times

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Sat, September 30, 2023 | 05:24

Society

From kitchen sink to animal farm: Life cycle of food waste in Seoul

Posted : 2020-08-19 17:31

Updated : 2020-08-20 19:30

An employee of Dobong Food Disposal Processing Plant manually removes plastic, bones and seeds from the food waste which has just arrived on a conveyor belt. /Korea Times photo by Kim Se-jeong

By Kim Se-jeong

The almost ten million residents of Seoul produce roughly 2,100 tons of home food waste every day.

More recently in Seoul's large residential apartment complexes, residents dispose of food waste in modern communal electronic bins that measure how much food waste each apartment disposes of and charges a monthly waste management fee accordingly, while residents of other types of housing load their food waste into dedicated plastic bags or containers before leaving them outside for collection.

A visit to Dobong Food Disposal Processing Plant located in Dobong District, northeastern Seoul, shows what happens next.

As the waste arrives at the center in collection trucks, non-recyclable food waste items, for example chicken bones and peach seeds, are removed by hand and machine. The usable waste is then crushed into a puree and spin- and air-dried to create a powder.

This stage of the process generates a large amount of liquid waste which is transported to another location for separate disposal processing.

In the final stage, the powder is mixed with wheat husks and chemical additives to make animal feed. The mixture is loaded into huge bags for 20 local poultry and pig farmers to pick up ― although the latter are temporarily not receiving feed because of an African swine fever outbreak. To make sure the feed is appropriate for animal consumption, samples are sent to a local university every six months for testing.

While the Dobong plant turns the waste into animal feed, other processing plants process waste to create fertilizer.

The Dobong plant processes an average of 70 to 80 tons of food waste a day and produces between eight and nine tons of animal feed. The entire process takes nearly half a day and the machines are in operation from Monday through Saturday.

Choi Jong-seon from the plant said Korean food generates a big volume of liquid waste and that non-food waste makes his team's job more difficult.

"People discard meat bones or big fruit seeds together with other food waste, but we can't process these at the center, Choi said, adding dried fruit and vegetable skins, shells and tea bags aren't food waste either. "If residents would separate them from food waste, it would make our job much easier."

Opened in 2001, the Dobong plant is one of three plants in the capital that is funded by local taxpayers, the other two are located in Dongdaemun and Songpa districts.

Other districts pay private companies to do the job. The companies transport the food waste to their own processing plants that are mostly located in Gyeonggi and Chungcheong provinces.

Choi said the biggest advantage of having its own food waste process plant in the district is that it can provide a timely service without any delays.

"In 2013, Seoul had a food waste crisis, as private companies refused to collect it. We didn't have to worry about that," Choi said.

An ocean dumping ban that went into effect in 2013 raised spending for private companies which had previously dumped liquid waste into the sea.

It could be every district government's wish to have their own food waste processing plants to ensure continued public service and to avoid hassles with private companies, but this is easier said than done.

"Finding a place to build one now would be extremely difficult because there's no empty land and also residents don't want the plant in their neighborhoods," an official from Mapo District said. Mapo also pays private companies to process waste.

Seodaemun District is currently pushing to have its own plant in Gyeonggi Province, but the plan is on hold due to opposition from local residents.

Together with processing, the district and the Seoul city governments are also pushing residents to reduce the amount of food waste, which would be a long-term and sustainable solution to related issues.

Local governments are promoting the earlier mentioned food waste collection bin machines. As they are equipped with radio-frequency identification (RFID) technology, the devices can show users the entire amount of waste across the city. While these machines are currently only found in apartment complexes, the city government said it has proven effective in encouraging people to reduce the amount of waste they generate.

The city has installed 15,100 of these collection machines across Seoul, and is planning to increase the number.

"We can't stop producing food waste, but we can reduce the amount. This is important and that's why local and city governments are trying to encourage residents to do so," a Seoul city government official said on condition of anonymity.

skim@koreatimes.co.kr