Dung deal? Korea to turn manure into fuel in push to use less coal.

Could cow dung replace coal? Long used as fuel in countries such as India, dried cattle manure burns well because it contains large amounts of undigested fiber.

Now Korea is accelerating efforts to turn a waste product once used mainly as compost into fuel for power plants. The Ministry of Agriculture, Food and Rural Affairs introduced a plan earlier this year. The government aims to convert 1.18 million tons of livestock manure into solid fuel each year by 2030.

The Agriculture Ministry and the Ministry of Climate, Energy and Environment also launched a 29.8 billion won ($22 million) research project in July to develop technology for producing and using solid fuel made from cow dung.

The government has turned its attention to cow dung due to Korea’s reliance on compost to dispose of livestock manure hitting its limits. More than 50 million tons of livestock manure are produced nationwide each year.

Most livestock manure has traditionally been turned into compost, but shrinking farmland has reduced demand. Excess nitrogen and phosphorus from the compost can also wash into rivers, fuel harmful algae growth and degrade water quality.

Reducing greenhouse gas emissions is another goal of turning cow dung into fuel. One ton of cow-dung solid fuel produces about the same amount of heat as half a ton of bituminous coal.

If Korea meets its target of converting 1.18 million tons of livestock manure into solid fuel each year by 2030, the Agriculture Ministry estimates that annual greenhouse gas emissions could fall by about 500,000 tons. That is roughly equivalent to the annual emissions from 360,000 cars. The fuel could also replace some imported coal with a domestically produced alternative.

The basic process of turning cow dung to fuel is simple. Ferment the moist cow dung, dry them and process them into pellets or powder. About four tons of manure are needed to produce one ton of solid fuel.

The fuel has a heating value of about 3,000 kilocalories per kilogram (1361 kilocalories per pound), roughly half that of conventional coal. Power plants can burn the manure-based fuel on its own or mix it with coal for co-firing.

Korea's efforts to turn cow dung into fuel actually began years ago. Hyundai Steel developed technology to convert livestock manure into solid fuel for use in steelmaking and signed a memorandum of understanding with the Agriculture Ministry in 2021 to expand the use of cow-dung fuel. The company has estimated that using one ton of the fuel can cut carbon dioxide emissions by about 1.5 tons, which could help the carbon-intensive steel industry reduce emissions.

Commercial use, however, has fallen short of expectations. Collecting, drying and processing cow dung is expensive. In addition, maintaining consistent quality and supply is difficult. Producers have also struggled to secure enough buyers for the fuel made from cow dung.

The government has responded by easing production regulations and expanding demand. Regulations revised in July now allow solid fuel to contain at least 50 percent livestock manure and less than 40 percent supplementary materials such as sawdust, rice husks and coffee grounds.

Production capacity and the number of power plants using the fuel are also set to increase.

The government plans to supply about 10,000 tons of solid fuel a year from Suncheon, South Jeolla, and Gimje, North Jeolla. The fuel will be used for commercial power generation at Korea South-East Power’s Yeosu Unit 2 and Korea Southern Power’s Hadong units No. 7 and 8.

The number of generating units using livestock-manure fuel is expected to rise from three this year to eight by 2028.

North Jeolla also plans to invest 198.8 billion won by 2030 in production facilities across Iksan, Jeongeup, Gimje, Wanju County and Buan County. The facilities are expected to process a combined 810 tons of cow dung a day.

The government is now looking beyond cattle manure. The Agriculture Ministry began a demonstration project at the Pocheon livestock cooperative in Gyeonggi to turn pig manure into solid fuel with the help of heat pumps on Sept. 15.

Pig manure contains more moisture than cow dung and has traditionally been more difficult to turn into fuel. The Agriculture Ministry says heat-pump technology could cut the process from several months of composting to just a few hours. The government plans to test the economics of the process and whether power plants can use the fuel through December.

Cost remains the biggest hurdle.

Meeting the current solid-fuel standard of less than 20 percent moisture requires separate drying equipment and significant amounts of energy. Using fossil fuels such as liquefied natural gas to dry cow dung would raise production costs and undermine the greenhouse gas reduction benefits.

The government is therefore developing technology that reuses heat generated when the solid fuel is burned to dry additional manure. The government also plans to develop technology to reduce fine dust, nitrogen oxides and other air pollutants released during combustion.

BY AHN HYO-SEONG [[email protected]]