::: Monthly News

Farewell to Fly Ash Burial Taoyuan Toward A Zero-Waste City Ahead of Other Counties and Cities

In view of the immature waste-to-resource technology, Taiwan used to treat fly ash from incinerators by stabilization and solidification before dumping in landfills, causing a severe insufficiency of landfill capacity. As Taoyuan outputs fly ash at about 12,000 MT a year. To recycle fly ash for reuse, the Taoyuan Department of Environmental Protection (TYDEP) announced the results of qualified recycling service provider selection at the end of the year. A total of 3 qualified fly ash recycling service providers were selected to recycle all fly ash in the city for multiple reuses ahead of other counties and cities in Taiwan. The project is expected to start next June. From then on, no more fly ash will be dumped in landfills, and landfills considered as a nimby facility will walk into history in Taoyuan.

According to the TYDEP, incinerator fly ash has always been a big problem in waste disposal across Taiwan. In general, fly ash intended for dumping in sanitary landfills after stabilization and solidification should be dumped in an individual landfill site. As the landfill capacity reduces, the landfill disposal fee of fly ash has increased from NT$6,000/MT in the past to over NT$16,000/MT in 2019. To hit the nail on the head of the problem, the TYDEP began to evaluate the technical feasibility of recycling fly ash through waste-to-resource in 2019. Besides encouraging the improvement of fly ash washing technology, the TYDEP also promoted the development of recycling washed fly ash through waste-to-resource for reuse. By that time, the TYDEP will share this experience with other counties and cities in order to resolve the incinerator fly ash problem across Taiwan.

According to TYDEP Director-General Dr. Li-Teh Lu, washing to reduce the chloride in fly ash is the prerequisite for recycling fly ash. After one year of testing, Hsin Yung Incineration Plant in Taoyuan reduces chloride in fly ash from 20% in the past to 3% with the low-water-consumption washing technology and equipment. Currently, it is actively building a washing plant for commercial operation in May 2021. Washed fly ash will be recycled for reuse with different treatment technologies by the three qualified service providers. As fly ash contains high calcium oxide, and it has been proven that calcium oxide can replace part of the materials used in cement kilning or metal smelting, and stabilized bottom ash will produce after high-temperature smelting, the product can be used as construction materials. Currently, incinerator bottom ash in Taoyuan has been recycled to produce recycled aggregate used in all infrastructure projects in Taoyuan City with eminent results. Taoyuan City is also awarded the 2020 National Civil Servant Contribution Award (Group) for recusing recycled aggregate.

According to related regulations, the three qualified fly ash recycling service providers selected at the end of 2020 will submit a fly ash recycling proposal to the TYDEP. After the proposal is approved, they will implement fly ash recycling. In the future, after recycling all fly ash, the incinerator bottom ash and fly ash from Taoyuan will all be recycled and reused to thoroughly resolve the fly ash problem and eliminate the need to find new sites for new landfills.

 

Farewell to Fly Ash Burial Taoyuan Toward A Zero-Waste City Ahead of Other Counties and Cities

 

Farewell to Fly Ash Burial Taoyuan Toward A Zero-Waste City Ahead of Other Counties and Cities

   

Farewell to Fly Ash Burial Taoyuan Toward A Zero-Waste City Ahead of Other Counties and Cities