Sustainable CO2 utilization and calcium carbonate recovery from calcium carbide wastewater
Kamchai Nuithitikul,
Peerapong Jitsangiam,
Pumipat K. Pachana,
Methawadee Arbwaree,
Ubolluk Rattanasak,
Vanchai Sata,
Prinya Chindaprasirt
Affiliations
Kamchai Nuithitikul
Biomass and Oil Palm Center of Excellence, School of Engineering and Technology, Walailak University, Nakhon Si Thammarat 80160, Thailand
Peerapong Jitsangiam
Center of Excellence in Natural Disaster Management, Department of Civil Engineering, Faculty of Engineering, Chiang Mai University, Chiang Mai 50200, Thailand; Multidisciplinary Research Institute, Chiang Mai University, Chiang Mai 50200, Thailand
Pumipat K. Pachana
Center of Excellence on Environmental Health and Toxicology (EHT), OPS, MHESI, Bangkok 10400, Thailand; Department of Chemistry, Faculty of Science, Burapha University, Chonburi 20131, Thailand
Methawadee Arbwaree
Department of Chemistry, Faculty of Science, Burapha University, Chonburi 20131, Thailand
Ubolluk Rattanasak
Department of Chemistry, Faculty of Science, Burapha University, Chonburi 20131, Thailand; Corresponding author
Vanchai Sata
Sustainable Infrastructure Research and Development Center, Department of Civil Engineering, Faculty of Engineering, Khon Kaen University, Khon Kaen 40002, Thailand
Prinya Chindaprasirt
Sustainable Infrastructure Research and Development Center, Department of Civil Engineering, Faculty of Engineering, Khon Kaen University, Khon Kaen 40002, Thailand; Academy of Science, Royal Society of Thailand, Dusit, Bangkok 10300, Thailand
Summary: The hydration of calcium carbide for acetylene production generates calcium carbide residue (CCR), primarily as a calcium hydroxide slurry, often disposed of in ponds, increasing soil alkalinity and CCR wastewater. This study, thus, explores converting CCR wastewater into calcium carbonate (CaCO3) via CO2 carbonation with triethanolamine (TEA). After initial carbonation and filtration, the carbonated CCR solutions were heated to 80°C to remove CO2 and the solution underwent three cycles of dissolution and carbonation, promoting resource sustainability. TEA enhanced cubic calcite formation, but only non-TEA solutions successfully precipitated CaCO3 upon reuse. Successive recycling rounds reduced CCR dissolution and CaCO3 formation due to impurity buildup. Maximum CaCO3 yields were 23.0% for heated solution and 36.6% for non-heated solution. To enhance process sustainability, dilution with raw water is recommended to counter impurity accumulation and optimize recycling conditions.
