DOI QR코드

DOI QR Code

시멘트 종류별 질산 중화 레드머드 혼입 모르타르의 특성

Characteristics of Mortar Mixed Nitric Acid Neutralized Red Mud by Cement Type

  • Kang, Suk-Pyo (Department of Construction Engineering, Woosuk University) ;
  • Hong, Seong Uk (Department of Construction Engineering, Woosuk University) ;
  • Kim, Sang-Jin (Department of Construction Engineering, Woosuk University) ;
  • Hong, Seok-Woo (Department of Construction Engineering, Woosuk University)
  • 투고 : 2023.08.27
  • 심사 : 2023.10.26
  • 발행 : 2023.12.20

초록

본 연구에서는 산업부산물 레드머드를 건설산업에서의 활용 가능성에 대한 기초 데이터를 분석하기 위해 pH 10~12인 액상 레드머드(LR)를 질산으로 중화하여 pH 7~8인 액상 레드머드를 시멘트 종류에 따른 모르타르에 대체하였다. 평가항목으로 플로우, 응결시간, 압축강도를 측정하였으며 XRD, SEM 분석을 통해 화학적 특성을 분석하였다. 플로우 측정결과 시멘트 종류별 LR과 LN의 경우 Plain과 비교하여 플로우 값이 감소하였다. 응결시간 측정결과 시멘트 종류별 Plain과 비교하여 LR과 LN의 초결시간과 종결시간은 단축되었다. 압축강도 측정결과 액상 레드머드를 슬래그 시멘트에 대체하였을 경우 초기강도가 증가하며 장기강도의 경우 시멘트 종류별 모르타르의 강도 개선이 미미하였다. SEM 분석결과 시멘트 종류에 따른 Plain과 LN에서 공극이 관찰되었고 LR의 미세구조는 섬유상 조직으로 미세구조가 다르게 나타났다. XRD 분석결과 OR과 ON 비교하여 SN에서는 XRD 패턴이 유사하게 나타나고 있지만, 2θ 값 22°에서 피크가 관찰되었다. SR에서는 새로운 피크가 관찰되었다. 따라서 질산 중화 액상 레드머드보다 중화하지 않은 액상 레드머드를 슬래그 시멘트 모르타르에 대체하였을 경우 초기강도가 우수한 것으로 나타났다.

This research explores the potential application of Liquid Red Mud(LRM), a byproduct of industrial processes, in the construction sector. We neutralized LRM(pH 10-12) using nitric acid, aiming to understand its viability in construction applications. The study involved substituting LRM(pH 7-8) in mortar formulations, varying by cement type. We assessed the properties of these mixtures by measuring flow, setting time, and compressive strength. Additionally, X-ray Diffraction(XRD) and Scanning Electron Microscopy(SEM) analyses were conducted to examine the chemical properties. Results indicated a reduction in flow value for LRM and LN(neutralized LRM) compared to the control (Plain ) across different cement types. The setting times(initial and final) for LRM and LN were notably shorter than Plain. In compressive strength tests, LRM replaced with slag cement showed enhanced initial strength, though long-term strength gains were marginal across different cement types. SEM analysis revealed distinct voids in Plain and LN, with LRM exhibiting a fibrous microstructure. XRD patterns in SN(slag neutralized) resembled those in OR(original red mud) and ON(original neutralized), with a notable peak at a 2θ value of 22°. The study concludes that unneutralized LRM, when substituted for slag cement in mortar, yields superior initial strength compared to its neutralized counterpart.

키워드

과제정보

This work is supported by the Korea Agency for Infrastructure Technology Advancement(KAIA) grant funded by the Ministry of Land, Infrastructure and Transport(Grant 22TBIP-C160747-02). This work also was supported by the Technology development Program(S3303468) funded by the Ministry of SMEs and Startups(MSS, Korea).

참고문헌

  1. Lima MS, Thives LP. Evaluation of red mud as filler in brazilian dense graded asphalt mixtures. Construction and Building Materials. 2020 Nov; 260:119894. https://doi.org/10.1016/j.conbuildmat.2020.119894 
  2. Menzie WD, Barry JJ, Bleiwas DI, Bray EL, Goonan TG, Matos G. The global flow of aluminum from 2006 through 2025. VA: U.S. Geological Survey. 2010. 73 p. Report No.: 2010-1256. https://doi.org/10.3133/ofr20101256 
  3. Kang SP, Kang HJ. Strength characteristic and color difference analysis of cement mortar according to the amount of liquefied red mud. Journal of the Korean Recycled Construction Resources Institute. 2018 Jun;6(2):146-52. https://doi.org/10.14190/JRCR.2018.6.2.146 
  4. Liu X, Zhang N, Sun H, Zhang J, Li L. Structural investigation relating to the cementitious activity of bauxite residue-Red mud. Cement and Concrete Research. 2011 Aug;41(8):847-53. https://doi.org/10.1016/j.cemconres.2011.04.004 
  5. Ribeiro DV, Labrincha JA, Morelli MR. Potential use of natural red mud as pozzolan for portland cement. Materials research. 2011 Mar;14(1):60-6. https://doi.org/10.1590/S1516-14392011005000001 
  6. Kang SP, Kang HJ, Lee MH. Characteristics of red mud ceramics according to sintering temperature and contents of red mud from industrial byproducts. Journal of the Korea Institute of Building Construction. 2019 Oct;19(5):401-9. https://doi.org/10.5345/JKIBC.2019.19.5.401 
  7. Liu X, Zhang N, Sun H, Zhang J, Li L. Structural investigation relating to the cementitious activity of bauxite residue-Red mud. Cement and Concrete Research. 2011 Aug;41(8):847-53. https://doi.org/10.1016/j.cemconres.2011.04.004 
  8. Kang SP, Kang HJ. Strength characteristic and color difference analysis of cement mortar according to the amount of liquefied red mud. Journal of the Korean Recycled Construction Resources Institute. 2018 Jun;6(2):146-52. https://doi.org/10.14190/JRCR.2018.6.2.146 
  9. Kang SP, Kang HJ. Effects of red mud and Alkali-Activated Slag Cement on efflorescence in cement mortar. Construction and Building Materials. 2017 Feb;133:459-67. https://doi.org/10.1016/j.conbuildmat.2016.12.123 
  10. Wang J, Zelong M, Ting Z, Wang D. Durability degradation of tunnel-lining-shotcrete exposed to nitric acid:Neutralization and nitrate ion migration. Construction and Building Materials. 2022 Jun;336:127554. https://doi.org/10.1016/j.conbuildmat.2022.127554 
  11. Choe G, Kang S, Kang H. Characterization of slag cement mortar containing nonthermally treated dried red mud. Applied Sciences. 2019 Jun;9(12):2510. https://doi.org/10.3390/app9122510 
  12. Ribeiro DV, Labrincha JA, Morelli MR. Potential use of natural red mud as pozzolan for portland cement. Materials research. 2011 Mar;14(1):60-6. https://doi.org/10.1590/S1516-14392011005000001 
  13. Park CJ, Park JH, Seo SK. Basic characteristics of slag cement using co2 fixed desulfurized gypsum. Journal of the Korean Recycled Construction Resources Institute. 2023 Mar;11(1):25-31. https://doi.org/10.14190/JRCR.2023.11.1.25 
  14. Kunther W, Lothenbach B, Scrivener K. Influence of bicarbonate ions on the deterioration of mortar bars in sulfate solutions. Cement and Concrete Research. 2013 Feb;44:77-86. https://doi.org/10.1016/j.cemconres.2012.10.016 
  15. Ortega J, Cabeza M., Tenza-Abril AJ, Real T, Climent MA, Sanchez I. Effects of red mud addition in the microstructure, durability and mechanical performance of cement mortars. Applied Sciences. 2019 Mar;9(5):984. https://doi.org/10.3390/app9050984 
  16. Niu M, Li G, Zhang J, Cao L. Preparation of alkali-free liquid accelerator based on aluminum sulfate and its accelerating mechanism on the hydration of cement pastes. Construction and Building Materials. 2020 Aug;253:119246. https://doi.org/10.1016/j.conbuildmat.2020.119246 
  17. Yan P, Chen B, Aminul HM, Liu T. Influence of red mud on the engineering and microstructural properties of sustainable ultra-high performance concrete. Construction and Building Materials. 2023 Sep;396:132404. https://doi.org/10.1016/j.conbuildmat.2023.132404 
  18. Ortega JM, Cabeza M, Tenza-Abril AJ, Real-Herraiz T, Climent MA, Sanchez I. Effects of red mud addition in the microstructure, durability and mechanical performance of cement mortars. Applid sciences. 2019 Mar;9(5):984. https://doi.org/10.3390/app9050984 
  19. Nebel H. Continuous preparation of calcite, aragonite and vaterite, and of magnesiumꠓsubstituted amorphous calcium carbonate (Mg-ACC). Journal of Inorganic and General Chemistry. 2008 May;634(8):1439-43. https://doi.org/10.1002/zaac.200800134 
  20. Garanayak L. Strength effect of alkali activated red mud slag cement in ambient condition. Materials Today: Proceedings. 2021 Jun;44(1):1437-43. https://doi.org/10.1016/j.matpr.2020.11.630 
  21. Van ND, Imasawa K, Hama Y. Influence of hydrothermal synthesis conditions and carbonation on physical properties of xonotlite-based lightweight material. Construction and Building Materials. 2022 Feb;321:126328. https://doi.org/10.1016/j.conbuildmat.2022.126328 
  22. Wu Z, Li L. Gao F, Zhang G, Cai J, Cheng X. Resource utilization of red mud from the solid waste of aluminum industry used in geothermal wells. Materials. 2022 Nov;15(23):8446. https://doi.org/10.3390/ma15238446