Immobilization and leaching characteristics of fluoride from phosphogypsum-based cemented paste backfill

Abstract

Phosphogypsum (PG) is a typical by-product of phosphoric acid and phosphate fertilizers during acid digestion. The application of cemented paste backfill (CPB) has been feasibly investigated for the remediation of PG. The present study evaluated fluorine immobilization mechanisms and attempted to construct a related thermodynamic and geochemical modeling to describe the related stabilization performance. Physico-chemical and mineralogical analyses were performed on PG and hardened PG-based CPB (PCPB). The correlated macro- and microstructural properties were obtained from the analysis of the combination of unconfined compressive strength and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy imaging. Acid/base-dependent leaching tests were performed to ascertain fluoride leachability. In addition, Gibbs Energy Minimization Software and PHREEQC were applied as tools to characterize the PCPB hydration and deduce its geochemical characteristics. The results proved that multiple factors are involved in fluorine stabilization, among which the calcium silicate hydrate gel was found to be associated with retention. Although the quantitative comparison with the experimental data shows that further modification should be introduced into the simulation before being used as a predictive implement to determine PG management options, the importance of acid/base concentration in regulating the leaching behavior was confirmed. Moreover, the modeling enabled the identification of the impurity phases controlling the stability and leachability.

Keywords

cemented paste backfill / phosphogypsum / leaching behavior / fluoride

References

[1] Chen QS, Zhang QL, Qi CC, Fourie A, Xiao CC. Recycling phosphogypsum and construction demolition waste for cemented paste backfill and its environmental impact. J. Cleaner Prod., 2018, 186, 418.

[2] M. Tsioka and E.A. Voudrias, Comparison of alternative management methods for phosphogypsum waste using life cycle analysis, J. Cleaner Prod., 266(2020), art. No. 121386.

[3] Cordell D, Drangert JO, White S. The story of phosphorus: Global food security and food for thought. Glob. Environ. Change, 2009, 19(2): 292.

[4] Xu JP, Fan LR, Xie YC, Wu G. Recycling-equilibrium strategy for phosphogypsum pollution control in phosphate fertilizer plants. J. Cleaner Prod., 2019, 215, 175.

[5] Macías F, Pérez-López R, Cánovas CR, Carrero S, Cruz-Hernandez P. Environmental assessment and management of phosphogypsum according to European and United States of America regulations. Procedia Earth Planet. Sci., 2017, 17, 666.

[6] B. Geissler, L. Hermann, M. Mew, and G. Steiner, Striving toward a circular economy for phosphorus: The role of phosphate rock mining, Minerals, 8(2018), No. 9, art. No. 395.

[7] Rashad AM. Phosphogypsum as a construction material. J. Cleaner Prod., 2017, 166, 732.

[8] Yang L, Zhang YS, Yan Y. Utilization of original phosphogypsum as raw material for the preparation of self-leveling mortar. J. Cleaner Prod., 2016, 127, 204.

[9] Gorman MR, Dzombak DA. A review of sustainable mining and resource management: Transitioning from the life cycle of the mine to the life cycle of the mineral. Resour. Conserv. Recycl., 2018, 137, 281.

[10] Saadaoui E, Ghazel N, Ben Romdhane C, Massoudi N. Phosphogypsum: Potential uses and problems—A review. J. Environ. Stud., 2017, 74(4): 558.

[11] Li XB, Du J, Gao L, He SY, Gan L, Sun C, Shi Y. Immobilization of phosphogypsum for cemented paste backfill and its environmental effect. J. Cleaner Prod., 2017, 156, 137.

[12] Tayibi H, Choura M, López FA, Alguacil FJ, López-Delgado A. Environmental impact and management of phosphogypsum. J. Environ. Manage., 2009, 90(8): 2377.

[13] S.H. Yin, Y.J. Shao, A.X. Wu, Z.Y. Wang, and L.H. Yang, Assessment of expansion and strength properties of sulfidic cemented paste backfill cored from deep underground stopes, Constr. Build. Mater., 230(2020), art. No. 116983.

[14] Cheng HY, Wu SC, Zhang XQ, Wu AX. Effect of particle gradation characteristics on yield stress of cemented paste backfill. Int. J. Miner. Metall. Mater., 2020, 27(1): 10.

[15] Cao S, Xue GL, Yilmaz E, Yin ZY. Assessment of rheological and sedimentation characteristics of fresh cemented tailings backfill slurry. Int. J. Min. Reclam. Environ., 2021, 35(5): 319.

[16] Chen QS, Zhang QL, Fourie A, Xin C. Utilization of phosphogypsum and phosphate tailings for cemented paste backfill. J. Environ. Manage., 2017, 201, 19.

[17] X.L. Xue, Y.X. Ke, Q. Kang, Q.L. Zhang, C.C. Xiao, F.J. He, and Q. Yu, Cost-effective treatment of hemihydrate phosphogypsum and phosphorous slag as cemented paste backfill material for underground mine, Adv. Mater. Sci. Eng., 2019(2019), art. No. 9087538.

[18] Min CD, Li XB, He SY, Zhou ST, Zhou YN, Yang S, Shi Y. Effect of mixing time on the properties of phosphogypsum-based cemented backfill. Constr. Build. Mater., 2019, 210, 564.

[19] X.B. Li, S.T. Zhou, Y.N. Zhou, C.D. Min, Z.W. Cao, J. Du, L. Luo, and Y. Shi, Durability evaluation of phosphogypsumbased cemented backfill through drying-wetting cycles, Minerals, 9(2019), No. 5, art. No. 321.

[20] Huang Y, Lin ZS. Investigation on phosphogypsum-steel slag-granulated blast-furnace slag-limestone cement. Constr. Build. Mater., 2010, 24(7): 1296.

[21] Singh M. Effect of phosphatic and fluoride impurities of phosphogypsum on the properties of selenite plaster. Cem. Concr. Res., 2003, 33(9): 1363.

[22] Kang WH, Kim EI, Park JY. Fluoride removal capacity of cement paste. Desalination, 2007, 202(1–3): 38.

[23] Boncukcuoğlu R, Yılmaz MT, Kocakerim MM, Tosunoğlu V. Utilization of borogypsum as set retarder in Portland cement production. Cem. Concr. Res., 2002, 32(3): 471.

[24] Kagne S, Jagtap S, Dhawade P, Kamble SP, Devotta S, Rayalu SS. Hydrated cement: A promising adsorbent for the removal of fluoride from aqueous solution. J. Hazard. Mater., 2008, 154(1–3): 88.

[25] Gopal V, Elango KP. Equilibrium, kinetic and thermodynamic studies of adsorption of fluoride onto plaster of Paris. J. Hazard Mater., 2007, 141(1): 98.

[26] Silveira BI, Dantas AEM, Blasques JEM, Santos RKP. Effectiveness of cement-based systems for stabilization and solidification of spent pot liner inorganic fraction. J. Hazard. Mater., 2003, 98(1–3): 183.

[27] K. Gijbels, H. Nguyen, P. Kinnunen, P. Samyn, W. Schroeyers, Y. Pontikes, S. Schreurs, and M. Illikainen, Radiological and leaching assessment of an ettringite-based mortar from ladle slag and phosphogypsum, Cem. Concr. Res., 128(2020), art. No. 105954.

[28] Hwaiti MA. Influence of treated waste phosphogypsum materials on the properties of ordinary Portland cement. Bangladesh J. Sci. Ind. Res., 2015, 50(4): 241.

[29] Tsakiridis PE, Oustadakis P, Agatzini-Leonardou S. Black dross leached residue: An alternative raw material for Portland cement clinker. Waste Biomass Valorization, 2014, 5(6): 973.

[30] Dartan G, Taspinar F, Toroz İ. Analysis of fluoride pollution from fertilizer industry and phosphogypsum piles in agricultural area. J. Ind. Pollut. Control, 2017, 33(1): 662

[31] Adimalla N, Marsetty SK, Xu PP. Assessing groundwater quality and health risks of fluoride pollution in the Shasler Vagu (SV) watershed of Nalgonda. India, Hum. Ecol. Risk Assess., 2020, 26(6): 1569.

[32] Tang XQ, Wu M, Dai XC, Chai PH. Phosphorus storage dynamics and adsorption characteristics for sediment from a drinking water source reservoir and its relation with sediment compositions. Ecol. Eng., 2014, 64, 276.

[33] M.W. Wang, L. Liu, H.J. Li, Y.G. Li, H.L. Liu, C.C. Hou, Q. Zeng, P. Li, Q. Zhao, L.X. Dong, G.Y. Zhou, X.C. Yu, L. Liu, Q. Guan, S. Zhang, and A.G. Wang, Thyroid function, intelligence, and low-moderate fluoride exposure among Chinese school-age children, Environ. Int., 134(2020), art. No. 105229.

[34] Burnett WC, Elzerman AW. Nuclide migration and the environmental radiochemistry of Florida phosphogypsum. J. Environ. Radioact., 2001, 54(1): 27.

[35] Tafu M, Chohji T. Reaction between calcium phosphate and fluoride in phosphogypsum. J. Eur. Ceram. Soc., 2006, 26(4–5): 767.

[36] Jamieson HE, Walker SR, Parsons MB. Mineralogical characterization of mine waste. Appl. Geochem., 2015, 57, 85.

[37] X.B. Li, Y.N. Zhou, Q.Q. Zhu, S.T. Zhou, C.D. Min, and Y. Shi, Slurry preparation effects on the cemented phosphogypsum backfill through an orthogonal experiment, Minerals, 9(2019), No. 1, art. No. 31.

[38] Lothenbach B, Kulik DA, Matschei T, Balonis M, Baquerizo L, Dilnesa B, Miron GD, Myers RJ. Cemdata18: A chemical thermodynamic database for hydrated Portland cements and alkali-activated materials. Cem. Concr. Res., 2019, 115, 472.

[39] Wagner T, Kulik DA, Hingerl FF, Dmytrieva SV. Gem-selektor geochemical modeling package: Tsolmod library and data interface for multicomponent phase models. Can. Mineral., 2012, 50(5): 1173.

[40] Kulik DA, Wagner T, Dmytrieva SV, Kosakowski G, Hingerl FF, Chudnenko KV, Berner UR. GEM-Selektor geochemical modeling package: Revised algorithm and GEMS3K numerical kernel for coupled simulation codes. Comput. Geosci., 2013, 17(1): 1

[41] Parkhurst DL, Appelo CAJ. Description of input and examples for PHREEQC version 3—A computer program for speciation, batch-reaction, one-dimensional transport, and inverse geochemical calculations. U.S. Geological Survey Techniques and Methods, 2013, Denver, U.S. Geological Survey, 497 book 6, chap. A43

[42] Scholz RW, Ulrich AE, Eilittä M, Roy A. Sustainable use of phosphorus: A finite resource. Sci. Total Environ., 2013, 462, 799.

[43] Q.S. Chen, Q.L. Zhang, C.C. Xiao, and X. Chen, Backfilling behavior of a mixed aggregate based on construction waste and ultrafine tailings, PLoS One, 12(2017), No. 6, art. No. e0179872.

[44] Jiao HZ, Wang SF, Wu AX, Shen HM, Wang JD. Cementitious property of NaAlO₂-activated Ge slag as cement supplement. Int. J. Miner. Metall. Mater., 2019, 26(12): 1594.

[45] F.B. Chen, B. Xu, H.Z. Jiao, X.M. Chen, Y.L. Shi, J.X. Wang, and Z. Li, Triaxial mechanical properties and microstructure visualization of BFRC, Constr. Build. Mater., 278(2021), art. No. 122275.

[46] Jiao HZ, Wu YC, Wang W, Chen XM, Wang YF, Liu JH, Feng WT. The micro-scale mechanism of metal mine tailings thickening concentration improved by shearing in gravity thickener. J. Renewable Mater., 2021, 9(4): 637.

[47] Chen QS, Zhang QL, Fourie A, Chen X, Qi CC. Experimental investigation on the strength characteristics of cement paste backfill in a similar stope model and its mechanism. Constr. Build. Mater., 2017, 154, 34.

[48] Y. He, Q.L. Zhang, Q.S. Chen, J.W. Bian, C.C. Qi, Q. Kang, and Y. Feng, Mechanical and environmental characteristics of cemented paste backfill containing lithium slag-blended binder, Constr. Build. Mater., 271(2021), art. No. 121567.

[49] Y.X. Yang, T.Q. Zhao, H.Z. Jiao, Y.F. Wang, and H.Y. Li, Potential effect of porosity evolution of cemented paste backfill on selective solidification of heavy metal ions, Int. J. Environ. Res. Public Health, 17(2020), No. 3, art. No. 814.

[50] E.H. Perkins, Y.K. Kharaka, W.D. Gunter, and J.D. DeBraal, Geochemical modeling of water-rock interactions using SOLMINEQ.88, [in] Chemical Modeling of Aqueous Systems II, American Chemical Society, Washington, p. 117.

[51] J.D. Allison, D.S. Brown, and K.J. Novo-Gradac, Minteqa2/Prodefa2, a Geochemical Assessment Model for Environmental Systems: Version 3.0 User’s Manual, Environmental Protection Agency, Athens [2019-10-01]. https://www.osti.gov/biblio/5673069

[52] Garrabrants AC, Sanchez F, Kosson DS. Changes in constituent equilibrium leaching and pore water characteristics of a Portland cement mortar as a result of carbonation. Waste Manage., 2004, 24(1): 19.

[53] E. Martens, D. Jacques, V.G. Tom, L. Wang, and D. Mallants, PHREEQC modelling of leaching of major elements and heavy metals from cementitious waste forms, MRS Online Proc. Lib., 1107(2008), art. No. 475.

[54] Sowa WA. Interpreting mean drop diameters using distribution moments. Atomization Sprays, 1992, 2(1): 1.

[55] S.F. Lütke, M.L.S. Oliveira, L.F.O. Silva, T.R.S. Cadaval, and G.L. Dotto, Nanominerals assemblages and hazardous elements assessment in phosphogypsum from an abandoned phosphate fertilizer industry, Chemosphere, 256(2020), art. No. 127138.

[56] Jia CY, Wu LC, Chen QS, Ke P, De Yoreo JJ, Guan BH. Structural evolution of amorphous calcium sulfate nanoparticles into crystalline gypsum phase. CrystEngComm, 2020, 22(41): 6805.

[57] Ennaciri Y, Zdah I, El Alaoui-Belghiti H, Bettach M. Characterization and purification of waste phosphogypsum to make it suitable for use in the plaster and the cement industry. Chem. Eng. Commun., 2020, 207(3): 382.

[58] Y.B. Jiang, K.D. Kwon, S.F. Wang, C. Ren, and W. Li, Molecular speciation of phosphorus in phosphogypsum waste by solid-state nuclear magnetic resonance spectroscopy, Sci. Total Environ., 696(2019), art. No. 133958.

[59] L’ocsei B. Mullite formation in the aluminium fluoride-silica system (AlF₃-SiO₂). Nature, 1961, 190(4779): 907.

[60] Norwood VM, Kohler JJ. Characterization of fluorine-, aluminum-, silicon-, and phosphorus-containing complexes in wet-process phosphoric acid using nuclear magnetic resonance spectroscopy. Fertil. Res., 1991, 28(2): 221.

[61] Nishikawa T, Suzuki K, Ito S, Sato K, Takebe T. Decomposition of synthesized ettringite by carbonation. Cem. Concr. Res., 1992, 22(1): 6.

[62] Grounds T, Midgley HG, Novell DV. Carbonation of ettringite by atmospheric carbon dioxide. Thermochim. Acta, 1988, 135, 347.

[63] Jiang JY, Zheng Q, Hou DS, Yan YR, Chen H, She W, Wu SP, Guo D, Sun W. Calcite crystallization in the cement system: Morphological diversity, growth mechanism and shape evolution. Phys. Chem. Chem. Phys., 2018, 20(20): 14174.

[64] Šavija B, Luković M. Carbonation of cement paste: Understanding, challenges, and opportunities. Constr. Build. Mater., 2016, 117, 285.

[65] Holanda FDC, Schmidt H, Quarcioni VA. Influence of phosphorus from phosphogypsum on the initial hydration of Portland cement in the presence of superplasticizers. Cem. Concr. Compos., 2017, 83, 384.

[66] Bishop M, Bott SG, Barron AR. A new mechanism for cement hydration inhibition: Solid-state chemistry of calcium nitrilotris(methylene)triphosphonate. Chem. Mater., 2003, 15(16): 3074.

[67] Park JY, Byun HJ, Choi WH, Kang WH. Cement paste column for simultaneous removal of fluoride, phosphate, and nitrate in acidic wastewater. Chemosphere, 2008, 70(8): 1429.

[68] Guan W, Zhao X. Fluoride recovery using porous calcium silicate hydrates via spontaneous Ca²⁺ and OH⁻ release. Sep. Purif. Technol., 2016, 165, 71.

[69] S.V. Tarali, N.P. Hoolikantimath, N. Kulkarni, and P.A. Ghorpade, A novel cement-based technology for the treatment of fluoride ions, SN Appl. Sci., 2(2020), No. 7, art. No. 1205.

[70] Ghorpade PA, Ha MG, Park JY. Effect of different types of calcium sulfate on the reactivity of cement/Fe(II) system in dechlorination of trichloroethylene. Desalin. Water Treat., 2015, 54(4–5): 1426.

[71] G. Diamantopoulos, M. Katsiotis, M. Fardis, I. Karatasios, S. Alhassan, M. Karagianni, G. Papavassiliou, and J. Hassan, The role of titanium dioxide on the hydration of Portland cement: A combined NMR and ultrasonic study, Molecules, 25(2020), No. 22, art. No. 5364.

[72] Lothenbach B, Pelletier-Chaignat L, Winnefeld F. Stability in the system CaO-Al₂O₃-H₂O. Cem. Concr. Res., 2012, 42(12): 1621.

[73] Han JD, Pan GH, Sun W, Wang CH, Cui D. Application of nanoindentation to investigate chemomechanical properties change of cement paste in the carbonation reaction. Sci. China Technol. Sci., 2012, 55(3): 616.

[74] Peter MA, Muntean A, Meier SA, Böhm M. Competition of several carbonation reactions in concrete: A parametric study. Cem. Concr. Res., 2008, 38(12): 1385.