Release of toxic gases in the process of cemented backfill with phosphorus waste

Abstract

Aiming at the practical problem of toxic gases generated in the process of cemented backfill with phosphorus waste (phosphogypsum as aggregate and yellow phosphorus slag as the binder), sources and dynamics of gas generation and the method of gas inhibition were investigated by monitoring the gas generated in the aggregate, the binder and the cemented slurry stirring process. The main findings proved that the gases were mainly generated from the binder in an acidic circumstance, and the gas generation sequence is PCl₃, PH₃, NO, H₂S, NH₃, and CO. Furthermore, lowering the pH value of the cemented slurry would increase the gas yield. The original gas yield of the slurry without acid addition was only 6.3% of the maximum gas yield after acid addition. By analyzing the circumstances of gas generation, a method of directly adding alkaline CaO to the slurry to control the gas generation was proposed. The addition of 12 wt% CaO was noted to reduce the gas yield by 99%. When the pH of the backfill slurry reached 10, the gas generation could be controlled. The results have implications for ensuring the health of mining workers and decreasing environmental pollution.

Keywords

toxic gas / phosphogypsum / cemented backfill / pH value / gas inhibitor

References

[1] ChenQ, DingW, PengT, et al. . Synthesis and characterization of calcium carbonate whisker from yellow phosphorus slag [J]. Open Chemistry, 2020, 18(1): 347-356

[2] GuK, ChenB. Loess stabilization using cement, waste phosphogypsum, fly ash and quicklime for self-compacting rammed earth construction [J]. Construction and Building Materials, 2020, 231: 117195

[3] CuadriA A, NavarroF J, García-MoralesM, et al. . Valorization of phosphogypsum waste as asphaltic bitumen modifier [J]. Journal of Hazardous Materials, 2014, 27911-16

[4] DegirmenciN. Utilization of phosphogypsum as raw and calcined material in manufacturing of building products [J]. Construction and Building Materials, 2008, 22(8): 1857-1862

[5] LiY, LuoX, LiC, et al. . Variation of alkaline characteristics in bauxite residue under phosphogypsum amendment [J]. Journal of Central South University, 2019, 26(2): 361-372

[6] RashadA M. Phosphogypsum as a construction material [J]. Journal of Cleaner Production, 2017, 166: 732-743

[7] SahooP, JosephJ. Radioactive hazards in utilization of industrial by-products: Comprehensive review [J]. Journal of Hazardous, Toxic, and Radioactive Waste, 2021, 25(3): 03121001

[8] LiuH, MaL, HuangX, et al. . Phase transformation of glass-ceramics produced by naturally cooled yellow phosphorus slag during calcination [J]. Journal of Alloys and Compounds, 2017, 712: 510-516

[9] ChenJ, ZhaoB, WangX, et al. . Cemented backfilling performance of yellow phosphorus slag [J]. International Journal of Minerals, Metallurgy, and Materials, 2010, 17(1): 121-126

[10] SuY, LiG, XiaJ. Kinetic study of Fe removal from precipitated silica prepared from yellow phosphorus slag [J]. The Canadian Journal of Chemical Engineering, 2009, 87(4): 610-613

[11] DongL, DengS, WangF. Some developments and new insights for environmental sustainability and disaster control of tailings dam [J]. Journal of Cleaner Production, 2020, 269122270

[12] LiG, LinH, MaY, et al. . Experimental study of purifying precipitated silica produced from yellow phosphorus slag [J]. Advanced Materials Research, 2012, 455–456503-506

[13] MinC, ShiY, LiuZ. Properties of cemented phosphogypsum (PG) backfill in case of partially substitution of composite Portland cement by ground granulated blast furnace slag [J]. Construction and Building Materials, 2021, 305: 124786

[14] ShiY, ChengL, TaoM, et al. . Using modified quartz sand for phosphate pollution control in cemented phosphogypsum (PG) backfill [J]. Journal of Cleaner Production, 2021, 283124652

[15] TianT, KeW, ZhuF, et al. . Effect of substrate amendment on alkaline minerals and aggregate stability in bauxite residue [J]. Journal of Central South University, 2019, 26(2): 393-403

[16] LiX, ZhouZ, ZhaoG, et al. . Utilization of phosphogypsum for backfilling, way to relieve its environmental impact [J]. Gospodarka Surowcami Mineralnymi-Mineral Resources Management, 2008, 24(4): 223-232

[17] CaoZ, LiuB, LiX, et al. . Experimental study on backfilling mine goafs with chemical waste phosphogypsum [J]. Geofluids, 2019, 20199218916

[18] LiX, ZhouY, ZhuQ, et al. . Slurry preparation effects on the cemented phosphogypsum backfill through an orthogonal experiment [J]. Minerals, 2019, 9(1): 31

[19] YinT, YangR, DuJ, et al. . Effects of acid and phosphate on arsenic solidification in a phosphogypsum-based cement backfill process [J]. RSC Advances, 2019, 94828095-28101

[20] KasapT, YilmazE, GunerN U, et al. . Recycling dam tailings as cemented mine backfill: Mechanical and geotechnical properties [J]. Advances in Materials Science and Engineering, 2022, 20221-12

[21] KasapT, YilmazE, SariM. Physico-chemical and micro-structural behavior of cemented mine backfill: Effect of pH in dam tailings [J]. Journal of Environmental Management, 2022, 314: 115034

[22] SariM, YilmazE, KasapT, et al. . Strength and microstructure evolution in cemented mine backfill with low and high pH pyritic tailings: Effect of mineral admixtures [J]. Construction and Building Materials, 2022, 328127109

[23] XueG, YilmazE. Strength, acoustic, and fractal behavior of fiber reinforced cemented tailings backfill subjected to triaxial compression loads [J]. Construction and Building Materials, 2022, 338127667

[24] YanB, JiaH, YilmazE, et al. . Numerical investigation of creeping rockmass interaction with hardening and shrinking cemented paste backfill [J]. Construction and Building Materials, 2022, 340127639

[25] ShiY, GanL, LiX, et al. . Dynamics of metals in backfill of a phosphate mine of Guiyang, China using a three-step sequential extraction technique [J]. Chemosphere, 2018, 192354-361

[26] LiX, DuJ, GaoL, et al. . Immobilization of phosphogypsum for cemented paste backfill and its environmental effect [J]. Journal of Cleaner Production, 2017, 156: 137-146

[27] Wojtacha-RychterK, SmolińskiA. Research on a gas index reflecting the sorption process on carbon materials in coal mines [J]. Sustainability, 2018, 10(7): 2468

[28] ZhengC, KizilM S, ChenZ, et al. . Effects of coal properties on ventilation air leakage into methane gas drainage boreholes: Application of the orthogonal design [J]. Journal of Natural Gas Science and Engineering, 2017, 45: 88-95

[29] XueJ, ZhaoD, ChengJ, et al. . Sources of particular pollutants inAmbient air at a petrochemical enterprise [J]. China Petroleum Processing & Petrochemical Technology, 2013, 15(4): 33-37

[30] LiZ, WuG, ChenJ, et al. . A novel gas sensor detection of hydrogen sulfide in tunnel construction [J]. Science of Advanced Materials, 2019, 11(1): 147-151

[31] ChenQ, ZhangQ, FourieA, et al. . Utilization of phosphogypsum and phosphate tailings for cemented paste backfill [J]. Journal of Environmental Management, 2017, 20119-27

[32] KiragosyanK, PicardM, SorokinD Y, et al. . Effect of dimethyl disulfide on the sulfur formation and microbial community composition during the biological H₂S removal from sour gas streams [J]. Journal of Hazardous Materials, 2020, 386: 121916

[33] SanniS E, AgboolaO, FagbieleO, et al. . Optimization of natural gas treatment for the removal of CO₂ and H₂S in a novel alkaline-DEA hybrid scrubber [J]. Egyptian Journal of Petroleum, 2020, 29(1): 83-94

[34] ScholesC A, StevensG W, KentishS E. Membrane gas separation applications in natural gas processing [J]. Fuel, 2012, 9615-28

[35] MinC, LiX, HeS, et al. . Effect of mixing time on the properties of phosphogypsum-based cemented backfill [J]. Construction and Building Materials, 2019, 210: 564-573

[36] SongS, JenningsH M. Pore solution chemistry of alkali-activated ground granulated blast-furnace slag [J]. Cement and Concrete Research, 1999, 29(2): 159-170

[37] DimbourJ P, GilbertD, DandrieuxA, et al. . Assessment of the effectiveness of downward water sprays for mitigating gaseous chlorine releases in partially confined spaces [J]. Journal of Hazardous Materials, 2003, 96(2–3): 127-141

[38] FanH, ZhangS, LiB, et al. . Control of sulfur-containing gas during drying of sludge [J]. Bulletin of the Chinese Ceramic Society, 2017, 36(3): 888-892(in Chinese)

[39] HanJ W, HassoliN, LeeK S, et al. . Dry scrubbing of gaseous HCl and SO₂ with hydrated lime in entrained mixing reactor [J]. Powder Technology, 2021, 393: 471-481

[40] JuliastutiS R, HendrianieN, DianP Y, et al. . Reduction of P₂O₅ and F from phosphogypsum by CaO addition [J]. MATEC Web of Conferences, 2018, 156: 03021

[41] KimM S, JunY B, LeeC H, et al. . Use of CaO as an activator for producing a price-competitive non-cement structural binder using ground granulated blast furnace slag [J]. Cement and Concrete Research, 2013, 54208-214

[42] SeoJ, ParkS, YoonH N, et al. . Effect of CaO incorporation on the microstructure and autogenous shrinkage of ternary blend Portland cement-slag-silica fume [J]. Construction and Building Materials, 2020, 249: 118691

[43] KangX, SuY, ZhaoY, et al. . Study on Fe leaching kinetic in the acid solution process of yellow phosphorus slag [J]. Bulletin of the Chinese Ceramic Society, 2012, 31(6): 1367-1370(in Chinese)

[44] DegirmenciN, OkucuA, TurabiA. Application of phosphogypsum in soil stabilization [J]. Building and Environment, 2007, 42(9): 3393-3398

[45] HanC, GengJ, ZhangJ, et al. . Phosphine migration at the water-air interface in Lake Taihu, China [J]. Chemosphere, 2011, 82(6): 935-939

[46] JungH, KangJ, ChunH, et al. . First principles computational study on hydrolysis of hazardous chemicals phosphorus trichloride and oxychloride (PCl₃ and POCl₃) catalyzed by molecular water clusters [J]. Journal of Hazardous Materials, 2018, 341457-463

[47] GBZ 2.1-2007. Occupational exposure limits for hazardous agents in the workplace. Part 1: Chemical hazardous agents [S].