Rau Titanium Immersion Rhaub Tso rau hauv Molten Sulfur Tank (135 degree, Muaj Hydrogen Sulfide thiab Polysulfides), Vim Li Cas Phab Ntsa Thicker Tsis Muaj txiaj ntsig vim Corrosion yog Uniform thiab lub neej yog txiav txim siab los ntawm tag nrho cov hlau tawg?

Qhov Kev Lag Luam Tseem Ceeb hauv Titanium Heater Tsim rau Kev Pabcuam hauv Molten Sulfur
Molten sulphur tanks are maintained at 135°C to keep sulphur in liquid form for transportation or processing. The sulfur is saturated with hydrogen sulfide (H₂S) and polysulfides (H₂S_x) in solution. Titanium immersion heaters are utilized because titanium has strong resistance to sulphur and sulphides at moderate temperatures. However, titanium corrodes in molten sulfur by a chemical process: Ti + 2S ->TiS₂ Cov corrosion zoo ib yam, tsis pitting los yog tawg nyob rau hauv ib cheeb tsam. Tus nqi yog li 0.05-0.15 hli / xyoo nyob ntawm H2S cov ntsiab lus. Txij li thaum corrosion tsis sib xws, tag nrho cov hlau poob (phab ntsa thinning) dictates lub cua sov lub neej. Ntau phab ntsa thickness txhais tau tias proportionately ntau lub neej. Ob zaug ntawm phab ntsa thickness txhais tau tias ob zaug lub neej kev pab cuam. Tab sis tsis muaj qhov pib thickness hauv qab no uas corrosion accelerates, los yog saum toj no uas nws nres. (Nrog pitting, cov phab ntsa tuab muab qhov txo qis rov qab .) Qhov kev tshawb fawb no qhia qhov laj thawj ntawm qhov yooj yim linear scaling nyob rau hauv cov ntaub ntawv ntawm uniform corrosion thiab optimum thickness ntawm phab ntsa (1.5-2.0 mm) nyob rau hauv cov ntaub ntawv ntawm molten sulfur pab.

Mechanism ntawm Uniform Corrosion: cuam tshuam rau Mechanical Integrity
Cov titanium nto tau pom ncaj qha cuam tshuam nrog sulfur thiab polysulfides hauv molten sulfur ntawm 135 degree, ua rau tsim cov titanium disulfide (TiS2). TiS 2 txheej yog tiv thaiv tab sis maj mam yaj los yog tawg tawm los ntawm cov molten sulfur ntws. Tus nqi corrosion raws li linear kinetics: d=kt, qhov twg k yog 0.05–0.15 mm / xyoo. Tsis muaj qhov pib ua rau cov yeeb yaj kiab tsis zoo, tsis muaj qhov kub thiab txias rau pitting thiab tsis muaj kev cuam tshuam rau kev ntxhov siab corrosion. Lub corrosion yog zoo ib yam nyob rau hauv tag nrho cov immersed nto.

Tsis muaj kev tawm tsam hauv zos, yog li lub sijhawm rau perforation tsuas yog: t_perf=(pib phab ntsa thickness) / (corrosion rate). Yog tias tus nqi corrosion yog 0.10 hli / xyoo, 1.2 hli phab ntsa yuav perforated nyob rau hauv 12 xyoo. 15 xyoo rau 1.5 hli phab ntsa. 20 xyoo rau phab ntsa 2.0 hli tuab. Kev sib raug zoo yog ib txoj kab ncaj nraim. Yog li ntawd, phab ntsa tuab yog qhov zoo ntawm qhov ncaj qha rau cov khoom siv ntxiv. Tus nqi ntawm titanium, txawm li cas los xij, zoo ib yam mus linearly nrog tuab. Tsis muaj qhov txiaj ntsig nonlinear mus rau tuab heev.

Thermal Performance Impact: Thaum tshav kub kub hloov txim
Lub phab ntsa tuab ua rau me me tab sis tus nqi thermal tiag tiag. Rau ib tug raug kub flux ntawm 2.0 W / cm $ ^ 2$, lub convective kuj dominates nyob rau hauv molten sulfur (h $ \\ approx $ 500 W / m $ ^ 2$ K vim siab viscosity). Rau 1.2 hli phab ntsa R_cond=7.1e-5; rau 2.0 hli phab ntsa R_cond=1.18e-4. Tag nrho cov kev tiv thaiv tau nce los ntawm 8%, yog li qhov kub ntawm qhov saum npoo yog nce los ntawm 2-3 degree. Qhov no ua rau kom tus nqi corrosion me ntsis (qee 10% rau 3'C nce), me ntsis cuam tshuam qhov zoo ntawm phab ntsa tuab. Tag nrho cov txiaj ntsig ntawm kev nce ntawm 1.2 hli mus rau 2.0 hli yog qhov txuas ntxiv ntawm lub neej los ntawm 12 xyoo mus rau ib ncig ntawm 18 xyoo (tsis yog 20 xyoo vim qhov kub thiab txias). Txoj cai ntawm kev txo qis rov qab tuav, txawm tias tsis muaj zog.

Kev Lag Luam - tawm ntawm Phab Ntsa Thickness thiab Kev Pabcuam Lub Neej
Phab ntsa Thickness (mm) Corrosion Rate ntawm 135℃(mm/yr) Kub Acceleration Factor Effective Corrosion Rate (mm/yr) Lub Sijhawm rau Perforation (xyoo) Cov Khoom Siv Tus Nqi 1.0 hli 0.10 1.00 × 0.10 10 xyoo 1.0 × 1.2 mm 0.10 1.02 × {1.} × 2} xyoo 0.105 14.3 xyoo 1.5 × 1.8 hli 0.10 1.08 × 0.108 16.7 xyoo 1.8 × 2.0 hli 0.10 1.10 × 0.110 18.2 xyoo 2.0 × 2.5 hli 0.10 1.15 × 0.115 21.7 xyoo 2.5 ×
Ib phab ntsa 2.0 hli tuab muaj kev pab cuam lub neej ntawm 18 xyoo, 80% ntev dua phab ntsa 1.0 hli tuab, tab sis nrog 100% cov khoom siv ntau dua. 1.5 hli phab ntsa xa 14 xyoo ntawm 50% kev siv nyiaj ntau dua, feem ntau yog qhov zoo tshaj plaws ntawm kev lag luam.

Engineering tom qab Phab Ntsa: Kev Tswj Xyuas Kub thiab Zoo ntawm Sulfur
Lub H₂S concentration nyob rau hauv molten sulfur yog ib tug rhiab heev parameter rau tus nqi corrosion. Nyob rau hauv ntshiab sulfur (low H2S), tus nqi qis li 0.03 mm / xyoo. Qos sulfur nrog siab H2S thiab polysulfide tuaj yeem siab li 0.25 hli / xyoo. Yog hais tias cov sulfur zoo tsis zoo, yuav tsum muaj phab ntsa tuab, tab sis ib txoj hauv kev zoo dua yog kom sparge cov sulfur tank nrog nitrogen rau sawb H2S, txo qhov corrosion ntawm 70-80%. Nitrogen Sparging 30+ Xyoo 1.2mm Phab Ntsa Kev Tswj Kub Kub kuj tseem ceeb: txo qhov kub ntawm lub tank los ntawm 135℃mus rau 125℃txo qhov corrosion ntawm ib ncig ntawm 40%, uas tso cai rau cov phab ntsa nyias nyias.

Xaus: Linear Benefit-Xaiv phab ntsa ua lub luag haujlwm ntawm lub neej thiab tus nqi
Lub phab ntsa tuab yog pab tau rau lub titanium immersion rhaub nyob rau hauv lub molten sulfur tank ntawm 135℃nrog H2S thiab polysulfides raws li cov corrosion yog uniform thiab lub neej nyob ntawm tag nrho cov hlau yaj. Doubling phab ntsa thickness roughly doubles lub neej kev pab cuam (nrog me ntsis nplua los ntawm kub acceleration). Pom zoo phab ntsa thickness: 1.2-1.5 hli rau 10 xyoo ntawm lub neej; 1.5-1.8 hli rau 15 xyoo ntawm lub neej; 2.0-2.5 hli rau 20 xyoo ntawm lub neej. Tsis muaj qhov cuam tshuam (cov phab ntsa tuab tsis ua haujlwm). Kev xaiv kev lag luam zoo tshaj plaws yog feem ntau 1.5 hli, uas muab 14 xyoo lub neej ntawm 50% ntau tshaj 1.0 hli phab ntsa. Muab qhov kwv yees kwv yees ntawm H₂S thiab qhov ntsuas kub ua haujlwm rau cov chaw tsim khoom kom tso cai rau lawv suav cov nqi corrosion pes tsawg. Nyob rau hauv cov ntaub ntawv ntawm molten sulfur kev pab cuam phab ntsa thickness yog ib tug ncaj linear tsim variable. Thicker zoo dua tab sis kim dua -xaiv lub neej xav tau.