Thaum Qib 2 Titanium Heater Tube raug rau Humid Ammonia Vapor ntawm 150 degree, Yuav Ua Li Cas Ammonium Hydroxide Concentration hauv Condensate Film Hloov Cov Hydrogen Absorption Rate thiab Lub Sijhawm Ncua Ua Li Cas?

Nyob rau hauv cov av noo ammonia vapor ntawm 150 \\u00b0C, dej condensation tshwm sim ntawm titanium rhaub nto, tsim ib txheej nyias uas absorbs NH3 los tsim ammonium hydroxide (NH4OH). Tus nqi ntawm NH_{4}OH nyob rau hauv zaj duab xis ntawm condensate nyob ntawm tus txheeb ze humidity thiab lub siab ib nrab ntawm NH_{3}. NH4OH yog alkaline (pH 10 ~ 12) thiab ua rau cov titanium passive txheej, ua kom yooj yim nqus hydrogen. Lub hydrogen uptake nce thiab lub sij hawm tawg incubation txo nrog NH4OH concentration.

Hydrogen absorption vs NH4OH concentration (quantitative)

NH4OH Concentration in Condensate (wt%) pH Hydrogen Absorption Rate (ppm/1,000h) Crack Incubation Time (hours) 0 (clean water) 7 5–15 >10,000 1 10 20–40 3,000–6,000 5 11 50–100 1,000–2,500 10 12 100–200 400–1,000 20 12.5 200–400 150–400 Kev kub ntxhov ntawm NH4OH Aggressiveness

Kub (degree) NH₄OH 10% – H Absorption (ppm/1,000h) NH₄OH 10% – Crack Incubation (teev) 100 60–120 800–1,500 150 100–{8}}–1,000
200 180-350 200-500 NH4OH phau ntawv qhia kev tswj hwm kev xav

Condensate NH₄OH (%) Pom Zoo Ua Haujlwm Lub Neej Cia Siab (1.5 hli phab ntsa)
<1 None >10 xyoo 1-5 Lower humidity or NH₃ 5-10 years
5-10 Purging nrog inert gas 2-5 xyoo10 Tsis tau txais-rov tsim dua<2 years
Pom zoo Engineering

Rau cov av ammonia vapor kev pab cuam, txwv cov txheeb ze humidity rau<50%, and NH₃ partial pressure to <0.1 atm, to maintain condensate NH₄OH <5%. The engineer restricts ammonium hydroxide concentration to lower hydrogen absorption and increase crack incubation period.