000			02073nab a2200205 4500
005			20260520001029.0
008			260224s2011 xxu
245	0	0	_aEffect of relative humidity on ammonium chloride corrosion in refineries
260			_a _b _cmayo 2011
270			_a19/05/2011 ; 19/05/2011
300			_a7 p. ; 055005
520			_aTranscripción del resumen del autor. Corrosion behavior and the hygroscopic properties of solid ammonium chloride (NH4Cl) salt were investigated. This study was conducted to determine the root cause of significant corrosion caused by NH4Cl salt deposition in reactor-effluent streams in hydroprocessing units. Corrosion and water absorption tests were performed under various relative humidity (RH) conditions with solid NH4Cl salts using a temperature and humidity control chamber. Eight types of materials commonly used in refineries were examined, including carbon steel (UNS K02702), Type 304 (UNS S30400) stainless steel, duplex (UNS S39274) stainless steel, Grade 2 titanium (UNS R50400), Alloy 400 (UNS N04400), Alloy C-276 (UNS N10276), aluminum brass (UNS C68700), and aluminized carbon steel (hot-dip aluminized UNS K02702). Significant corrosion was observed around 60% RH on all the alloys except Alloy C-276. Carbon steel corroded above 20% RH. Its highest corrosion rate was observed at 60% RH and 80°C. Type 304 stainless steel and duplex stainless steel showed pitting at 50% and 60% RH. Although the metal surface on Alloy C-276 was tarnished at 50% RH, it had excellent corrosion resistance at all RH levels. It was suggested that the corrosion of NH4Cl is the most severe around a critical RH, above which water absorption becomes significant. In addition, based on the water absorption tests and simulation results, it was found that the critical RH of NH4Cl salt has a close relationship to temperature.
581			_a5
773	0		_tCorrosion _g67
942			_cARTICULO
100	1		_aToba, K. _949899
100	1		_aSuzuki, T. _949900
100	1		_aKawano, K. _949901
999			_c181829 _d181829