A Pilot-Plant Investigation of Factors Affecting Low-Temperature Corrosion in Oil-Fired Boilers

1965 ◽  
Vol 87 (2) ◽  
pp. 197-202
Author(s):  
R. C. Attig ◽  
P. Sedor
Keyword(s):  
High Temperature ◽  
Carbon Steel ◽  
Low Temperature ◽  
Corrosion Rate ◽  
Pilot Plant ◽  
Metal Temperature ◽  
Flue Gases ◽  
Factors Affecting ◽  
Excess Air ◽  
Future Work

Methods for controlling or eliminating low-temperature corrosion are continually being sought to improve boiler availability and thermal efficiency. A small pilot plant was constructed at the authors’ company in which factors that affect low-temperature corrosion could be studied under closely controlled conditions. Results of tests on this unit show that: (a) The corrosion rate on carbon steel increases gradually as metal temperature falls below the acid dewpoint, passing through a peak at a metal temperature about 200 F. The corrosion rate then decreases as metal temperature continues to fall but begins to rise rapidly to extremely high values at temperatures just above the water dewpoint (⋍ 120 F). (b) Low-temperature corrosion of carbon steel can be practically eliminated if a method can be found for reducing the sulfur content of oil to about 0.5 percent. (c) The application of low-excess-air operation has the potential of eliminating low-temperature corrosion in boiler plants firing high-sulfur residual oils. (d) Corrosion of carbon steel above approximately 170 F can be reduced 30 percent or more by recirculating 25 percent of the flue gases to the burner. Future work will include a study of the effect of low-excess-air operation on high-temperature oil-ash corrosion and deposition and on the effect of oil ash on low-temperature corrosion.

Corrosion behavior of carbon steel in H2S-CO2-H2O-methyldiethanolamine (MDEA) solution under the presence of chloride ions

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Guiyang Wu ◽  
Xikui Gu ◽  
Wanwei Zhao ◽  
Rui Fan ◽  
Ting Mao
Keyword(s):  
High Temperature ◽  
Carbon Steel ◽  
Low Temperature ◽  
Corrosion Rate ◽  
Corrosion Behavior ◽  
Electrochemical Impedance ◽  
Chloride Ion ◽  
Chloride Ions ◽  
Corrosion Products ◽  
Content Type

Purpose This paper aims to study the effect of chloride ions concentration on the corrosion behavior of carbon steel in methyldiethanolamine (MDEA) aqueous solution in the sight of different process parameters of purification plant. Design/methodology/approach Due to the decrease of filtration efficiency and separation efficiency, the chloride ion in the desulfurization solution is enriched. The corrosion behavior of carbon steel under chloride ion enrichment environment was studied by weight-loss method, electrochemical impedance spectroscopy, cyclic polarization curve, X-ray photoelectron spectroscopy and scanning electron microscopy. Findings The results show that temperature and hydrogen sulfide loads are the main factors of corrosion in CO2-MDEA-H2O-H2S environment. The enrichment of chloride ions reduces the corrosion rate at low temperature but promotes the corrosion rate at high temperature. The chloride concentration should be controlled below 3000 mg/L, and no pitting corrosion was found under the experimental conditions. Originality/value The effect of chloride ion enrichment on MDEA solution corrosion shows that at low temperature, the increase of chloride ion will reduce the acid gas load and increase the density of corrosion products, so as to reduce the corrosion; on the contrary, at high temperature, the density of corrosion products will decrease and the corrosion will be intensified as well. It is believed that the chloride ion should be controlled below 3000 mg/L according to the results of the tests.

Synchroshear Versus Conventional Shear Mechanisms in Transitionmetal Disilicides with the C40 Structure

1999 ◽  
Vol 578 ◽  
Author(s):  
H. Inui ◽  
M. Yamaguchi
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Plastic Flow ◽  
Deformation Mechanism ◽  
Deformation Behavior ◽  
Basal Slip ◽  
Room Temperature ◽  
Onset Temperature ◽  
Factors Affecting ◽  
Temperature Group

AbstractThe deformation behavior of (0001) <1210> basal slip in single crystals of five different transitionmetal disilicides with the C40 structure has been investigated in the temperature range from room temperature to 1500°C in compression. These disilicides are found to be classified into two groups depending on the onset temperature for plastic flow. The low-temperature group, which consists of VSi2, NbSi2 and TaSi2, exhibits the onset temperature for plastic flow around 0.3 T/Tm (melting temperature) and deforms by a conventional shear mechanism. In contrast, the high temperature group, which consists of CrSi2 and Mo(Si,Al)2, exhibits the onset temperature around 0.6T/Tm and deforms by a synchroshear mechanism. Factors affecting the deformation mechanism in these C40 disilicides are discussed in terms of directionality of atomic bonding and the relative stability of the C40 phase with respect to the C11b phase.

Influence of the Compressive Stress on the Corrosion of Petroleum Casing Premium Connection Material

2012 ◽  
Vol 512-515 ◽  
pp. 1919-1922
Author(s):  
Cheng Xian Yin ◽  
Xin Hu Wang
Keyword(s):  
Stainless Steel ◽  
High Temperature ◽  
Carbon Steel ◽  
Yield Strength ◽  
Corrosion Rate ◽  
Compressive Stress ◽  
Water Solution

In order to find the corrosion cause of petroleum casing premium connection material, the fixture was design to simulate material enduring compressive stress, and the fixture was put in high temperature autoclave, and the corrosion rate of two kind casing material(carbon steel and stainless steel) enduring compressive stress were test in H2S and CO2 and Cl- water solution. The result was that compressive stress accelerated the corrosion of petroleum casing steel, and when compressive stress was greater than the value half as the yield strength the corrosion rate increased quickly.

scholarly journals The Exploitation of Low-Temperature Hot Water Boiler Sources with High-Temperature Heat Pump Integration

Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6311
Author(s):  
Darko Goričanec ◽  
Igor Ivanovski ◽  
Jurij Krope ◽  
Danijela Urbancl
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Heat Pump ◽  
Flue Gas ◽  
Hot Water ◽  
Flue Gases ◽  
Excess Heat ◽  
Heating Water ◽  
Temperature Heat ◽  
High Temperature Heat Pump

The article presents an original and innovative technical solution for the exploitation of low-temperature excess heat from hot water boilers that use gas or liquid fuel for the needs of high-temperature heating in buildings or in industry. The primary fuel efficiency used for hot water boilers can be significantly increased by utilizing the excess low-temperature heat of flue gases that are discharged into the environment and thus also reduce CO2 emissions. Hot water systems usually operate at higher temperatures of the heating water, which is transported to the heat consumer via supply pipe, and the cooled heating water is returned to the hot water boiler via the return pipe. For the excess low-temperature heat exploitation of the flue gases from hot water boiler, it is necessary to install a condenser in the flue gas discharge pipe, where condensation of water vapour present in the flue gas heats water or a mixture of water and glycol. The heating water, which is cooled and returned from the heat consumer via the return pipe, is led to the condenser of the high-temperature heat pump, where it is preheated and then led to the hot water boiler, where it is heated to the final temperature. A computer simulation with the Aspen plus software package for the series or parallel connection of high-temperature heat pump to a hot water heating system and the economic analysis of the excess heat exploitation from the flue gases are also performed.

Exsolution and inversion in pigeonite from the Whin Sill, Northern England

1978 ◽  
Vol 36 (1) ◽  
pp. 474-475
Author(s):  
P.P.K. Smith
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Homogeneous Nucleation ◽  
Silicate Mineral ◽  
Antiphase Boundaries ◽  
Two Phase ◽  
Primitive Form ◽  
The Core ◽  
Nucleation Mechanisms ◽  
And Inversion

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.

Effects of Particle Size Distribution on Corrosion Rate of Carbon Steel in Soil

2020 ◽  
Vol 69 (4) ◽  
pp. 102-106
Author(s):  
Shota Ohki ◽  
Shingo Mineta ◽  
Mamoru Mizunuma ◽  
Soichi Oka ◽  
Masayuki Tsuda
Keyword(s):  
Particle Size ◽  
Carbon Steel ◽  
Corrosion Rate ◽  
Particle Size Distribution ◽  
Size Distribution
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