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Carbonate-bicarbonate carbon steel

Carbon steel Concentrated caustic Concentrated nitrate solutions Anhydrous ammonia Carbonate and bicarbonate solutions... [Pg.206]

Fig. 8.11 Effect of beam deflection rate of cantilever beam specimens upon stress-corrosion crack velocity of carbon steel in carbonate-bicarbonate solution... Fig. 8.11 Effect of beam deflection rate of cantilever beam specimens upon stress-corrosion crack velocity of carbon steel in carbonate-bicarbonate solution...
The activated carbonate process is based on absorption of CO2 by potassium carbonate to give potassium bicarbonate (configuration 2). When potassium bicarbonate is heated it releases CO2 while potassium carbonate is formed back again. The original hot carbonate process was found too corrosive for carbon steel reactor walls. Nowadays, however, improvements in additives and optimisation of operation have made activated carbonate processes competitive with state-of-the-art MDEA systems. [Pg.21]

Hard waters contain high concentrations of calcium and bicarbonate and steel samples exposed to hard waters result in the deposition of calcium carbonate deposit on the steel... [Pg.204]

High solids (carbonates and bicarbonates) BFW will result in significant formation of carbon dioxide. The resulting carbon dioxide-laden condensate causes erosion-corrosion attack on carbon steel. Failure occurs by deep pitting, furrowing, or channeling. Corrosion inhibitors can be added to minimize this attack. [Pg.20]

Figure 7.79 illustrates the influence of alloy composition on the potential dependence of the failure-time ratio of carbon steel in a carbonate-bicarbonate environment (Ref 116, 117). The failure-time ratio is... [Pg.376]

Strain-rate dependence of ductility of the form shown in Fig. 7.81 is presented in Fig. 7.82 for a carbon steel in a carbonate-bicarbonate environment (Ref 119). The ductility is represented as the ratio of the reduction in area (RA) in the environment relative to the value in inert oil. The tests were conducted at the indicated constant potentials and illustrate that the strain-rate dependence can be sensitive to the potential, particularly the minimum ductility and the strain rate at which the minimum occurs. It follows, as an illustration, that if small changes in the environment, such as dissolved oxygen, shift the potential from -720 to -680 mV (SHE), significant changes in susceptibility to SCC would be predicted. [Pg.379]

SCC occurs due to the presence of a weak passive film in the active potential region [48,49,165]. SCC of carbon steel in hot carbonate/bicarbonate solution is an example of zone 2 SCC in the active potential region [166]. Proportionality between CGR and anodic dissolution current was studied by Parkins [48,49]. As shown in Fig. 9.45, a linear correlation was found between CGRs and anodic current densities [49]. [Pg.413]

F ure 1138 Effect of the temperature of heat treatments on hydrogen cracking susceptibility of quenched carbon steel (0.25% C) cathodically polarized at a potential of -0.14 V in carbonate-bicarbonate solution at 90 °C. Shown is the ratio of the reduction in area measured in the corrosive environment to that measured in a non-corrosive environment (oil) in SCC tests... [Pg.495]

Carbon steels Caustic NaOH solutions seawater calcium, ammonium, and sodium nitrate solutions HCN solutions acidified H2S solutions anhydrous liquid ammonia carbonate/bicarbonate CO/CO2 solutions... [Pg.748]

A A state of imperfect passivity near an active-passive transition, e.g., carbon steel in aqueous hydroxide, nitrate, or carbonate-bicarbonate solutions [26,27]. [Pg.417]

Operating Problems. In the initial tests made by the U.. Bureau of Mines, severe corrosion of carbon steel was encountered, especially where the conversion to bicarbonate was high or where carbon dioxide and steam were released by pressure reduction (Bienstock and Field, 1961). Potassium dichromate was found to be an effective corrosion inhibitor, and 0.2% was used in the solution for subsequent C02-absoiption tests. This material is recommended as a corrosion inhibitor only for plants handling sulfur-free gas. Concentrations of 1,000 to 3,000 ppm have been found satisfactory for commercial installations. [Pg.359]

As previously stated, a 40% solution has been found to be too concentrated for commercial use in some cases because of its tendency to form a slurry of bicarbonate crystals if the solution is cooled at any point in the circuit. In the presence of bicarbonate slurry, carbon steel cases and impellers of pumps were found to last only a few hours. Reduction of the solution concentration to below 30% eliminates this severe erosion however, stainless steel (type 316) impellers, case rings, and throat bushings are recommended in pumps handling the K2CO3 solution as a further safety measure (Buck and Leitch, 1958). [Pg.362]

Manufacture. Aqueous sodium hydroxide, sodium bicarbonate, sodium carbonate, or sodium sulfite solution are treated with sulfur dioxide to produce sodium metabisulfite solution. In one operation, the mother Hquor from the previous batch is reinforced with additional sodium carbonate, which need not be totally in solution, and then is treated with sulfur dioxide (341,342). In some plants, the reaction is conducted in a series of two or more stainless steel vessels or columns in which the sulfur dioxide is passed countercurrent to the alkaH. The solution is cooled and the sodium metabisulfite is removed by centrifuging or filtration. Rapid drying, eg, in a stream-heated shelf dryer or a flash dryer, avoids excessive decomposition or oxidation to which moist sodium metabisulfite is susceptible. [Pg.149]

Aikaiinity Bicarbonate (HCOs" ), carbonate (COs , and hydroxyl (OH ), expressed as CaCOs Foaming and carryover of solids with steam embrittlement of boiler steel bicarbonate and carbonate produce CO2 in steam, a source of corrosion Lime and lime-soda softening, acid treatment, hydrogen zeolite softening, demineralization, dealkalization by anion exchange, distillation, degasifying... [Pg.146]

Aikaliniry Bicarbonates (HCOd Carbonates (CO,) Hydroxyl (OH) as CaCO, Steam systems foaming and solid carry over Steel embrittlement (HCO,) and (CO,) Corrosion Distillation Demineralization I..ime and lime soda Dealkalization I lon exchange) Acid treatment liydrogcn zeolire... [Pg.149]

Steels Nitrate ion Sti ong alkali Carbonate/bicarbonate Liquid ammonia Hydrogen sulfide (aqueous) Cyanide ion... [Pg.894]

The most important property of the dissolved solids in fresh waters is whether or not they are such as to lead to the deposition of a protective film on the steel that will impede rusting. This is determined mainly by the amount of carbon dioxide dissolved in the water, so that the equilibrium between calcium carbonate, calcium bicarbonate and carbon dioxide, which has been studied by Tillmans and Heublein and others, is of fundamental significance. Since hard waters are more likely to deposit a protective calcareous scale than soft waters, they tend as a class to be less aggressive than these indeed, soft waters can often be rendered less corrosive by the simple expedient of treating them with lime (Section 2.3). [Pg.500]

Various workers have used equation 8.8, or some modified version thereof, to compare observed with calculated crack velocities as a function of strain rate, but Fig 8.8 shows results from tests on a ferritic steel exposed to a carbonate-bicarbonate solution. The calculated lines move nearer to the experimental data as the number of cracks in equation 8.9 is increased, while the numbers of cracks observed varied with the applied strain rate, being about 100 for 4pp 10 s , but larger at slower 4pp and smaller at higher 4pp. [Pg.1166]

Fig. 8.21 Current density dilTerences between fast and slow sweep rate polarisation curves and stress corrosion cracking suspectiblity as a function of potential for a C-Mn steel in nitrate, hydroxide and carbonate-bicarbonate solutions... Fig. 8.21 Current density dilTerences between fast and slow sweep rate polarisation curves and stress corrosion cracking suspectiblity as a function of potential for a C-Mn steel in nitrate, hydroxide and carbonate-bicarbonate solutions...

See other pages where Carbonate-bicarbonate carbon steel is mentioned: [Pg.1169]    [Pg.1176]    [Pg.1377]    [Pg.431]    [Pg.20]    [Pg.326]    [Pg.104]    [Pg.74]    [Pg.494]    [Pg.496]    [Pg.1202]    [Pg.1209]    [Pg.1410]    [Pg.607]    [Pg.1309]    [Pg.1163]    [Pg.1164]    [Pg.1164]    [Pg.1180]    [Pg.1181]    [Pg.1183]    [Pg.1187]    [Pg.1187]    [Pg.1191]    [Pg.1237]    [Pg.1366]    [Pg.1378]    [Pg.778]   
See also in sourсe #XX -- [ Pg.379 ]




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