Carbon Monoxide Mass Transfer in a Syngas Mixture

Abstract

A myoglobin assay for measuring concentrations of dissolved carbon monoxide (CO) from an artificial synthesis gas blend (20% CO, 18% CO2, 52% N2, and 10% H2) was utilized to determine volumetric CO−water mass-transfer rates in a 0.211-m-diameter stirred-tank reactor (STR). The data are well correlated using the power density and superficial gas velocity, but this correlation is valid only for this STR size. A gas−liquid scale-up model developed for dissolved oxygen mass-transfer rates using air was used to develop a CO−liquid scale-up model for syngas fermentation. The model is applicable in the STR hydrodynamic range associated with after-large-cavity (ALC) formation and assumed to hold for other STR sizes. A myoglobin assay for measuring concentrations of dissolved carbon monoxide (CO) from an artificial synthesis gas blend (20% CO, 18% CO 2 , 52% N 2 , and 10% H 2 ) was utilized to determine volumetric CO-water masstransfer rates in a 0.211-m-diameter stirred-tank reactor (STR). The data are well correlated using the power density and superficial gas velocity, but this correlation is valid only for this STR size. A gas-liquid scaleup model developed for dissolved oxygen mass-transfer rates using air was used to develop a CO-liquid scale-up model for syngas fermentation. The model is applicable in the STR hydrodynamic range associated with after-large-cavity (ALC) formation and assumed to hold for other STR sizes.

Kinetics of CO conversion into H2 by Carboxydothermus hydrogenoformans

“…The cell culture density is limiting the CO conversion rate only when the cell concentration is low just after inoculation (Henstra 2006). However, because of the low aqueous solubility of CO, gasliquid mass transfer turns out to be the limiting step of CO conversion once the growth of biomass has been sufficient, as the volumetric bioactivity potential of the C. hydrogenoformans culture becomes limited by the dissolved CO available in the liquid (Cowger et al 1992;Kapic et al 2006;Riggs and Heindel 2006;J o n e s2007; Ungerman and Heindel 2007). Hence, for a thermophilic bioprocess to perform at a continuous maximal volumetric activity rate, it is essential for the cell concentration of the microorganism to be optimized to avoid the CO gas-liquid mass transfer limitation.…”

A Techno-economic Analysis of Polyhydroxyalkanoate and Hydrogen Production from Syngas Fermentation of Gasified Biomass

“…Although mass transfer rate coefficients, k L a, were expected to be a function of reactor diameter, stirring speed, etc. [16,17], there was not sufficient data to model this functional dependence based on the range of values used in this study. Instead, a constant k L a of 0.05 s −1 was used based on work of Kapic et al [16,17].…”

“…[16,17], there was not sufficient data to model this functional dependence based on the range of values used in this study. Instead, a constant k L a of 0.05 s −1 was used based on work of Kapic et al [16,17]. For the bioreactor optimization model, it was assumed that the working fluid was water.…”

“…Techno-economic analysis of PHA production by the gasification-based biorefinery will allow for the estimation of PHA production cost on a commercial scale and for the evaluation of the economic feasibility of PHA production. In this study, the biorefinery process was simulated based on the recently published information on the production and separation of PHA [4,[13][14][15][16][17][18][19][20][21][22].…”

A techno-economic analysis of syngas fermentation for the production of hydrogen and polyhydroxyalkanoate

“…The scale up from a laboratory size reactor to an industrial scale requires maintaining similarity between the two sizes of vessels [32]. First, geometric similarity must be maintained, which means the industrial scale vessel must be proportionate to the laboratory reactor.…”