Biomass productivity

Biological—Biochemical Processes. Fermentation is a biological process in which a water slurry or solution of raw material interacts with microorganisms and is enzymatically converted to other products. Biomass can be subjected to fermentation conditions to form a variety of products. Two of the most common fermentation processes yield methane and ethanol. Biochemical processes include those that occur naturally within the biomass. 

In passive attack, biological material acts as a chemically inert substance. Wastage is an indirect consequence of the biological mass or biological by-products. Biomass acts as any deposit accumulation would,... 

Biomass Production. Biomass is usually measured by dry weight of viable cells per unit volume X. We bypass the sometimes tricky problems associated with this measurement except to say that it is the province of the microbiologist and usually involves plate cultures and filtration followed by drying. Suppose there is one limiting nutrient S, and that all other nutrients are available in excess. Then the Monod model for growth is... 

DOE, Hydrogen, Fuel Cells and Infrastructure Technologies Program, Multi-year Research, Development and Demonstration Plan. 2003 available at http //wwwl.eere.energy.gov/hydrogenandfuelcells/ production/biomass gasification.html (accessed March 2008). 

Reynolds CS, Descy JP (1996) The production, biomass and structure of phytoplankton in large rivers. Arch fur Hydrobiol Suppl 113 161-187... 

Culture Product Biomass (g/1 dry wt) Time (days) Yield (% dry wt) Yield (g/1) Productivity (g/1/day) Refer- ences... 

Pyrolysis is the degradation of macromolecular materials with heat alone in the absence of oxygen [45]. The development of pyrolysis processes for the production of liquids has gained much attention in the last decade because they offer a convenient way to convert low-value woody residues into liquid fuels and value-added products. Biomass pyrolysis is of growing interest as the liquid product can be stored and easily transported [46]. Pyrolysis processes yield a mixture of gas, liquid, and solid products. If pyrolysis is practiced alone, that is, without a subsequent gasification step (see Section 16.4.3), the process conditions are usually chosen to maximize liquid product yields. 

Hallam, A. Anderson, I.C. Buxton, D.R. Comparative economic analysis of perennial and annual intercrops for biomass production. Biomass Bioenerg. 2001, 21, 407-424. 

The following equations describe a general form of the model for the fed-batch process and total medium, having only substrate as feed flow, and include mass balances for substrate, product, biomass, and kinetic relations, respectively. 

Several special terms are used to describe traditional reaction engineering concepts. Examples include yield coefficients for the generally fermentation environment-dependent stoichiometric coefficients, metabolic network for reaction network, substrate for feed, metabolite for secreted bioreaction products, biomass for cells, broth for the fermenter medium, aeration rate for the rate of air addition, vvm for volumetric airflow rate per broth volume, OUR for 02 uptake rate per broth volume, and CER for C02 evolution rate per broth volume. For continuous fermentation, dilution rate stands for feed or effluent rate (equal at steady state), washout for a condition where the feed rate exceeds the cell growth rate, resulting in washout of cells from the reactor. Section 7 discusses a simple model of a CSTR reactor (called a chemostat) using empirical kinetics. 

Gunnarson, S., Malmberg, A., Mathisen, B., Theander, O., Thyselis, L., and Wunsche, U., Jerusalem artichoke (Helianthus tuberosus L.) for biogas production, Biomass, 1, 85-97, 1985. 

Soderstrom, J., Pilcher, L., Galbe, M., and Zacchi, G. 2003. Two-step steam pretreatment of softwood by dilute H2S04 impregnation for ethanol production, Biomass Bioenergy, 24,475 186. 

Montane, D., Salvado, J., Torras, C., and Farriol, X., High-temperature dilute-acid hydrolysis of olive stones for furfural production. Biomass Bioenergy 2002, 22 (4), 295-304. 

Dote Y.. Inoue S.. Ogi T. and Yokoyama S. (1996) Studies on the direct liquefaction of protein-coiitaincd biomass The distribution of nitrogen m the products. Biomass Bioenergv. 11 (6)491-498... 

Russell J.M., Miller R.K Molton P. (1983) Formation of Aromatic Compounds from Condensation Reactions of Cellulose Degradation Products. Biomass, 3, 43-57. 

Capacity of the plant Fermentation volume Productivity Biomass concentration Ethanol concentration Acetic acid concentration Substrate consumption Ethanol in pervaporate Inlet dilution rate Product dilution rate Medium bleed rate Cell bleed rate Recirculation rate Pervaporation area Microfiltration area Investment fermentor Investment distillation Investment pervaporation Investment microfiltration Total capital cost Depreciation membranes Molasses and nutrients Steam Electricity Process water Cooling water Total production costs... 

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