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MATERIAL AND ELEMENTAL BALANCES FOR ENZYMES

Rendell C. Barcimo, RChE, MEE Chemical Engineering Department College of Engineering and Technology University of St. La Salle

MATERIAL AND ELEMENTAL BALANCE What would the respiration quotient be?
 What fraction of substrate is consumed and how much substrate is converted to biomass and end products? 
 If the process is aerobic, how much O is required? 
 2

What would the oxygen transfer rate (OTR) be? 


MATERIAL AND ELEMENTAL BALANCE ➤

All microorganisms require nutrients for propagation and to produce metabolites as useful by-products

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C, H, N, S, P, Mg, Na, and K

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Trace metals and minerals: Fe, Cu, Zn, Co, Mn and Mo

ELEMENTAL BALANCE Cell growth and metabolic activities are similarly described as a simple chemical reaction.

ELEMENTAL BALANCE

ELEMENTAL BALANCE

ELEMENTAL BALANCE A batch process is customary for producing antibiotics. Submerged culture is used to propagate fungus with suitable carbohydrate resources. This assumption is based on simplicity in calculations and the normal use of penicillin in the pharmaceutical industry. Assume we are required to produce antibiotic, one kilomole of penicillin G (334 kg) per batch. The general equation for the production of penicillin G and biomass is: aC6H12O6 + bH2SO4 + cNH3 → dC16H18O4N2S + eCO2 + fH2O + gC4H7O3N Yields of product and biomass are 20% and 50%, respectively (YP/S=0.2, YX/S=0.5). Moles of penicillin G produced are based on a stoichiometric relation above. Solve for the coefficients.

MATERIAL BALANCE

In - Out + Generation - Consumption = Accumulation

MATERIAL BALANCE In a continuous wastewater treatment plant, 105 kg of cellulose and 103 kg of bacteria enter into the digestion unit as feed stream on a daily basis, while 104 kg of cellulose and 1.5 x104 kg of bacteria leave in the effluent. The rate of cellulose digestion is 7x104 kg day-1. The bacterial growth rate is 2x104 kg day-1. The cell death rate by cell autolysis is 5x102 kg day-1. Do the material balance for cellulose and bacteria based on the given data.

MATERIAL BALANCE Humid air with O2 is prepared for a gluconic acid fermentation. The humid air has been prepared by a special humidification chamber where 1.5 l/h of liquid water enters; at the same time dry air and 15 mol/min dry O2 enters the chamber. The exiting gas stream contains 1% (w/w) water. Determine the flow rate of dry air needed.

MATERIAL BALANCE A fermentation broth containing Streptomyces kanamyceticus cells is filtered by a vacuum rotary filter. The feed rate is 120 kg h-1; each kilogram of broth contains 60 g of cells. To improve filtration, filter aids are added at a rate of 10 kg h-1. The concentration of kanamycin in the broth is 0.05%. The filtrate is collected at a rate of 112 kg h-1. The concentration of kanamycin in the filtrate is 0.045%. The filter cake contains cells, and filter aid is continuously removed from the filter cloth. (a) What is the moisture content in the filter cake?
 (b) If the concentration of kanamycin in the filter cake is the same as in the filtrate, how much kanamycin is absorbed per kilogram of filter aid?

MATERIAL BALANCE Corn steep liquor contains 2.5% invert sugars and 50% water. The rest of the feed is considered as residual solids. Beet molasses containing 50% sucrose, 1% invert sugar, 18% water and remainder solids are mixed with corn steep liquor in a mixing tank. Water is added to produce a diluted mixture with 2% invert sugar, 125 kg corn steep liquor and 45 kg molasses, which is fed into an enzymatic hydrolysis tank. (a) How much water is required?
 (b) What is the concentration of sucrose in the final mixture?