5.1. A medium is sterilized at 121°C for 15 minutes. If the initial number of spores is 10^6 per mL and the death rate constant is 0.5 min^-1, what is the final number of spores per mL?
Solution: Assuming no cell growth or death, the total amount of cells remains constant at 1000 g. After adding 500 L of medium, the total volume becomes 1500 L. The new cell concentration is 1000 g / 1500 L = 0.67 g/L. Bioprocess Engineering Basic Concepts 2nd Edition Solution
Solution: Power per unit volume = 2 kW / 2000 L = 0.001 kW/L or 1 W/L. Solution: Assuming no cell growth or death, the
Solution: Using the equation for sterilization, N(t) = N0 * e^(-kt), where N0 is the initial number of spores, k is the death rate constant, and t is time. N(15) = 10^6 * e^(-0.5*15) = 10^6 * e^(-7.5). Solution: Power per unit volume = 2 kW / 2000 L = 0
2.2. A fermentation process produces 200 kg of product per day. If the process operates 300 days per year, what is the annual production of product?
2.1. A bioreactor contains 1000 L of medium with an initial cell concentration of 1 g/L. If 500 L of medium is added, what is the new cell concentration?
4.1. A stirred-tank bioreactor has a volume of 2000 L and operates at a stirrer speed of 100 rpm. If the power input is 2 kW, what is the power per unit volume?