Working volume

When the volume of reaeting mixture ehanges proportionately with eonversion, as in the ease of gas phase reaetions, this implies working volume ehanges with time. 

A solution containing 0.25 kmol/m of acetic anhydride is to be hydrolyzed in a single CFSTR to give an effluent containing an anhydride concentration of 0.05 kmol/m. The volumetric flowrate is 0.05 m /min and the working volume of the reactor is 0.75 m. ... 

The growth of Mehylomonas L3 on methanol was observed in a CSTR. Working volume of the tank was V = 0.355 L. The eon-eentration of methanol in fresh medium was 1 g/L. The results of the experiment at a steady state are given in the following table [24]. 

In sealing-up a bateh reaetor plant to a fuh-seale eommereial plant, every full-size reaetor in the plant will have a working volume, whieh is some multiple of the eapaeity of a pilot plant reaetor. The produetion of the full-seale plant is usually predieted from eyele times experieneed in the small-seale plant (see Chapter 4). 

Consider the reaetor in Figure 13-1 with defined geometrie eon-figurations, the working volume Wy is expressed as ... 

Assume that the total area of the bottom head is effeetive for heat transfer. Therefore, the total surfaee area of tlie reaetor in Eigure 13-1 available for heating or eooling the working volume is defined by... 

The working volume ean be defined using Equation 13-12 or it ean be defined as related to the straight side length that it oeeupies. Making this expression in J equal to Equation 13-12 with eonstants as expressed by Equation 13-14 gives... 

Using the data in Example 13-2, determine the aspeet ratio for the same eooling time (0.85 hr) as the larger unit, with the working volume twiee that of the pilot plant seale of a segmented bateh reaetor. 

Fraetion of the total volume oeeupied by the working volume. Mass flowrate, Ib/hr ft ... 

Heating jaeket flowrate, Ib/hr Flow rate to a zone, Ib/hr Working volume, gal... 

There are numerous possible applications for air curtains. For example, air curtains may be used to heat a body of linear dimensions (as used to move the fresh snow from the railway exchanges in Canada) to function as a partition between two parts of one volume to function as a partition between an internal room and an external environment, that have different thermodynamic properties and to shield an opening in a small working volume (see Section 10.4.6). 

The CSD from an MSMPR crystallizer with a working volume of 10 m operated with a magma density of 250 kg crystals/m slurry and a production rate of 62 500 kg crystals/h has a mass mean size of 480 pm. Calculate ... 

Eastman Kodak Company (1983). Ergonomics Design for People at Work, Volume 1. New York Van Nostrand Reinhold. 

Bohr, N. [1977] Collected works, volume 4, in J. Rud Nielsen (ed.) North-Holland, Amsterdam. 

The production-scale fermentation unit, with a projected annual capacity of over50,000 tonnes was fully commissioned in 1980. The bioreactor (Figure 4.8) is 60 m high, with a 7 m base diameter and working volume 1,500 m3. There are two downcomers and cooling bundles at the base. Initial sterilisation is with saturated steam at 140°C followed by displacement with heat sterilised water. Air and ammonia are filter sterilised as a mixture, methanol filter sterilised and other nutrients heat sterilised. Methanol is added through many nozzles, placed two per square metre. For start-up, 20 litres of inoculum is used and the system is operated as a batch culture for about 30 h. After this time the system is operated as a chemostat continuous culture, with methanol limitation, at 37°C and pH 6.7. Run lengths are normally 100 days, with contamination the usual cause of failure. 

Conventional stirred reactors with working volumes of 50 to 150 m3 have been used routinely for citric add production whereas tower bioreactors, currently 200 m and larger (greater than 600 m3) are envisaged. 

A 3 litre bioreactor with a working volume of 2 litre is inoculated with the three shaking flasks. The pH is maintained at 5.5 by automatic titration with 5mol l 1 NH4OH and the temperature is held at 37°C. 

A reasonable size of bioreactor, based on transport and handling considerations, is 200 m3, with a working volume of 150 m3. If file fermentation time is 48 hours and down time for reuse about 24 hours, then the total batch time is 72 hours. 

The above correlation is valid for a bioreactor size of less than 3000 litres and a gassed power per unit volume of 0.5-10 kW. For non-coalescing (non-sticky) air-electrolyte dispersion, the exponent of the gassed power per unit volume in the correlation of mass transfer coefficient changes slightly. The empirical correlation with defined coefficients may come from the experimental data with a well-defined bioreactor with a working volume of less than 5000 litres and a gassed power per unit volume of 0.5-10 kW. The defined correlation is ... 

Generally residence time is obtained by division of working volume by volumetric flow rate. 

Effective agitation is required for uniform distribution of substrate and microbes in the working volume of the bioreactor. 

A 20 m3 working volume of a bioreactor is used for producting penicillin. What would be the sugar concentration (S0) you choose if oxygen transfer rate is not the limiting reactant Given data ... 

The inoculate was prepared in 250 ml flasks containing 100 ml of growth medium, which is inoculated with 10 ml of spore suspension. The mixture was shaken at 250 rpm and the temperature was controlled at 26 °C for 48 h. Then, 110 ml of resulting mycelia suspension is used to inoculate a 1000 ml broth in the airlift fermenter. The sterilised media are slowly pumped into the bioreactor at a flow rate of about lOOmlh-1 until 2 1 working volume is fully utilised. Aeration rates of 0.5, 1 and 2vvm (1,2 and 4 1 air/min) are used.6,7 Samples were taken at 24 hour intervals and evaluated for biomass, sugars and antibiotic concentrations. 

A 2 IB. Braun airlift fermenter with a working volume of about 2000 ml was used. Sterile air is sparged through a sintered plate located near the bottom of the central concentric tube. There was no mechanical stirring only the air nozzle was forced through the centred tube and the flow directed to the annulus tube side. Aeration causes circulation of media the flow is gentle without serious shear forces. The temperature is maintained at 26 °C. 

The control of these and any other parameters is most usually done in fermenter vessels specifically designed for the purpose and accommodating various working volumes, depending on the yield and production requirements. Laboratory-scale vessels could have a capacity of just 10 litres or less whereas clinical trials and production vessels may be as large as several thousand litres. 

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