A new generation of bioreactors
Many biotech companies use stirred tank reactors as a central apparatus in their processes. But these stirred reactors use much energy, and energy make up a significant part of the cost of producing products with low value per share. device. A new type of fermenter is possibly the solution to this problem. Read the original article here
In any bioprocess play bioreactor, the so-called fermenter, a central role, and construction panasonic air conditioner and operation of fermenters are therefore subject of intense study. One can achieve significant udbyttte- and production improvements by a detailed study of the micro-organism physiology, overall described by "Metabolic Engineering '[1], panasonic air conditioner by optimizing the fermentation medium or by selecting panasonic air conditioner the appropriate process conditions. But there is also a need for a more comprehensive assessment, where a number of engineering problems treated. It is particularly important for products that are made in large volume, and where the price per. volume product is low, for example. in the production of Single Cell Protein (SCP), amino acids, and industrial enzymes. In these processes, the fermentation can be up to 50% of the total production costs. Much of the cost is due to the energy panasonic air conditioner used by admixing of liquid feed to the reactor for the transfer of a feed component (eg. O 2) from the gas phase to the liquid phase and for cooling the contents of the reactor.
Fermenters in Denmark Most Danish biotech companies use a technology where the suspended cells of bacteria, yeasts or filamentous fungi stirred (steel) tanks, while the gas phase is blown in through nozzles at the bottom of the tank. The fermentation medium should be as homogeneous as possible, and the substrates to be fed at the rate which maximize selectivity and productivity. It is a difficult task on a large scale: down-blending of liquid substrate is not good in the up to 200 m3 large industrial fermenters, and oxygen is supplied and is not recorded with sufficient speed in the liquid phase. A survey in 1999 conducted by BioCentrum Engineering showed that the total fermentorkapacitet in Danish biotech panasonic air conditioner companies was approximately 15,000 m3 with an expected increase to 20,000 m3 in 2005. With an annual operating time of 7,000 hours and with a power consumption of 4.2 kW m- 3 corresponded in 1999 to 450 GWh year-1 and an accompanying CO2 output of 212,000 tons. A quick summary of the stirred tankreaktors panasonic air conditioner operating conditions shows why energy is so large, and one can also point out where improvements can be made.
The stirred tankreaktors limitations Ideally, the liquid phase must be completely mixed, but on industrial scale it is difficult to provide the required power thereto. This leads to gradients in the example. sugar and oxygen concentrations in the liquid, the pH and the temperature. Continuous fermentation is based on the addition of sugar in a very concentrated form (300 kg m-3), but if the sugar concentration is less than about 20 g m-3 in the reactor, panasonic air conditioner is the enzyme yield of sugar, for example. to almost nothing. In addition, the mixing ensure a good dispersion of the feed gas so as to obtain a large surface area per day. m3 reactor and thus a good mass transport. Mixing occurs often using Rushton turbines [2], superposed with 2-3 m distance in large fermenters. Each turbine panasonic air conditioner provides a good agitation in a zone around the turbine, and to provide an axial mixing is often other omrørertyper at the bottom or at the top of the reactor. Even the most modern down-pumping propeller strong panasonic air conditioner instabilities which may result in an undesirable rapid wear of the mixing device [3]. Another undesirable consequence of the conventional fermentorkonstruktioner is that the cooling surface, panasonic air conditioner which usually is made up of tubes mounted on the reactor inner wall is not adequate in large fermentors, the surface area per. m3 reactor volume decreases with V-1 / 3rd An obvious improvement of fermentorkonstruktionen is to let the heat exchange system outside the fermenter in a recirculation loop.
Other fermentorkonstruktioner As an alternative to mechanically agitated fermenters are a number of other fermentortyper panasonic air conditioner developed as described in [4]. Bubble Columns used in a number of major productions such. of citric acid (550,000 tonnes year-1), but when the energy supply is made only through the bubble dispersion at the bottom of the fermenter, these devices may be used only if the oxygen supply per. consumed sugar is low. The effectiveness of bubble panasonic air conditioner columns can be increased if the gas is supplied in one of two tall, slim leg of a loop fermentor. At the top the residual gas is released, and the liquid sink because. Specific gravity panasonic air conditioner difference into the second leg. This creates a degree of liquid circulation, but the utilization of oxygen from the gas phase is low, 20-40%, and no other energy is applied, one of which is dispersed through gasindblæsningen, one can not achieve small gas bubbles in the mechanically stirred reactor. The gas is supplied through a two-fluid nozzle, where the tearing up of a simultaneous input
Many biotech companies use stirred tank reactors as a central apparatus in their processes. But these stirred reactors use much energy, and energy make up a significant part of the cost of producing products with low value per share. device. A new type of fermenter is possibly the solution to this problem. Read the original article here
In any bioprocess play bioreactor, the so-called fermenter, a central role, and construction panasonic air conditioner and operation of fermenters are therefore subject of intense study. One can achieve significant udbyttte- and production improvements by a detailed study of the micro-organism physiology, overall described by "Metabolic Engineering '[1], panasonic air conditioner by optimizing the fermentation medium or by selecting panasonic air conditioner the appropriate process conditions. But there is also a need for a more comprehensive assessment, where a number of engineering problems treated. It is particularly important for products that are made in large volume, and where the price per. volume product is low, for example. in the production of Single Cell Protein (SCP), amino acids, and industrial enzymes. In these processes, the fermentation can be up to 50% of the total production costs. Much of the cost is due to the energy panasonic air conditioner used by admixing of liquid feed to the reactor for the transfer of a feed component (eg. O 2) from the gas phase to the liquid phase and for cooling the contents of the reactor.
Fermenters in Denmark Most Danish biotech companies use a technology where the suspended cells of bacteria, yeasts or filamentous fungi stirred (steel) tanks, while the gas phase is blown in through nozzles at the bottom of the tank. The fermentation medium should be as homogeneous as possible, and the substrates to be fed at the rate which maximize selectivity and productivity. It is a difficult task on a large scale: down-blending of liquid substrate is not good in the up to 200 m3 large industrial fermenters, and oxygen is supplied and is not recorded with sufficient speed in the liquid phase. A survey in 1999 conducted by BioCentrum Engineering showed that the total fermentorkapacitet in Danish biotech panasonic air conditioner companies was approximately 15,000 m3 with an expected increase to 20,000 m3 in 2005. With an annual operating time of 7,000 hours and with a power consumption of 4.2 kW m- 3 corresponded in 1999 to 450 GWh year-1 and an accompanying CO2 output of 212,000 tons. A quick summary of the stirred tankreaktors panasonic air conditioner operating conditions shows why energy is so large, and one can also point out where improvements can be made.
The stirred tankreaktors limitations Ideally, the liquid phase must be completely mixed, but on industrial scale it is difficult to provide the required power thereto. This leads to gradients in the example. sugar and oxygen concentrations in the liquid, the pH and the temperature. Continuous fermentation is based on the addition of sugar in a very concentrated form (300 kg m-3), but if the sugar concentration is less than about 20 g m-3 in the reactor, panasonic air conditioner is the enzyme yield of sugar, for example. to almost nothing. In addition, the mixing ensure a good dispersion of the feed gas so as to obtain a large surface area per day. m3 reactor and thus a good mass transport. Mixing occurs often using Rushton turbines [2], superposed with 2-3 m distance in large fermenters. Each turbine panasonic air conditioner provides a good agitation in a zone around the turbine, and to provide an axial mixing is often other omrørertyper at the bottom or at the top of the reactor. Even the most modern down-pumping propeller strong panasonic air conditioner instabilities which may result in an undesirable rapid wear of the mixing device [3]. Another undesirable consequence of the conventional fermentorkonstruktioner is that the cooling surface, panasonic air conditioner which usually is made up of tubes mounted on the reactor inner wall is not adequate in large fermentors, the surface area per. m3 reactor volume decreases with V-1 / 3rd An obvious improvement of fermentorkonstruktionen is to let the heat exchange system outside the fermenter in a recirculation loop.
Other fermentorkonstruktioner As an alternative to mechanically agitated fermenters are a number of other fermentortyper panasonic air conditioner developed as described in [4]. Bubble Columns used in a number of major productions such. of citric acid (550,000 tonnes year-1), but when the energy supply is made only through the bubble dispersion at the bottom of the fermenter, these devices may be used only if the oxygen supply per. consumed sugar is low. The effectiveness of bubble panasonic air conditioner columns can be increased if the gas is supplied in one of two tall, slim leg of a loop fermentor. At the top the residual gas is released, and the liquid sink because. Specific gravity panasonic air conditioner difference into the second leg. This creates a degree of liquid circulation, but the utilization of oxygen from the gas phase is low, 20-40%, and no other energy is applied, one of which is dispersed through gasindblæsningen, one can not achieve small gas bubbles in the mechanically stirred reactor. The gas is supplied through a two-fluid nozzle, where the tearing up of a simultaneous input
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