Tuesday, March 2, 2010

Microchannel reactors.

Process technology "microchannel", what is it about this term?
In a laboratory scale, we can make contact reactions with solids such as gas in a tubular-shaped reactor diameter is less than one centimeter to micrometer size. Or in the catalyst technology, we use the material bearers (monolith), which has hundreds of small channels with dimensions uniformly. Microchannel reactor concept more or less similar to the set of tens and even hundreds of micro channel dimensions, regularity and relevance of each channel was designed so. Increasing the scale of the actual plant is merely increasing the number of micro channels.

If the wall is coated with a catalyst microchannel fluid flowing reactants will be in contact with the wall and there was a reaction microchannel. Dimensional microscopic channels could increase the contact surface area per unit volume and indirectly also increase the productivity per unit volume. Another advantage was reduced residence time of fluid in the micro reactor.

There is a fundamental difference between the technological process of "microchannel" with "microreactor". Microreactor technology means using a small reactor which is often used in laboratory tests. While microchannel technology intended to keep commercial production. Including such reactors, mixers, heat exchangers, which use micro channels to accommodate the flow and improve performance. Channel diameter dimensions varying from tens to hundreds of micrometers and can be several meters long. The fundamental difference is the microchannel components integrated into the system that contains tens to thousands of channels. Reducing the size of conventional production equipment with a more compact system such as microchannel known as the intensification of the process. The benefits are lower investment costs and energy efficiency.

According to experts from R.C. Costello & Associates, an engineering consultant in the United States, with a microchannel equipment, we can control the temperature to 0.1 degrees Celsius, which means that the reaction totally controlled and prevent "hot spots". Similarly, quality improvements in the distribution of heat and mass transfer process. Even in April of 2004 was such a big company Velocys, Dow Chemical and leading laboratories, the Pacific Northwest National Laboratory will apply in the production of ethylene and other olefins compounds.

Velocys now is developing microchannel technology for hydrogen production through the formation of steam from natural gas (methane). These reactors produce syngas - a mixture of carbon monoxide and hydrogen. Hydrogen production can be maximized through the "water gas shift reaction", ie the reaction of CO with water vapor at lower temperatures. Vapor formation process is endothermic requiring heat. Velocys utilizing heat from the combustion of methane occurs and excess hydrogen formed in the process of formation of steam. Endothermic or exothermic process and then combined. Each micro channel forming steam in the reactor is passed to the flow of hot combustion gases. Residence time in the reactor which caused a brief reaction temperature on the formation of steam and rapid cooling of the product. Heating and rapid cooling is required in this process in order to prevent the formation of carbon.

The combination of a compact between the formation of steam and combustion can quickly reach equilibrium at high temperatures and pressures. Secondly it shows achievement kedapat heat flux and rapid kinetics in microchannel reactors. Residence time can be reduced to 10 milliseconds - compared with a conventional reactor which takes 10 seconds. As a result, the volume of the entire system can be greatly reduced for the sake of efficiency.

Other studies utilizing microchannel reactors such as the production of methanol from syngas, the process of transforming natural gas into liquid hydrocarbons, and hydrogen peroxide production. Everything related to the processes that produce or require high temperatures. Latest technology that may be involved is the use of integrated nano catalysts in micro channels. In fact, small is not necessarily weak, because the gangs are small will also be strong even better than great, the challenge for the engineers in Indonesian.

Process technology "microchannel", what is it about this term?
In a laboratory scale, we can make contact reactions with solids such as gas in a tubular-shaped reactor diameter is less than one centimeter to micrometer size. Or in the catalyst technology, we use the material bearers (monolith), which has hundreds of small channels with dimensions uniformly. Microchannel reactor concept more or less similar to the set of tens and even hundreds of micro channel dimensions, regularity and relevance of each channel was designed so. Increasing the scale of the actual plant is merely increasing the number of micro channels.

If the wall is coated with a catalyst microchannel fluid flowing reactants will be in contact with the wall and there was a reaction microchannel. Dimensional microscopic channels could increase the contact surface area per unit volume and indirectly also increase the productivity per unit volume. Another advantage was reduced residence time of fluid in the micro reactor.

There is a fundamental difference between the technological process of "microchannel" with "microreactor". Microreactor technology means using a small reactor which is often used in laboratory tests. While microchannel technology intended to keep commercial production. Including such reactors, mixers, heat exchangers, which use micro channels to accommodate the flow and improve performance. Channel diameter dimensions varying from tens to hundreds of micrometers and can be several meters long. The fundamental difference is the microchannel components integrated into the system that contains tens to thousands of channels. Reducing the size of conventional production equipment with a more compact system such as microchannel known as the intensification of the process. The benefits are lower investment costs and energy efficiency.

According to experts from R.C. Costello & Associates, an engineering consultant in the United States, with a microchannel equipment, we can control the temperature to 0.1 degrees Celsius, which means that the reaction totally controlled and prevent "hot spots". Similarly, quality improvements in the distribution of heat and mass transfer process. Even in April of 2004 was such a big company Velocys, Dow Chemical and leading laboratories, the Pacific Northwest National Laboratory will apply in the production of ethylene and other olefins compounds.

Velocys now is developing microchannel technology for hydrogen production through the formation of steam from natural gas (methane). These reactors produce syngas - a mixture of carbon monoxide and hydrogen. Hydrogen production can be maximized through the "water gas shift reaction", ie the reaction of CO with water vapor at lower temperatures. Vapor formation process is endothermic requiring heat. Velocys utilizing heat from the combustion of methane occurs and excess hydrogen formed in the process of formation of steam. Endothermic or exothermic process and then combined. Each micro channel forming steam in the reactor is passed to the flow of hot combustion gases. Residence time in the reactor which caused a brief reaction temperature on the formation of steam and rapid cooling of the product. Heating and rapid cooling is required in this process in order to prevent the formation of carbon.

The combination of a compact between the formation of steam and combustion can quickly reach equilibrium at high temperatures and pressures. Secondly it shows achievement kedapat heat flux and rapid kinetics in microchannel reactors. Residence time can be reduced to 10 milliseconds - compared with a conventional reactor which takes 10 seconds. As a result, the volume of the entire system can be greatly reduced for the sake of efficiency.

Other studies utilizing microchannel reactors such as the production of methanol from syngas, the process of transforming natural gas into liquid hydrocarbons, and hydrogen peroxide production. Everything related to the processes that produce or require high temperatures. Latest technology that may be involved is the use of integrated nano catalysts in micro channels. In fact, small is not necessarily weak, because the gangs are small will also be strong even better than great, the challenge for the engineers in Indonesian.

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