In recent years biofuels have been the subject of a social and environmental dilemma. Large areas in developing countries have been cleared and used for sugar cane biofuel monocultures or similar, and these countries have unintentionally been brought into competition with food production.
This issue has inevitably led to the development of more climate-friendly and socially acceptable uses of second generation bio fuels. Only the oily contents of the infructescence of a plant were used for the first generation bio fuels, compared with second generation bio fuels, where only the cellulose, hemicellulose-containing parts of the plant; (mostly the leaves of the plant or the stem axes) were used.
This type of utilization has three significant advantages: firstly, the fuel does not compete with animal feed or food production, as the infructescence, for example a kernel of corn, can still be used for food production. Secondly, the plant parts containing cellulose are considered the energy-richer parts.
The production cost has to be considered as a third aspect. The plant parts containing only cellulose and hemicellulose, are clearly much more readily available from the raw materials market than those with a high degree of nutrients, for example lipids, proteins, and mono or disaccharides.
Bio Process Technology
Biocatalysis (fermentation) and bio process technology are used to produce bio ethanol. Usually, the lignocellulose containing residual material has to be prepared to run well-engineered bio process technology plants.
In this process, two elements play a part: the degree of the comminution (particle size) due to the installed technical components of the plant, like valves and the built-in control systems and measurement instrumentation, and, possibly more importantly, the product of the comminution high surface and the associated fermentation period and residence time in the bio-fermenter.
The microorganisms and enzymes used are given the opportunity to obtain the highest possible plant effectiveness in a time and resource-saving approach.
In many pilot plant stations and pilot installations FRITSCH Cutting Mills are utilized for the comminution of the residual plant matter. Here, the Universal Cutting Mill PULVERISETTE 19 is used in combination with the sample exhauster and the cyclone separator. Advantages of this system include effortless handling during cleaning and the exchange of the cutting tools.
PULVERISETTE 19 with Cyclone separator
Easiest exchange of cutting tools
Achieving ultimate fineness is considered to be important in the production of bio ethanol. Sufficiently large amounts of bio mass can be produced with a particle size distribution from amounts smaller than 250 µm, because of the utilized patented FRITSCH sample exhaustion, and these amounts can then be transferred to the fermentation plants without any problems.
The attainment of the required degree of final finenesses depends mainly on the regulating factors of the machines (sieve inserts/comminution principle) and also on the type of commodities. So, inevitably the available sieve passage surface with the used 100 µm sieves are multiplied and reduced when compared to the standard sieves, leading to a high degree of physical strain on the sample material.
Usually, this physical strain becomes obvious through the generation of heat in the instrument, as well as a reduced throughput.
HEPA – fine dust filter, (High-Efficiency-Particulate-Filter for the Cutting Mill
The directed high volume air current of the cyclone of 2800 l/min will help avoid these problems. Additionally, dust exposure in the workplace is reduced by sample exhaustion due to the polyester pre-filter, which has a separation limit of 5 µm and a HEPA – fine dust filter (High-Efficiency-Particulate-Filter) with a separation limit of 0.3 µm.
This information has been sourced, reviewed and adapted from materials provided by FRITSCH GMBH - Milling and Sizing.
For more information on this source, please visit FRITSCH GMBH - Milling and Sizing.