Pilot and Process Scale SFE

The basic process of extraction on a process scale is analogous to that on a laboratory scale and is shown schematically in Figure 2. The fluid substance, such as carbon dioxide, is pumped as a liquid and therefore is initially cooled to, say, 5°C, which must allow for some heating during pumping, and kept in a cooled reservoir. A system for adding a proportion of liquid modifier, not shown, may be incorporated. The fluid is then heated to the extraction temperature and pumped into an extraction cell, which is maintained at this temperature. The matrix to be extracted is packed into the extraction cell in a mesh basket to prevent it being carried out of the cell during extraction. Following extraction, the pressure is reduced to precipitate the extract through a control valve. The flow rate of fluid is controlled by the rate of pumping and the pressure in the extraction cell is controlled by the setting of the control valve for a particular pumping rate. Control systems may be used to control the extraction conditions. Reduction of pressure causes cooling of the fluid and so heat input is required, as shown. The precipitated material is collected at the base of the collection vessel, which has temperature control and also pressure control from the control valve on the fluid exit. A series of collection vessels at successively lower pressures may be employed to trap all the extract and separate it into fractions to some extent. A trapping liquid, such as a vegetable oil, may be used on a process scale to give a particular product. Trapping onto a surface, such as active charcoal, may also be used, particularly for volatile products, followed by thermal desorption. On a process scale the fluid leaving the collection vessel is likely to be cooled for recycling.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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