After the batch has been distilled, the contaminants remain in the boiler and are removed. The container for the dirty solvent may be either fixed or removable. A plastic liner, suitable for high temperatures, may be used with a fixed container to facilitate clean-up. These liners are normally found in the smaller sizes of equipment. 3.4 Most recovery equipment operates at or near atmospheric pressure, but some equipment has a vacuum system to lower the pressure in the dirty solvent container.
Lower pressure results in lower solvent boiling points and so allows a lower operating temperature.
Return to index 4. 4.2 Explosion venting to the outdoors must be provided for the room or building to prevent critical structural and mechanical damage from an internal explosion. Pressure-resisting walls and roofs should be designed to withstand explosion pressures of at least five times the relieving pressure of the explosion vents without collapse. Return to index 5. Return to index 6.