214 K.K. Rajah Bogota in 1969. Subsequently other plants were installed world-wide to fractionate a ariety of oils including milk fat, lard, hardened(hydrogenated)soyabean and fish oils Yields of oleins are typically in the range 67-72%, and Deffense(1991)has suggested a further 8% increase is achievable if a membrane filter is used The florentine filter can be used to separate high levels of solids, up to the 60-70% range if required vacuband batch filter The Miller Vacuband filter(Miller, 1980; Kehse, 1979)which is a stationary bed vacuum lter(see Fig 8.5; Rajah, 1988), was used in semi-commercial scale production of milk fat fractions system, offered by CJC (Oakmere, Cheshire, UK), shows important advantages over the ' open vacuum systems Fiiter Pressure (stearin) pper chambe Filtrate chamber pump Fig. 8.5. Vacuband filter arrangement(Miller Filter Company Ltd, Overath, Germany and Chris James Consultants, Oakmere, Cheshire, UK) Crystallisation of milk fat was carried out in a jacketed stainless steel vessel of virtually identical design to that of a batch stirred tank reactor(BStR) Nominal working capacity of the vessel was approximately 400 kg charge of anhydrous milk fat(AMF feedstock. To achieve good heat transfer characteristics, the vessel was fitted with a variable speed, full sweep, anchor-type agitator arranged to prohibit mass rotation. Agita tor speeds were possible within the range 4-30 r.p. m. although the optimum range was found to be 7-10 r.p. m, i.e. 0.36-0.52 m s". The vessel was additionally rated at 3. 3 bar, for positive pressure nitrogen blanketing of product. During crystallisation, the head space was purged to establish a nitrogen blanket. The temperature difference between the oil and water jacket was maintained at a maximum of 5C. Separation of milk fat was carried out on the novel, stationary-bed, vacuum band filter, the Vacuband, surface area l m, Fig. 8.5. The novelty lies in being able to filter and separate the liquid from the solid phase, under vacuum, within an enclosed upper chamber. This solid-liquid separation system is being used in a variety of liquid processing industries and in the edible oil industry during bleaching earth filtration, winterisation, and hydrogenation catalyst filtration. The unit comprised an indexing, horizontal rolled stored filter medium paper), arranged over a static lower vacuum chamber and with a second upper movable (vertically) vacuum/feed chamber in opposition. The standard design utilised the upper214 K. K. Rajah Bogota in 1969. Subsequently other plants were installed world-wide to fractionate a variety of oils including milk fat, lard, hardened (hydrogenated) soyabean and fish oils. Yields of oleins are typically in the range 67-72%, and Deffense (1991) has suggested a further 8% increase is achievable if a membrane filter is used. The Florentine filter can be used to separate high levels of solids, up to the 60-70% range if required. Vacuband batch filter The Miller Vacuband filter (Miller, 1980; Kehse, 1979) which is a stationary bed vacuum filter (see Fig. 8.5; Rajah, 1988), was used in semi-commercial scale production of milk fat fractions. This system, offered by CJC (Oakmere, Cheshire, UK), shows important advantages over the ‘open’ vacuum systems. Fat slurry crystal - Vacuum Pump Fig. 8.5. Vacuband filter arrangement (Miller Filter Company Ltd, Overath, Germany and Chris James Consultants, Oakmere, Cheshire, UK). Crystallisation of milk fat was carried out in a jacketed stainless steel vessel of virtually identical design to that of a batch stirred tank reactor (BSTR). Nominal working capacity of the vessel was approximately 400 kg charge of anhydrous milk fat (AMF) feedstock. To achieve good heat transfer characteristics, the vessel was fitted with a variable speed, full sweep, anchor-type agitator arranged to prohibit mass rotation. Agita￾tor speeds were possible within the range 4-30 r.p.m. although the optimum range was found to be 7-10 r.p.m., i.e. 0.36-0.52 m s-’. The vessel was additionally rated at 3.3 bar, for positive pressure nitrogen blanketing of product. During crystallisation, the head space was purged to establish a nitrogen blanket. The temperature difference between the oil and water jacket was maintained at a maximum of 5°C. Separation of milk fat crystals was carried out on the novel, stationary-bed, vacuum band filter, the Vacuband, surface area 1 m2, Fig. 8.5. The novelty lies in being able to filter and separate the liquid from the solid phase, under vacuum, within an enclosed upper chamber. This solid-liquid separation system is being used in a variety of liquid processing industries and in the edible oil industry during bleaching earth filtration, winterisation, and hydrogenation catalyst filtration. The unit comprised an indexing, horizontal rolled stored filter medium (paper), arranged over a static lower vacuum chamber and with a second upper movable (vertically) vacuum/feed chamber in opposition. The standard design utilised the upper