VHE Economizer for deodorization and physical refining of fats and oils - Alfa Laval - #1

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Application This high-performance heat exchanger is specially designed to recover heat by cooling the deodorized edible fats and oils in deodorization and physical refining plants and – at the same time – heating the incoming oil. This cooling takes place under vacuum and sparging steam conditions. The VHE Economizer is part of the Alfa Laval SoftColumn™ deodorization concept, but is also available as a retrofit component for installation in other deodorization systems – irrespective of origin. Operating principles The hot deodorized oil enters the VHE Economizer at one end of the shell side, which is under vacuum, and flows through a special system of channels and baffles until it reaches the outlet connection at the other end. It is then pumped out for final cooling and storage. A level transmitter installed on the shell controls the oil level on the shell side. The cold oil enters the VHE Economizer under pressure on the tube side and flows through a multipass tube system until it reaches the outlet connection at the other end. The sparge steam is injected through perforated tubes located on the bottom of the shell, below the heating tubes. Counter-current flow between the incoming oil and deodorized oil is maintained by a special design of the tubes and baffles on the shell side. To avoid cross-contamination and provide fast draining during stock changes, the heat exchanger is fitted with a special fast-drain valve arrangement on both sides. Design features The VHE Economizer is designed to achieve a high level of heat recovery by cooling the deodorized oil under vacuum and sparge steam conditions, while heating the incoming oil. Under full sparge steam conditions, this gradual cooling means the oil is treated gently and the quality improves. The sparge steam also acts as stripping to remove volatiles that might form during the cooling phase, and to improve the heat transfer rate. The large heat transfer surface area and the counter-current flow result in a very high oil-to-oil heat transfer rate, which normally means a heat recovery exceeding 75%, depending on the size, application and operating parameters. The low liquid level and channel system with baffles ensure that the oil follows the desired path. The first oil that enters is The VHE Economizer For deodorization and physical refining of fats and oils VHE Economizer