2020 REFINING PROCESSES HANDBOOK PROCESS CATEGORIES COMPANY INDEX LUBRICANTS AND WAXES Solvent Lube Dewaxing Application: A process to produce dewaxed oils and slack waxes. Description: Light, medium and heavy cuts are chilled at carefully controlled rates. Solvent (e.g., a mixture of MEK and toluene) is added incrementally in the chilling train. Filtration is carried out in two stages. The wax from the "primary" filters contains substantial amounts of dewaxed oil. This "wax" is re-slurried with additional cold solvent, re-filtered and washed in the second stage, the "re-pulp" filter. Filtrate from the primary filter is sent to the solvent recovery section, while the filtrate from the secondary filter is used as solvent in the tile incremental dilution system. The solvent recovery is carried out in three stages for energy-efficient operation. Chiller Secondary filters Water settler and surge tank Solvent fractionator Wax mix flash section Refrig. STM Refrig. Feeds: Solvent refined lube stocks or raw stocks of any viscosity and density. Main filtrate Products: Dewaxed oils with specified pour points. Slack waxes with oil contents of 5%-10%. In the case of a combined dewaxing/de-oiling plant, de-oiled waxes with less than 1% oil or with specified penetration values could be produced by adding a third filter stage. Utilities: (Typical, Middle East crude; units per m³ of feed): Electricity 100 kWh LP steam 230 kg Cooling water 50 m³ Fuel energy 400 kWh Primary filters STM Slack wax Sewer Repulp filtrate STM DWO mix Dewaxed oil Raffinate Exchanger Solvent receiver DWO flash towers DWO stripper Installations: Numerous installations under thyssenkrupp license are in operation around the world. Licensor: thyssenkrupp. The former proprietor of this technology was ThyssenKrupp Uhde GmbH. Website: www.thyssenkrupp-industrial-solutions.com Contacts: sandra.jensen@thyssenkrupp.com, dorothe.weimer@thyssenkrupp.com Copyright © 2020 Gulf Energy Information. All rights reserved.http://www.hydrocarbonprocessing.com/ http://www.thyssenkrupp-industrial-solutions.com