Patent RU-2708577-C1 (RU)
Title: Method of producing paraffin heat accumulating materials and device for its implementation
Inventor: Vishnevskii Anatolii Viktorovich
IPC: C07C9/15
Filed: 2019-04-15
Granted: 2019-12-09
Abstract: FIELD: technological processes. 
     SUBSTANCE: invention relates to a method and device for producing paraffin heat-accumulating materials (PHAM) from petroleum and synthetic paraffins, capable of absorbing heat energy by switching from one phase state to another and separating it at reverse transition. Method of producing paraffin heat accumulating materials consists of the following steps. Paraffin C 14 -C 17  is heated on the vacuum fractionation unit in heat exchanger, and then heated in furnace. Paraffin C 14 -C 17  is fed into a first distillation column, equipped with stripping, vacuum generating system and refrigerator, note here that water vapor is fed into bottom part of first rectification column and stripping. Off-site n-alkane fraction C 14 -C 15  is removed from upper part of first distillation column and non-target n-alkane fraction C 17  from lower part of first rectification column in form of residue. Target wide n-alkane fraction C 16  is isolated in stripping   and first supplied for heating into furnace, and then, as raw material, into second rectification column, in the lower part of which steam is added, which is equipped with a vacuum generating system and a cooler. Wide n-alkane fraction is separated into two narrower by n-alkane composition fractions of rectificate and residue in second rectification column. Fractions of rectificate and residue obtained on a vacuum fractionation unit are successively processed on an adsorption purification unit. After successive processing on the adsorption treatment unit, the obtained purified and stable n-alkane fractions of the rectificate and the residue are fed for processing to a crystallization fractionation unit. On crystallization fractionation unit fraction of rectificate or residual fraction is heated for 4–6 °C is higher than turbidity temperature and loaded into crystallizer. At the end of the crystallization process, the formed suspension is supplied by the pump to the membrane filter press at constant temperature and slow stirring. As a result of filtering the suspension, a paraffin wax is obtained, dried with a downward flow of inert gas and compressed by a filter press membrane. Value of inert gas temperature is within ±1 °C as compared to the temperature of the flat cake. After drying with inert gas and compression of paraffin flat cake with membrane filter press, compressed cake is discharged into heated container, where it is melted. Then the melt of the liquid flat cake and the filtrate obtained earlier on the filter-press are pumped out into the appropriate reservoirs of the commercial product park. Device for producing paraffin heat-accumulating materials comprises cylindrical housing with upper and lower bottom-cover, feed inlet fittings, inert gas feed and suspension output. Inside the casing there are two coaxially rotating agitators. One agitator is made with plate elements for radial mixing. Second mixer is made with blades for axial mixing. Housing has an external cooling jacket with a lower coolant feed union and an upper coolant discharge union. 
     EFFECT: invention enables to obtain paraffin heat-accumulating materials with narrower fractional (n-alkane) composition, improved operational characteristics, increased heat accumulating capacity of paraffin heat accumulating materials, increased filtration rate and clarity of separation of suspension into solid and liquid phases, prevention of thickening of suspension at its unloading, excluding wear, deformations and breaks of plate elements, reducing operating and capital costs, reducing power consumption during production, improving operational reliability and repairability. 
     8 cl, 5 dwg, 2 ex