Rectification continuous

Film evaporators with rectification are used for gentle partial evaporation of liquid mixtures whose high-boiling fraction has components with boiling points close to those of the distillate to be separated. The rectification column achieves a depletion of these components from the distillate and vice versa of the low boiling point from the concentrate and thus purer distillate and concentrate fractions.

Often these processes have to be carried out at low operating pressures, for example to enable gentler temperature conditions for high boilers, and require the advantages of film evaporator systems. The falling film evaporator based system ERF is preferably used for larger feed quantities and the thin film evaporator system ERT for short residence times and further enrichment in the sump area.

The raw solution is fed into the evaporator or column and evenly distributed as a thin film over the surface of the evaporator tubes or column packing using a special distribution system. From the liquid stream flowing into the vaporizer, the light boilers are partially evaporated and fed into the column where vapor and liquid are in countercurrent contact and a high separation efficiency is achieved by built-in components.

The distillate depleted of secondary components is liquefied in the condenser E03 and, after recirculation of the required quantity of reflux, is either collected as distillate in a receiver tank or continuously discharged via a pump P03. Similarly, the concentrate is discharged from the evaporator using pump P02.

Vacuum pumps are used to set the desired process conditions (pressure & temperature).Thermostats (laboratory and pilot scale) and classical energy sources (production scale) are used for heating, evaporation and condensation. A cold trap is used to reduce undesired entry of low boilers from the exhaust gas flow into the vacuum pump.

Depending on the application and process requirements, further units such as an exhaust gas scrubber or short film evaporator can also be connected downstream in a modular fashion.

• Combined evaporation and rectification systems with low hold-up and gentle operating conditions for
  • Laboratory and pilot systems made of stainless steel and borosilicate glass 3.3 in standardized design, optional process-specific adaptations
  • Production systems made of stainless steel in process- and customer-specific design
• Modular supplementary evaporator systems according to process requirements, e.g.
  • Upstream and downstream evaporators, e.g. system EFF-ETF, or Flash-Box
  • Rectification column for concentration of vapours, system ETR
• Process and customer-specific guidelines, e.g. ATEX, DGRL, FDA, GAMP, ASME, UL standards.
• Suitable for media with increased demands:
  • Mixtures with high boilers and components with close boiling points
  • Low-viscosity media
  • Heat-sensitive media
  • Larger feed volumes
• Existing expertise for typical applications or feasibility studies with tests and scale-up verification
  • Specialty and agrochemicals
  • Pharmaceuticals and cosmetics
  • Flavours and fragrances
  • Food / Additives
  • Fatty acids
  • Various other products of the fine chemicals and pharmaceuticals sector

For many applications, in addition to the composition of distillate and/or residue or concentrate, product properties such as odour and colour are also relevant. Likewise, possible effects that may occur during evaporation, such as foaming or fouling on the heat transfer surface, must be taken into account. The latter cannot be determined or estimated theoretically, but require a visual evaluation of the evaporation process. This can best be implemented in glass plants from COROSYS, which can be individually assembled in a modular system.

Once the general feasibility has been established, the process parameters for the design of a production plant shall be verified, i.e. heat transfer and maximum area-related evaporation rates or practical number of stages as well as the achievable yields and qualities shall be determined. For this purpose, COROSYS has a standardized series of pilot plants made of stainless steel (optionally also special materials) in various sizes and designs to choose from.

For new evaporation or distillation tasks, COROSYS offers in-house services ranging from literature research, thermodynamic simulations and laboratory tests to piloting of single systems or combinations of falling film (EFF), thin film (ETF) and short path evaporators (ESF), if necessary also in combination with rectification (ERF).

The main objectives and possibilities of preliminary studies/test distillations as well as laboratory and pilot plants are again briefly and clearly summarized in the following table: