Stainless steel plant systems for research, scale-up and production on a small and medium scale for processes with high sterile requirements



PROREACT P laboratory and pilot fermenters are designed for processes with very high sterile requirements. Standard sizes from 10 – 1.500 L are available. They are used for research and development as well as preliminary stages within a production fermenter cascade of increasing size (see PROREACT P Production Bioreactors and PROREACT «seed train»).

For this reason the plants are designed similar to the industrial plants themselves, so that the same philosophy can be found in the area of process control, automation structure and maintenance as in production processes.

The PROREACT P fermenters for research purposes are configured much more flexible

This concerns the interchangeability of different agitators, different process strategies and the connection of various additional sensors or modules for upstream and downstream processing. As special applications, smaller fermentation units can also be integrated into a plant.

Via a number of open communication interfaces, the plants can be connected to data evaluation programs, laboratory management programs or even complex SCADA systems.

A basic unit consists of the following plant components:

  • Pressure vessel -1 to 6 bar (optionally higher pressures) with double jacket made of stainless steel 1.4404/1.4435
  • Surfaces in contact with product with Ra ≤ 0.8 μm (optional Ra ≤ 0.4 μm with electropolishing)
  • Mixing and gassing unit with various selectable agitators
  • Thermosiphon unit for mechanical seals
  • Piping and fittings in DIN 11864
  • Automatic diaphragm valves in the product area
  • Integrated peristaltic pumps for substrates, adjusting agents and antifoam agents
  • Compact frame to hold all pipes and aggregates
  • Sterile filter units for supply and exhaust air
  • Air volume control
  • Sterilizable sampling valve
  • SIP connection with condensate lines
  • CIP connection with valve technology for automatic cleaning
  • Bioreactor sensors and sensors for peripheral units
  • Central control unit with SIEMENS SPS and touch panel

Individual PROREACT laboratory/pilot fermenters can be combined with the production fermenters for a production line over several cultivation stages (e.g. 20 L, 200 L, 2,000 L, 20,000 L) to form a complete stage structure.

Frings considers the customer-specific requirements and qualification standards

It is also possible to adapt the entire architecture to automation. The SIEMENS industrial control systems used as a platform for this purpose allow for a variety of possibilities, which we would be happy to use for you in a demand-oriented manner.

For the development and production of biopharmaceutical or medical fermentation products, the systems are also supplied with the corresponding GMP documentation. For these plants of the PROREACT G series, special attention is paid to customer-specific qualification standards.

The document management is closely based on the customer’s own specifications and of course the systems are also realized with the customer’s respective components and design specifications.

The same applies to all PROREACT products. If you, as a customer, have special factory standards or construction specifications, we are happy to integrate these requirements already in our basic engineering and build you your customized system.


The PROREACT P basic units can be equipped with a variety of different standard modules, so that the handling of the plants can be simplified and the range of possible bioprocessing techniques can be extended significantly.

  • Sterile connections such as sterile crosses and sterile quick couplings
  • Weighing device for fermenters
  • Gravimetric flow controllers for feeds
  • Gas mixing station with mass flow controllers
  • Exhaust air cooler/heater
  • Integrated CIP pump with CIP circuit
  • Built-in steam generator for SIP
  • Sterilizable media and storage tanks
  • FOAMEX foam centrifuges
  • FRIBORATOR high performance aeration turbines
  • Exhaust gas analyzers for O2, CO2 or various special gases
  • Advanced sensor technology (e.g. ALCOSENS)
  • Lid lifting device
  • Media filtration
  • In-situ processing techniques (e.g. cross-flow filtration)

To minimize or completely avoid the use of antifoam agents, the installation of the optionally available FOAMEX foam centrifuge is recommended. The ALCOSENS measuring probe allows extended process documentation for fermentations with alcohol as substrate or metabolite. In addition, control strategies for methylotrophic yeasts are easily possible with it.


  • PROREACT P: Bioreactors for sterile technical processes in biotechnology
  • PROREACT B: Bioreactors for hygienic processes especially in brewery, baker’s yeast and beverage applications
  • PROREACT G: Bioreactors with equipment and documentation according to GMP pharmaceutical standards
  • PROREACT C: Bioreactors without sterile or hygienic design according to chemical standards (for auto sterile processes)


In addition to the configuration of bioreactors from standard construction kits and modules, Frings can also implement completely customized solutions.

Especially novel processes from development often require bioreactor designs that deviate from the usual standards.

One of Frings’ core competences is to realize designs and bioreactor equipment adapted and optimized to the bioprocess.

For this purpose we use appropriate design tools and are also able to carry out experimental investigations in the company’s own laboratory and pilot plant in order to find the ideal technical solution.

In the past we have already realized various projects with customers and are particularly qualified in the segments:

  • Construction, acceptance and documentation of ATEX-compliant bioreactors (both laboratory and pilot as well as production scale)
  • Optimization of the gas input rate through high-pressure reactors and the use of high-performance gassing turbines
  • Use of special materials such as Hastelloy, Superduplex or plastic-coated materials for corrosive fermentation media
  • Integrated product separation and/or cell recirculation by using internal and external subsystems (e.g. membrane filtration)
  • Continuous and semi-continuous process control of bioprocesses


Tel.: +49 (0)22 26 89 29 – 400



Boschstraße 32 53359 Rheinbach
Tel.: +49 (0)22 26 89 29 – 400 Fax: +49 (0)22 26 89 29 – 401