Defeng opts for Praxair cooling technology

The cooling system is necessary for Defeng to manufacture a new active pharmaceutical ingredient (API) that has to be kept below -30°C in a large volume reactor.

To achieve this goal Defeng has obtained technology for cooling its plant from Praxair, which is supplying its NCOOL system for the task.

The NCOOL technology Defeng has licensed uses nitrogen to remove the heat from the reactor via a heat exchanger.

Praxair claims this system " provides more rapid response and closer approach temperatures without the risk of freezing ."

By utilising nitrogen instead of mechanical refrigeration Praxair's system minimises the need for moving parts and does not use ozone-depleting halogenated coolants.

David Chow, president of Praxair China, said: " This new application of the NCOOL technology opens up another segment of the fast growing cryogenic refrigeration market in the pharmaceutical industry ."

Although Defeng only needs its reactors to be cooled to -30°C the NCOOL technology can potentially chill a system to as low as -140°C, providing versatility for users.

Praxair's NCOOL technology, which the company extols as a highly efficient and effective system, potentially puts it in a strong position to exploit the growing demand for cryogenic refrigeration.

In addition to NCOOL , which is an indirect cooling system.

Praxair's portfolio includes DCOOL that offers direct cooling.

This system injects liquid nitrogen directly into the reactants to give the " fast response and precise temperature control required for fine chemical applications ".

Through use of its proprietary injector in the DCOOL system Praxair believes it has eliminated the risk of freezing.

By offering the NCOOL and DCOOL systems, as well as its range of cryogenic condensation and freezing equipment Praxair has created a portfolio spanning numerous aspects of the manufacturing process that require a cooling component.

The company's reach extends far beyond pharmaceutical cooling though, with a portfolio covering industrial gases used by the aerospace, chemicals and energy industries among others.

Sales in 2007 totaled $9.4bn.