Biotech Removable Sparger Designs0 pages

Quick Change Sparger System
for Bioreactors and Fermentors
Sparging and Mass Transfer from Gases to Liquids
In bioreactor and fermentor systems, optimal mass transfer of gases like
oxygen or carbon dioxide is perhaps the most difficult task to accomplish.
Oxygen, in particular, is poorly soluble in water - and even less in cell culture
and fermentation broths. Oxygen transfer is aided by agitation used to mix
nutrients and to keep the cell culture or fermentation homogeneous. There
are limits to agitation speed due to high power consumption as well as
damage to organisms resulting from excessive tip speed. Agitation alone
does not provide adequate mass transfer.
Using a Mott porous metal sparger greatly increases mass transfer rates in
bioreactors and fermentors. The introduction of gases into stirred or unstirred
reactor vessels via millions of tiny bubbles increases the gas-to-liquid contact
areas allowing for optimal mass transfer rates. In-tank applications, with
sparging elements located inside the tank, can be batch or continuous flow,
with or without agitation.

Quick Change Spargers* Provide Fast and Easy
Installation and Validation
In the past Mott porous metal sparger elements, or “frits” as they are
sometimes called, were welded to the end of sparger assemblies. This
fixed method of attachment required either a cut and re-weld method of
replacement or a clean out-of-place method for the entire sparger assembly to meet GMP validation methods.
Today, Mott offers a Quick Change Sparger that reduces the time and effort to
replace the porous metal sparger element.
figure 1 Mott porous metal sparging
With the Quick Change Sparger system (see figure 2), the porous metal element
elements with sparger wand and quick
can be removed and replaced after each use. Eliminating the need to re-weld
change trident adapter
the tip or clean the entire assembly. After each batch, a new tip can be installed
on the end of the assembly and is ready for steam in place operation. Or the
sparger tip can be cleaned out of place utilizing a number of methods including ultrasonic cleaning or detergent and water flush.
Either way, the Quick Change Sparger can help make sparger change out simple and easy. Changing to new clean sparger tips after
each batch provides an excellent method of maintaining GMP process validation methods.

Available for Retrofit
The Quick Change Sparger consists of a trident adapter
for the end of the sparging wand or assembly and a mating
porous metal sparging tip (See figure 4). The adapter can
be used to modify existing sparger assemblies to accept the
Quick Change Sparger tip. The trident adapter design provides
optimal support for the porous element without the need for
threads, clamps or other excessive areas that cannot be
sterilized during SIP cycles.

Mott Porous Metal Spargers –
a Biotech Industry Standard
The ultimate goal of the bioprocess engineer is to provide
an optimum environment for biological processes. One major
concern is the shear sensitivity of certain cell cultures. The
use of shear protective additives such as Pluronic F-68 or
methyl-celluse are proven to reduce the shear impact of bubble
rupture from sparged gas in cell cultures. Industry studies have
continually proven that the simplest and most effective method
of oxygen transfer is direct sparging of gas into the system.

figure 2

For decades bioreactor and fermentor designers and operators
have relied on Mott porous metal spargers to provide this uniform
bubble size and dispersion rate. The 316L SS porous metal
spargers are robust and capable of withstanding temperatures in
excess of 400°C (752°F) and differential pressure in excess of
500 psid. This rugged material allows for repeated sterilizations
via autoclave or through steam in place methods. The 316L SS
material also ensures zero out-gassing and no extraction of
harmful contaminants.
* Patent Pending