Specifications

OPERATION MANUAL
“customer” – LSG60 Freeze Drier – “contract ref”
3.
OVERVIEW
3.1 General Description
The LSG60 Freeze Dryer is for the purpose of drying a wide range of approximately 150
aqueous products in a variety of different sizes of vials.
Freeze drying is a method used to dehydrate materials via a process involving the
sublimation of any water content (in the form of ice) under vacuum conditions. The process
can be subdivided into three (3) stages; freezing, primary drying, where the bulk of the water
content is removed by sublimation, and secondary drying where residual bound water is
removed at higher temperatures. LYOSCIENCE freeze dryers are capable of automatically
performing all these functions in a controlled and reproducible manner.
The equipment consists of a large vacuum drying chamber mounted alongside a refrigerated
condenser with integral vacuum pump. The drying chamber contains nine (9) refrigerated
shelves that can be moved up and down via an hydraulically operated ram for stoppering
processes. Both condenser and drying chambers are fitted with their own refrigeration
systems, with the capability of switching the condenser refrigeration duty to the drying
chamber. The temperature of the product shelves can be controlled between +60
o
C and –
60
o
C.
The condenser unit consist of a cylindrical chamber (290 X 860 mm) with a 160 mm
(ISO160) inlet port situated near the front of the chamber and a 40 mm (NW40)
outlet port positioned at the rear of the chamber. The chamber condensing coil is
cooled directly by an integral CFC free refrigeration system mounted in the base of
the unit. During freeze drying, water vapour that is extracted from the product, is
condensed onto the coil, resulting in the formation ice. The chamber has a total ice
capacity of ~15Kg between defrost cycles. The minimum temperature of the
chamber wall under vacuum conditions with no load applied is –80
o
C.
The condenser inlet is connected to the drying chamber via an electrically actuated
high vacuum butterfly valve. The chamber outlet is connected to the inlet of an
E2M28 vacuum pump. A transparent Perspex cover at the front of the condenser
allows the operator to inspect the ice build up and provides convenient access for
cleaning purposes.
The condenser chamber has a hot water defrost utility. An automatic defrost can be
incorporated into the Freeze Drying cycle.
An Edwards two stage oil-sealed rotary E2M28 vacuum pump is used to evacuate
both condenser and drying chambers. The pump outlet is fitted with a mist filter to
prevent oil mist escaping to the atmosphere. The exhaust of the filter is piped to a
stub connection at the rear of the freeze dryer, which in turn should be connected to
the end user’s exhaust extraction system.
Section 3 Issue: 1 Page 12 of 42