High Containment Transfer Systems

The need for high containment is greater than ever, given the increasing potency of processing ingredients and API’s.

Improving containment is often the main driver for specifying new process equipment in the pharmaceutical and associated industries. Current expectations of levels of containment often far exceed the capabilities of equipment designed and manufactured only a few years ago. There are many ways of improving process containment.

There are a number of reliable high integrity methods for ensuring high containment during transfer, some of these are explained below.

Gravity Transfer using a Hoist

Gravity Transfer typically uses a combination of gravity feed and flexible silicone sealing interfaces. Lift systems are often a main component in gravity transfer for accurate docking of process equipment such as IBC’s and valves.

High containment lift systems use intelligent positioning sensors to ensure outlets and inlets are precisely aligned, allowing the fast and accurate transfer of powders, granules and liquids etc.

‘Failsafe’ is another important feature of a lift system which is to be used in a high containment application. The security offered by the ‘failsafe’ feature ensures that even in the event of a machine breakdown, the two ports will remained docked, and most importantly, the material will remain contained and uncontaminated.

Flexible Silicone Connections

The connections between each element of the transfer process are the weakest links in the transfer chain. To ensure containment is not compromised at these connecting points, silicone dust caps and flexible sleeves can often be used. These elements provide simple cost effective containment which is very adaptable and easily cleaned.

Another benefit is that some of these components can be translucent of clear, allowing a visual indication of the process condition. Typically these transfer connections take the form of silicone caps and sleeves. Generally the connection parts are moulded in standard sizes so this should be taken into consideration when designing and specify new process equipment installations.

Split Butterfly Valves

The integration of a split butterfly or ‘High Containment Valve’ between the inlet and outlet of two process components creates a fully contained method of product transfer, with virtually zero exposure to either the operator or the process environment. This is extremely important when handling potentially hazardous material or material that cannot be exposed to ambient air.

Total sealing during emptying and filling operations can be easily achieved with the split valve system and fully automated valves can be specified which allow ease of operation in difficult to access locations such as containment isolators.

The split valve system comprises of an ‘active’ and ‘passive’ half. The active half of the valve has most of the moving parts and is usually static. The passive half is often installed on the moving part of the valve interface any in some cases a large number of passive valves and be docked into the same active half. The split butterfly valve provides the most effective high integrity method of contained transfer.

High Containment Vacuum Transfer

Another commonly used method of containment is vacuum or ‘pneumatic’ transfer, which uses contained pipe-work and hoppers to transfer material.

The main advantages of vacuum conveying are that it is very flexible if needed to cope with a variety of process duties, has very few moving parts and is easily cleaned.

The most common form of vacuum transfer is termed as ‘lean-phase’. The lean-phase method of vacuum transfer uses entrained air to create an air-flow for efficient material conveying.

Vacuum transfer can be used over considerably long distances and has the additional benefit of being very low maintenance. Conveying of materials by vacuum is a well established process in the pharmaceutical industry and rarely has any detrimental effect on the product integrity.

There are many different configurations used in vacuum conveying allowing automated material pick-up, level control, multiple integrated systems and other special design to deal with variable material properties.