Moving experience

A vacuum transfer system capable of handling 3,000kg/hr has been installed by Pneumatic Conveying Systems (PCS), of Stockport in the UK, at Norgine's factory at Hengoed, South Wales.

Since it came into operation, the new system has increased efficiency and improved operator wellbeing by reducing both manual handling and atmospheric dust.

Norgine specialises in gastroenterology, and its Hengoed facility manufactures a wide range of products, including therapies for manic depression, faecal impaction, irritable bowel syndrome and constipation.

The PCS system was installed as part of an upgrade of the plant dedicated to the production of Movicol - a laxative used in the oncology, neurology and pain treatment departments of hospitals. Movicol is a product of Norgine's own development, clinical research and pan-European registration. Launched approximately five years ago, the drug accounts for around 40% of the company's total sales.

increased capacity

The key reasons for upgrading the Movicol plant were to increase capacity to meet future demand predictions, to remove ergonomic issues associated with the manual system and to improve cGMP compliance. The project was undertaken as part of a site upgrade designed to ensure that both MHRA and FDA requirements are met, the latter to enable the product to be marketed in the US.

Dublin-based consultancy Project Management was employed to undertake a feasibility study relating to the use of a bulk transfer system for polyethylene glycol (PEG), Movicol's main ingredient. After product trials and a technical bid analysis on the tenders submitted, PCS emerged as the recommended supplier.

Polyethylene glycol powder has a fragile crystalline structure than needs to remain intact, so the product has to be transferred with little and preferably no degradation. Norgine personnel performed trials at PCS's comprehensive test centre to satisfy themselves that the proposed vacuum transfer system would not have any detrimental effects on the substance.

The trials involved longer conveying distances than for the present layout in which the PEG sacks are opened local to the mixer. The factory refurbishment programme is currently underway, and once it is completed, it is planned that PEG will be transferred directly from one tonne FIBCs in the warehouse via the vacuum conveying system to the mixer.

The decision to award the contract to PCS was made after the successful completion of these further trials at full-scale production rates. PCS supplied, installed and commissioned the system.

The exhauster (vacuum pump) is skid mounted and located separately in a remote plant room. A vacuum line runs from the exhauster through the wall of the Movicol production area terminating in a wall plate. From here a flexible connector runs to the vacuum hopper above the mixer. The exhauster is sized to handle the longer conveying lines that are planned as part of the future development of the site and which will be used when the FIBC discharger is up and running in the new warehouse extension.

Movicol is based on PEG, which is compounded with a variety of salts, flavourings and sweeteners. Typically 12 batches are mixed every day over three shifts. Each batch consists of a number of bags of PEG which are discharged into a sack tip unit. Product is immediately transferred through the PCS vacuum conveyor to a twin paddle mixer.

Any airborne 'dust' caused by opening the bag is either drawn into the product flow or extracted away from within the sack tip hood, resulting in a very clean and safe sack tipping operation.

in-line sifting

En route to the mixer, the polyethylene glycol passes through an in-line flat deck sifter that removes any agglomerates which have formed during storage and any extraneous packaging material released during bag slitting.

With the PEG in the mixer, pre-weighed minor ingredients are added and then, after mixing, the contents are discharged into an IBC located on the floor below the mixing level. The IBC is then removed and tumbled to produce a homogenous mix ready for packing.

The PCS conveying system is designed to be easily stripped down for thorough internal cleaning. 'Our operatives are very happy with the system. It has improved our working environment and it is very easy to clean,' said team leader Dilwyn Simmons.