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Background

Young & Co.'s Brewery had been considering automating the brewhouse at the Ram Brewery in Wandsworth, London, for some time but were uneasy due to previous bad experiences with process control contractors. Following discussions with Canongate during the latter part of 1999, David Gray, Chief Engineer at Young's, decided that, due to their unmatched experience in automation within the brewing industry, Canongate were the right company to work with.

Brewhouse Control Project

Canongate Technology Ltd. were awarded the contract to project manage, design, supply and commission a new control and SCADA system for controlling the mashing process and cleaning of the two conventional Mash Tuns at the brewery. Canongate Technology Ltd. also project managed, designed and commissioned the electrical work on-site. The electrical installation contract was awarded to Nala Engineers Ltd. and the Motor Control Centre contract awarded to Industrial Display Systems.

The mechanical design aspect of the project was designed and managed by Young's personnel, with the installation contract being awarded to Shobwood Engineering (Burton) Ltd.

Process design

As the brewing and cleaning processes were totally manual, a process control philosophy document was designed in conjunction with brewery personnel. A Functional Design Specification (FDS) for the project was then produced based on this agreed document. The FDS was used for all aspects of the control strategy. The manual equipment that was automated included routing valves, pumps, level probes, flowmeters, flow control valves etc.

Control System

The control system installed consists of an Allen Bradley SLC5/05 programmable controller with analogue and digital interface. As part of the project, three existing SLC503's running other operations within the brewery were upgraded to SLC5/05's. The SLC controls all the process from mashing in, wort run off, wort copper fill selection, mash tuns grains out, Cleaning In Place (CIP) and all liquor flushing.

Communications Network

The existing Allen-Bradley DH485 network was replaced with a Local Area Network (LAN) using Thin Ethernet IEEE802.3 10Base2 Coax in a bus topology. The SLC and SCADA nodes are directly connected to the network via Hubs and RJ45 patch cords.

SCADA

The SCADA system is Intellution Fix version 7.0 using Allen Bradley RSLinx to communicate with the SLC's. The operating platform is Microsoft Windows NT. The system is designed to give the brewer complete control of the mashing process from recipe menus. There are 20 standard named qualities available from which the brewer can select to alter brew details or accept the standard brew.

From the selected recipe, dry goods quantity, a liquor to grist ratio and total volume of wort to be collected and sparge volume to be used is calculated. The system also has parameters to calculate liquor plate cover volume, liquor underlet volume, stand times, delay to sparge and wort run off profile, including wort flow ramp ups, and copper fill volumes. The facility to alter parameters whilst a brew is in progress is also available to the brewer. The system also gives real time trends of the wort run off flowrate and sparge liquor flowrate profiles.

The Clean in Place (CIP) and liquor flushing of the Mash Tuns and wort mains is also controlled via SCADA selection. All functions are date and time stamped when last completed. As part of the overall project, modifications to the wort heat exchanger were also carried out, this included moving temperature control from panel mounted instruments to the SLC5/05 and the installation of wort oxygenation and measurement control system.

In order to ensure smooth on-site commissioning, Young's technical and operation staff spent three consecutive days at Canongate premises for simulation. During this time some minor changes were introduced. It was felt that with operators' input at this stage the system would be introduced seamlessly. With tight production schedules to meet, it was essential that all changeovers took place over a planned five day period with no production loss.

Conclusion

Following completion of the project in early April 2000, David Gray commented "the job progressed well with an excellent simulation. Canongate's understanding of our functional requirements was excellent as was the quality of hardware and software delivered. The commissioning was carried out very smoothly with minimal disruption. Altogether an excellent conclusion".

The Future

Following this very successful project Canongate have already made a start at the next stage of process automation at the Ram Brewery. This includes replacement of an old pneumatic panel with all the control being integrated to the new plc and various smaller, temperature control and rousing control projects.

David Gray, being of the belief that the client/supplier relationship is of utmost importance, has invited Canongate engineering staff to discuss his thoughts for process automation and control work over the next three to five years.