News Article - ABM's new development in Pasteuriser Control Eliminates SLT (26th January 2003)
Well-known process automation and control specialist, ABM Limited has developed a new in-line beer Pasteuriser control system, which eliminates the need for a Sterile Liquor Tank (SLT), reduces capital costs and results in minimised product loss. The system has been developed in conjunction with leading brewer Fullers for their expanded bottling facility at Griffin Brewery in Chiswick.
Faced with having to meet the mounting capital costs of new a Pasteuriser, Fullers approached ABM for help to find a way of achieving their required capacity at a viable cost. ABM tackled the project by looking at how the Pasteuriser control regime could be developed to accommodate as much existing plant as possible and where additional equipment was needed, to use refurbished plant where practical.
As Chris Lindsay, Technical Director of ABM explained:
"When we looked at the existing Pasteuriser control system we realised that by introducing a new approach to the control regime we could deliver Fuller's required capacity, within their capital budget. The brief we gave our systems design team was quite a challenge; how to meet Fullers' required capacity, as well as reduce operating costs and product losses at the same time. We managed to locate a used vessel, a number of pumps and other ancillary equipment which helped us work to Fullers capital budget".
ABM's innovative approach required a radical departure from the usual practice of maintaining required Pasteurisation Units (PUs) by varying temperature at a constant flow rate through the Pasteuriser. Starting from scratch ABM's engineers developed a new control regime based on varying the beer flow rate, at a constant temperature which improves control and stability, so that the PUs are maintained within the required limits. A variable speed pump is used to vary beer flow rate. The system also allows the heat input to be varied, and hence the temperature, this additional facility allows the system to achieve a turn down ratio of better than 3:1 thus reducing the need for phase changeovers and the consequent beer losses.
An additional feature of the system is that the need for a Sterile Liquor Tank (SLT) is eliminated.
Some of the Pasteurisation System Features and Advantages
- Elimination of the SLT, removes a source of potential infection and facilitates a faster and more efficient sterilisation.
- PUs can be maintained more effectively,
- Wear and tear on the Pasteuriser pump is reduced by using an inverter drive.
- Less energy is required to run the pump.
- There is reduced noise from the pump.
- There is no need to have a separate CIP routine for the re-circulation loop, eliminating the need for sub-routines in the CIP control system and therefore reduces the time required for the plant CIP.
Control System Architecture and PLC
The system architecture was developed by ABM to include standard industry systems including:
Industry standard PLC hardware and Standard Endress and Hauser instrumentation.
A high speed, high resolution HMI was provided by ABM which including amongst other things product quality profiles which are user determined including, Pasteurisation Units (PUs), flow rates, temperatures, etc
Above all ABM managed all aspects of the project and completed it on time and to budget.
John Keeling, Fuller's Production Director added:"We were faced with a real problem when we discovered the unacceptable capital cost of a new Pasteuriser. ABM came up with an excellent solution and I'm delighted with the results. The new system is easy to operate, uses less energy,and has resulted in reduced losses and improved quality."