In November 1994, HMIP launched the 3Es project in a bid to show that integrated pollution control (IPC) is "extremely good value for money". The methodology seeks to identify the scope for improvements in emissions, efficiency and economics by optimising processes in line with the "best available techniques not entailing excessive cost" (BATNEEC).
Allied Colloids agreed to work with HMIP to identify savings from two IPC-authorised processes and its effluent treatment plant. An interim report published last year identified potential savings of £1.5 million (ENDS Report 248, pp 6-7 ).
The final project report shows that many of these savings were achieved in the first six-month implementation period with modest engineering expenditure of £70,000.1 It concludes that "BATNEEC may not necessarily require expensive `end of pipe' solutions."
The biggest savings have been achieved on the P199 intermediates plant. Improved checking of breather valves, and replacement of pipework and gaskets which were considered susceptible to failure, is believed to have halved the likely annual cost of pollution events to £150,000.
Measures to reduce plant downtime and increase throughput have also proved highly effective. Over half of the downtime was caused by inventory control and scheduling between different product runs - representing a lost annual profit of £180,000. Emissions of methyl chloride increased 80-fold during changeovers between two products.
Allied Colloids decided to minimise manufacture of the minor product and obtain it externally. Plant downtime caused by storage and scheduling problems has been cut by a third, and mechanical breakdowns halved. Overall, more efficient use of the plant has produced an annual benefit of £233,700.
The reduction in emissions and associated cost savings has not been quantified. But the interim report suggested that a further £160,000 could be saved by minimising fugitive and primary emissions.
Further annual savings of £44,000 will be achieved by improvements to the effluent treatment plant which will generally give a one-year payback. Similar savings are likely to flow from possible upgrades to the activated sludge system and the use of carbon dioxide instead of hydrogen chloride as a neutralising agent.
Work is less advanced on the third plant in the study, which produces liquid dispersion polymers. However, 280 issues have been identified which could yield savings of £3 million. The main source of emissions and inefficiency is interruption to the process caused by imbalances between reactor lines and the process driers. Allied Colloids has developed a simple spreadsheet to allow better scheduling.
Production Director Alan Whitehead commented that what the project "clearly demonstrates, not just to Allied Colloids, but to many companies involved in process industries, is that cost savings and productivity gains - bottom line benefits - run in parallel with environmental benefits." The company now intends to apply the 3Es approach elsewhere on the site.
HMIP has handed over the development of the 3Es methodology to Business in the Environment. The two organisations have published a guide to the methodology,2 including preliminary results from five other industrial sites in the north of England (ENDS Report 251, pp 5-6 ).
All participants have found that the approach requires "considerable time and effort". Full cost savings have not yet been identified, but initial results are described as "very encouraging".
For example, ten improvement projects have been identified on Hickson & Welch's nitrotoluene process at Castleford, Yorkshire. The capital cost is put at £75,000, but should yield direct savings of £500,000 in reduced water charges, energy costs and product losses, and improved plant availability.
Significant improvements to start-up emissions were identified at Alcan Smelting & Power's coal-fired power station at Lynemouth, Northumberland, with expected cost savings in the low £10,000s. However, no figure has yet been offered for the economic benefits at the other three sites.