A Spirax Sarco fl ash steam recovery system is delivering direct energy savings of 10%, plus a further 10% in indirect savings, at De Mulder & Sons in Nuneaton.
The system has also dramatically cut visible plumes of flash steam from the site, which is one of the UK’s largest processors of meat and poultry residues.
De Mulder & Sons uses around 25 tonnes per hour of steam to dry and sterilise animal products. Before the new system was installed, the resulting flash steam from the returning drier condensate was vented to atmosphere. The company decided to recover this wasted energy as part of a groupwide policy to save energy and reduce visible emissions.
Spirax Sarco was called in and, working with the PDM team, designed, built and delivered a complete packaged flash steam recovery system. Now, condensate and fl ash steam is fed from the driers to the fl ash recovery vessel, which separates them into two streams. Each stream then flows through its own dedicated plate heat exchanger, which transfers the energy in the fl ash steam or condensate to the boiler feedwater. This raises the temperature of the pressurised feedwater to around 130oC, rather than the 90oC typically achieved before flash steam recovery was introduced.
There are five boilers on the site, of which three were running prior to the Waste Heat Recovery Unit installation. Raising the feedwater temperature and therefore the system efficiency, has allowed one of the boilers to be taken off-line.
“The modular approach was helpful for the installation and the Spirax Sarco team has been very supportive.”Operations Director Mr. Rob Ratcliffe
The flash vessel, heat exchangers and associated peripheral equipment were all supplied to Nuneaton as a skid-mounted, engineered system. With all the major assembly work carried out at Spirax Sarco’s Cheltenham facility, the complete recovery system was integrated with De Mulder’s existing plant over a normal weekend shutdown. “The modular approach was helpful for the installation and the Spirax Sarco team has been very supportive,” says Mr. Ratcliffe. Project management was integral to the service provided by Spirax Sarco. Close co-ordination between the Spirax Sarco
team and the client ensured that the system was delivered on time and on specification. This further minimised any disruption during installation and commissioning.