Print & Packaging at Operational Group

Print and packaging businesses can boost efficiencies and control costs in manufacturing processes by re-using their waste energy and optimising equipment and systems, using engineered solutions from Operational Group.

At Operational, we help print and packaging manufacturers working with materials including paper, plastic, foil and cardboard to recover and re-use heat energy, and to optimise various equipment types and systems.

Our specialist engineers understand the problems manufacturers face in reducing energy consumption and optimising equipment costs for greater efficiencies. The benefits and return on investment are considerable.

Paul Bedworth, Operations Director for Operational UK, said food packaging manufacturers represent a major part of Operational Group’s work, producing plastic, polythene and foil packaging for fresh and frozen food products and other printed solutions.

He explained: “In the printing and packaging industry, a mixture of flexographic, rotogravure and coating processes use hot air to dry the inks and coatings on the substrates. This drying process evaporates the solvents from the liquid ink and recirculates or exhausts the solvent laden air from within the dryer. Prior to discharge to atmosphere these exhaust gases are passed into air pollution abatement systems where the solvent concentrations are reduced to maximum allowable levels set by legislation. This abatement process may use heat to destroy the solvents, or alternatively, a solvent recovery system to recover the solvent for re-use.

“Typically, in the UK, regenerative thermal oxidiser (RTO) systems are primarily used to reduce the solvent concentrations, ie. Volatile Organic Compounds (VOC’s), down to the required legislative levels. The destruction of these solvents in the RTO is accomplished using elevated temperatures of up to 1000oC and this thermal energy, contained in the exhaust gases, is absorbed into ceramic beds and re-used to pre-heat incoming solvent laden air from the presses. Such RTO abatement techniques offer very high VOC destruction efficiencies, often in excess of 99%, whilst the ceramic beds provide thermal efficiencies of up to 95%.”

Further efficiencies can result when ‘auto-thermal’ conditions, often as low as 2g/m3 solvent concentrations, are achieved requiring no auxiliary fuel addition via the burner. Under these conditions excess heat is often available which Operational can recover and reutilise in the press dryer heating system or elsewhere in the manufacturing process.

“Such highly-efficient processes, recycling thermal energy that would otherwise be discharged to the atmosphere, is one of the many ways Operational can help its clients save money.”

Optimisation of the drying process within the printing machine is another important aspect of Operational Group’s services.

The process for optimising a dryer usually starts by establishing an understanding of the client’s process and the operating conditions of the printing machine, generally by a detailed survey. Identifying the improvements and benefits that can be achieved by optimisation of the dryer requires technical expertise which Operational has developed over many years of experience. By making improvements to the dryer, balancing air velocities, distribution and pressures, often results in reduced energy consumption, improved safety & product quality and a reduction in exhaust volumes to atmosphere.

The upgrading of dryers, changing of the heating source, adding solvent monitoring equipment and air balancing, will give positive improvements to the dryers ability to evaporate the solvent from the ink in a much more efficient manner. Our experience in dryer technology allows us to tailor the optimisation design to any specific machine. Our installations can now allow dryers to operate within region 2 of EN1539 legislation giving added safety and benefits to the drying process.

Optimisation also reduces the exhaust air volumes from the press dryers which reduces the size of the abatement plant and, because of increased solvent levels in the exhaust gases, further reduces energy and operating costs.

Paul added “Our optimisation work can enable clients to add extra printing presses and increase production capacity without the need to increase capacity of their existing abatement plant, saving hundreds of thousands of pounds in capital investment.”

“A full range of advice and surveys are available for businesses to consider all options available to them. We have case studies from many different sectors explaining the benefits our clients have seen and also technical papers to share best practice.

Paul emphasised: “There are normally many efficiency gains to be made within the dryers, abatement plants and energy recovery systems. With our in-house project engineers, electrical/control engineers and process engineers we can design, engineer, deliver, install and commission full turnkey installations.

“For over 30 years we’ve been helping our clients make significant improvements to energy consumption by optimising processes and recovering & reusing waste energy. Once the changes are made, our maintenance and technical support services ensure equipment, monitoring and processes are kept at optimal standards for ongoing efficiencies and return on investment.”