The EVO 56 Defibrator system– the obvious choice at Medite

Apr 26, 2011

Medite Europe Ltd, the manufacturer of Medite, onThe EVO 56 Defibrator systeme of the leading European brands of Medium Density Fiberboard, recently eplaced two original L44 refiners installed in 1982 with two new EVO 56 Defibrators.

When considering this investment, Medite carefully weighed all of the advantages and disadvantages of this new defibrating system. The determining factor was the low life cycle cost of the EVO system resulting from full utilization of single rotation and tangential discharge as well as the superior dewatering capacity of the plug screws.

Other important factors influencing Medite’s choice of supplier were energy consumption and resin savings. What’s more, the installation permitted Medite to extend its MDF product range and increase total production capacity to in excess of 450,000 m3.

Medite, based in Clonmel, Ireland, is a part of the Coillte Panel Products Division within the Coillte Group, the Irish semi-state forestry company.

Fast and efficient installation

Customer and supplier cooperation linked with careful logistic planning and pre-engineered concepts, made it possible to achieve a fast and efficient installation and start-up within only three months and with only two days stoppage. Team work, years of experience and a choice of skilled sub contractors is the key to efficient installation. Joe Kennedy, Director, Innovation Coillte Panel Products puts it this way: “Valmet’s technical and field staff is a pleasure to work with; they share their knowledge with our own technical and production teams in a very open way and are supportive to our overall development plans. “Against this background we selected the supplier of the new EVO 56 Defibrator systems. We knew we could work together against an extremely short project plan to design, supply and install the units on time and start up with confidence on a 24/7 basis. “The new EVO 56 Defibrator system was the obvious choice for us after looking at what other suppliers had to offer.”

Joe Kennedy “Valmet’s technical and field staff is a
pleasure to work with; they share their knowledge with our own technical and
production teams in a very open way and are supportive to our overall
development plans."

Joe Kennedy,
Director, Innovation Coillte Panel Products.

Two complete EVO Defibrator systems

The installation included two complete EVO Defibrator systems including surge bins, screw feeders, preheaters and defibrators, and a double system that enables Medite to run fiber through a continuous press with three layers. One fiber system feeds the top and bottom layers and one feeds the middle layer. In this way Medite can vary the fiber properties of the board’s middle layer and surfaces. Medite’s contract for replacing the two original L44 refiners with two new EVO 56 Defibrators required a number of operational improvements. Now, after more than a year of operation, the results are in.

Energy savings

Energy saving was the most challenging target to reach. Valmet and Medite staff collaborated in a number of trials to determine the correct refiner segments for achieving significant energy savings. Currently, the segments on the machines provide a very low 90 kWh/ton of fiber.

Resin saving impacts the environment positively

Resin consumption has been reduced considerably, by at least 15% compared with the former lines as a result of the very uniform fiber quality and flow that the system produces. Now resin dosages are according to real production requirements rather than overdosing to ensure adequate levels. As a positive consequence, Medite can now produce board according to CARB2 specifications, which measures airborne emissions rather than the amount of the formaldehyde in MDF. While not yet an established standard, the growing numbers of suppliers and retailers of home products specifying in this type of production suggests it could become the standard for the industry. Production according to CARB2 was not targeted from the beginning at Medite, but an advantage the EVO system made possible.

Increased dewatering capacity reduces dryer energy consumption

Valmet has installed state-of-the-art dewatering on the two new lines. Plug screws of the latest design fitted with dewatering plug pipes mean that a significantly larger amount of water can be squeezed out of the chips, which reduces the dryer load in the drying system. This has meant that production in the dryer could be increased significantly without adding more heat, another energy saving measure.