“I have been working on various projects here for over 30 years, and I know that ANDRITZ always does a good job. We can always trust that they take full responsibility for the end result.”
Hallsta Paper Mill
Customer satisfaction is everything when it comes to making quality paper. In the competitive world of book printing paper, it is essential that the final product being delivered delights the customer with both features of runability and good surface printability. The only way to really make sure this happens is to start at the beginning – with the quality of the pulp.
Hallsta Paper Mill
In an effort to continually improve the quality of its book paper grades, Holmen Hallsta decided that it needed to look into its water management between the TMP line and PM 12, and particularly at the dewatering stage on the line feeding the paper machine. Magnus Rydstrand, Production Engineer, TMP, Hallsta Paper Mill explains, “We knew in 2008 that there was a problem with the separation of water between the pulp mill and the paper machine. We needed to have clean water going into the paper machine, otherwise we would have to use extra chemicals because any dead fibers going around will darken the water, encourage bacteria to grow, and cause all sorts of problems with brightness and potentially paper quality and runability.”
Due to machine movements and conversions in the past, the dewatering stage between the TMP line and PM 12 at the mill was always considered to be a temporary arrangement, and the plan had been to improve the system as soon as the time was right. In the meantime, the mill managed to acquire two 15-year-old ANDRITZ twin wire presses from another Holmen mill, at the same time as having an ANDRITZ screw press from a DIP line that was shut down at Hallsta Paper Mill in the past. It was decided by the mill that it would be a good idea to utilize all three dewatering presses for the improvement project.
“The twin wire presses we acquired, as well as the screw press, were still in excellent condition, which gives an idea of the engineering and manufacturing quality of ANDRITZ equipment. We decided that utilizing the equipment we had would be an excellent solution for our needs for improving pulp washing for PM 12,” says Rydstrand.
ANDRITZ was the first port of call for the mill and its pulp washing improvement plan, as not only was the equipment known, but also the mill has had some history with the company as a major supplier in the past. Erik Sandgren, Project Manager, Holmen Paper Hallsta, says, “I have been working on various projects here at the mill for over 30 years, and I know that ANDRITZ always does a good job. We can always trust that the engineers, experts, and management take full responsibility for the end results. Also, we like the dewatering technology from ANDRITZ; in fact, we already had 12 twin wire presses installed here before this project commenced, the oldest ones dating back to 1989.”
ANDRITZ was contracted to refurbish, install, commission, and start up all three dewatering presses. This included the overhaul and reutilization of the two second-hand wire presses, the relocation and light overhaul of the existing screw press, rebuilds and relocation of two existing conveyors, installation of a new conveyor, and basic engineering and erection.
The first customer contact was in January 2015, with the contract and project start taking place in March 2018. Start-up took place just seven months later in November 2018, after major works undertaken by Hallsta Paper Mill in civil construction, and the installation of tanks, pipes and piping, and agitators.
The refurbished presses were connected commissioned and started up during a short shutdown at the mill in November last year.
Mahir Mehinagic, Product Engineer, Twin Wire Press, ANDRITZ, says, “This was a really interesting project we took part in at Hallsta Paper Mill, and the mill team was a pleasure to work with. Even though this was a used equipment project, the presses looked like new when they were installed and started up, and we can all be happy that such reliable equipment from ANDRITZ is up and running again.”