FEATURE: SAPPI SAICCOR
Growing people, not just capacity
With the end of Sappi Saiccor’s latest expansion project finally in sight, Jodie Davies-Coleman took stock of the challenges and successes that the mill has encountered over the last 8 million man hours, through the eyes of the project’s major supplier, Andritz.
Imagine a construction site packed at its peak with 3000 contractors and suppliers, installing and erecting US$ 500 million worth of new machinery. Now imagine this construction site squeezed into an existing pulp mill operating at full capacity. And not just any pulp mill, but the largest producer of chemical cellulose pulp in the world.
Welcome to Sappi Saiccor.
And welcome to one of Sappi’s biggest organic growth sites to date: the Amakhulu Project. The project’s title, Amakhulu, means “big one” in Zulu – a reflection not only of the Zulu culture which surrounds the Sappi Saiccor mill in its location in Durban, South Africa, but also of the great heights that Sappi Saiccor has achieved through its expansion project.
Motivating factors
According to Alan Tubb, Saiccor Chief Executive, dreams of expanding the mill began in 2005, with an increase in market demand and the successful completion of Project Imvula (a debottlenecking project which was Amakhulu’s forerunner) paving the way for a bigger production plant.
“In terms of our diversification strategy, our quality improvement strategy and our environmental strategy, it was the right thing to do to grow the business,” says Gary Bowles, Sappi Saiccor General Manager. To quote Bowles, “continuous improvement is the name of the game” and the Amakhulu project afforded Sappi an opportunity to grow their market leadership.
But what success would the Amakhulu project have if it promoted Sappi’s sustainability principles of People and Prosperity alone, and did not address the Planet. A major motivator of Amakhulu was therefore its leverage of a number of Saiccor’s environmental issues, including the need to reduce the mill’s emission volumes and reliance on fossil fuels.
“By investing in the best modern technology, we have managed to increase our profit margin while decreasing our environmental impact,” explains Tubb. Amakhulu has enabled Saiccor to shut three of its calcium digesters and replace them with eleven magnesium sulphite digesters for their new No.4 Fibreline, which has met EIA requirements of reducing the mill’s dependency on fossil fuels by 20% coal and on the national power grid by a further 20%. Amakhulu has also increased the production of lignosulphonate with the reduced calcium pulping by 30%, resulting in substantial reduction of effluent dissolved solids. Notably, Saiccor has also managed to maintain the same rate of water consumption despite the additional 200 000 tonne capacity, with a dramatic improvement in specific water consumption.
Saiccor’s new No.4 Fibreline will produce on average 870 ADMT/d, brightness 93% ISO dissolving pulp from eucalyptus grandis hardwoods fibres. The additional capacity provided by the fibreline has been designed to service the VSF (Viscose Staple Fibre) market, predominantly in the form of textile products. Amakhulu has also freed up Saiccor’s existing lines for speciality markets such as cigarette filters, nonwovens, hygiene and pharmaceutical products.
Andritz’s contribution to Amakhulu
As the major supplier to the Amakhulu Project, Andritz was instrumental in helping Saiccor realise their goals for the expansion. Sappi has a strong working relationship with Andritz, through their combined involvement in a number of Sappi expansion projects.
This includes Sappi Saiccor’s Mkomazi expansion project in 1993/4, from which Andritz was able to provide Amakhulu with technical experience in pulp drying, bleaching and evaporators specific to Saiccor. Project Director and Sappi Group Head of Technology, Andrea Rossi, explains that this proved a major motivator in choosing Andritz as supplier of the woodyard, fiberline, pulp drying line, and evaporator deliveries. Another motivating factor was Andritz’ ability to offer Sappi Saiccor whole solutions. “Andritz offers a basket of technology,” says Bowles, “that makes our interfacing far more streamlined.”
Andritz experts from Austria, Sweden, Finland and the USA were responsible for the overall design and technical support, whilst the local Andritz office was responsible for supporting the project execution and for providing some on-site expertise.
“Andritz has a very good local technical presence,” says Rossi. Andritz’ South African office sourced many of the materials, platforms, supports, piping, tanks and vessels as well as the local mechanical and piping erection contractors. To round out its team, Andritz hired local site, safety, quality, purchasing and scheduling personnel.
New woodyard technology for Sappi
Since the completion of the Amakhulu woodyard, which included the turnkey supply by Andritz of the receiving deck for the incoming logs, the log washing system, horizontally-fed chipper, chip belt stacking system, chip reclaiming and conveyors to the cooking plant, the woodyard is able to take on a larger volume of logs of up to 6 m in length. Previously, long lengths could only be chipped on one of the existing three chipping lines, with the remaining two lines having a maximum length of 3 m. The Andritz chipper is also able to take logs with a much larger diameter than the current spec of 450 mm, enabling Saiccor to chip the odd oversized logs that are delivered to the mill.
Andritz also supplied a horizontally-fed HHQ-Chipper™ with 16 chipping knives. This is only the second chipper of its kind in Africa (the other being supplied by Andritz to the Republic of Congo), but remains a first for South Africa. When asked why it has taken South African mills this long to invest in horizontally fed chipping technology, Tony Neave (Plant manager –Pulp Preparation, which includes the woodyard) explains that it is always hard to move away from proven technology.
However, since taking the plunge, Saiccor have achieved a chipping rate of 230 wwt/hour – 10% more than the original design rate. This means that a max rate of 4800 tonnes/day is achievable. In terms of general runnability, the chipper is less problematic than Saiccor’s existing chippers and far more user-friendly with a feeding deck which features variable speed control. Saiccor’s new chip conveyor system is also a step-up from the mill’s existing pneumatic conveyor, which resulted in a number of quality issues. “Any improvement you can get in the woodyard ultimately benefits the end product,” says Neave.
Surpassing design targets in the bleach plant and drying line
The technical expertise and efficiency of Andritz was established in their delivery of Sappi Saiccor’s new bleaching plant. The technology for the fibreline includes the delivery of fine screening, oxygen stage, and four-stage ECF bleach plant. The plant is based principally on the mill’s Bleaching Plant 3, delivered by Andritz in 1994-1995, including the six conventional vacuum filters (GasFree Filter technology) for brownstock washing and the bleach plant. This significantly reduced engineering costs for the new bleach plant, which has been operating at 1020ADMT/d – already surpassing its design target of 870 ADMT/d at 93% ISO brightness.
When asked if there were any plans to improve this further, Krish Naidu (Mill Area Manager: Dryer/Bleaching) replies: “Yes, we’re continuously looking to improve the efficiencies of our plants. I’m an engineer, and it’s in my nature to identify process limitations, and de-bottleneck them with implementing sustainable solutions. That’s the challenge!”
Naidu was also involved in Andritz’ turnkey supply of Saiccor’s pulp drying line, which includes the approach flow system, pulp machine, airborne sheet dryer, a densification press, a cutter/layboy, and automated baling line. Working width of the line is 4.06m and the design capacity is 930 MDMT/d.
Most impressive in Andritz’s delivery is the twin wire forming technology on the pulp machine (a new technology for Saiccor) and the inclusion of a PrimePress X shoe press from Andritz Küsters in the press section. The PrimePress X withdraws a considerable amount of water from the pulp prior to it entering the Fläkt airborne dryer. Through this integrated shoe, line forces can be increased and dwell time in the nip extended. The press operates with an extended nip at 1200 kN/m, significantly higher than the existing final press sections at the mill. The PrimePress X will reduce Saiccor’s operating costs through its increased moisture extraction from the pulp, necessitating less steam in the drying plant.
Next in line is the Andritz Fläkt airborne sheet dryer with a heat recovery system. Following the dryer, an Andritz Küsters PrimeCal Hard is utilized as a densification press for finishing of the pulp web sheet prior to the cutter. Andritz delivered the cutter/layboy and automated baling line (baling, pressing, wrapping, and palletizing equipment), including the BaleMatic™ control system.
“This was a very challenging project for us from several aspects,” says Bernd Asbeck, Andritz’s Project Manager for the drying plant. “The drying of dissolving pulp was a new process for us.” The physical design, especially that of the wet end structure, was significantly influenced by the low pH of the stock. “A simple thing like a general walkway, which we would typically produce in aluminum, had to be fabricated from stainless steel in order to handle the corrosive environment.”
Brought on by a decline in global availability, the skyrocketing stainless steel prices formed a major financial drain for the Amakhulu project. “It was a major challenge to manage costs and the sourcing of stainless steel, as we were competing not only with international demand for materials, but also a strong local demand with the 2010 Soccer World Cup construction beginning,” explains Rossi. Fortunately, Andritz was able to reserve the majority of materials required before the construction of stadiums and other basic infrastructure began in South Africa.
In addition to the technical challenges, Asbeck and his team met the usual project challenges – plus some. “First was time,” Asbeck says. “We were on a tight schedule, with installation beginning in May 2007 and start-up one year later. We were doing the full erection of the drying line systems, not just erection supervision. So, much of our work involved finding quality-minded sub-suppliers in South Africa, and documenting their QA programmes. This required special focus.”
In addition, precious “real estate” inside the mill was at a premium. “There were only small areas for laydown and erection preparation available to us because the mill was in full operation during our construction and installation work,” Asbeck recalls.
Despite being placed under tight deadlines and in an even tighter geographical location with limited access for civil construction, the drying line was finished two days ahead of schedule. Since the production of the first bale on the 13 May 2008, and the successful completion of its performance test runs towards the end of last year, the pulp drying line has “exceeded many expectations,” says Naidu.
“We have a very good working relation with Andritz, which can be seen in the successful installation of both the bleaching plant and drying line within schedule constraints,” he explains. “My experience is that Andritz is team driven and customer orientated in terms of satisfying our needs. Saiccor’s requirements and expectations were tabled by the Sappi team and Andritz designed around them, resulting in common solutions.
Conquering a very large evaporator
Andritz was further chosen to supply Saiccor’s newest evaporator for the Amakhulu project, which is currently the largest of its kind for magnesium sulphite applications - a six-effect plant designed to evaporate 370 tonnes of water each hour, and to reduce incoming black liquor from approximately 81.5% water to 42% water.
The units are especially constructed for the new fibreline’s magnesium sulphite process, with special emphasis on the production of clean reusable condensates by a condensate segregation system where dirty condensate is separated and fed to the stripper. The evaporators are equipped with a stripper and a methanol recovery unit for stripping the water of volatile gases (which are then combusted in the boiler), as well as other specific features required for the process.
Saiccor’s new multi-effect evaporator is also very different to the mill’s existing mechanical evaporators – a switch-over motivated predominantly by the increased reliability of a multi-effect evaporator. The existing evaporators necessitate continual planned shutdowns by the mill in order to mechanically clean scale build-up, while the new multi-effect evaporator has internal heat surface washing in the sulphite liquor stages (unique to Andritz).
But how exactly does one erect one of the world’s largest evaporators? First, Saiccor had to seek approval to specially construct three private on- and off-ramps from the nearby national highway, which would enable the Amakhulu team to transport the biggest shipments possible directly to the mill. Secondly, contractors had to lay down an area in a nearby flood plain where containers of equipment could be placed while awaiting installation.
The evaporator’s first four effects were transported whole, while South Africa’s weight restrictions on national roads forced the last two effects to be dismantled at source, rebuilt into smaller pieces and then transported by road. “It certainly forced Andritz to think out the box, which they did without complaint,” reflects Rossi. Finally the evaporator was positioned in place with a 450-tonne crane – one of the biggest in South Africa.
The evaporator has yet to the fully commissioned, although the plant has been successfully run for short periods at a time. The delay has been a knock-on affect of Saiccor’s troubled digester. “Our system is a closed-loop, and we need the digesters to work together with the recovery boiler and evaporation. If we have just one part of the loop missing, the other parts are unfortunately affected,” explains Colin Reddy (Mill Area Manager: Evaporator and Recovery).
The delay in the digester plant was initiated by a leak of sulphur dioxide gas from a newly commissioned pipeline in October last year. Although the malfunctioning pipeline was quickly and efficiently isolated by the technical staff at the mill, the digesters subsequently had to undergo a further planned shutdown while a more thorough investigation was made.
‘Dynamic simulation is the way to go’
Included in the Andritz delivery for the evaporator and new boiler is an IDEAS Simulator which provides a dynamic simulation identical to the DCS which is used for dynamic operation trouble shooting, verification and operator training. The simulator has been engineered to reflect Saiccor’s chemical recovery and boiler processes, although there is an interest in simulating the entire mill in the future.
Essentially, the simulator allows operators to practice handling disturbances in a safe, virtual environment. By implementing FAT (Factory Acceptance Testing), Colin Reddy and his team were able to perform logic testing on the simulator rather than on the plant itself and thus isolate and remove problems ahead of time, with no tangible cost to the machinery.
Although it still needs to be fine-tuned to mimic the smallest details of Saiccor’s recovery process, the Simulator has been invaluable in training approximately 200 new and existing staff at the mill. “The IDEAS Simulator has been extremely helpful for the start up and training of operators,” says Rossi. “With skills levels as they are in South Africa, dynamic simulation is the way to go.”
Project challenges
Despite the successful deliveries by Andritz, the Amakhulu project was not without challenges. Across the board, the biggest challenge to the expansion project was the resulting congestion and logistical dilemmas of expanding a brownfield site.
In order to ease congestion, a number of secondary buildings such as the training facilities, canteen and locker rooms had to be demolished and rebuilt elsewhere. “We also had to carefully plan and manage deliveries, with the long delivery items such as the recovery boiler and the turbine generator being awarded first,” explains Rossi.
With over 3000 people on site during peak construction, tremendous pressure was also placed on mill facilities such as housekeeping and the canteen, and further necessitated comprehensive induction training for the large majority of labour that had not previously worked in a pulp mill environment. This certainly paid off, with an injury frequency rate at Sappi Saiccor of just 0.2% and LTFI (Lost Time Frequency Index) of 0.18 in the eight million man hours worked throughout the project.
Facing the recession
With mills around the world forced to close their doors, one would have thought that the global recession would have been a major challenge to Amakhulu. However the expansion was almost finished before South Africa was impacted by the recession, although the plant was forced to run at approximately 70% of its total new capacity for a number of months (with regards to aspects of the project such as the digester). “It is currently ramping back up to full capacity,” says Gary Bowles, General Manager.
“Being a cyclical industry, we anticipated a dip in demand although the magnitude and speed of it caught me unawares,” says Rossi. Despite this, Rossi confirmed that Andritz and all of the other main EPC contractors came within the Sappi budget. “Other than the civil construction and digester plant, everything else in the project remained within our project budget and came in on time,” he explains. “This huge investment has not only shown Sappi’s commitment to the region but it has also modernised our assets and satisfied our customer demands with regards to supply and quality.” It certainly places Saiccor in an even stronger position to take on any competition that the future may bring.
Growing the community
Gary Bowles and Andrea Rossi earmark one of the biggest successes of Project Amakhulu as the growth and development of the mill’s young engineers, artisans and process personnel. Says Bowles: “The key success is our personal growth through this project. People are wonderful assets to utilise.”
Amakhulu drove this growth outside of the mill too. As Managing Director Alan Tubb explains, Saiccor set up a SETA (Sector Education and Training Authority) approved training school in the local community for the duration of Amakhulu supported financially by Andritz and other EPC suppliers and contractors. Over the course of a year, this facility trained 120 people directly for the project and 60 more in basic construction skills. From these skills provided by Sappi Saiccor, members of the local community were able to build their first brick homes. Further, combined with the 1000 temporary and permanent jobs offered by the project, Sappi Saiccor was able to dramatically reduce crime in the area and improve conditions for many of the local population.
Not only was the Amakhulu Project successful in blending expansion in its own plant with expansion in the local community, but the project also successfully integrated the different cultures and nationalities represented on site (of which there were many). “The existing mill staff were in full support of the Amakhulu Project and helped out where they could. And without the support of your own people, it just doesn’t work,” comments Bowles.
The additional support of Andritz’ people has eased Sappi Saiccor’s new mill into its first successful production runs as well. As Andrea Rossi explains, “We are extremely happy to have worked with all the Andritz team members. They have had a very positive attitude and were willing to find the solutions to ensure we met performance requirements. Most site workers and subcontractors were very happy and proud to work for Andritz.”
