“The remit to ANDRITZ was a challenging one,” says Marcelo Montanhese de Lima, Bracell Tissue Project Sr Manager. “Our owner, the Royal Golden Eagle (RGE) group, wanted to create the biggest and the greenest pulp mill in the world here at Lençóis Paulista mill. This meant that there must be no fossil fuels used in the mill, NOx emissions kept to a minimum, and very low water consumption.
“Last, but by no means least, RGE wanted a mill that would switch between kraft pulp and dissolving pulp as quickly as possible according to market demand – which is a challenge in itself as the two processes are completely different.”
Bracell began operations in Brazil in 2003 with the acquisition of BSC (Bahia Specialty Cellulose) and Copener (Florestal) in Bahia state in the east of the country. In August 2018 the company expanded its operations by acquiring Lwarcel Cellulose in Lençóis Paulista, São Paulo state.
“The acquisition of Lwarcel pulp mill in Lençóis Paulista represented the first step in the Project Star journey,” says Montanhese de Lima. “And this was a very ambitious project; to create a mill that will produce up to 1.5 million t/y of dissolving pulp, or 3 million t/y of bleached kraft pulp, with the ability to switch when necessary.
“This meant that not only were we embarking on a mill of huge dimensions, we also had to have specialist technology installed for continuous batch cooking for dissolving grade pulp. Added to this we had the environmental factor, including completely eliminating the use of fossil fuels with the installation of gasification before the lime kiln, as well as numerous other environmental factors to ensure we stuck to the remit of creating the greenest of mills.”
In stepped ANDRITZ to take on the enormous challenge. Awarded the contract in 2019 on an EPCC basis, to include engineering, procurement, construction and civil construction, ANDRITZ scope of supply included the complete wood processing plant, the world’s largest recovery boiler, two hardwood fiberlines, two independent pulp drying lines and the world’s largest non-condensable gas treatment system, focusing on the use of side streams in the recovery cycle. Also, ANDRITZ was responsible to deliver the Training Simulator (OTS) for the complete pulp mill.
Rafael Sirtoli, Director of Operations, ANDRITZ Brazil, says, “This really was a great project to be part of creating one of the largest and most sustainable mills in the world, at the same time as supplying flexible fiberlines that can handle both dissolving and kraft pulp, was a real challenge.
“With this project we delivered our world class technology on an immense scale, including the high-capacity wood processing, the largest HERB recovery boiler ever made, and our self-developed A-ConFlex technology to enable the switch from kraft to dissolving pulp in a very short time while keeping production at a high level.”
Sirtoli adds that the environmental performance of the fiberline and pulp drying lines at the mill enables the highest yield in the production of pulp. “The consumption of wood is the lowest possible with this combination fiberline and drying supplied,” he says. “The DD-Washers also lead to the lowest possible chemical consumption. Add this to the recovery boiler which, has the optimum parameters when it comes to the lowest emissions, and we have a mill that has now resulted in the lowest environmental loads possible.”
Rafael Sirtoli
Director of Operations, ANDRITZ Brazil
ANDRITZ got to work on the project starting in 2019, and 25 months later, after a demanding journey of manufacturing, transporting and erecting some of the largest machine parts the pulp world has ever seen – as well as the added challenge of the pandemic – the mill started up on time.
“From the first project order of the recovery boiler to start-up was just 25 months,” says Montanhese de Lima. “We had some 12,000 people here working on the project, which was a challenge, particularly when the pandemic struck, but the cooperation with ANDRITZ was smooth and efficient and together we managed the situation successfully.
“The sequence of all the installed technology from ANDRITZ including wood processing, recovery boiler, fiberline and pulp drying, as well as the non-fossil fuel energy matrix was commissioned and started up smoothly. It really was an amazing experience putting this giant into operation.”
Commenting on the operation of the HERB recovery boiler, Montanhese de Lima says, “This was an incredible part of the project, a unique concept, and a combination of many things. The recovery boiler has already reached a production rate of 13,000 tds/d virgin black liquor load, which is something of a dream.
“We have running joke that the recovery boiler at this mill is not only the largest in the world, but also in the galaxy!”
Marcelo Montanhese de Lima
Bracell Tissue Project Sr. Manager
ANDRITZ full scope of supply on EPCC (Engineering, Procurement, Construction and Civil Construction) basis – four of the six most important process islands in the pulp mill:
The HERB recovery boiler supplied by ANDRITZ is the world’s largest. The HERB recovery boiler features energy-efficient flue gas cooling and feed water preheating technologies to maximize steam production for power generation. It will produce approximately double the amount of electric power required to operate the entire pulp mill. Thus, the mill will be completely self-sufficient in energy supply. The recovery boiler will be capable of generating sufficient power to meet the demand of a city of around one million people. The HERB recovery boiler is designed for long operating periods without requiring water wash, thus achieving highest availability.
The boiler also meets the tight environmental requirements of the mill and in addition, odorous gases as well as methanol are burned in the boiler ensuring odorless operation.
