Odorless pulp mill in successful operation
The sulphur in the cooking process can result in bad odor in the surroundings of a Kraft pulp mill. Together with the odor, sulphur compounds can also be an environmental problem since they are released to the atmosphere. Although emissions are becoming lower as mills are upgraded, odors have continued to be a problem for people living close to the mills, because of the very low odor threshold of sulphur compounds.
Valmet has delivered a unique, practically odorless mill to CMPC Riograndese Ltda in Guaíba, Brazil. The design guidelines were to not vent odorous gases and to aim for zero smells. The gas handling system collects and controls odors from more than 100 sources and all process areas are included. Incineration of non-condensable gases is ensured through multiple, simultaneously available incineration locations.
According to CMPC it can be said that the system availability is practically 100% and there is always a system ready to handle NCG and prevent gases from being emitted to the atmosphere. This meant production losses of about 1300 Adt per year are avoided because the mill does not have to shut as it used to when the NCG incinerator could not handle the load. Also the emissions of diluted non-condensabel gases (DNCGs) and concentrated non-condensable gases (CNCGs) have been prevented 24 times in 12 months.
Learn more about the odorless pulp mill concept
A Valmet white paper, available HERE, reviews the odorless pulp mill project, including the emphasis CMPC placed in the concept of the odorless mill in Guaíba and its surroundings. The paper outlines the chosen technical solutions to achieve this targe, including the necessity of ensuring that odorous gases are treated also in shutdown and emergency situations.
Download and read the white paper and give your Valmet representative a call to discuss the future of odorless pulp mills.