O PAPEL vol. 84, N.o 5, pp. 84 - 89 - MAY 2023
2 Kemira Chemicals NV/SA, Netherlands.
3 Kemira Chemicals Inc., Brazil.
4 Kemira Asia Co., Ltd, China.
ABSTRACT
Paper manufacturing in the neutral-alkaline pH range
requires a rigorous microbiological control program in
order to avoid runability issues caused by slime growth on
machine surfaces. Oxidative biocides, especially stabilizedchlorine compounds, are most commonly used in wet-end
for controlling pink slime growth. However, chlorinebased programs do contain the risk of causing machine
corrosion damages as an unintended and costly side effect.
Running with significantly lower chlorine levels would
naturally alleviate the corrosion issue, however, it can result
in massive uncontrolled slime growth. Therefore, it would
be beneficial to discover a new antibiofilm chemistry,
specifically targeting surface-attached bacteria. Using this
kind of biofilm-targeted chemistry would enable reducing
the chlorine dosing, without facing pink-slime issues.
In a university collaboration project, a large library of
molecules was screened with the purpose of identifying a
promising new antibiofilm chemistry. The project led to the
identification of a new molecule, B11. This paper shows the
results obtained from the first B11 tests in authentic paper
making conditions. It demonstrated biofilm inhibition at a
uniquely low concentration of 0.05 mg/l. At this dosage level,
its magnitudes are more effective than any organic biocide
molecules currently on the market. This new technology
has great potential to become the antibiofilm product of
choice, when reduction of chlorine-chemistries is perceived
as beneficial. This could become necessary due to on-going
corrosion issues with machinery or in connection with
water system closure project. A biocide program including
a very low daily consumption of B11 and reduced dose of
chlorine-compounds enables running a paper machine with
maximized corrosion safety and effective biofilm control.
Keywords: paper machine, microbiological control, biocide,
biofilm, slime, chlorine, corrosion