TITLE:
Settling/Sedimentation Followed by Sorption with Pinus sylvestris Sawdust as “Green” Sorbent: On-Site Treatment of a Real Industrial Wastewater
AUTHORS:
Fabio Kaczala, Marcia Marques, William Hogland
KEYWORDS:
Industrial Wastewater, Treatment, Sorption, Sawdust, Pinus sylvestris, Sedimentation
JOURNAL NAME:
Journal of Environmental Protection,
Vol.5 No.5,
April
18,
2014
ABSTRACT:
Whereas
the pulp and paper industrial sector—considered the second highest consumer of
freshwater in Europe—has already been provided with sufficient wastewater
characterization and treatment technologies, other wood-based industries (e.g.
furniture, floor production), which do not use water for manufacturing
processes, generate different wastewater streams after: 1) cleaning/washing of machinery that
applies adhesives and coatings onto wood surfaces; 2) cleaning/washing of
machinery that applies specific products for the curing phase of adhesives; 3)
cleaning/washing of sharp planar blades used for the sawn process and to
prepare wood surfaces for the adhesive application; 4) cleaning/washing of the
floor; 5) cleaning/washing of trucks and vehicles. The dilution of
low-volumes of highly polluted wastewater is not acceptable any longer since
conventional treatment plants are not designed for these types of industrial
wastewater. There is
a need for proper characterization, treatability studies, designing and testing
alternative small size and cost-effective treatment systems for on-site
implementation. Treatment systems based on sorption mechanisms are flexible,
easy to operate and generate less sludge and several low-cost sorbents
generated by forestry activities have advantageous physico-chemical
characteristics. The current paper presents the preliminary results from a
pilot treatment system consisting of an equalization tank,
settling/sedimentation and two sorption reactors in parallel using Pinus sylvestris sawdust as sorbent
implemented as part of an integrated water management plan in a wood-floor
industry. The simple to operate and cost-effective pilot treatment system performs
satisfactorily during an initial period of operation. The study shows an
average 39% - 54% reduction of TPH; 17% - 38% reduction of oil; 2% - 15% of
reduction of COD and; 11% - 74% reduction of most toxic metals but for Co, Ni
and Zn in the system B. Based on these results, Pinus sylvestris sawdust is a potential low-cost and abundant material to be considered for
industrial wastewater treatment plants.