WRL Team Back from Brazilian Field Investigation
Dr. William Glamore and Alessio Mariani have successfully completed the specialist investigation on the effluent of Veracel Pulp Mill, in Eunapolis, state of Bahia, Brazil. The study was undertaken for Gunns Limited as part of an extensive environmental assessment in relation to the proposed construction of a Tasmanian pulp mill.
WRL’s investigation focused on the physical properties of the fine particulate (floc) within the pulp mill effluent. Once discharged the particulate may disperse or settle to the bed and accumulate as a dense floc mat with significant environmental impacts. WRL’s study assessed the fate and transport of the particulate matter through a range of physical model studies determining the:
- Floc size evolution under different rates
- Settling rates of flocculated material
- Critical shear velocity for floc mat and re-suspension rates
- Partitioning rates of flocs mixed with seawater
The studies made use of jar testing, settling column and recirculating flume tests designed and constructed onsite in Brazil. The equipment used in this investigation comprised:
- Particle size analysers: Malvern Mastersizer 2000, Sequoia Lisst-25X, Pola Particle Counter 2000
- Jar test apparatus Milan JT102
- Particle Image Tracking (PIT) techniques
- Acoustic Doppler Velocimeter Sontek/YSI 16-MHz MicroADV
- A custom built re-circulating flume designed specifically for this study
The successful undertaking of this complex experimental study in Brazil, would not have been possible without the collaboration of the Universidade Federal do Rio de Janeiro as well as the environmental team of Veracel Pty Ltd.