A flow loop system for study of fibre suspension flocculation
2006 (English)In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, Vol. 21, no 1, 19-23 p.Article in journal (Refereed) Published
A flow loop system for study of fibre flocculation in Suspensions has been developed. The system is designed to simulate the flow conditions in a paper machine headbox. It is equipped with a radial distributor feeding a step diffuser pipe package, after which the flow is contracted in a 2-D nozzle. The flow system is also equipped with a secondary flow contraction, which is aimed for studies of fibre floc rheology. The conditions of the secondary contraction can be changed in order to generate different acceleration rates. The flow system is also equipped for dosage of retention/formation aids to Study the chemical effects oil fibre flocculation. The maximum flow velocity in the system is 16 m/s. Fibre Suspension flows were Studied using a high speed video camera and transmitted infra-red laser light pulse illumination. Images were taken either separately before and after or along the secondary contraction. Images of-fibre flocculation were evaluated by using power spectrum and wavelet transform analysis. By comparing the fibre flocculation before and after the secondary contraction, or by following the fibre floes during the secondary contraction, rheology information oil the fibre flocs call be obtained. By comparing the fibre flocculation information with and Without chemical additions, the effects of chemicals on fibre flocculation can also be studied.
Place, publisher, year, edition, pages
2006. Vol. 21, no 1, 19-23 p.
fibre flocculation, fibre suspension, floc size, flow contraction, flow loop system, image analysis
IdentifiersURN: urn:nbn:se:kth:diva-37683DOI: 10.3183/NPPRJ-2006-21-01-p019-023ISI: 000236358800003ScopusID: 2-s2.0-33645664788OAI: oai:DiVA.org:kth-37683DiVA: diva2:434793