Abstract:
:Guar gum is used in low concentrations as a drag reducing agent in turbulent flows to significantly accelerate flow in oil pipelines, oil well operations and aqueous systems. Drag reduction also promotes a decrease in energy demand in pumping systems. However, the polymers undergo mechanical degradation and lose the ability to promote drag reduction over time. In this paper, the drag reduction, the power required by the pumps and the degradation of the guar gum were evaluated during a turbulent flow of an aqueous solution containing the biopolymer. The results indicate the mechanism of degradation of guar gum by the hydrolysis of the bond α (1 → 6), liberating the galactose, which justice to the loss of efficiency throughout the process. An understanding of this mechanism should allow for the development of more mechanically resistant polymers and the increase of drag reduction capacity over time.
journal_name
Int J Biol Macromoljournal_title
International journal of biological macromoleculesauthors
Motta MVL,de Castro EVR,Muri EJB,Costalonga ML,Loureiro BV,Filgueiras PRdoi
10.1016/j.ijbiomac.2018.09.214subject
Has Abstractpub_date
2019-01-01 00:00:00pages
23-28eissn
0141-8130issn
1879-0003pii
S0141-8130(18)34417-9journal_volume
121pub_type
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