Title:
Mixing Performance of Energy-Saving Gravity Mixer for Powder Materials
Author(s):
Tek Raj Gyawali, Buddhi Raj Joshi, and Matabee K. Maeda
Publication:
Materials Journal
Volume:
116
Issue:
2
Appears on pages(s):
3-8
Keywords:
gravity fall; interparticle collision and impact; mixers; powder materials; pre-mix; splitting and recombination
DOI:
10.14359/51714449
Date:
3/1/2019
Abstract:
Powder materials are difficult to mix in conventional mixers in terms of uniform distribution and producing the homogeneous mix. The “pre-mix” method was used to mix cement and fly ash in an energy-saving gravity (ESG) mixer. Pre-mixed powder was flattened circular and six samples were taken from symmetric perimeter and then mixed with water in a mortar mixer. Specimens of each sample were made for compressive strength tests. The variation coefficient of compressive strengths in a 1-day test (steam curing) was 3.9% with a comparison of 4.7% in a mortar mixer, and a 3-day test (air curing) was 2.11% with comparison of 8.9% in a mortar mixer. The mixing performance of the ESG mixer was verified that only its six units are sufficient to mix two different powders uniformly due to the mechanism of interparticle collisions and impact with further enhancement of splitting and recombination actions. This system was used in marine construction site for real application.
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