Date of Graduation

1999

Document Type

Thesis

Degree Type

MS

Committee Chair

Richard Turton

Abstract

The objective of this research was to develop a technique to agglomerate cement powder. This was done to facilitate its transportation and to prevent problems faced in conveying cement powder such as cement dusting as well as respiratory problems for workers coming in contact with cement dust. The final agglomerates formed were required to produce concrete with properties as close as possible to that of concrete formed from untreated cement. The agglomeration was carried out in a blender by adding a binder solution. A number of binder-solvent combinations were tested. Successful formation of granules was achieved and subsequently these were milled in a ball mill to form powder and then added to water to make cement slurry. This slurry was then subjected to three main testing methods in order to compare its properties to that of untreated cement slurries. These three tests determined concrete strength, slurry viscosity and setting characteristics of the concrete slurry. These granules were also tested for resistance to abrasion and attrition by carrying out a Rotap Sieve test to ensure that they did not break or crumble down during transportation. A technique to successfully granulate cement powder using a binder solvent combination of methanol with 1.5 wt % calcium chloride and 0.3 to 0.35 wt% tartaric acid was found. This binder solvent combination resulted in relatively strong granules, which gave concrete slurries with similar properties as those of untreated cement slurries. In addition, results of this work show that another viable technique of producing cement agglomerates may be tabletting of dry cement powder with very small amounts of disintegrants. Using plain cement resulted in very hard tablet formation. These tablets gave only a 0.5 wt% loss when shaken in sieves for a period of fifteeen minutes. Addition of 5wt% disintegrant of microcrystalline cellulose gave tablets that immediately dissolved in water as a result of swelling of the disintegrant. Hence there would be no necessity to break these tablets by mechanical means in order to make cement slurries and presence of an inert disintegrant would result in slurries with identical properties as that of untreated cement slurries. Thus tabletting shows very promising results and should be studied further.

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