Systematic development of a high bitumen content emulsion : a thesis presented in fulfilment of the requirements for the degree of Master of Technology in Product Development at Massey University

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Massey University
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A product development approach appropriate to a medium sized civil engineering company was developed in this study. The approach was practically demonstrated to the company through the development of a high bitumen content emulsion. Product development processes were reviewed and related to the specific company environment to develop an appropriate six stage process consisting of: Project Start. Pre-development, Laboratory Development, Mid-scale Development, Full-scale Development and Commercialisation. The high bitumen content emulsion product was taken from the Project Start stage through to the Full-scale Development stage. During each of the stages, suitable product development systems were generated to practically implement the process. During the Project Start stage, idea capture systems were created and scoring models were developed to initiate development projects. Avenues to allow greater information collection were demonstrated to the company and a cataloguing tool was developed to assist in the organisation of a technical library useful for product development. During the Pre-development stage, marketing and technical specifications were produced to guide later development. The Laboratory Development stage had three phases: initial design, detailed design and optimisation. Experimental design was demonstrated to the company as an appropriate technique to conduct detailed design for formulated and processed products. A full factorial experimental design with four factors at two levels identified an optimum area which was further explored to produce an optimised high bitumen content emulsion at the Laboratory Development stage. A lack of Mid-scale equipment meant scale-up was conducted on a full-scale level in this study. Two full-scale trials were run; both emulsions were stable when exiting the production mill however the emulsion was unable to tolerate conditions it encountered upon entering the spray tanker. Possible causes as to the observed instability were rapid cooling of emulsion, dilution with water, excessive shearing during circulation, incompatibility with bitumen or the formulation. All of these factors were investigated with no conclusive results. It is recommended to further investigate the composition of bitumen used by Higgins as to its suitability for high bitumen content emulsions. A means to test emulsion application variables on a laboratory or mid-scale level are also recommended in order to investigate and solve the problems. The tailored product development approach and supporting systems developed in this study can be used by the company in future to carry out systematic product development.
Bituminous materials -- Development, Asphalt emulsion mixtures