m echanical Engineering g roup

Mr Ilyas Omar omari@cput.ac.za

Mr Selbourne Makhomo makhomos@cput.ac.za

The group’s energy activities are currently focused on combustion stack height determination and diesel engine performance testing when running on biodiesel and biofuel blends.

Highlights for 2014

Work continued on the diesel engine testing programme, running varying blends of biofuels and biodiesels. One related paper was presented at the ICUE2014 Conference, and a poster was prepared for the CPUT Postgraduate Conference.

Research focuses on fuel and exhaust back pressure. Biodiesel and biofuel have shown that they contain qualities required as alternative fuels. The SABS has draft specifications on biofuels which address some of the issues highlighted in this work. It is suggested that further work in terms of long term on-road engine testing could be explored in the next phases of the study.

Model development for the determination of combustion stack heights is being done in collaboration with the Western Cape Department of Environmental Affairs and Development Planning. Two students are currently working on this.

A tool for computing standardised stack heights which can assist with improved air quality management and improved air pollution dispersion is being designed. Such a tool would enable local authorities to take into account a number of relevant factors in determining the height of a chimney. This would streamline methods for the installation of industrial boilers and determining the height of stacks across the province.

Project sunshine

The Western Cape could soon become the manufacturing hub of evacuated tube solar water heaters. These devices are the newest form of solar water heaters and are becoming a global leader in the market for cost-effective heating alternatives.

CPUT and Trihelix International Business Developers in China are collaborating on Project Sunshine, an initiative that could lead to the development of a solar water heater manufacturing plant in the Western Cape. CPUT is involved with research and development of the devices, and has set up a testing facility at the Mechanical engineering building. It is managed by lecturer Mr fareed Ismail and involves several undergraduate and postgraduate engineering students. “We are currently conducting tests to determine the viability of the evacuated tube solar water heaters in our climate,” said Mr Ismail.

The devices are made up of a several panels and interlocking tubes designed to trap the sun’s radiation and heat water pushed through the tubes. The heated water is collected in a geyser. operational Manager at Trihelix, Mr Cedrick Hendriks, said Project Sunshine holds huge benefits for the local community as it could lead to the creation of up to 300 new job opportunities at the plant, as well as a further 4000 in related sectors.

Nanomaterials g roup

Prof Greyling received a Water Research Commission grant (Grant no. WRC K5/2386) of R1.25 million for a 2014/2015 project titled Nanoparticles for the treatment of industrial scale effluents – Particularly the removal of organic contaminants from textile effluents using nano-TiO2

In 2014, the ultrasmall -FeOOH nanorod developed by Prof Fester and Dr Chowdhury was combined with TiO2 in a heterojunction structure, and the photocatalytic activities were investigated under simulated solar irradiation. This unique photocatalyst was able to degrade model dyes such as methyl orange. The catalyst showed promising application in photocatalytic treatment of real textile waste water, as 67% TOC was removed only after two hours of irradiation.

The continuous hydrothermal synthesis (CHS) laboratory scale pilot plant that was commissioned in 2013 was used this year to develop a process for manufacturing TiO2 and to determine critical process conditions for producing TiO2 consisting of various polymorphs. The locally manufactured TiO2 will be evaluated as a replacement for commercially available imported TiO2 nanoparticles in the photocatalytic degradation of textile waste water.