Doctoral Degrees (Process Engineering)

Uncatalysed steam pretreatment regimes for bagasse and harvest residues in a sugarcane biorefinery

Hamann, Martin Louis (Stellenbosch : Stellenbosch University, 2020-03)

ENGLISH ABSTRACT: Biorefining of sugarcane lignocellulosic wastes, i.e. bagasse and harvest residues, at existing cane sugar mills can diversify product ranges to potentially improve profitability. Bagasse is the fibrous ...

Engineering strategies for enhancement of bio-hydrogen production by phototrophic bacterium Rhodopseudomonas palustris

Du Toit, Jan-Pierre (Stellenbosch : Stellenbosch University, 2021-03)

ENGLISH ABSTRACT: The photosynthetic bacterium Rhodopseudomonas palustris demonstrates an exceptional metabolic diversity and is capable of consuming a wide variety of organic compounds including those toxic to other ...

Improving energy and economic performances of a typical sugarcane factory through energy indicator development, set-point optimization, and optimal sensor placement

Mkwananzi, Thobeka (Stellenbosch : Stellenbosch University, 2021-03)

ENGLISH ABSTRACT: The volatile sugar markets and the recent recognition of bagasse as a key feedstock to produce biofuels and bioproducts have prompted a desire in the sugarcane industry to correct energy inefficiencies ...

Development of integrated processes for the coproduction of inulin, protein, and ethanol from Jerusalem artichoke tubers in a biorefinery

Maumela, Pfariso (Stellenbosch : Stellenbosch University, 2021-03)

ENGLISH ABSTRACT: Biorefining is an attractive approach to simultaneously address food supply, energy security and global warming. Furthermore, biorefining offers a sustainable strategy to utilise biomass, for energy ...

Modelling and sustainability analysis of biorefineries using sugarcane lignocellulose to produce polyethylene, sorbitol, glucaric acid and levulinic acid at existing South African sugar mills

Kapanji, Kutemba Kaina (Stellenbosch : Stellenbosch University, 2021-03)

ENGLISH ABSTRACT: The sugar industry in South Africa and the region has been plagued by factors including the low international sugar prices, reduced cane yields due to climate change and competition from new market entrants ...

Techno-economic and sustainability models for integration of cassava waste-based biorefineries into cassava starch processes based on process simulation and a systems modelling approach

Padi, Richard Kingsley (Stellenbosch : Stellenbosch University, 2021-03)

ENGLISH ABSTRACT: Cassava crop high starch yields, accompanied by its tolerance to drought/low soil nutrients, have increased research attention towards the crop’s adoption as a potential food security and economic empowerment ...

Techno-economic analysis of the valorisation of brewers spent grains: Production of xylitol and xylo-oligosaccharides

Swart, Lukas Johannes (Stellenbosch : Stellenbosch University, 2020-12)

ENGLISH ABSTRACT: Techno-economic analysis of the valorisation of brewers spent grains: Production of xylitol and xylo-oligosaccharides Brewers’ spent grains (BSG) make up to 85% of breweries’ solid waste produced, and ...

Fractionation of agro-waste to producebiopolymers and bioactive compounds for active food packaging

Mugwagwa, Lindleen Runyararo (Stellenbosch : Stellenbosch University, 2020-12)

ENGLISH ABSTRACT: The food packaging industry is faced with a need to find alternative raw materials to replace the non-renewable petroleum-based polymers and active compounds used in developing active food ...

Optimisation of nutrient input to integrated aquaponics systems through mineral supplementation by way of fish feed additives

Guwa, Oyama (Stellenbosch : Stellenbosch University, 2020-12)

ENGLISH ABSTRACT: Aquaponics is an integrated production system with the primary goal of sustainable food production in the form of fish and vegetables. The main challenge in aquaponics is the ...

Oxygen transfer in cell-free and simulated alkane-based bioprocesses : Computational Fluid Dynamics (CFD) simulations and predictive modelling

Gakingo, Godfrey Kabungo (Stellenbosch : Stellenbosch University, 2020-12)

ENGLISH ABSTRACT: Alkane activation using whole-cell biocatalysts is an attractive technology that can be employed in alkane valorisation. However, since metabolically active cells involved in this process require oxygen, ...

The hydrodynamics of supercritical packed countercurrent columns

Franken, Hendrik Hermanus (Stellenbosch : Stellenbosch University., 2020-03)

ENGLISH ABSTRACT: Supercritical fluids are enjoying ever-increasing popularity as a solvent medium for extraction, stripping, absorption and fractionation processes. Although the potential of supercritical fluids as solvents ...

Exergy, techno-economic and exergoeconomic analyses for improving energy efficiency of a typical sugar mill and designing integrated biorefineries

Dogbe, Eunice Sefakor (Stellenbosch : Stellenbosch University., 2020-03)

ENGLISH ABSTRACT: The sugar industry is energy-intensive, consuming about 350–600 kg of steam and 25–32 kWh electricity per ton of sugarcane processed into raw crystalline sugar. Though mostly energy-self-sufficient, ...

Process improvements and techno-economic analyses for the production of short-chain fructose-containing oligosaccharides from sucrose and Jerusalem artichoke tubers

Bedzo, Oscar Koku Kplorm (Stellenbosch : Stellenbosch University., 2020-03)

ENGLISH ABSTRACT: Recent years have seen significant growth in the global market for short-chain fructooligo saccharides (scFOS) and inulooligo saccharides (IOS) due to the rising health ...

Designing and evaluating the technical, economic and environmental performance of an adsorption cooling system operating using bioresources from waste streams of mango processing

Dzigbor, Aaron (Stellenbosch : Stellenbosch University, 2019-12)

ENGLISH ABSTRACT: This study sought to improve the technical performance (coefficient of performance (COP) and specific cooling power (SCP)), environmental impacts and economic viability of employing the adsorption working ...

High pressure phase equilibria of the system CO2 + N-dodecane + 3,7-dimethyl-1-octanol + 1-decanol

Latsky, Carla (Stellenbosch : Stellenbosch University, 2019-12)

ENGLISH ABSTRACT: In the detergent manufacturing industry, the product streams containing the detergent range alcohols (C8-C20) are often contaminated with unreacted alkanes. Due to similarity in the boiling and melting ...

Hydroformylation of post-metathesis product using rhodium-based catalysts

Breckwoldt, Nicholas Claus Carl (Stellenbosch : Stellenbosch University, 2019-12)

ENGLISH ABSTRACT: This study forms part of the overall scope of the RSA Olefins Programme for the upgrading of low-value α-alkene feedstocks to higher value detergent-range products within the South African context. The ...

Techno-economic and life cycle analyses for comparison of biorefinery scenarios for the production of succinic acid, itaconic acid and polyhydroxybutyrate (PHB) from sugarcane lignocelluloses

Nieder-Heitmann, Mieke (Stellenbosch : Stellenbosch University, 2019-04)

ENGLISH ABSTRACT: The pressure on energy resources worldwide combined with the awareness of the major impact industrial processes have on the environment, triggers the development of alternative energy sources and methods ...