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A distribution channel decision is very important. A foreign chemical additive manufacturer wishes to develop an indirect distribution channel into the China refinery and petrochemical market. The selection of a favorable distributor to work with in the China market will involve a number of complex decisions by the manufacturer. Developing the criteria and strategy to screen and select a China distributor is studied in this research. A mutual understanding and cooperation between the manufacturer and distributor to define explicit roles, expectations, and responsibilities is necessary. Three critical definitions include: 1) The contract terms and conditions, especially with regard to time period, contract termination, and consideration of efforts during contract life once contract is terminated; 2) Commitment of the manufacturer to fully support distributor once distribution contract is awarded; 3) The distributor¡¦s opportunities to expand distribution rights in return for strong performance. Motivating the owners and employees of the independent organizations in a distribution chain requires great effort. Methods of motivating a distributor organization will be reserved for a more advanced study in the future.

Nonlinearities exist in all process control systems. The use of linear control techniques is valid only in a narrow range of operation. Therefore, in this thesis, multivariable nonlinear control techniques are considered. The target process is the single effect evaporative process of the liquor burning unit in Alcoa's alumina refinery in Kwinana and the proposed triple effects unit in the Wagerup refinery. Two types of nonlinear control strategies using differential geometry were studied, namely, the input output linearization (Kravaris and Soroush, 1990) and the input state linearization (Hunt et al, 1983a). The research has successfully demonstrated the superiority and simplicity of the nonlinear controller through simulations and plant implementations. An integrated software package using MAPLE V.3 as the computing environment was developed to automate the solution algorithms and to graphically simulate the closed loop dynamics of different processes using the two nonlinear control strategies.The issue of robustness of the nonlinear controller was addressed by developing a procedure called uncertainty vector adjustment. The effectiveness of the new strategy was successfully demonstrated on the simulated liquor burning process. Furthermore, the stability of the adjustment technique was proved and its theoretical bounds were established using Lyapunov function analysis.A comparative study of geometric nonlinear filter and extended Kalman filter was conducted to reduce the requirement of full state feedback necessary for nonlinear control using either input output linearization or input state linearization. The simulation of the single effect evaporation unit of the liquor burning process showed that the geometric nonlinear filter is superior to the extended Kalman filter in terms of nonlinear tracking performances.The plant trials of the input output linearization ++ / in Alcoa's Kwinana alumina refinery demonstrated the practicability and feasibility of implementing nonlinear control in an industrial setting and also fostered a closer gap between academia and industry. The trials established guidelines for implementing a global linearizing controller on site, including conversion of the relevant constraints and the output of an industrial proportional and integral controller to the equivalent proportional and integral action required by the nonlinear controller. The results showed that the performance of the nonlinear controller was better than the current linear controller on site in terms of responsiveness and resistance to disturbances. Hence, the nonlinear control strategy enables the process to settle faster.All in all, efforts have been made in this thesis to minimise the use of abstract mathematical language and, in some cases, simplify the language so that nonlinear control theory can be understood by a wider range of audience, especially industrial practitioners. It is hoped that the insights provided in the dissertation will encourage more industrial implementations of nonlinear controllers and forge more interaction to close the widening gap between academic and industrial practice in process control.Keywords: nonlinear control, differential geometry, symbolic algebra, evaporator process, uncertainty vector adjustment, geometric nonlinear filter.

Saudi Aramco is investigating the potential use of oxidized disulfide oil (ODSO), a refinery waste, as a solvent to replace water in zeolite preparation for the implication in industrial processes such as Fluidized Catalytic Cracking (FCC) aiming to increase propylene production. Utilizing ODSO helps Saudi Aramco reduces its processing costs, creates a value for this solvent and reduces the zeolite synthesis cost. One major concern is the effect ODSO may have on the catalytic performance of the prepared zeolites. This study investigates the catalytic cracking of 1-hexene and 2-methyl-2-butene (2M2B) at various WHSV and temperatures over ZSM-5 catalysts prepared from gels with SiO$_2$/Al$_2$O$_3$ ratios (SAR) of 50 and 25 and various ODSO/water substitutions. Six ODSO-based ZSM-5 catalysts were prepared and characterized in terms of acidity, morphology, and textural properties. The impact of catalyst composition and properties on conversion and selectivity is examined and compared to commercial ZSM-5 catalysts with similar SAR (CBV2314 and CBV5524G). At 477 h$^{-1}$ WHSV, ODSO-based catalysts achieved 80% 1-hexene conversion with 53-60% propylene selectivity, outperforming commercial catalysts (52%). However, 2M2B cracking exhibits slower reaction rates and more oligomerization cracking, resulting in lower conversion (46-61%) and propylene selectivity (22-29%). Notably, MAR- 2-3 (30% ODSO, 50 SAR gel) shows the best performance among the ODSO catalysts in terms of stability and selectivity, with results comparable to the commercial catalysts. We noticed, on the other hand, that ODSO-based catalysts possess larger crystals and higher acid site density compared to the commercial catalysts leading, generally, to a decreased stability. These findings enhance understanding of waste-based zeolites in catalytic cracking processes and guide the development of improved ODSO-based catalysts for petrochemical applications.

This research project will investigate the potential business case and technical feasibility of using nuclear generated heat in a crude oil refinery located some distance away. The key design element is an energy transportation mechanism that doesn’t compromise the safety, licensing or operability of the nuclear plant. In a crude oil refinery processing heat is generated by combusting fuels that are generally sellable products. The inherent safety features and high output temperature of a HTGR make it an appropriate replacement heat source for such a processing plant. An opportunity thus exists to replace the refinery hydrocarbon fuel usage with nuclear energy thereby improving refinery profitability. Three alternate proposed were generated. Alt 1: Generation of steam at HTGR, piped to the refinery to replace current supply. Alt 2: Closed loop reversible methanation reaction delivering potential chemical energy to the refinery which is released to the process in heat exchangers. Alt 3: Hydrogen production from water splitting at the HTGR, piped to the refinery and combusted in boilers or used for hydrotreating diesel. Utilizing data from refinery plant historian and journals, a basic engineering study assessed technical feasibility thereof. An economic model for the 2 most promising alternates was set up using quotations and factored data and evaluated against the existing refinery situation. A consistently increasing crude price was assumed. Alternates 1, 2 and 3 proved technically feasible and delivered 86 MW, 59 MW and 48MW to the refinery respectively. Generating steam at the HTGR (Alt 1) demonstrated an attractive business case, strengthened by co-locating the nuclear plant at the refinery. It is therefore concluded that using a HTGR for process heat in a petrochemical plant such as a refinery is techno-economically practical and demands further consideration. If future carbon emission legislation is promulgated this proposal will be key component of the solution. / MIng (Nuclear Engineering), North-West University, Potchefstroom Campus, 2014

In this study, the implementation of membrane technology at Anglo Platinum’s base metals refinery to separate acid from metal containing solutions was investigated. The refinery includes a circuit known as the “sulphur removal section”, where the acid in the spent nickel electrolyte is neutralized with caustic soda to remove the excess sulphur from the overall process. Reagent costs associated with acid neutralisation, result in high operating expenditures. An alternative process route is required to improve efficiencies and stay competitive. Nanofiltration was investigated to separate acid from nickel, with the aim of recovering the acid and thereby reducing the need for expensive neutralisation. The objectives of this study were twofold: (1) investigate and simulate the current base metals refinery, and (2) use the understanding and process know-how to investigate the use of nanofiltration by modifying the simulation to include for this technology. The modified process simulation was then used to evaluate the type of membrane required for technical viability. The process investigation of the refinery proceeded with literature studies done on base metals recovery process, chemical reactions and design criteria applicable to the process. A simulation of the base metals refinery was undertaken in Aspen Plus using the information established in the process investigation. The simulation provided insight into the operational issues across the flowsheet, and identified key areas of the process which were sensitive to parameter changes in the sulphur removal section. Areas which were impacted were the electrowinning and copper removal section. The simulation therefore provided a useful tool to predict process variabilities as a result of plant modifications. The investigation into nanofiltration found that it can successfully be used to separate metal ions from acid, subject to the constraints of metal ion concentrations. Pre-treatment of the nickel spent electrolyte was required to remove most of the sodium sulphate in solution, since this can cause fouling and thereby degrade membrane performance. For this reason, a cold crystallization process was introduced for the removal of sodium sulphate. However the sodium removal process caused the sodium sulphate levels in the electrowinning feed to drop below 100 g/l. Therefore minor modifications had to be made to the electrowinning pre-treatment process. The nanofiltration process itself consisted of a series of six nanofiltration stages with dilution of the interstage feed to allow the system to operate below osmotic pressure and wash out all the acid from the system. The modified simulation including the new sulphur removal circuit (nanofiltration process) was completed by integrating the current base metals refinery simulation with the new sulphur removal process, thereby providing a tool where different membrane characteristics could be varied to enable the performance of the overall process to be evaluated. The membrane parameters varied were the nickel rejection, the sodium rejection and the acid rejection. The simulation predicted that each of the cases which varied the mentioned parameters would be technically feasible, although not necessarily economically feasible. The process was most sensitive to acid rejection. The key variables were the amount of water used for dilution, and the membrane size. An exponential distribution was present for the sensitivity of membrane size versus acid rejection; thus realistic membrane sizes can only be achieved if the acid rejection is -100% or less. Furthermore, the addition of dilution water results in the nickel being washed out with the acid, despite nickel rejection being in the region of 99.5%. This demonstrates the importance of the membrane nickel rejection to be as high as possible. / MIng (Chemical Engineering), North-West University, Potchefstroom Campus, 2014

This research project will investigate the potential business case and technical feasibility of using nuclear generated heat in a crude oil refinery located some distance away. The key design element is an energy transportation mechanism that doesn’t compromise the safety, licensing or operability of the nuclear plant. In a crude oil refinery processing heat is generated by combusting fuels that are generally sellable products. The inherent safety features and high output temperature of a HTGR make it an appropriate replacement heat source for such a processing plant. An opportunity thus exists to replace the refinery hydrocarbon fuel usage with nuclear energy thereby improving refinery profitability. Three alternate proposed were generated. Alt 1: Generation of steam at HTGR, piped to the refinery to replace current supply. Alt 2: Closed loop reversible methanation reaction delivering potential chemical energy to the refinery which is released to the process in heat exchangers. Alt 3: Hydrogen production from water splitting at the HTGR, piped to the refinery and combusted in boilers or used for hydrotreating diesel. Utilizing data from refinery plant historian and journals, a basic engineering study assessed technical feasibility thereof. An economic model for the 2 most promising alternates was set up using quotations and factored data and evaluated against the existing refinery situation. A consistently increasing crude price was assumed. Alternates 1, 2 and 3 proved technically feasible and delivered 86 MW, 59 MW and 48MW to the refinery respectively. Generating steam at the HTGR (Alt 1) demonstrated an attractive business case, strengthened by co-locating the nuclear plant at the refinery. It is therefore concluded that using a HTGR for process heat in a petrochemical plant such as a refinery is techno-economically practical and demands further consideration. If future carbon emission legislation is promulgated this proposal will be key component of the solution. / MIng (Nuclear Engineering), North-West University, Potchefstroom Campus, 2014

In this study, the implementation of membrane technology at Anglo Platinum’s base metals refinery to separate acid from metal containing solutions was investigated. The refinery includes a circuit known as the “sulphur removal section”, where the acid in the spent nickel electrolyte is neutralized with caustic soda to remove the excess sulphur from the overall process. Reagent costs associated with acid neutralisation, result in high operating expenditures. An alternative process route is required to improve efficiencies and stay competitive. Nanofiltration was investigated to separate acid from nickel, with the aim of recovering the acid and thereby reducing the need for expensive neutralisation. The objectives of this study were twofold: (1) investigate and simulate the current base metals refinery, and (2) use the understanding and process know-how to investigate the use of nanofiltration by modifying the simulation to include for this technology. The modified process simulation was then used to evaluate the type of membrane required for technical viability. The process investigation of the refinery proceeded with literature studies done on base metals recovery process, chemical reactions and design criteria applicable to the process. A simulation of the base metals refinery was undertaken in Aspen Plus using the information established in the process investigation. The simulation provided insight into the operational issues across the flowsheet, and identified key areas of the process which were sensitive to parameter changes in the sulphur removal section. Areas which were impacted were the electrowinning and copper removal section. The simulation therefore provided a useful tool to predict process variabilities as a result of plant modifications. The investigation into nanofiltration found that it can successfully be used to separate metal ions from acid, subject to the constraints of metal ion concentrations. Pre-treatment of the nickel spent electrolyte was required to remove most of the sodium sulphate in solution, since this can cause fouling and thereby degrade membrane performance. For this reason, a cold crystallization process was introduced for the removal of sodium sulphate. However the sodium removal process caused the sodium sulphate levels in the electrowinning feed to drop below 100 g/l. Therefore minor modifications had to be made to the electrowinning pre-treatment process. The nanofiltration process itself consisted of a series of six nanofiltration stages with dilution of the interstage feed to allow the system to operate below osmotic pressure and wash out all the acid from the system. The modified simulation including the new sulphur removal circuit (nanofiltration process) was completed by integrating the current base metals refinery simulation with the new sulphur removal process, thereby providing a tool where different membrane characteristics could be varied to enable the performance of the overall process to be evaluated. The membrane parameters varied were the nickel rejection, the sodium rejection and the acid rejection. The simulation predicted that each of the cases which varied the mentioned parameters would be technically feasible, although not necessarily economically feasible. The process was most sensitive to acid rejection. The key variables were the amount of water used for dilution, and the membrane size. An exponential distribution was present for the sensitivity of membrane size versus acid rejection; thus realistic membrane sizes can only be achieved if the acid rejection is -100% or less. Furthermore, the addition of dilution water results in the nickel being washed out with the acid, despite nickel rejection being in the region of 99.5%. This demonstrates the importance of the membrane nickel rejection to be as high as possible. / MIng (Chemical Engineering), North-West University, Potchefstroom Campus, 2014

Många företag och industrier arbetar idag ständigt med att utveckla mindre miljöbelastande sätt att arbeta på, det beror på hårdare lagar och regler än tidigare angående utsläpp till miljön. Företag inventerar mycket resurser på ny forskning och ta fram nya metoder, allt för att bidra till en hållbar utveckling. St1 är ett av de företagen som vill vara med i arbetet för en hållbar utveckling och främst av förnybara bränslen. St1 har utvecklat en ny metod för framställning av etanol utav restråvaror från livsmedelsindustrin. Det bildas även drank som är en biprodukt som man kör ut till lantbruk för att använda som djurfoder eller vid produktion av biogas. Metoden benämns som Etanolix och den nya anläggningen på St1 Refinery AB är den senaste som fått namnet Etanolix 2.0. Syftet med rapporten är att visa hur integrering kan göras med en ny anläggning tillsammas med en redan befintlig och hur man kan ta till vara på outnyttjade resurser. I rapporten beskrivs de olika hjälpsystem som är integrerade med Etanolix 2.0 som processvatten, kvävgas samt ånga och kondensat. Det beskrivs också hur första året med Etanolix 2.0 i drift har gått och vad som varit utmaningarna vid uppstarten. Slutsatsen vi kom fram till är att Etanolix metoden bidrar till en hållbar utveckling och steget närmare att skapa framtida förnybara bränslen. Projekt Etanolix 2.0 är fortfarande i uppstartningsfasen och behöver ytterligare utveckling innan optimal produktion av etanol kan ske.