Production, evaluation and testing of bioethanol from matooke peels species as an alternative fuel for spark ignition engine: a case study of Uganda.

Doctoral Degree. University of KwaZulu-Natal, Durban.Conversion of new lignocellulose biomass (LCB) waste to energy is an innovative technique for waste valorization and management which reduces environmental pollutions and offers socioeconomic benefits. This has made the LCB to be significant due to its novel behavior towards bioenergy. The aims of this study is to characterize the biomass, evaluate and produce the bioethanol fuels from unique LCB which is matooke peels species, and examined the emissions and combustion effects of low content rates of bioethanol blends with gasoline in a modernized spark-ignition engine. The matooke peels species such as Mbwazirume and Nakyinyika biomass peels, which are pretreated and untreated were characterized to identify its use in bioenergy production. This characterization of biomass was carried out using various analyses such as proximate and ultimate analysis, thermo-gravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), atomic absorption spectroscopy (AAS), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometer (EDXS). Experimental findings reveal that the pretreated Mbwazirume biomass exhibits excellent solid fuel properties when compared to untreated Mbwazirume, pretreated and untreated Nakyinyika biomass peels. Bioethanol fuels were produced from Mbwazirume and Nakyinyika biomass peels through a fermentation process using Saccharomyces cerevisiae and analyzed using ANOVA. The study also optimized production variables and determined the models for separate hydrolysis and fermentation (SHF). The properties of the bioethanol were measured according to relevant ASTM standards and compared with the standard ethanol and gasoline. Mbwazirume biomass shows higher bioethanol yields and excellent fuel properties, this serve as a fuel of choice for further experiment. The bioethanol ratios were blend with gasoline at (E0, E5, E10, and E15) used in the development of further experiments on engine and combustion performance, and exhaust emissions test in a modernized TD201 four-stroke petrol engine. The results obtained were computed, modeled, evaluated and analyzed. Results show that the small differences in properties between bioethanol-gasoline blends are enough to create a significant change in the combustion system. These effects lead to behavioral mechanisms which are not easy to analyze or understand, sometimes make it difficult to identify the fundamentals of how blend ratios affect emissions and performance

Bioethanol production from different Matooke peels species: A surprising source for alternative fuel

Conversion of agro-industrial wastes to energy is an innovative technique for waste valorization and management which reduces exhaust emissions and offers socioeconomic benefits. The goal of this paper is to investigate the feasibility of producing bioethanol from a renewable and sustainable energy resource which is matooke species peels through a fermentation process using Saccharomyces cerevisiae. The properties of the bioethanol were measured according to relevant ASTM standards and compared, and analyzed by gas chromatography. The results shows that the bioethanol yield for the two samples through fermentation process was found to be 71.54 g/L for the Mbwazirume variety and 70.57 g/L for the Nakyinyika variety, and the selected parameters have a strong correlation with the ethanol yield, as analyzed by ANOVA. In conclusion, matooke bioethanol properties are within the acceptable range of standard ethanol and gasoline. These matooke bioethanol can be used in the development of further experiments on performance and exhaust emissions test in spark-ignition (SI) engines. Keywords: Agro-industrial waste, Exhaust emissions, Bioethanol, Matooke peels, Spark-ignition (SI) engine

Quantification and characterization of solid waste generated within Mulago national referral hospital, Uganda, East Africa

Hospital waste is a special category of waste that is quite detrimental as it may contain infectious and contaminated substances thus posing serious threats to the environment and public health. The knowledge of quantities and characteristics of hospital waste, helps in proper management. This study aimed at waste quantification, characterization, and assessment of the general waste management patterns at Mulago referral hospital, Uganda. The experiment was carried out for 30 consecutive days and solid waste generated within 24 hours were collected from different departments of the Mulago hospital in designated containers, sorted and weighed then grouped into general waste and clinical waste. The study established that general waste comprises 72% while clinical waste is 28% of the total waste generated in the facility. The average solid waste generation rate was found to be at 111.4kg per day with wards producing the highest quantities, followed by operating theatres, kitchen, public areas, laundry, and administration. Using the individualized Rapid Assessment Tool (I-RAT), it was found that Mulago hospital's authorities are aware of policies surrounding the handling and disposal methods of waste and gaps were observed in compliance. The average solid waste sorting compliance in the hospital was found very low, 37.4%, with the highest compliance in operating theatres at 62.8%, followed by the administration 51.7%, kitchen 32%, wards 27.3%, public areas 25.6%, and laundry 25%. The analysis of the discharged liquid waste revealed that Lead, Nitrate, COD, and BOD concentrations were beyond the permissible limits. Therefore, we recommend commitment on compliance with policies and legislation measures to safeguard the workers and environment. Technically, we recommend a bio-chemical pre-treatment of wastewater for the abatement of the pollutants prior to discharging it into the environment. Also, to minimize waste mixing and spillage at the waste generation points as a result of inappropriate bins, we recommend a combined 0.062 m3 capacity containers for general waste and 0.024 m3 for clinical waste in all hospital units

Investigating the influence of plastic waste oils and acetone blends on diesel engine combustion, pollutants, morphological and size particles: Dehalogenation and catalytic pyrolysis of plastic waste

Most research into the treats of plastic wastes have concentrated mainly on single-exposure pathways or products. These practices fail to acknowledge that the complications of carbon particles from engines are produced not only by diesel but by any plastic oils due to the vast amount of contaminants. With the potential to significantly weaken the impact of contaminants, the present study investigates the effects of dehalogenation and catalytic pyrolysis on plastic waste, as well as the risks associated with plastic oil blends on diesel engine. Different types of washing were conducted to effectively dehalogenate plastic waste. After pretreatment, odor compounds were analyzed using GC–MS. Subsequently, various types of pretreated plastic samples underwent catalytic pyrolysis with a 5:1 ratio of HDPE to Al2O3·2SiO2·2H2O. Differences in physico-chemical properties and hydrocarbon compounds of oils were determined. Experiments were performed using different fuel blends in a diesel engine under steady-state conditions, and their effects on combustion, emissions, morphology, and size particles were analyzed. The results show that sample B exhibited a lower toxicity level of 1,3-butadiene compared to other samples, while acetone and terpenes represented the second and third-highest emission levels in flakes, respectively. Sample C started to degrade at low temperatures (<300 °C) due to carbon addition from ethyl acetate solvent into the tertiary carbon chain of the flakes. DAP3 fuel achieved a higher reaction due to its degree of unsaturation and lower viscosity, resulting in the formation of smaller fuel droplets at high injection pressure and heat release rate (HRR). Higher emission levels were observed by DAP1 and D100, exceeding the Euro 5/6 standard limits. However, DAP3 fuel resulted in an average reduction of ∼17.14% and 21.86% in CO and smoke emissions, respectively, accompanied by a slight decrease in NOx and HC levels. Conversely, there were inconsistencies in the emission results observed with DAP2. Compared to D100, both DAP1 and DAP2 exhibited a significant accumulation and coarse particles in the PM10 forms at a peak of ∼83 nm. Whereas the DAP3 showed a smaller mobility Dp with a low nucleation particle peak, which was prone to absorb the unburned HC soot and later change to accumulation mode particles

Diesel Spray: Development of Spray in Diesel Engine

Research and development in the internal combustion engine (ICE) has been growing progressively. Issues such as air pollution, fuel cost, and market competitiveness have driven the automotive industry to develop and manufacture automobiles that meet new regulation and customers’ needs. The diesel engine has some advantages over the gasoline or spark ignition engine, including higher engine efficiency, greater power output, as well as reliability. Since the early stage of the diesel engine’s development phase, the quest to obtain better atomization, proper fuel supply, and accurate timing control, have triggered numerous innovations. In the last two decades, owing to the development of optical technology, the visualization of spray atomization has been made possible using visual diagnostics techniques. This advancement has greatly improved research in spray evolution. Yet, a more comprehensive understanding related to these aspects has not yet been agreed upon. Diesel spray, in particular, is considered a complicated phenomenon to observe because of its high-speed, high pressure, as well as its high temperature working condition. Nevertheless, several mechanisms have been successfully explained using fundamental studies, providing several suggestions in the area, such as liquid atomization and two-phase spray flow. There are still many aspects that have not yet been agreed upon. This paper comprehensively reviews the current status of theoretical diesel spray and modelling, including some important numerical and experimental aspects

Diesel Spray: Development of Spray in Diesel Engine

Research and development in the internal combustion engine (ICE) has been growing progressively. Issues such as air pollution, fuel cost, and market competitiveness have driven the automotive industry to develop and manufacture automobiles that meet new regulation and customers&rsquo; needs. The diesel engine has some advantages over the gasoline or spark ignition engine, including higher engine efficiency, greater power output, as well as reliability. Since the early stage of the diesel engine&rsquo;s development phase, the quest to obtain better atomization, proper fuel supply, and accurate timing control, have triggered numerous innovations. In the last two decades, owing to the development of optical technology, the visualization of spray atomization has been made possible using visual diagnostics techniques. This advancement has greatly improved research in spray evolution. Yet, a more comprehensive understanding related to these aspects has not yet been agreed upon. Diesel spray, in particular, is considered a complicated phenomenon to observe because of its high-speed, high pressure, as well as its high temperature working condition. Nevertheless, several mechanisms have been successfully explained using fundamental studies, providing several suggestions in the area, such as liquid atomization and two-phase spray flow. There are still many aspects that have not yet been agreed upon. This paper comprehensively reviews the current status of theoretical diesel spray and modelling, including some important numerical and experimental aspects