Value addition of coal fines and sawdust to briquettes using molasses as a binder

Abstract: In this study, the co-briquetting of coal fines saw dust and molasses as a binder is explored as an option for value addition of the wastes generated in the various industries. The effect of the saw dust concentration and the molasses concentration was investigated through measuring the briquette's calorific value, fixed carbon, compressive strength and shatter index. Addition of Ca(OH)2 was done to effect removal of sulphur from the briquette. Measurements of the briquettes physicochemical properties such as moisture content, ash content and sulphur content were measured using the standard methods. As the saw dust and the molasses concentration increased, the calorific value, fixed carbon and compressive strength increased by 16%, 8% and 50% respectively. Whereas, the shatter index decreased by 146% as the saw dust and the molasses concentration increased in relation to the coal fines. Addition of the saw dust and the molasses are therefore critical in the production of a high quality coal-saw dust-molasses briquette which does not shatter

Resource recovery from municipal waste and bio solids (digestate) through vermicomposting: a waste management initiative

Abstract: In this study, municipal waste and anaerobic digestate (bio solids) were co-vermicomposted in a bid to properly manage waste at disposal sites. Municipal waste and bio solids in the ratio 2:1 were vermicomposted in a vermireactor for 45 days. Process parameters such as moisture, temperature and pH as well as the nutrient composition in terms of nitrogen, phosphorous and potassium (NPK) content of the vermicompost were closely monitored. Approximately 250 Eisenia Foetida, a species of the red worms was used as the vermicomposting inoculants. After the 45 days, a rich vermicompost with an NPK composition of 6.18%, 3.27% and 8.26% respectively. The optimum conditions for producing this vermicompost were moisture content>27%, temperature >18.6% and neutral pH. An addition of the bio solids to municipal waste during vermicomposting adds value to the nutritional composition of the vermicompost

Biological treatment of distillery wastewater by application of the vermifiltration technology

Abstract: In this study distillery wastewater was treated using the vermifiltration technology in a bid to reduce downstream contamination by the effluent. 10kg of Eisenia Fetida earthworms were used as the vermifiltration media in a 0.5m x 0.5m x 0.3m vermifiltration bed over a 40 hour period cycle. The distillery effluent physicochemical parameters which included pH, total Kjeldahl nitrogen (TKN), biological oxygen demand (BOD), total dissolved solids (TDS), total suspended solids (TSS) and the chemical oxygen demand (COD) were measured every 5 days. The vermicompost which was produced as a result of the vermifiltration process’s nitrogen, phosphorous and potassium composition was also determined. The distillery effluent pH changed from acidic to neutral whilst a decrease of 94.9% was observed for the TKN, 91.1% for the BOD, 91.9% for the TDS, 92.4% for the TSS and 89.4% for the COD upon treatment with vermifiltration. The vermicompost, a by-product of the vermifiltration process had a nitrogen, phosphorous and potassium composition of 1.87%, 0.87% and 0.66% respectively

Enhanced Biogas Generation from Co-Digestion of Sewage Sludge and Kitchen Bio-Waste

In this study kitchen waste and sewage sludge were co-digested anaerobically to produce biogas with the aid of engineering granules to enhance biogas production. Co-digestion was conducted for mesophilic and thermophilic conditions in a 20L bio digester for a period of 30 days. Hycura was inoculated to enhance biogas production. The co-digestion resulted in significant degrease of the total volatile solids and chemical oxygen demand of the bio-waste by >75%. Mesophilic conditions favored high quality biogas production with methane content as high as 74%. Inoculation with Hycura hindered H2S production which enhanced the quality of the biogas and makes it easier for upgradin

Bio ethanol from sewage sludge: A bio fuel alternative

Abstract: In this study, the potential to fully exploit sewage sludge as a raw material for bio ethanol a source of bio fuel is investigated. Sewage sludge hydrolysate was first made by introducing Bacillus flexus in order for saccharification to take place before fermenting to bio ethanol using yeast. The hydrolysate was then prepared for fermentation by introducing 10 g/L of peptone, 2 g/L of KH2PO4 and 1 g/L of MgSO4. Af- terwards, fermentation was allowed to take place at varying pH (4.0e7.0), temperature (15e45 o C), in- cubation time (10e70 h) and yeast concentrations (2e10% (v/v). Bio ethanol concentrations were characterized through spectrophotometry and its physicochemical properties analyzed by standard methods. Pearson Correlations Coefficients in MATLAB 13.0 were used to determine the coefficients of interaction between the various parameters in bio ethanol production at 95% confidence interval. Highest bio ethanol yields of greater than 40 mL/L were achieved at an incubation period of 10 days, with an operating temperature of 30 o C and pH of 6.5 with yeast concentration of 6% wt. The interactions between incubation temperature and pH had the best interaction coefficient of 0.9759 being achieved for optimal bio ethanol yield. The bio ethanol produced had a flash point of 19.2 o C, pour point of 4.9 o C, cloud point of 20 o C and viscosity of 1.30 cP

Municipal solid waste data quality on artificial neural network performance

Abstract: Short and long-term municipal solid waste (MSW) management requires adequate planning. Understanding the relationship among variables that affect MSW generation and predicting MSW based on them is needed for an effective planning. Methodologies to forecast MSW are numerous and have been implemented at different level of data granularity. Lack of data in many African cities and countries has hampered effective waste management plan. The lack of data has mainly been attributed to insufficient budget and lack of capacity to implement such management structure. In this study, we investigated the impact of data quality on forecasting efficiency using advanced prediction techniques. It was observed that the quality of waste related data variables determines the extent of model reliability and prediction accuracy

A Study on the Market Potential of Biomass-Based Micro Gas Turbines in SubSaharan Africa

Selection and peer-review under responsibility of the scientific committee of the 13th Int. Conf. on Applied Energy (ICAE2021).Biomass can be used as an alternative fuel in micro gas turbines to produce electricity, heat and/ or cooling. This is an affordable carbon-neutral renewable energy source which is widely available in most African countries. In this project the main aim is to gather information and data to evaluate the feasibility and the market potential of this technology in three sub-Saharan African countries. This includes data about the energy market, information on feedstock availability in different regions, statistics on the electricity grid, the demand profiles of different consumers, as well as insight on the national policies and regulation. The information is used to help understand the needs of the energy market in the partner countries and the potential of the proposed technology.Global Challenges Research Fund (GCRF), provided by Research England

A review on factors affecting municipal solid waste generation

Abstract: Municipal solid waste (MSW) management is not a one-off planning, it is a dynamic evolution and planning has to cater for it. The quantity of MSW generated and composition form the basis for planning and management of MSW. However, for an effective MSW reduction policy to be implemented, generated quantity of MSW is not sufficient alone for policy implementation but more of the variables affecting the generation rate and composition are critical. Without an in-depth understanding of these variables, waste reduction policies may be ineffective and unsuccessful. In this study, we reviewed the impact of these factors on MSW. A case of the City of Johannesburg (CoJ) was studied. Population and gross domestic product (GDP) are the two compelling factors affecting MSW generation. The waste generation per capita is influenced by income level. High income group generate on average 1.91 kg/capita/day, middle income group generates 1.01 kg/capita/day and low income group 0.92 kg/capita/day. This put the CoJ total waste generated at an average of 1.83 million ton/year