The ever increase in energy consumption across the world is booming significantly. This has led to fossil fuels to dwindle. The increase in population and fuel-based machinery acts as an extra burden since the traditional fuels is non-renewable and nonsustainable. In addition, these fuel-based energy sources damage the environment. For such reasons, the industries are looking for alternative sources of energy, mainly focusing on renewable energy such as solar, wind, hydro, tidal and geothermal energy. Another less common source of renewable energy is Biofuel. What distinguishes Biofuel from other sustainable energy sources is that Biomass can be converted directly in a liquid form which is usually used for transportation desires. The most popular types of Biofuels are Biodiesel and alcohol called Ethanol. Biodiesel possesses similar properties to fossil fuel diesel but is non-toxic, produces a lower level of pollutant emissions compared to fossil fuels and is considered biodegradable. Thus, Biodiesel production and research is gaining paramount importance and has become one of the fastest growing alternative fuels across the globe. Namely, the U.S. biodiesel consumption increased from nearly 0.25 billion gallons in 2010 to nearly 2.00 billion gallons in 2017 (U.S. EIA). On the other hand, since biodiesel is a clean fuel made from vegetable oils, fats, or greases its production also contributes to the recycling of these waste oils and greases. The subject of this contribution is the design of a domestic machine transforming WCO to Biodiesel. This multidisciplinary topic is presented from the chemical and mechanical standpoints. The former emphasizes on carrying the most adequate chemical process to end up with the correct biodiesel blend. Whereas the latter deals with the actual design of storage and reactor tanks with an optimization of the mixing process through modeling and simulating mixing using ANSYS Fluent for different impellers design.

Dry shot blast generated during stainless steel production contains high content of valued metals such as iron chromium and nickel. These metals are in the form of oxides and it can be used as a raw material in iron and steel. This work aims to study the feasibility of metals recovery from dry shot blast by smelting reduction process. Smelting reduction of dry shot blast by using coking coal as reductant was conducted in an induction furnace. The effect of metallurgical parameters e.g. stoichiometry ratio of reductant per oxygen containing in dry shot blast, CaO/SiO2 of slag forming and CaF2 in slag, on %recovery of metal product was investigated. The results based on this study showed that the weight of metal product increases with increased the amount of coke to about 1.5 of stoichiometric molar ratio. Increasing of coke above this amount leads to decrease %recovery of metal product. Moreover, the weight of metal product is increased when the ratio of CaO/SiO2 in slag decreased from 2 to 1. The chemical composition of the metal product is in the range of commercial grade and it can be used as raw materials to produce steel and cast iron alloy.

This research aims to study the feasibility of nickel recovery from spent electroplating solution via hydrometallurgy and electro-chemical treatment. The spent nickel-plating solution obtained as an industrial waste was found to contain nickel of 89.4 g/l, which was still in high quantity sufficient for prospective recovery. In this research, precipitation of nickel from the spent electro plating solution was first carried out to separate other unwanted impurities. The remained nickel precipitate was then leached by using 1 M or 2 M H2SO4 for 24 h. at a solid/liquid ratio of 100 g/l. The leached solution was then adjusted to obtain pH 2 prior to electrowinning. It was found that the maximum weight of nickel cathode is 5.07 g or at 90.7% recovery of 97.46% purity can be achieved in a condition using 1 M H2SO4 and electrical potential 3.7 V.

In developing countries, the biodegradable component of municipal solid waste is typically composed of 40-60% kitchen waste. Composting is a globally accepted technology for clean and sustainable management of organic waste. This study attempts to assess three domestic composting systems, Kamba (clay pots), rotary drum, and bin composting. Technical and economic features of the systems were also discussed and compared. During the composting process greenhouse gases are generated, mechanisms to reduce the greenhouse emissions are noted. Composting and Bokashi systems are compared in terms of process mechanisms, the quality of end products, operation and maintenance process. The domestic composting process reduces the pressure on the collection and transportation components of municipal solid waste management. This review provides an insight into the development of strategies for municipal solid waste management at the household level.

In African countries, post-consumer plastic packaging has become a challenge in terms of marine pollution by dumping of plastics; global warming gas generation by incineration of plastics technologies sustainability. Some cities with more than one million inhabitants still have only small landfills, while the size of the population involves huge amounts of waste. In the case of Madagascar, municipalities collect postconsumer plastic waste composed of different types of dirty polymers with other wastes. Among the various types of recycling management approaches, the reuse of waste and recycled plastic material in the construction sector is considered an ideal method for disposing of plastic waste. This present work aims to assess the construction material using plastic packing waste as a replacement of cement in a concrete and evaluate the mechanical and physical properties of the product. Thus, the methodology is easy to implement and appropriate to the local context in Madagascar.