Arrive for 19:00
Wednesday Feb 8, 2017
Entry is free. Members and non-members are welcome.
Waste management is a significant issue and will be exacerbated during the 21st century by urbanization. Waste incineration is an attractive management option; however, hazardous gases are produced as a result. Therefore, incineration plants operate sophisticated flue gas treatment systems to remove the contaminants present within the flue gas prior to emission to the atmosphere. Air pollution control (APC) residues are one the solid by-products produced and are classified as hazardous waste.
This talk will describe the key processes involved in modern incineration and their effects on hazardous by-products such as APC residues. The use of carbonation as a means of stabilizing APC residues allowing use as construction materials is analysed. Three UK based incinerators have provided APC residue samples which have been analysed; the results are evaluated to provide context for the application of carbonation as a method to produce secondary building materials.
Porosity has traditionally been viewed as a defect in ceramic materials, a weak point that can lead to mechanical failure and, therefore, manufacturing processes are often designed to produce ceramics with as little porosity as possible. However, as will be discussed in this talk, intentionally introducing pores can actually be beneficial in terms of the energy harvesting performance of ferroelectric ceramics, which is an important developing technology for self-powered wireless sensor networks. Ferroelectrics are of particular interest due to their excellent piezoelectric and pyroelectric properties.
With the aid of finite element models that take into account the complex poling behaviour of porous ferroelectric materials and advanced processing techniques that enable the fabrication of such structures, we demonstrate how porosity can be a whole lot more than a structural defect. Introducing porosity is shown here to be a novel way to improve the energy harvesting capabilities of a ferroelectric ceramic.
Terrestrial mineral resources ar getting harder to exploit; most of the easy deposits have been already exploited and hence costs are expected to rise. The world's undersea resources are estimated to include 10 billion tonnes of polymetallic nodules with an estimated value of of metals in the seabed globally rated at over $2 trillion per annum. The only problem is knowing where the valuable resources lie and hence prospecting with remotely operated vehicles (ROVs) is an area of increasing developmental interests. Deep sea mining is not without opposition due to the vastly unexplored nature of the earth's sea floor. The science community, especially environmentalists, believes that resources needed for independent scientific assessment at these depths are essentially non-existent. Currently, most commercially available ROVs in an affordable range for small institutions and private individuals range from ca. £ 500 to £ 30 000.