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Bacillus anthracis, the causative agent of anthrax, has been widely described as a clonal species. Here we report the use of both canonical SNP analysis and whole-genome sequencing to characterize the phylogenetic lineages of B. anthracis from the Netherlands. Eleven strains isolated over a 25-years period (1968–1993) were paired-end sequenced using parallel sequencing technology. Five canSNP groups or lineages, i.e. A.Br.001/002 (n = 6), A.Br.Aust94 (n = 2), A.Br.008/011 (n = 1), A.Br.011/009 (n = 1) and A.Br.Vollum (n = 1) were identified. Comparative analyses, with a focus on SNPs discovery, were carried out using a total of 52 B. anthracis genomes. A phylogeographic “Dutch” cluster within the dominant A.Br.001/002 group was discovered, involving isolates from a single outbreak. Diagnostic SNPs specific to the newly identified sub-groups were developed into high-resolution melting SNP discriminative assays for the purpose of rapid molecular epidemiology. Phylogenetic relationships with strains from other parts of the world are discussed.

Fugitive emissions from Al reduction line roof vents constitute between 75% and 95% of fluoride emissions from an Al smelter, and more than 40% of the roof vent emissions are generated by the pot during periods with opened hoods, mainly during anode change. Boosted suction systems are employed to increase exhaust flow when hoods and tapping doors are moved. The jet induced boosted suction system was developed by Rio Tinto Alcan as a lower cost alternative to dual duct boosted suction systems which require high capital investments. The system boosts pot flow by replacing the existing fixed orifice plates which balance the flow among pots connected to the same dry scrubber by removable pivoting orifice plates. When flow has to be boosted the restriction created by the orifice plate is removed. A jet of low-pressure air is also introduced at the pot outlet inside the ductwork through a nozzle which entrains the surrounding air and provides extra boosted flow. The system was first installed at the AP2X technology Tomago smelter in Australia and scaled up for the AP3X pot technology smelters at the Saint-Jean-de- Maurienne and Aluminium Dunkerque smelters in France, and an industrial demonstration has been carried out at the Alma smelter., Fugitive emissions from Al reduction line roof vents constitute between 75% and 95% of fluoride emissions from an Al smelter, and more than 40% of the roof vent emissions are generated by the pot during periods with opened hoods, mainly during anode change. Boosted suction systems are employed to increase exhaust flow when hoods and tapping doors are moved. The jet induced boosted suction system was developed by Rio Tinto Alcan as a lower cost alternative to dual duct boosted suction systems which require high capital investments. The system boosts pot flow by replacing the existing fixed orifice plates which balance the flow among pots connected to the same dry scrubber by removable pivoting orifice plates. When flow has to be boosted the restriction created by the orifice plate is removed. A jet of low-pressure air is also introduced at the pot outlet inside the ductwork through a nozzle which entrains the surrounding air and provides extra boosted flow. The system was first installed at the AP2X technology Tomago smelter in Australia and scaled up for the AP3X pot technology smelters at the Saint-Jean-de- Maurienne and Aluminium Dunkerque smelters in France, and an industrial demonstration has been carried out at the Alma smelter.

The possibility is discussed of valorising the heat extracted from pot gases to produce fresh water, particularly in areas where water is in scarce supply. A case study is presented based on a hypothetical smelter in a Middle Eastern country with one potline operating at 400 kA and producing 403 000 t Al/y. Two gas treatment centres (GTC) are installed with filters with integrated heat exchangers, and plant fresh water consumption is assumed to be 403 000 m3/y. Pot gas heat typically accounts for more than 30% of the total energy dissipated by the pot and can be estimated based on pot gas flow rate and temperature. A revised equation for the pot gas heat is presented assuming that a heat exchanger is installed upstream of the GTC. Up to 20% of the pot gas heat daily average is recoverable in summer, with a yearly average close to 10%, and this can be increased by reducing ductwork losses, for example by installing the heat exchanger as close as possible to the pot outlet. Energy required for the desalination plant is provided by extracting heat from the pot gas, with water being used in a closed-loop circuit to convey energy from the heat exchanger to the desalination plant. Robust heat exchangers of shell and tube design are used to minimise the risk of scaling and the formation of deposits from the pot gas. Multi-effect distillation is considered to be the most effective desalination technology for the particular application., The possibility is discussed of valorising the heat extracted from pot gases to produce fresh water, particularly in areas where water is in scarce supply. A case study is presented based on a hypothetical smelter in a Middle Eastern country with one potline operating at 400 kA and producing 403 000 t Al/y. Two gas treatment centres (GTC) are installed with filters with integrated heat exchangers, and plant fresh water consumption is assumed to be 403 000 m3/y. Pot gas heat typically accounts for more than 30% of the total energy dissipated by the pot and can be estimated based on pot gas flow rate and temperature. A revised equation for the pot gas heat is presented assuming that a heat exchanger is installed upstream of the GTC. Up to 20% of the pot gas heat daily average is recoverable in summer, with a yearly average close to 10%, and this can be increased by reducing ductwork losses, for example by installing the heat exchanger as close as possible to the pot outlet. Energy required for the desalination plant is provided by extracting heat from the pot gas, with water being used in a closed-loop circuit to convey energy from the heat exchanger to the desalination plant. Robust heat exchangers of shell and tube design are used to minimise the risk of scaling and the formation of deposits from the pot gas. Multi-effect distillation is considered to be the most effective desalination technology for the particular application.