Heavy metal music

Heavy metal (or simply metal) is a genre of rock music that developed in the late 1960s and early 1970s, largely in the United Kingdom and United States. With roots in blues rock, psychedelic rock and acid rock, heavy metal bands developed a thick, monumental sound characterized by distorted guitars, extended guitar solos, emphatic beats and loudness. In 1968, three of the genre's most famous pioneers – Led Zeppelin, Black Sabbath and Deep Purple – were founded. Though they came to attract wide audiences, they were often derided by critics. Several American bands modified heavy metal into more accessible forms during the 1970s: the raw, sleazy sound and shock rock of Alice Cooper and Kiss; the blues-rooted rock of Aerosmith; and the flashy guitar leads and party rock of Van Halen. During the mid-1970s, Judas Priest helped spur the genre's evolution by discarding much of its blues influence, while Motörhead introduced a punk rock sensibility and an increasing emphasis on speed. Beg

Estimation des rejets urbains de zinc et de cadmium au moyen d'une analyse de flux de substance. Application à la commune de Lausanne

David Gremaud

This work is focused on the problem of the contamination of surface water and sediments by heavy metals, more particularly by cadmium and zinc, contained in runoff water and wastewater. To bring to light the urban cycle of cadmium and zinc, we have used the methodology of the substance flow analyses (SFA) and have elaborated a model. This model consists of various sources, flows, processes and stocks. The zone of study of this work is the municipality of Lausanne, situated at the edge of the Lake Geneva in Switzerland. This city possesses a bay; the bay of Vidy, which knows an important problem of pollution of sediments. Indeed, the values of concentration in heavy metals of sediments, in particular in cadmium and zinc, are superior to the limit values TEC and PEC (cf. chapter 6). The sewer system is of combined type and of separated type. Waters of the combined system are brought to the STEP of Vidy to be treated. On the other hand, waters of the separated system are sent without treatment to surface water. We have identified several sources of cadmium and zinc as domestic wastewater, car traffic, rail traffic, roofs and sidings of buildings, the dry and wet deposition. We have quantified the sources and coefficients of transfer of our model with data of the literature and hypotheses. We have put these values in SimBox, a program developed by the EAWAG, which allows to model the flows of substance and make analyses of sensibility and variation of the parameters. We have obtained the following results for the municipality of Lausanne. The contributions in sediments are 6.996 kgCd/year and 2961.11 kgZn/year. The contributions in surface water are 2.328 kgCd/year and 987.49 kgZn/year. The major sources of cadmium in surface water and sediments are the street furniture (70%), domestic wastewater (14%), roofs (8%) and sidings (3%). The major sources of zinc in surface water and sediments are the street furniture (24%), sidings (20%), roofs (19%), the tires of vehicles (16%) and domestic wastewater (14%). We have proposed several technical solutions to reduce the contributions of metals in surface water and sediments as the infiltration of runoff water in grounds or their discharge in wastewater (combined sewer), roads cleaning, pretreatment followed by a discharge in surface water. We have talked about the last two examples more specifically; roads cleaning and pretreatment followed by a discharge in surface water. The roads cleaning allows a reduction in sediments of 2.6% for cadmium and 3% for zinc. As for the filtering socks placed in the garbage dumps of roads, the reduction is 29% for cadmium and 15% for zinc.

2009

Substance flow analysis as a tool for urban water management

Nathalie Chèvre Rossi, Luca Rossi

Human activity results in the production of a wide range of pollutants that can enter the water cycle through stormwater or wastewater. Among others, heavy metals are still detected in high concentrations around urban areas and their impact on aquatic organisms is of major concern. In this study, we propose to use a substance flow analysis as a tool for heavy metals management in urban areas. We illustrate the approach with the case of copper in Lausanne, Switzerland. The results show that around 1,500 kg of copper enter the aquatic compartment yearly. This amount contributes to sediment enrichment, which may pose a long-term risk for benthic organisms. The major sources of copper in receiving surface water are roofs and catenaries of trolleybuses. They represent 75% of the total input of copper into the urban water system. Actions to reduce copper pollution should therefore focus on these sources. Substance flow analysis also highlights that copper enters surface water mainly during rain events, i.e., without passing through any treatment procedure. A reduction in pollution could also be achieved by improving stormwater management. In conclusion, the study showed that substance flow analysis is a very effective tool for sustainable urban water management.

IWA Publishing2011

Estimation des rejets urbains de zinc et de cadmium au moyen d'une analyse de flux de substance. Application à la commune de Lausanne

David Gremaud

2009

Estimation des rejets urbains de zinc et de cadmium au moyen d'une analyse de flux de substance. Application à la commune de Lausanne

Substance flow analysis as a tool for urban water management

Development of a selective electrolytic process for the recovery of heavy metals (Cu, Pb, Cd, and Zn) from secondary fly ash

Development of a selective electrolytic process for the recovery of heavy metals (Cu, Pb, Cd, and Zn) from secondary fly ash

Estimation des rejets urbains de zinc et de cadmium au moyen d'une analyse de flux de substance. Application à la commune de Lausanne

Substance flow analysis as a tool for urban water management