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30 Jahre Vegetationsentwicklung schleswig-holsteinischer Moore - Untersuchungen an Dauerbeobachtungsflächen

Auf 22 Dauerbeobachtungsflächen in drei Mooren Schleswig-Holsteins wurde von 1989 bis 2019 im Abstand von 10 Jahren die Vegetation erfasst. In zahlreichen Handtorfstichen konnten die Ausbreitung von Mittlerem Torfmoos (Sphagnum magellanicum) und die Entwicklung der Hochmoorbultengesellschaft über eine Zeitspanne von 30 Jahren sowie eine Oligo- und Ombrotrophierung (Verringerung der Nähstoffversorgung und Ernährung aus dem Niederschlagswasser) der Standorte beobachtet werden. Stoppen der Binnenentwässerung, Überstau, Abschieben und Birkenentnahmen haben zur Revitalisierung schützenswerter Lebensräume geführt. Im Fockbeker Moor wurden beim Erico-Sphagnetum typicum in den letzten 10 Jahren eine Abnahme der Schlenken (tiefer gelegene Standorte im Mikrorelief von Mooren), eine stärkere Bildung von Bulten (höhere Standorte) und eine Zunahme der Heidekräuter festgestellt. Auf einer nackten Torffläche sind nach 23 Jahren Torfmoose eingewandert. Die Sukzession der überstauten Fläche im Fockbeker Moor begann mit Torfmoosrasen, Eriophorum-Arten und Heidekräutern nach 10 Jahren und zeigt heute Bewaldung mit Moor-Birke (Betula pubescens). In fast allen Dauerflächen ist eine Zunahme der Phanerogamendeckung und der Artenzahlen festzustellen. Seit 10 Jahren ist eine Ausbreitung von Weißem Schnabelried (Rhynchospora alba) und Besenheide (Calluna vulgaris) im Wittenseer und Fockbeker Moor und von Moorlilie (Narthecium ossifragum) im Owschlager Moor zu verzeichnen. Die Veränderung der Artenzusammensetzung und die Ombrotrophierung werden dargestellt und vor dem Hintergrund durchgeführter Revitalisierungsmaßnahmen, autogener Sukzession, Stickstoffbelastung und Klimawandel interpretiert. Es werden Empfehlungen für künftig stärker zu berücksichtigende Maßnahmen in Hinblick auf den Klimawandel gegeben.

Resilienz naturnaher Moore im Klimawandel – Fallbeispiele aus dem Biosphärenreservat Schorfheide-Chorin

Der Klimawandel wirkt auf die wenigen noch wachsenden Moore ein, so dass die Frage besteht, inwieweit die Resilienz dieser autochthonen Ökosysteme in all ihrer Vielfalt gestützt werden kann. Zur Beantwortung werden Dauerbeobachtungsreihen von weitgehend ungestörten Mooren aus dem Biosphärenreservat Schorfheide-Chorin (Brandenburg) ausgewertet. Diese werden mit den Ergebnissen einer Erfolgskontrolle wiedervernässter Waldmoore in Kontext gesetzt. Zur Einschätzung der Moorzustände wird ein neu entwickeltes Indikatorensystem zur Bewertung moorspezifischer Biodiversität angewendet. Es wird zudem eine Abschätzung der Treibhausgasemissionen nach der Treibhaus-Gas-Emissions-Standort-Typen(GEST)-Methodik vorgenommen und die potenzielle Torfneubildung betrachtet. Die Analysen zeigen, dass das Puffervermögen wachsender Moore im Untersuchungsraum noch intakt ist und Störungen ohne Systemwechsel überwunden werden. Die Vernässungsmaßnahmen waren durchweg erfolgreich und haben zu einer messbaren Revitalisierung geführt. Es wird auf die dringende Notwendigkeit hingewiesen, heute alle noch weitestgehend naturnahen Moore in ihrem Wasserhaushalt bestmöglich zu stabilisieren, um sie als wichtige Glieder der autochthonen Biodiversität mit allen ihren positiven Landschaftsfunktionen zu erhalten.

Evaluierung vorhandener Bewertungsansätze und Entwicklung eines Konzeptes zur integrierten Wirkungsbewertung prioritärer Schadstoffe über alle Pfade auf der Grundlage der Bioverfügbarkeit

Mit dem Bundes-Bodenschutzgesetz (BBodSchG) wurde 1998 in der Bundesrepublik Deutschland für den nachhaltigen Schutz der Böden die wesentliche fachliche und juristische Grundlage geschaffen, um eine effektive Altlastensanierung und eine Revitalisierung von kontaminierten Standorten und deren Wiedereingliederung in den Wirtschaftskreislauf zu ermöglichen. Eine Aufgabe des BBodSchG ist die nachhaltige Sicherung und Wiederherstellung der Funktionen der Böden. Bei Altlasten liegt in der Regel eine Beeinträchtigung dieser Funktionen vor. Veröffentlicht in Texte | 59/2011.

Weiterentwicklung von Abwasserabgabe und Wasserentnahmeentgelten zu einer umfassenden Wassernutzungsabgabe

Der Einsatz von ökonomischen Instrumenten in der Gewässerschutzpolitik hat in Gestalt der bundesrechtlichen Abwasserabgabe und der verschiedenen landesrechtlichen Wasserentnahmeentgelte in eutschland bereits eine längere Tradition. Ebenso lang ist freilich die Geschichte der kritischen Begleitung dieser Instrumente in Wissenschaft, Praxis und Politik. Forderungen nach einer Revitalisierung der als konzeptionell unzulänglich empfundenen Lenkungsinstrumente stehen dabei wiederholten Rufen nach ihrer Abschaffung gegenüber, da sich mangels Lenkungswirkung die Bedeutung in reiner Fiskalzwecksetzung erschöpfe. Veröffentlicht in Texte | 67/2011.

Markt für Gold

technologyComment of gold mine operation and refining (SE): OPEN PIT MINING: The ore is mined in four steps: drilling, blasting, loading and hauling. In the case of a surface mine, a pattern of holes is drilled in the pit and filled with explosives. The explosives are detonated in order to break up the ground so large shovels or front-end loaders can load it into haul trucks. ORE AND WASTE HAULAGE: The haul trucks transport the ore to various areas for processing. The grade and type of ore determine the processing method used. Higher-grade ores are taken to a mill. Lower grade ores are taken to leach pads. Some ores may be stockpiled for later processing. HEAP LEACHING: The ore is crushed or placed directly on lined leach pads where a dilute cyanide solution is applied to the surface of the heap. The solution percolates down through the ore, where it leaches the gold and flows to a central collection location. The solution is recovered in this closed system. The pregnant leach solution is fed to electrowinning cells and undergoes the same steps as described below from Electro-winning. ORE PROCESSING: Milling: The ore is fed into a series of grinding mills where steel balls grind the ore to a fine slurry or powder. Oxidization and leaching: Some types of ore require further processing before gold is recovered. In this case, the slurry is pressure-oxidized in an autoclave before going to the leaching tanks or a dry powder is fed through a roaster in which it is oxidized using heat before being sent to the leaching tanks as a slurry. The slurry is thickened and runs through a series of leaching tanks. The gold in the slurry adheres to carbon in the tanks. Stripping: The carbon is then moved into a stripping vessel where the gold is removed from the carbon by pumping a hot caustic solution through the carbon. The carbon is later recycled. Electro-winning: The gold-bearing solution is pumped through electro-winning cells or through a zinc precipitation circuit where the gold is recovered from the solution. Smelting: The gold is then melted in a furnace at about 1’064°C and poured into moulds, creating doré bars. Doré bars are unrefined gold bullion bars containing between 60% and 95% gold. References: Newmont (2004) How gold is mined. Newmont. Retrieved from http://www.newmont.com/en/gold/howmined/index.asp technologyComment of gold production (US): OPEN PIT MINING: The ore is mined in four steps: drilling, blasting, loading and hauling. In the case of a surface mine, a pattern of holes is drilled in the pit and filled with explosives. The explosives are detonated in order to break up the ground so large shovels or front-end loaders can load it into haul trucks. UNDERGROUND MINING: Some ore bodies are more economically mined underground. In this case, a tunnel called an adit or a shaft is dug into the earth. Sort tunnels leading from the adit or shaft, called stopes, are dug to access the ore. The surface containing the ore, called a face, is drilled and loaded with explosives. Following blasting, the broken ore is loaded onto electric trucks and taken to the surface. Once mining is completed in a particular stope, it is backfilled with a cement compound. BENEFICIATION: Bald Mountain Mines: The ore treatment method is based on conventional heap leaching technology followed by carbon absorption. The loaded carbon is stripped and refined in the newly commissioned refinery on site. Water is supplied by wells located on the mine property. Grid power was brought to Bald Mountain Mine in 1996. For this purpose, one 27-kilometre 69 KVA power line was constructed from the Alligator Ridge Mine substation to the grid. Golden Sunlight Mines: The ore treatment plant is based on conventional carbon-in-pulp technology, with the addition of a Sand Tailings Retreatment (STR) gold recovery plant to recover gold that would otherwise be lost to tailings. The STR circuit removes the heavier gold bearing pyrite from the sand portion of the tailings by gravity separation. The gold is refined into doré at the mine. Tailing from the mill is discharged to an impoundment area where the solids are allowed to settle so the water can be reused. A cyanide recovery/destruction process was commissioned in 1998. It eliminates the hazard posed to wildlife at the tailings impoundment by lowering cyanide concentrations below 20 mg/l. Fresh water for ore processing, dust suppression, and fire control is supplied from the Jefferson Slough, which is an old natural channel of the Jefferson River. Ore processing also uses water pumped from the tailings impoundment. Pit water is treated in a facility located in the mill complex prior to disposal or for use in dust control. Drinking water is made available by filtering fresh water through an on-site treatment plant. Electric power is provided from a substation at the south property boundary. North-Western Energy supplies electricity the substation. Small diesel generators are used for emergency lighting. A natural gas pipeline supplies gas for heating buildings, a crusher, air scrubber, boiler, carbon reactivation kiln, and refining furnaces. Cortez Mine: Three different metallurgical processes are employed for the recovery of gold. The process used for a particular ore is determined based on grade and metallurgical character of that ore. Lower grade oxide ore is heap leached, while higher-grade non-refractory ore is treated in a conventional mill using cyanidation and a carbon-in-leach (“CIL”) process. When carbonaceous ore is processed by Barrick, it is first dry ground, and then oxidized in a circulating fluid bed roaster, followed by CIL recovery. In 2002 a new leach pad and process plant was commissioned; this plant is capable of processing 164 million tonnes of heap leach ore over the life of the asset. Heap leach ore production is hauled directly to heap leach pads for gold recovery. Water for process use is supplied from the open pit dewatering system. Approximately 90 litres per second of the pit dewatering volume is diverted for plant use. Electric power is supplied by Sierra Pacific Power Company (“SPPC”) through a 73 kilometre, 120 kV transmission line. A long-term agreement is in place with SPPC to provide power through the regulated power system. The average power requirement of the mine is about 160 GWh/year. REFINING: Wohlwill electrolysis. It is assumed that the gold doré-bars from both mines undergo the treatment of Wohlwill electrolysis. This process uses an electrolyte containing 2.5 mol/l of HCl and 2 mol/l of HAuCl4 acid. Electrolysis is carried out with agitation at 65 – 75 °C. The raw gold is intro-duced as cast anode plates. The cathodes, on which the pure gold is deposited, were for many years made of fine gold of 0.25 mm thickness. These have now largely been replaced by sheet titanium or tantalum cathodes, from which the thick layer of fine gold can be peeled off. In a typical electrolysis cell, gold anodes weighing 12 kg and having dimensions 280×230×12 mm (0.138 m2 surface) are used. Opposite to them are conductively connected cathode plates, arranged by two or three on a support rail. One cell normally contains five or six cathode units and four or five anodes. The maximum cell voltage [V] is 1.5 V and the maximum anodic current density [A] 1500 A/m2. The South African Rand refinery gives a specific gold production rate of 0.2 kg per hour Wohlwill electrolysis. Assuming a current efficiency of 95% the energy consumption is [V] x [A] / 0.2 [kg/h] = 1.63 kWh per kg gold refined. No emissions are assumed because of the purity and the high value of the material processed. The resulting sludge contains the PGM present in the electric scrap and is sold for further processing. OTHER MINES: Information about the technology used in the remaining mines is described in the References. WATER EMISSIONS: Water effluents are discharged into rivers. References: Auerswald D. A. and Radcliffe P. H. (2005) Process technology development at Rand Refinery. In: Minerals Engineering, 18(8), pp. 748-753, Online-Version under: http://dx.doi.org/10.1016/j.mineng.2005.03.011. Newmont (2004) How gold is mined. Newmont. Retrieved from http://www.newmont.com/en/gold/howmined/index.asp Renner H., Schlamp G., Hollmann D., Lüschow H. M., Rothaut J., Knödler A., Hecht C., Schlott M., Drieselmann R., Peter C. and Schiele R. (2002) Gold, Gold Alloys, and Gold Compounds. In: Ullmann's Encyclopedia of Industrial Chemistry. Online version, posting date: September 15, 2000 Edition. Wiley-Interscience, Online-Version under: http://dx.doi.org/10.1002/14356007.a12_ 499. Barrick (2006b) Environment: Performance Tables from http://www.barrick. com/Default.aspx?SectionID=8906c4bd-4ee4-4f15-bf1b-565e357c01e1& LanguageId=1 Newmont (2005b) Now & Beyond: Sustainability Reports. Newmont Mining Corporation. Retrieved from http://www.newmont.com/en/social/reporting/ index.asp technologyComment of gold production (CA): OPEN PIT MINING: The ore is mined in four steps: drilling, blasting, loading and hauling. In the case of a surface mine, a pattern of holes is drilled in the pit and filled with explosives. The explosives are detonated in order to break up the ground so large shovels or front-end loaders can load it into haul trucks. UNDERGROUND MINING: Some ore bodies are more economically mined underground. In this case, a tunnel called an adit or a shaft is dug into the earth. Sort tunnels leading from the adit or shaft, called stopes, are dug to access the ore. The surface containing the ore, called a face, is drilled and loaded with explosives. Following blasting, the broken ore is loaded onto electric trucks and taken to the surface. Once mining is completed in a particular stope, it is backfilled with a cement compound. ORE AND WASTE HAULAGE: The haul trucks transport the ore to various areas for processing. The grade and type of ore determine the processing method used. Higher-grade ores are taken to a mill. Lower grade ores are taken to leach pads. Some ores may be stockpiled for later processing. BENEFICIATION: In the Porcupine Mines, gold is recovered using a combination of gravity concentration, milling and cyanidation techniques. The milling process consists of primary crushing, secondary crushing, rod/ball mill grinding, gravity concentration, cyanide leaching, carbon-in-pulp gold recovery, stripping, electrowinning and refining. In the Campbell Mine, the ore from the mine, after crushing and grinding, is processed by gravity separation, flotation, pressure oxidation, cyanidation and carbon-in-pulp process followed by electro-winning and gold refining to doré on site. The Musselwhite Mine uses gravity separation, carbon in pulp, electro¬winning and gold refining to doré on site. REFINING: Wohlwill electrolysis. It is assumed that the gold doré-bars from both mines undergo the treatment of Wohlwill electrolysis. This process uses an electrolyte containing 2.5 mol/l of HCl and 2 mol/l of HAuCl4 acid. Electrolysis is carried out with agitation at 65 – 75 °C. The raw gold is intro-duced as cast anode plates. The cathodes, on which the pure gold is deposited, were for many years made of fine gold of 0.25 mm thickness. These have now largely been replaced by sheet titanium or tantalum cathodes, from which the thick layer of fine gold can be peeled off. In a typical electrolysis cell, gold anodes weighing 12 kg and having dimensions 280×230×12 mm (0.138 m2 surface) are used. Opposite to them are conductively connected cathode plates, arranged by two or three on a support rail. One cell normally contains five or six cathode units and four or five anodes. The maximum cell voltage [V] is 1.5 V and the maximum anodic current density [A] 1500 A/m2. The South African Rand refinery gives a specific gold production rate of 0.2 kg per hour Wohlwill electrolysis. Assuming a current efficiency of 95% the energy consumption is [V] x [A] / 0.2 [kg/h] = 1.63 kWh per kg gold refined. No emissions are assumed because of the purity and the high value of the material processed. The resulting sludge contains the PGM present in the electric scrap and is sold for further processing. WATER EMISSIONS: Effluents are discharged into the ocean. REFERENCES: Newmont (2004) How gold is mined. Newmont. Retrieved from http://www.newmont.com/en/gold/howmined/index.asp Renner H., Schlamp G., Hollmann D., Lüschow H. M., Rothaut J., Knödler A., Hecht C., Schlott M., Drieselmann R., Peter C. and Schiele R. (2002) Gold, Gold Alloys, and Gold Compounds. In: Ullmann's Encyclopedia of Industrial Chemistry. Online version, posting date: September 15, 2000 Edition. Wiley-Interscience, Online-Version under: http://dx.doi.org/10.1002/14356007.a12_ 499. Auerswald D. A. and Radcliffe P. H. (2005) Process technology development at Rand Refinery. In: Minerals Engineering, 18(8), pp. 748-753, Online-Version under: http://dx.doi.org/10.1016/j.mineng.2005.03.011. technologyComment of gold production (AU): OPEN PIT MINING: The ore is mined in four steps: drilling, blasting, loading and hauling. In the case of a surface mine, a pattern of holes is drilled in the pit and filled with explosives. The explosives are detonated in order to break up the ground so large shovels or front-end loaders can load it into haul trucks. UNDERGROUND MINING: Some ore bodies are more economically mined underground. In this case, a tunnel called an adit or a shaft is dug into the earth. Sort tunnels leading from the adit or shaft, called stopes, are dug to access the ore. The surface containing the ore, called a face, is drilled and loaded with explosives. Following blasting, the broken ore is loaded onto electric trucks and taken to the surface. Once mining is completed in a particular stope, it is backfilled with a cement compound. ORE AND WASTE HAULAGE: The haul trucks transport the ore to various areas for processing. The grade and type of ore determine the processing method used. Higher-grade ores are taken to a mill. Lower grade ores are taken to leach pads. Some ores may be stockpiled for later processing. LEACHING: The ore is crushed or placed directly on lined leach pads where a dilute cyanide solution is applied to the surface of the heap. The solution percolates down through the ore, where it leaches the gold and flows to a central collection location. The solution is recovered in this closed system. The pregnant leach solution is fed to electrowinning cells and undergoes the same steps as described below from Electro-winning. ORE PROCESSING: Milling: The ore is fed into a series of grinding mills where steel balls grind the ore to a fine slurry or powder. Oxidization and leaching: Some types of ore require further processing before gold is recovered. In this case, the slurry is pressure-oxidized in an autoclave before going to the leaching tanks or a dry powder is fed through a roaster in which it is oxidized using heat before being sent to the leaching tanks as a slurry. The slurry is thickened and runs through a series of leaching tanks. The gold in the slurry adheres to carbon in the tanks. Stripping: The carbon is then moved into a stripping vessel where the gold is removed from the carbon by pumping a hot caustic solution through the carbon. The carbon is later recycled. Electro-winning: The gold-bearing solution is pumped through electro-winning cells or through a zinc precipitation circuit where the gold is recovered from the solution. Smelting: The gold is then melted in a furnace at about 1’064°C and poured into moulds, creating doré bars. Doré bars are unrefined gold bullion bars containing between 60% and 95% gold. REFINING: Wohlwill electrolysis. It is assumed that the gold doré-bars from both mines undergo the treatment of Wohlwill electrolysis. This process uses an electrolyte containing 2.5 mol/l of HCl and 2 mol/l of HAuCl4 acid. Electrolysis is carried out with agitation at 65 – 75 °C. The raw gold is intro-duced as cast anode plates. The cathodes, on which the pure gold is deposited, were for many years made of fine gold of 0.25 mm thickness. These have now largely been replaced by sheet titanium or tantalum cathodes, from which the thick layer of fine gold can be peeled off. In a typical electrolysis cell, gold anodes weighing 12 kg and having dimensions 280×230×12 mm (0.138 m2 surface) are used. Opposite to them are conductively connected cathode plates, arranged by two or three on a support rail. One cell normally contains five or six cathode units and four or five anodes. The maximum cell voltage [V] is 1.5 V and the maximum anodic current density [A] 1500 A/m2. The South African Rand refinery gives a specific gold production rate of 0.2 kg per hour Wohlwill electrolysis. Assuming a current efficiency of 95% the energy consumption is [V] x [A] / 0.2 [kg/h] = 1.63 kWh per kg gold refined. No emissions are assumed because of the purity and the high value of the material processed. The resulting sludge contains the PGM present in the electric scrap and is sold for further processing. WATER EMISSIONS: Water effluents are discharged into rivers. REFERENCES: Newmont (2004) How gold is mined. Newmont. Retrieved from http://www.newmont.com/en/gold/howmined/index.asp Renner H., Schlamp G., Hollmann D., Lüschow H. M., Rothaut J., Knödler A., Hecht C., Schlott M., Drieselmann R., Peter C. and Schiele R. (2002) Gold, Gold Alloys, and Gold Compounds. In: Ullmann's Encyclopedia of Industrial Chemistry. Online version, posting date: September 15, 2000 Edition. Wiley-Interscience, Online-Version under: http://dx.doi.org/10.1002/14356007.a12_ 499. Auerswald D. A. and Radcliffe P. H. (2005) Process technology development at Rand Refinery. In: Minerals Engineering, 18(8), pp. 748-753, Online-Version under: http://dx.doi.org/10.1016/j.mineng.2005.03.011. technologyComment of gold production (TZ): The mining of ore from open pit and underground mines is considered. technologyComment of gold refinery operation (ZA): REFINING: The refinery, which provides a same day refining service, employs the widely used Miller Chlorination Process to upgrade the gold bullion it receives from mines to at least 99.50% fine gold, the minimum standard required for gold sold on the world bullion markets. It also employs the world’s leading silver refining technology. To further refine gold and silver to 99.99% the cost-effective once-through Wohlwill electrolytic refining process is used. MILLER CHLORINATION PROCESS: This is a pyrometallurgical process whereby gold dore is heated in furnace crucibles. The process is able to separate gold from impurities by using chlorine gas which is added to the crucibles once the gold is molten. Chlorine gas does not react with gold but will combine with silver and base metals to form chlorides. Once the chlorides have formed they float to the surface as slag or escape as volatile gases. The surface melt and the fumes containing the impurities are collected and further refined to extract the gold and silver. This process can take up to 90 minutes produces gold which is at least 99.5% pure with silver being the main remaining component. This gold can be cast into bars as 99.5% gold purity meets the minimum London Good Delivery. However some customers such as jewellers and other industrial end users require gold that is almost 100% pure, so further refining is necessary. In this case, gold using the Miller process is cast into anodes which are then sent to an electrolytic plant. The final product is 99.99% pure gold sponge that can then be melted to produce various end products suited to the needs of the customer. WOHLWILL PROCESS - The electrolytic method of gold refining was first developed by Dr. Emil Wohlwill of Norddeutsche Affinerie in Hamburg in 1874. Dr. Wohlwill’s process is based on the solubility of gold but the insolubility of silver in an electrolyte solution of gold chloride (AuCl3) in hydrochloric acid. Figure below provide the overview of the refining process (source Rand Refinery Brochure) imageUrlTagReplace7f46a8e2-2df0-4cf4-99a8-2878640be562 Emissions includes also HCl to air: 7.48e-03 Calculated from rand refinery scrubber and baghouse emmission values Metal concentrators, Emmision report 2016 http://www.environmentalconsultants.co.za/wp-content/uploads/2016/11/Appendix-D1.pdf technologyComment of gold refinery operation (RoW): REFINING: The refinery, which provides a same day refining service, employs the widely used Miller Chlorination Process to upgrade the gold bullion it receives from mines to at least 99.50% fine gold, the minimum standard required for gold sold on the world bullion markets. It also employs the world’s leading silver refining technology. To further refine gold and silver to 99.99% the cost-effective once-through Wohlwill electrolytic refining process is used. MILLER CHLORINATION PROCESS: This is a pyrometallurgical process whereby gold dore is heated in furnace crucibles. The process is able to separate gold from impurities by using chlorine gas which is added to the crucibles once the gold is molten. Chlorine gas does not react with gold but will combine with silver and base metals to form chlorides. Once the chlorides have formed they float to the surface as slag or escape as volatile gases. The surface melt and the fumes containing the impurities are collected and further refined to extract the gold and silver. This process can take up to 90 minutes produces gold which is at least 99.5% pure with silver being the main remaining component. This gold can be cast into bars as 99.5% gold purity meets the minimum London Good Delivery. However some customers such as jewellers and other industrial end users require gold that is almost 100% pure, so further refining is necessary. In this case, gold using the Miller process is cast into anodes which are then sent to an electrolytic plant. The final product is 99.99% pure gold sponge that can then be melted to produce various end products suited to the needs of the customer. WOHLWILL PROCESS - The electrolytic method of gold refining was first developed by Dr. Emil Wohlwill of Norddeutsche Affinerie in Hamburg in 1874. Dr. Wohlwill’s process is based on the solubility of gold but the insolubility of silver in an electrolyte solution of gold chloride (AuCl3) in hydrochloric acid. Figure below provide the overview of the refining process (source Rand Refinery Brochure) imageUrlTagReplace7f46a8e2-2df0-4cf4-99a8-2878640be562 Emissions includes also HCl to air: 7.48e-03 Calculated from rand refinery scrubber and baghouse emmission values Metal concentrators, Emmision report 2016 http://www.environmentalconsultants.co.za/wp-content/uploads/2016/11/Appendix-D1.pdf technologyComment of gold-silver mine operation with refinery (PG): OPEN PIT MINING: The ore is mined in four steps: drilling, blasting, loading and hauling. In the case of a surface mine, a pattern of holes is drilled in the pit and filled with explosives. The explosives are detonated in order to break up the ground so large shovels or front-end loaders can load it into haul trucks. ORE AND WASTE HAULAGE: The haul trucks transport the ore to various areas for processing. The grade and type of ore determine the processing method used. Higher-grade ores are taken to a mill. Lower grade ores are taken to leach pads. Some ores may be stockpiled for later processing. HEAP LEACHING: The recovery processes of the Misima Mine are cyanide leach and carbon in pulp (CIP). The ore is crushed or placed directly on lined leach pads where a dilute cyanide solution is applied to the surface of the heap. The solution percolates down through the ore, where it leaches the gold and flows to a central collection location. The solution is recovered in this closed system. The pregnant leach solution is fed to electrowinning cells and undergoes the same steps as described below from Electro-winning. ORE PROCESSING: Milling: The ore is fed into a series of grinding mills where steel balls grind the ore to a fine slurry or powder. Oxidization and leaching: The recovery process in the Porgera Mine is pressure oxidation and cyanide leach. The slurry is pressure-oxidized in an autoclave before going to the leaching tanks or a dry powder is fed through a roaster in which it is oxidized using heat before being sent to the leaching tanks as a slurry. The slurry is thickened and runs through a series of leaching tanks. The gold in the slurry adheres to carbon in the tanks. Stripping: The carbon is then moved into a stripping vessel where the gold is removed from the carbon by pumping a hot caustic solution through the carbon. The carbon is later recycled. Electro-winning: The gold-bearing solution is pumped through electro-winning cells or through a zinc precipitation circuit where the gold is recovered from the solution. Smelting: The gold is then melted in a furnace at about 1’064°C and poured into moulds, creating doré bars. Doré bars are unrefined gold bullion bars containing between 60% and 95% gold. WATER SUPPLY: For Misima Mine, process water is supplied from pit dewatering bores and in-pit water. Potable water is sourced from boreholes in the coastal limestone. For Porgera Mine, the main water supply of the mine is the Waile Creek Dam, located approximately 7 kilometres from the mine. The reservoir has a capacity of approximately 717, 000 m3 of water. Water for the grinding circuit is also extracted from Kogai Creek, which is located adjacent to the grinding circuit. The mine operates four water treatment plants for potable water and five sewage treatment plants. ENERGY SUPPLY: For Misima Mine, electricity is produced by the mine on site or with own power generators, from diesel and heavy fuel oil. For Porgera Mine, electricity is produced by the mine on site. Assumed with Mobius / Wohlwill electrolysis. Porgera's principal source of power is supplied by a 73-kilometre transmission line from the gas fired and PJV-owned Hides Power Station. The station has a total output of 62 megawatts (“MW”). A back up diesel power station is located at the mine and has an output of 13MW. The average power requirement of the mine is about 60 MW. For both Misima and Porgera Mines, an 18 MW diesel fired power station supplies electrical power. Diesel was used in the station due to the unavailability of previously supplied heavy fuel oil. technologyComment of gold-silver mine operation with refinery (CA-QC): One of the modelled mine is an open-pit mine and the two others are underground. technologyComment of gold-silver mine operation with refinery (RoW): The mining of ore from open pit mines is considered. technologyComment of platinum group metal, extraction and refinery operations (ZA): The ores from the different ore bodies are processed in concentrators where a PGM concentrate is produced with a tailing by product. The PGM base metal concentrate product from the different concentrators processing the different ores are blended during the smelting phase to balance the sulphur content in the final matte product. Smelter operators also carry out toll smelting from third part concentrators. The smelter product is send to the Base metal refinery where the PGMs are separated from the Base Metals. Precious metal refinery is carried out on PGM concentrate from the Base metal refinery to split the PGMs into individual metal products. Water analyses measurements for Anglo Platinum obtained from literature (Slatter et.al, 2009). Mudd, G., 2010. Platinum group metals: a unique case study in the sustainability of mineral resources, in: The 4th International Platinum Conference, Platinum in Transition “Boom or Bust.” Water share between MC and EC from Mudd (2010). Mudd, G., 2010. Platinum group metals: a unique case study in the sustainability of mineral resources, in: The 4th International Platinum Conference, Platinum in Transition “Boom or Bust.” technologyComment of primary zinc production from concentrate (RoW): The technological representativeness of this dataset is considered to be high as smelting methods for zinc are consistent in all regions. Refined zinc produced pyro-metallurgically represents less than 5% of global zinc production and less than 2% of this dataset. Electrometallurgical Smelting The main unit processes for electrometallurgical zinc smelting are roasting, leaching, purification, electrolysis, and melting. In both electrometallurgical and pyro-metallurgical zinc production routes, the first step is to remove the sulfur from the concentrate. Roasting or sintering achieves this. The concentrate is heated in a furnace with operating temperature above 900 °C (exothermic, autogenous process) to convert the zinc sulfide to calcine (zinc oxide). Simultaneously, sulfur reacts with oxygen to produce sulfur dioxide, which is subsequently converted to sulfuric acid in acid plants, usually located with zinc-smelting facilities. During the leaching process, the calcine is dissolved in dilute sulfuric acid solution (re-circulated back from the electrolysis cells) to produce aqueous zinc sulfate solution. The iron impurities dissolve as well and are precipitated out as jarosite or goethite in the presence of calcine and possibly ammonia. Jarosite and goethite are usually disposed of in tailing ponds. Adding zinc dust to the zinc sulfate solution facilitates purification. The purification of leachate leads to precipitation of cadmium, copper, and cobalt as metals. In electrolysis, the purified solution is electrolyzed between lead alloy anodes and aluminum cathodes. The high-purity zinc deposited on aluminum cathodes is stripped off, dried, melted, and cast into SHG zinc ingots (99.99 % zinc). Pyro-metallurgical Smelting The pyro-metallurgical smelting process is based on the reduction of zinc and lead oxides into metal with carbon in an imperial smelting furnace. The sinter, along with pre-heated coke, is charged from the top of the furnace and injected from below with pre-heated air. This ensures that temperature in the center of the furnace remains in the range of 1000-1500 °C. The coke is converted to carbon monoxide, and zinc and lead oxides are reduced to metallic zinc and lead. The liquid lead bullion is collected at the bottom of the furnace along with other metal impurities (copper, silver, and gold). Zinc in vapor form is collected from the top of the furnace along with other gases. Zinc vapor is then condensed into liquid zinc. The lead and cadmium impurities in zinc bullion are removed through a distillation process. The imperial smelting process is an energy-intensive process and produces zinc of lower purity than the electrometallurgical process. technologyComment of processing of anode slime from electrorefining of copper, anode (GLO): Based on typical current technology. Anode slime treatment by pressure leaching and top blown rotary converter. Production of Silver by Möbius Electrolysis, Gold by Wohlwill electrolysis, copper telluride cement and crude selenium to further processing. technologyComment of silver-gold mine operation with refinery (CL): OPEN PIT MINING: The ore is mined in four steps: drilling, blasting, loading and hauling. In the case of a surface mine, a pattern of holes is drilled in the pit and filled with explosives. The explosives are detonated in order to break up the ground so large shovels or front-end loaders can load it into haul trucks. BENEFICIATION: The processing plant consists of primary crushing, a pre-crushing circuit, (semi autogenous ball mill crushing) grinding, leaching, filtering and washing, Merrill-Crowe plant and doré refinery. The Merrill-Crowe metal recovery circuit is better than a carbon-in-pulp system for the high-grade silver material. Tailings are filtered to recover excess water as well as residual cyanide and metals. A dry tailings disposal system was preferred to a conventional wet tailings impoundment because of site-specific environmental considerations. technologyComment of silver-gold mine operation with refinery (RoW): Refinement is estimated with electrolysis-data. technologyComment of treatment of precious metal from electronics scrap, in anode slime, precious metal extraction (SE, RoW): Anode slime treatment by pressure leaching and top blown rotary converter. Production of Silver by Möbius Electrolysis, Gold by Wohlwill electrolysis, Palladium to further processing

Natura 2000 und Management in Moorgebieten

Moorlebensräume und darauf spezialisierte Arten sind größtenteils stark gefährdet und unterliegen u. a. dem Schutz der FFH-Richtlinie. In den letzten Jahren spielt beim Moorschutz und der Wiedervernässung von Mooren neben dem Biodiversitätsschutz verstärkt auch der Aspekt des Klimaschutzes eine Rolle. Die Wiedervernässung und Revitalisierung von Mooren wirkt sich auch auf FFH-Lebensräume und -Arten sowie auf Arten der Vogelschutz-Richtlinie aus, deren Zustand sich dadurch verbessern oder verschlechtern kann. Letzteres kann zu Konflikten mit den Naturschutz-Richtlinien der EU führen. Im Rahmen des Workshops wurde ein Überblick darüber gewonnen, welche Zielkonflikte konkret zwischen EU-RL und Moorrevitalisierungsvorhaben auftreten, welche Erfahrungen bisher in diesem Zusammenhang mit der Handhabung der FFH-Verträglichkeitsprüfung vorliegen, welche Handlungsspielräume und welcher Handlungsbedarf aufgrund der Richtlinien bestehen (Erhaltungszustand, Verschlechterungsverbot, Entwicklungsziele). Der vorliegende Band gibt die Beiträge eines gleichnamigen Workshops an der BfN-Naturschutzakademie auf der Insel Vilm im November 2013 wieder. Die Beiträge stellen für die mit Moorrenaturierungsprojekten befassten Praktiker in Planungsbüros, Verbänden, Behörden und anderen Institutionen wertvolle Informationen dar, um ggf. auftretende Zielkonflikte schon zu Beginn der Planung einer Wiedervernässungsmaßnahme zu erkennen und frühzeitig geeignete Lösungen zu entwickeln.

Biodiversität der Flussauen Deutschlands

Die Publikation basiert auf der Zusammenstellung umfangreicher Daten, die im Rahmen verschiedener Publikationen und Gutachten zu o.g. Thema erhoben wurden. Bei aller Heterogenität zeigen die Ergebnisse deutlich, dass Flussauen nach wie vor Hotspots der Biodiversität sind - und dass Revitalisierungen der Auen sehr erfolgreich sein können. Obwohl Flussauen zu den artenreichsten Lebensräumen in Mitteleuropa gehören, besonders unter Belastungen und Veränderungen gelitten haben und vielfach renaturiert werden, fehlt bislang eine Zusammenfassung des Kenntnisstandes zu ihrer Biodiversität. O.g. Veröffentlichung soll diese Lücke füllen.

Ökologische und sozioökonomische Entwicklung einer Kulturlandschaft - 20 Jahre Monitoring in der Ise-Niederung

In der Ise-Niederung im Landkreis Gifhorn (Niedersachsen) wurde zwischen 1990 und 1995 ein umfassendes Erprobungs- und Entwicklungsvorhaben im Bereich Naturschutz und Landschaftspflege gefördert, das - mit Unterbrechungen - von 1989 bis 2007 durch ein interdisziplinär angelegtes Forschungsprogramm wissenschaftlich begleitet wurde. Ziel des Vorhabens war die Revitalisierung des Flüsschens Ise und seiner Aue unter den Hauptprämissen Förderung der Eigendynamik des Gewässers und Beibehaltung einer naturschutzorientierten Nutzung der Aue durch Land- und Forstwirtschaft. Damit sollten insbesondere die Lebensraumbedingungen für den ehemals heimischen Fischotter wieder hergestellt werden. Der vorliegende Band präsentiert die Auswertung und Dokumentation der langjährigen breit angelegten ökologischen wie auch sozioökonomischen Untersuchungsreihen. Damit liegen langjährige wissenschaftliche Daten zur Entwicklung einer "Normallandschaft" vor. Die Publikation richtet sich an Interessierte aus Wissenschaft und Praxis, die neugierig auf die Ergebnisse einer langjährig angelegten Untersuchung sind, die ökologische wie sozioökonomische Aspekte einbezieht, und diese für die eigene Arbeit sowie in einem weiteren Sinn für die Umsetzung der Nationalen Strategie zur biologischen Vielfalt nutzen wollen.

Ökonomische Bewertung naturverträglicher Hochwasservorsorge an der Elbe

Überschwemmungen wie die Elbeflut im August 2002 führen immer wieder die Notwendigkeit der Hochwasservorsorge vor Augen. Klimawandel und die Ausweitung der Siedlungs- und Verkehrsflächen verschärfen dabei das Risiko von Schäden auch durch kleinere und lokale Ereignisse. Die Bundesregierung fordert, zur Vorsorge gegen Hochwasserschäden auch naturverträgliche Maßnahmen durchzuführen wie Deichrückverlegungen, die Wiedergewinnung natürlicher Überschwemmungsflächen und eine Revitalisierung von Auen. Solche Maßnahmen schneiden jedoch bei traditionellen Kosten-Nutzen-Analysen, die nur die Hochwasser senkende Wirkung berücksichtigen, tendenziell schlecht ab - verglichen mit technischem Hochwasserschutz (Deichbau und -sanierung). Die vorliegende Studie erarbeitet eine Methodik, die zusätzlich die Wirkung der Auen auf die Lebensraum-, Schadstoffabbau- und Erholungsraumfunktion monetär erfasst. Mit dieser erweiterten Kosten-Nutzen-Analyse werden unterschiedliche Hochwasserschutzvarianten an der Elbe analysiert. Das Ergebnis: Naturverträgliche Hochwasserschutzmaßnahmen weisen aufgrund ihrer vielfältigen gesellschaftlichen Funktionen ein positives Kosten-Nutzen-Verhältnis auf. Eine Kombination aus technischen und naturverträglichen Maßnahmen an ausgewählten Stellen ist aus ökologischer und ökonomischer Sicht am sinnvollsten.

Anbindung des Schlauchgrabens an den Rhein

Das Projekt "Anbindung des Schlauchgrabens an den Rhein" wird vom Umweltbundesamt gefördert und von Stadt Mannheim, Fachbereich Grünflächen und Umwelt durchgeführt. Zielsetzung und Anlaß des Vorhabens: Der Schlauchgraben ist ein ehemaliger Seitenarm des Rheins, der durch langjährige Verlandungsprozesse vom Hauptstrom abgeschnitten wurde. Ziel ist es, die ökologischen Potentiale des Schlauchgrabens wieder nutzbar zu machen und ihn dadurch naturschutzfachlich aufzuwerten. Dies kann umgesetzt werden durch die Anbindung an den Rhein mittels eines offenen Grabens und durch die Vergrößerung der Abflussquerschnitte an den Wegkreuzungen. Nach Abschluss der Maßnahmen wird der Schlauchgraben bereits bei Mittelwasserverhältnissen durchströmt, was statistisch an 155 Tage/Jahr stattfindet. Dies verhindert ein frühzeitiges Trockenfallen des Schlauchgrabens und ermöglicht eine natürliche Auenentwicklung. Zusätzlich wird insbesondere das naturschutzfachliche Ziel, die Förderung der heimischen Amphibienfauna, dadurch erreicht. Für diese Gruppe wurde letztmalig 2012 durch einen stadtweite Kartierung im Ergebnis festgestellt, dass die Artenausstattung insgesamt sehr gut für das Stadtgebiet ist, aber es einen Mangel an geeigneten Laichgewässern gibt. Dies soll sich mit der Anbindung des Schlauchgrabens verbessern. Fazit: Das Projekt 'Anbindung des Schlauchgrabens an den Rhein' konnte durch die Fördermittel größtenteils fertiggestellt werden. Die lange Vorbereitungszeit hat dazu geführt, bereits im Vorfeld der Ausschreibung viele Fragestellungen geklärt und ggf. optimiert werden konnte. Allerdings waren die (finanziellen) Auswirkungen bei der Berücksichtigung der vorhandenen Gashochdruckleitung und der anderen in Franzosenweg liegenden Leitungen nicht in seiner tatsächlichen Dimension abschätzbar. Das Zusammenspiel zwischen dem Ingenieurbüro, der Baufirma und der weiteren Beteiligten, z.B. der Kampfmittelsondierungsfirma, liefen reibungslos. Die eingetretenen Verzögerungen sind schuldlos zustande gekommen. Sie basierten auf unvorhergesehene Ereignisse. Sie hatten keinen Einfluss auf die Kosten. Die andauernden niedrigen Pegelstände des Rheins lassen derzeit keine Aussage die tatsächlichen Erfolge zu in Bezug auf die Durchlässigkeit und auf die Nutzung durch Amphibien.

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