technologyComment of heavy mineral sand quarry operation (AU, RoW): There are two ways for mining zircon sand: dry & wet mining with the choice of mining depending on the structure of the geological deposit. During wet mining, floating dredges and a floating concentrator are utilized in an enclosed pond, where the concentrator moves behind the dredges. Wet mining is the preferred technique for large continuous deposits with amounts of clay. For all other types of HMS deposits (hard-ground deposits, discontinuous deposits and small tonnage high-grade deposits), dry mining is the most preferred mining process. Dry mining utilizes earth-moving machinery (loaders, excavators, scrapes) for the purposes of sand excavation and transportation to the concentrator. The mining unit plants used in dry mining are mobile in order to minimize the transport distance of the sand. After the transportation of the HMS to the respective concentrator, wet gravity separations techniques (spirals) are usually applied for the production of the heavy mineral concentrate (HMC), although some hard-rock sites use bulk froth flotation to extract the heavy minerals from the sand. The produced slurry from dry and wet mining is then fed to the concentrator, where the HMC (90-96% heavy minerals) is produced along with the tailings that are backfilled in the mined areas. The HMC is transported to a mineral separation plant (MSP), where the HMC is subjected to scrubbing, drying and is separated by magnetic, electrostatic and gravity separation, producing zircon sand, ilmenite and rutile, with the last two considered as byproducts. technologyComment of ilmenite - magnetite mine operation (GLO): No comment present
Das Projekt "Two stage gas generator for industrial wastes" wird vom Umweltbundesamt gefördert und von Eisenmann Maschinenbau KG durchgeführt. Objective: Thermic utilization of industrial residual system resp. production residues in a two stage incineration system under production conditions. The tests contain as well pre-trials for determination of the optimal system parameter as also permanent trial runs, for establishing of material and energy balances and for judgement of the operation reaction through a longer time period. By the work with this process the advantages shall be shown: - Profitability also with small residual material amount of 200-1000 kg/h - complete energetic utilization of the material - easy integrating in available heating systems, for example preswitching of an available boiler system - universal usability of energy - utilization of the product residues in the own factory for heating, process heat and evtl. electric current generation - reduction of the removal costs. General Information: The demonstration system, built in the smallest production scale, had been erected in the technical science department of the Company EISENMANN. The process principle is based on a mechanical pre-treatment, with which the material will be communited with a slitting rollers appliance and afterwards will be transported into a storage silo. From the silo the filling system continuously pushes in the waste material in the fluidized bed reactor, which has a quadratic free cross section of 500 x 500 mm and is provided with a 400 mm thick fireproof lining. A 1 m high piling up of quartz sand with a grain size of 0,4-1,6 mm serves as heat bearer medium. The piling up will be fluidized by the injection of hot flue gases. The advantages of a fluidized bed as pyrolytic stages are the following: - The fluidizing of the sand causes a uniform distribution of temperature - an intensive heat transition between sand and residual material is given - by the fluidizing a mechanical comminution of the material simultaneously takes place, with that the lump forming of the used material will be avoided - by a low oxygen, preheated fluidized gas a pyrolisation with under stoichiometric incineration takes place so, that a max. reaction temperature of approx. 600 degree of Celsius up to 700 degree of Celsius arises, with which still no slag forming appears. The following thermic processes proceed: The hot flue gases (approx. 650 degree of Celsius) contain 6-8 per cent oxygen. They hold the sand bed on approx. 550 degree of Celsius. The supplied residual material combustes in these conditions under stoichiometric. Through a short insulated connection line the pyrolitic gases reach in a vertical arranged combustion chamber. Here they will be burned with the help of a support burner by injection of fresh air with approx. 1100 degree of Celsius. Following the combustion chamber the flue gases will be diverted horizontally, before they give away again in a vertical heat exchanger their energy to a hot water circulation. After the heat exchanger the flue gases are still approx. 250 degree of Celsius...
Das Projekt "Europäische sand- und Kies Ressourcen: Übersicht und Auswirkungen von Entnahmen" wird vom Umweltbundesamt gefördert und von Christian-Albrechts-Universität zu Kiel, Sektion Geowissenschaften, Institut für Geowissenschaften durchgeführt. Quantifiction of marine aggregate usage and specific demands (incl. standardisation of methods of description of sand and gravel within Europe - Assessment of the methods used for the prospecting of marine aggregate resources - Near-field modelling of the physical an ecological impacts of offshore sand and gravel mining - Improvement in the understanding of bed regeneration processes - Far-filed modelling of the effects of dreding on adjacent coastlines. Prime Contractor: Fundacion AZTI, Oceanography and Marine Environment, Pasaia, Spain.
Das Projekt "Bau einer Kapillar-Sperre fuer das Oberflaechenabdichtungssystem einer Deponie" wird vom Umweltbundesamt gefördert und von Landkreis Leer, Abfallwirtschaftsbetrieb durchgeführt. As have been amply demonstrated by a number of scientific investigations, capillary barriers are an efficient type of sealing system that can be used as a final cover on landfills and remediation sites. This pilot project, covering two hectares of a sloping section of the landfill at Breinermoor in the German state of Lower Saxony, is set up to demonstrate that large-scale capillary barriers will be technologically feasible in a number of landfills in various locations. A capillary barrier consists of two sloping layers. Fine-grained sand is used in the capillary layer, which overlies a coarse-grained layer (the capillary block). The capillary barrier is an innovative sealing system which exploits the fact that a layer of fine sand has become highly saturated with water from above. Capillary forces counteract the power of gravity and prevent the water in the capillary layer from seeping down into the capillary block. Instead, the water is held just above the interface between the two layers and runs off laterally into a ditch containing a drain at the foot of the slope. In suitable applications, and given the correct choice of materials, a capillary block will provide an efficient surface seal.
Das Projekt "Entwicklung einer Asphaltmischanlage zur Beimengung der Reststoffe (Asche) aus Muellverbennungsanlagen in qualifizierte Bitumenprodukte; Anlage wird mit dehydriertem, verdichtetem Klaerschlamm aus Siedlungsabwasserklaerwerken betrieben" wird vom Umweltbundesamt gefördert und von HERRIED Straßenbau durchgeführt. The aim of the project is the development of an asphalt mixing plant to turn the residue (waste slags) produced by waste incinerators into qualified bituminous products. The process will be fuelled by dehydrated and densified sewage sludge from urban water purification processes. This demonstration project is applicable to any one of more than 9000 existing asphalt mixing plants in Europe. In particular, those fine fractions of wet ashes still being thrown away by the recycling market can be used to substitute natural sand in a process similar to the proven set-up with any conventional plant. The final product quality meets the current standard requirements. It also works with recycled asphalt. In the process described here, the sand ratio (d is 0-4 mm) in a specific asphalt formula is replaced by a certain slag material. This requires an additional feeder facilities for weighing or dosing and stocking. The slag enters the drying drum along with the mineral rigth from the start. Further processing of the material mixture is carried out in the same way as in any traditional asphalt mixing facility. However, the drum must have a different basic configuration to ensure the quality of the new product. This process sludge, delivered in the form of pellets, is used instead of gas or heating oil. In the rear wall of the drum, there is a solids blow burner for fuel. As dust has to be adjusted to the new drum conditions, the drum is thus constructed similar to a coal-dust burner.
Das Projekt "Thermische Behandlung von Staeuben und Sand in einer mittleren Stahl-/Edelstahlgiesserei unter besonderer Beruecksichtigung der Abgasreinigung" wird vom Umweltbundesamt gefördert und von Schmolz + Bickenbach durchgeführt.
Das Projekt "Umweltfreundliche mechanische Regenerierung von Giesserei-Mischaltsand" wird vom Umweltbundesamt gefördert und von Fischer Automobilguss durchgeführt. Die in einer Giesserei anfallenden Mischaltsande, die bisher deponiert wurden, werden getrennt nach Anfallstellen erfasst und die Sandqualitaeten physikalisch/chemisch bestimmt und klassiert. Je nach Qualitaet und Quantitaet werden verschiedene Vorstufen zur Aufbereitung vorgesehen. Anschliessend wird der Altsand in einer Trommel einer Schlag- und Scheuerbehandlung unterzogen. Dabei fallen 60 Prozent der eingesetzten Sandmenge als Regenerat an, das zur Herstellung von Coldbox-Kernen eingesetzt werden kann. Der anfallende Schwarzstoff (20 Prozent aktives Bentonit, 12 Prozent Kohlenstofftraeger) wird in den Formsandkreislauf zurueckgegeben. Der Reststoff soll nach Senkung des darin enthaltenen Kohlenstoffanteils auf unter 1 Prozent in Zementwerken eingesetzt werden.
Arbuscular mycorrhizal fungi (AMF) are mutualistic symbionts considered a key group in soil systems involved in the provision of several ecosystem services. Recently they have been listed by EFSA as organisms to be included in the test battery for the risk assessment of plant protection product (PPPs). This study aimed to contribute to improve the ISO Protocol (ISO 10832: 2009) by assessing the feasibility of using other AMF species under different test conditions. Overall, results showed that AMF species Gigaspora albida and Rhizophagus clarus (selected out of five AMF species) are suitable to be used in spore germination tests using the ISO protocol (14 days incubation with sand or artificial soil as substrate) to test PPPs. However, several modifications to the protocol were made in order to accommodate the use of the tested isolates, namely the incubation temperature (28†˚C instead of 24†˚C) and the change of reference substance (boric acid instead of cadmium nitrate). The need for these changes, plus the results obtained with the three fungicides tested (chlorothalonil, mancozeb and metalaxyl-M) and comparisons made with literature on the relevance of the origin of AMF isolates in dictating the adequate test conditions, emphasize the importance of adjusting test conditions (AMF species/isolates and test temperature) when assessing effects for prospective risk assessment targeting different climatic zones. So, further studies should be conducted with different AMF species and isolates from different climatic regions, in order to better define which species/isolate and test conditions should be used to assess effects of a particular PPP targeting a given climatic zone. © Springer Science+Business Media, LLC, part of Springer Nature 2018
Das Projekt "Entwicklung eines flexiblen und wirtschaftlichen Verfahrens zur thermisch-mechanischen Regenerierung von Giessereialtsanden" wird vom Umweltbundesamt gefördert und von Alb. Klein GmbH & Co. KG durchgeführt.
Das Projekt "Regenerierung von Kernformstoffen und Formstoffen" wird vom Umweltbundesamt gefördert und von Georg Fischer GmbH durchgeführt. Die Grossgussherstellung erfolgt kastengebunden auf einer automatischen Form- und Giessanlage. Beim Auspackprozess des Gusses aus der Form und nachgelagerten Prozessen bis zur Strahlerei wird eine weitgehende Trennung von Kern- und Formsand vorgenommen durch die Realisierung eines gestaffelten Kernsanderfassungssystems. Aus dem zu etwa 70 Prozent Kernsand bestehenden Mischsand werden durch eine spezielle Magnetseparierungsanlage weiterhin ausgesondert: bentonitgebundene Altsandreste, exotherme Speiserstoffe und Eisenstaeube. Als Ausgangsmaterial fuer die Regenerierung steht damit Kernaltsand zur Verfuegung, welcher mit reduziertem Energie- und Zeitaufwand mechanisch regeneriert wird. Gleichzeitig sinkt der Anteil nicht verwertbarer Reststoffe (Staub) aus der Regenerierungsstufe auf ca. 10 Prozent. Emissionen wie NOx, SO2 sowie gasfoermige organische Stoffe, die bei einer thermischen Regenerierung des Altsandes entstehen, entfallen gaenzlich. Die nicht mehr zu deponierende Altsandmenge betraegt 7.000 t/Jahr. Die Neusandeinsparung liegt in der gleichen Groessenordnung. Das gewonnene Regenerat wird ausschliesslich in der Cold-Box-Kernfertigung wieder eingesetzt.