technologyComment of cryolite production, from fluosilicic acid (GLO): The main production of cryolite involves hydrofluoric acid or fluosilicic acid. In both cases, the reactants can be combined with a variety of materials, such as Al2O3 · 3 H2O, Al2O3 · x NaOH, NaOH, NaCl, and Na2SO4. During the present reaction, fluosilicic acid is neutralised with sodium hydroxide. Then it reacts with Al2O3 to produce cryolite and silica. The reaction process is shown below: Al2O3 + 2H2SiF6 + 6 NaOH --> 2 Na3AlF6 + 2 SiO2 + 5 H2O It is difficult to predict how much of the cryolite is produced with the present reaction, since many production routes exist. The present inventory serves as an illustration of the cryolite production from fluosilicic acid. The alternative production route with HF is still considered to be the main production route (source: Ullmann encyclopedia, Cryolite, 2005). technologyComment of silica sand production (DE, RoW): Generally there are no differences in the quarrying process of silica sand compared to the “normal” sand process. An important difference is that silica sand is dried. It is assumed that the content of moisture before drying is about 5% and afterwards around 1%. Another difference is based on the high content of SiO2, which makes the raw material rarer. Losses in the conveyor belt transportation are taken into account.
Das Projekt "Carbon input and turnover in subsoil biopores" wird vom Umweltbundesamt gefördert und von Universität Göttingen, Büsgen-Institut, Abteilung Ökopedologie der gemäßigten Zonen durchgeführt. The carbon (C) input into the subsoil and especially the importance of biopores remains unclear. The aim of this project is to evaluate the contribution of biopores to the C transport and C turnover into the subsoil depending on crops with contrasting root systems. Biochemical properties of biopores of various origins (earthworm-derived, root-derived and mixed) will be studied in detail. C turnover in biopores of various origins will be studied by incubation and CO2 analysis. C input into the subsoil depending on the root system and on biopore density will be estimated by 13C labeling in the crop sequence experiment (CeFiT). The utilization of rhizodeposits by microbial groups in and out of biopores will be analyzed by 13C-PLFA. The distribution of enzyme activities around the biopores will be measured by recently developed soil zymography. The biopore formation by preceding crops and their use by main crops will be analyzed by 14C pulse labeling and imaging under controlled conditions. Mycorrhization of roots in and out of biopores will be analyzed in the CeFiT experiment and related to soil depths, depending on moisture and nutrient contents of the topsoil. Based on these studies, we will quantify the importance of biopores for C transport and C turnover and for microbial activity in the subsoil depending on preceding crops.
Das Projekt "Sub project: Marine Isotope Stage 11 in the eastern Mediterranean Sea: Nearest analog to the present day?" wird vom Umweltbundesamt gefördert und von Universität Bremen, Zentrum für marine Umweltwissenschaften durchgeführt. Marine isotopic Stage 11 (MIS11), some 400,000 years ago, provides the closest analog to the Holocene in terms of the configuration of the Earth s orbit around the Sun and the resulting strength and variability of solar insolation. Understanding the climate of MIS11 will thus aid in assessment of human impact on global climate and of the future of the present warm period. The Mediterranean acts as an amplifier of climate signals, responding to forcing from both the North, via the North Atlantic Oscillation and from the South, through shifts of the Intertropical Convergence Zone. This unique potential of the region to record different facets of MIS11 climate has never been explored. In this project, we will generate the first high-resolution multi-proxy records from eastern Mediterranean OOP cores, reconstructing the hydrography, climate and ecosystems of the region across the MIS11. We specifically aim to study the pattern of climate fluctuation during MIS11 as an analog of what might have been expected during the Holocene (MIS1) without human overprint. We will also determine when and how this Holocene-like interglacial ended and whether the plunge into a new ice age could have been predicted from precursor signals or events. Our results will help in evaluating scenarios of future climate change in this densely populated region, with obvious benefits to society in Mediterranean countries.
Das Projekt "Municipal wood energy center Rottweil" wird vom Umweltbundesamt gefördert und von Stadtwerke Rottweil durchgeführt. Objective: Electricity production by gasification of 6350 tonnes per year of fuel wood from forestry waste, communal wood waste and energy plantations in a three stage gas generator in the district of Rottweil. 100 ha of short rotation forestry (poplar and other species) will be planted in a first step. The power output amounts to 990 kWe and additional use of waste heat and gas for heating purpose is foreseen. The production amounts to 7,130,000 kWh. A particular attention will be given to the fuel wood logistics and notably to a 3 months capacity fuel wood storage. The payback time is estimated at 15 years. General Information: The 600 m3 silos, gasifier modules, cogeneration and control room are installed underground. This minimizes noise and also enables the trucks to drive over the silos for direct unloading. The woodchips are dried to approx. 25 per cent moisture content in a vertical rotating conical dryer by means of the available heat from the gas plant. The pre-dried woodchips enter the 3 stage EASIMOD 3500 kWh gasifier. The first stage is an underfeed co-current primary reactor producing primary gas with flying charcoal at about 650 deg. C. Gas is then reformed at approx. 900 deg. C in a separate Venturi burner with secondary air inlet and charcoal/activated carbon extraction. Tars and phenols are cracked. The third step is a separate glowing coke reactor which acts as a safety for tars and phenols cracking and as a gas heating value booster. Gas cleaning consists of dry dedusting in multicyclones, followed by a two-step scrubbing (impingement scrubber plus packed scrubber). The gas is cooled down to approx. 20 deg. C and the heat obtained is then used for predrying the fuel in the woodchips dryer. Ammonia washed out in the scrubbing water is stripped in a packed bed stripper. A waste water treatment plant is foreseen. The dryer, gasifier and gas scrubber are conceived as separate frame-mounted modules. The whole plant runs automatically. The electricity produced will be fed into the medium 20 KV voltage municipal grid. The heat recovered simultaneously will be used in a following step for the heating of a nearby village.
Das Projekt "Liegedauer von Holzschwellen in U-Bahn-Tunneln" wird vom Umweltbundesamt gefördert und von Universität Hannover, Institut für Verkehrswesen, Eisenbahnbau und -betrieb durchgeführt. Während die Liegedauer von Holzschwellen auf der feien Stecke durch Jahrzehnte lange Praxiserfahrung bekannt ist, bestehen hinsichtlich der Nutzungsdauer von Holzschwellen in U-Bahn-Tunneln nur unzureichende Erfahrungen. Um Erkenntnisse über das Langzeitverhalten von Tunnelschwellen zu erlangen, wurden bis zu 45 Jahre alte Kiefernschwellen aus dem Tunnelnetz der Hamburger Hochbahn AG untersucht. Anhand von Feuchtigkeitsmessungen, Bohrresistenzprüfungen, Herausziehversuchen an Schwellenschrauben und der Durchführung von Sägeschnitten konnte nachgewiesen werden, dass das Langzeitverhalten von Holzschwellen in U-Bahn-Tunneln dominierend durch die mechanische Beanspruchung bestimmt wird. Eine Begrenzung der technischen Nutzungsdauer infolge biologischer Beanspruchungen konnte aufgrund der dauerhaft trockenen Lagerung und der gedämpften Klimaschwankungen in den betrachteten U-Bahn-Tunneln ausgeschlossen werden. Im Ergebnis konnten an den untersuchten Schwellen unabhängig von ihrem Alter keine Schäden festgestellt werden, die die technische Nutzungsdauer begrenzen. Mit Ausnahme besonderer Beanspruchungen, wie sie z.B. in engen Bögen auftreten, ist ein bevorstehendes Ende der Nutzungsdauer auf absehbare Zeit nicht zu erwarten. Für die 45 Jahre alten Tunnelschwellen wurde eine weitere Liegedauer von wenigstens 20 Jahren prognostiziert.
Das Projekt "Teilprojekt 1" wird vom Umweltbundesamt gefördert und von Technische Universität Berlin, Institut für Ökologie, Fachgebiet Standortkunde und Bodenschutz durchgeführt. Die PROFIL TDT Sonde ist ein Messsystem, das zur kontinuierlichen Messung des Wasser-, Salz- und Temperaturhaushalts von Böden unter Freilandbedingungen eingesetzt werden soll. Die Sonde misst mittels des Time Domain Transmission Verfahrens in verschiedenen Tiefenbereichen des Bodens. Ein klassischer Anwendungsbereich für solche Sonden sind landwirtschaftliche Bewässerungssysteme. Hier kann durch das Monitoring der Bodenfeuchte und der Salzdynamik im Bodenprofil der Verbrauch von Bewässerungswasser optimal gesteuert werden. Gleichzeitig kann frühzeitig die Anreicherung von Salzen im Boden erkannt werden und einem Verlust der Bodenfruchtbarkeit entgegen gewirkt werden. Dies spielt besonders in Regionen mit Wasserknappheit (hauptsächlich aride Klimagebiete) und im Zuge des Klimawandels eine wichtige Rolle. Auf diese Weise kann ein wertvoller Beitrag zur nachhaltigen landwirtschaftlichen Produktion geleistet werden. Weiter Anwendungsgebiete der PROFILE TDT Sonde sind die Überwachung von Altlasten, der Grundwasserschutz oder die Überwachung von Erdbauwerken (z.B. Deiche und Deponien). Das Messsystem soll deutlich preisgünstiger als bestehende Messgeräte angeboten werden. Mit Hilfe kabelloser Kommunikationstechnologien und durch Batteriebetrieb können die Messungen online vorgenommen werden. Das Entwicklungsprojekt ist eine deutsch-polnische Kooperation zwischen der Technischen Universität Berlin, der UP GmbH Cottbus, dem Bohdan Dobrzanski Institut für Agrophysik (IPAN) in Lublin und der E-Test Ltd. Aus Lublin.
Das Projekt "Smart monitoring of historic structures (SMOOHS)" wird vom Umweltbundesamt gefördert und von Universität Stuttgart, Otto-Graf-Institut, Materialprüfungsanstalt durchgeführt. Objective: Historic structures are often of extraordinary architecture, design or material. The conservation of such structures for next European generations is one of the main future tasks. To conserve historic structures it is more and more required to understand the deterioration processes mainly caused by the environment. In certain cases continuous monitoring systems have been installed to obtain information about the deterioration processes. However, most of these monitoring systems were just weather or air pollution data acquisition systems and use only basic models for data analysis. The real influence of the environment to the structure or the structural material is often unaccounted for. That means that the structural resistance is just calculated from the measurements and not determined by sufficient sensors. Another aspect is the fact that most monitoring systems require cabling, which is neither aesthetically appealing nor in some cases applicable due to the needed fastening techniques. The proposed project aims at the development of competitive tools for practitioners which goes beyond the mere accumulation of data. Smart monitoring systems using wireless sensor networks, new miniature sensor technologies (e.g. MEMS) for minimally invasive installation as well as smart data processing will be developed. It will provide help in the sense of warnings (e.g. increase of damaging factors) and recommendations for action (e.g. ventilation or heating on/off, etc.) using data fusion and interpretation that is implemented within the monitoring system. The development will consist of small smart wireless and robust sensors and networks, with sensors for monitoring of e.g. temperature, humidity, air velocity, strain and crack opening, acoustic emissions, vibration, inclination, chemical attack, ambient and UV light, with built-in deterioration and material models, data pre-processing, and alarm functions to inform responsible persons about changes of the object status.
Das Projekt "Zuschlaege auf Messwerte fuer Mauerwerk" wird vom Umweltbundesamt gefördert und von Forschungsinstitut für Wärmeschutz e.V. München durchgeführt. Messung des Feuchteeinflusses auf die Waermeleitfaehigkeit von Mauerwerksprobekoerpern.
Das Projekt "Erzeugung von Energie aus Biomasse und organischen Abfaellen durch schnelle Pyrolyse" wird vom Umweltbundesamt gefördert und von Bio-Energy GmbH durchgeführt. Objective: The conversion of biomass and organic waste into high value energy products. Expected energy production is 1 220 TOE/y. General Information: Biomass and organic waste (waste wood, sawdust, bark, straw etc.) is crushed into scraps of 2-3 cm length and 1 cm width, and dried to +/- 15 per cent moisture content by the process gas. The dried crushed waste is then pyrolysed at 500-600 C in a vertical reactor: charcoal is continuously extracted from the bottom of the reactor then cooled, crushed and pressed into briquets. Gases escape from the upper part of the reactor, undergo dust extraction in a cyclone and are then cooled to 80 C in a spray tower by adding water. This temperature lies above the dew point; therefore, no condensate is produced. After leaving the spray tower the oil, in the form of an aerosol, is enlarged in a radial fan. The oil droplets are then removed in a separator. Non-condensable gases are burned and the flue gases are used mainly for drying of charcoal briquets and waste raw materials. Achievements: Several modifications were carried out on the plant in 1986. A pneumatic knocker was installed to avoid bridge building of material in the converter, the converter air inlet pipes were modified, the briquet elevator was replaced by an inclined belt conveyor, and the char outlet flap was improved to avoid clogging and to ensure the converter was air tight. During initial trials the outlet flap was not air tight and uncontrolled combustion was taking place in the converter. Following the above modifications charcoal output of about 25 per cent was achieved. Pyrolytic oil recovery ranged from 4. 6-7. 1 per cent, of biomass dry matter, lower that the 10 per cent forecast. Recent tests have shown that the pyrolytic oil can be contaminated with solid particles and fuel filtration is therefore needed. Use of the oil as a commercial engine fuel has yet to be demonstrated, though some success has been achieved with newly designed engines. The plant is not currently operational as some further modifications are required on the converter and funds to carry out this work are not available.
Das Projekt "Trocknungs- und Kuehlmaschine fuer Granulit und andere Granulate" wird vom Umweltbundesamt gefördert und von Schlingmeier Quarzsand durchgeführt. Objective: The purpose of this project is to test a new type of drying drum for granulite and other granular materials, which, in conjunction with heat recovery methods and the utilization of waste heat, should achieve an energy saving of about 34 per cent compared with conventional methods. This corresponds to an annual oil saving of about 470 toe. General Information: A patent application has been made for a new type of drying drum for the drying of granulite. Its operational efficiency is to be demonstrated in this demonstration project. The drum consists of an intensive drying zone and a re-evaporation zone. The combustion gases from an oil burner heat the granulite to more than 100 deg. C in the intensive drying zone, whereby approximately 75 per cent of the moisture in the sand evaporates. The sand enters the re-evaporation zone, which is operated at a slight vacuum. This process causes re-evaporation to the necessary residual moisture content, and is supported by hot, dry air from the downstream sand cooling (heat recovery). The combustion gases from the intensive drying zone and the dry air from the re-evaporation zone, including the water vapour fractions, are extracted in the central section of the drum. The purification of these exhaust gases is carried out in the dust separator. The compressed air needed in the combustion and transportation processes (6-8 bar) is produced by compressors. Naturally, dry air is produced as cooling air. This is used as combustion air for the oil burner (heat recovery). In comparison with conventional method, the specific energy demand for granulite drying is planned to be reduced by about one-third by the combination of a drying process with re-evaporation and heat recovery. The necessary new components are integrated into operational plant already in existence in Königslutter. Achievements: Alterations, subsequent work: After trial runs, several elements had to be replaced, altered or re-ordered. The Krupp burner was re-ordered. To start with, we had problems with the burner from the firm of Kleinewefers. After controls, subsequent work and improvements, this burner is now working perfectly. The drive was altered. The gear drive was replaced by a chain drive. The electrical controls were altered. regulation apparatus, automatic parts were altered, improvement, worked on etc. Planned alterations for new plant: a) Mechanical twist filters are no longer permitted as filters; in future, special cloth filters must be fitted. b) The angle of the drying drum must be some degrees higher, making installations easier and the performance higher. c) A sand sluice must be installed at the suction part for the exhaust gases, causing less sand in the exhaust gases. d) The burner should be constructed with a smaller volume and greater performance, producing a smaller surface to the outside and better cooling by the compression air on the outer casing. e) Large-scale planning, new planning, thus less conveying ...