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Markt für Salzsäure, ohne Wasser, in 30%igem Lösungszustand

technologyComment of Mannheim process (RER): Production of sodium sulfate and HCl by the Mannheim process. This process can be summarized with the following overall stoechiometric reaction: 2 NaCl + H2SO4 → Na2SO4 + 2 HCl technologyComment of allyl chloride production, reaction of propylene and chlorine (RER): based on industry data in the US and Europe technologyComment of benzene chlorination (RER): Clorobenzenes are prepared by reaction of liquid benzene with gaseous chlorine in the presence of a catalyst at moderate temperature and atmospheric pressure. Hydrogen chloride is formed as a by-product. Generally, mixtures of isomers and compounds with varying degrees of chlorination are obtained, because any given chlorobenzene can be further chlorinated up to the stage of hexa-chlorobenzene. Because of the directing influence exerted by chlorine, the unfavoured products 1,3-dichlorobenzene, 1,3,5-trichlorobenzene and 1,2,3,5-tetrachlorobenzene are formed to only a small extent if at all. The velocity of chlorination for an individual chlorine compound depends on the compound's structure and, because of this, both the degree of chlorination and also the isomer ratio change continuously during the course of reaction. Sets of data on the composition of products from different reactions are only comparable if they refer to identical reaction conditions and materials having the same degree of chlorination. By altering the reaction conditions and changing the catalyst, one can vary the ratios of different chlorinated products within certain limits. Lewis acids (FeCl3, AlCl3, SbCl3, MnCl2, MoCl2, SnCl4, TiCl4) are used as principal catalysts. The usual catalyst employed in large scale production is ferric chloride, with or without the addition of sulfur compounds. The ratio of resulting chlorobenzenes to one another is also influenced by the benzene:chlorine ratio. For this reason, the highest selectivity is achieved in batch processes. If the same monochlorobenzene:dichlorobenzene ratio expected from a batch reactor is to result from continuous operation in a single-stage reactor, then a far lower degree of benzene conversion must be accepted as a consequence of the low benzene:chlorine ratio). The reaction is highly exothermic: C6H6 + Cl2 --> C6H5Cl + HCl ; delta H = -131.5 kJ/mol Unwanted heat of reaction can be dissipated either by circulating some of the reactor fluid through an external heat exchanger or by permitting evaporative cooling to occur at the boiling temperature. Circulation cooling has the advantage of enabling the reaction temperature to be varied in accordance with the requirements of a given situation. Evaporative cooling is more economical, however. Fractional distillation separates the products. Iron catalyst is removed with the distillation residue.Unreacted benzene is recycled to the reactor. technologyComment of hydrochloric acid production, from the reaction of hydrogen with chlorine (RER): HCl can be either directly prepared or generated as a by-product from a number of reactions. This dataset represents the production of HCl via the combustion of chlorine with hydrogen gas. The process involves burning hydrogen gas and chlorine in a gas combustion chamber, producing hydrogen chloride gas. The hydrogen chloride gas then passes through a cooler to an absorber where process water is introduced, producing aqueous hydrochloric acid. H2 + Cl2 -> 2 HCl (exothermic reaction) References: Althaus H.-J., Chudacoff M., Hischier R., Jungbluth N., Osses M. and Primas A. (2007) Life Cycle Inventories of Chemicals. ecoinvent report No. 8, v2.0. EMPA Dübendorf, Swiss Centre for Life Cycle Inventories, Dübendorf, CH. technologyComment of tetrafluoroethylene production (RER): The production of fluorochemicals and PTFE monomers can be summarized with the following chemical reactions (Cedergren et al. 2001): CaF2 + H2SO4 -> CaSO4 + 2HF (1) CH4 + 3Cl2 -> CHCl3 + 3HCl (2) CHCl3 + 2HF -> CHClF2 + 2HCl (3) 2 CHClF2 + heat -> CF2=CF2 + 2 HCl (4) This dataset represents the last reaction step (4). Parts of the production are carried out at high pressure and high temperature, 590 ºC – 900 ºC. The first reaction (1) takes place in the presence of heat and HSO3 - and steam. The inventory for the production of hydrogen fluoride can be found in the report (Jungbluth 2003a). Reaction (2) is used to produce trichloromethane. Reaction 3 for the production of chlorodifluoromethane takes place in the presence of a catalyst. The production of PTFE (4) takes place under high temperature pyrolysis conditions. Large amounts of hydrochloric acid (HCl) are generated as a couple product during the process and are sold as a 30% aqueous solution. A large number of other by-products and emissions is formed in the processes (benzene, dichloromethane, ethylene oxide, formaldehyde, R134a, and vinyl chloride) and small amounts of the highly toxic perfluoroisobutylene CF2=C(CF3)2. The by-products in the production of monomers can harm the processes of polymerisation. Because of this, the refinement of the production of monomers has to be very narrow. This makes the process complex and it contributes to a high cost for the PTFE-laminates. (Cedergren et al. 2001). References: Althaus H.-J., Chudacoff M., Hischier R., Jungbluth N., Osses M. and Primas A. (2007) Life Cycle Inventories of Chemicals. Final report ecoinvent data v2.0 No. 8. Swiss Centre for Life Cycle Inventories, Dübendorf, CH.

Heat recovery in the production of phosphoric acid

Das Projekt "Heat recovery in the production of phosphoric acid" wird vom Umweltbundesamt gefördert und von BK Ladenburg GmbH durchgeführt. Objective: The combustion of yellow phosphorus generates 24,350 kJ of heat per kg of the substance. The large-scale production of phosphoric acid involves the combustion of yellow phosphorus. The considerable amounts of heat generated in this process have been evacuated by means of cooling water. The project suggests to utilize this heat, in the future, for the generation of steam and to have it converted into electric power. This process-heat recovery enables considerable savings of primary energy (coal, oil, gas). General Information: The heat generated by the large-scale combustion of phosphorus is absorbed, in an acid tower, by recirculating acid. The recirculating acid then releases the heat previously absorbed into a heat exchanger (cooling water). The amounts of heat thus transferred are subsequently released, mainly in the form of steam, from the cooling tower into the atmosphere. Now, the new method suggests an upstream combustion chamber before the acid tower, thus utilizing a major part of the heat generated in the combustion of yellow phosphorus for the production of energy. The new method represents an energy-recovery process on a very high temperature level, with the possibility to produce high-pressure to medium-pressure steam with subsequent power/heat coupling. The estimated energy generation, at 8000 hours, would be as follows: Steam 15 t/h = 120,000 t/a with steam-pressure reduction from 80 bars/550 degree of Celsius to 40 bars/450 degree of Celsius. Electric power: 550 kWh = 4,400 mWh/a. Achievements: The project cannot be carried on, for the following reasons: - The capital expense (investment), in view of the actual cost level, will be approx. 30-40 per cent higher than estimated at the time of submission. - The capital payback period, due to the price decline for primary energy, will be excessively long (7 years); longer than there is an assured supply of phosphorus. - Since 1985, in view of a modified strategy, our company has increased its efforts to manufacture speciality products rather than to produce mass phosphates (commodities); this will lead to a reduced demand of phosphorus in the future. - A drastic collapse, since early 1986, in the sale of phosphate salts used in washing powers, detergents, and cleaning agents, will further reduce the amounts of phosphorus needed in the manufacture of our product line. - A major aspect of the project was the purchase of energy by Joh. A. Benckiser, with whom we have a joint network. Joh. A. Benckiser are no longer prepared to purchase any such energy.

Oxycoal AC - Phase 2b

Das Projekt "Oxycoal AC - Phase 2b" wird vom Umweltbundesamt gefördert und von RWTH Aachen University, Lehrstuhl für Wärme- und Stoffübertragung durchgeführt.

Vorhaben 2.3.4.A

Das Projekt "Vorhaben 2.3.4.A" wird vom Umweltbundesamt gefördert und von Technische Universität Darmstadt, Fachgebiet Reaktive Strömungen und Messtechnik durchgeführt. Die TU Darmstadt entwickelt ein Laser-Hygrometer auf Basis der Tunable Diode Laser Absorption Spectroscopy (direkt-TDLAS) zur Zwei-Linien-Thermometrie an Hochdruck-Brennkammern. In einem zweiten Schritt wird planare laserinduzierte Fluoreszenz am OH-Radikal zur zeitlich hochaufgelösten Diagnostik in der Hauptreaktionszone einer Gasturbinenbrennkammer angewendet. Zunächst wird eine Selektion geeigneter Absorptionslinien und die Neubestimmung deren spektroskopischer Liniendaten durchgeführt. An die Charakterisierung der Laser schließt sich die Konzeption des Spektrometers und die Erprobung an einem Modellbrenner der RSM-Hochdruckkammer an. Schließlich wird das Spektrometer zur Gastemperaturmessung an der Versuchsbrennkammer HBK2(DLR Köln) eingesetzt. Des Weiteren wird die Eignung der Nutzung des an den Brennkammerwänden entstehenden Streulichts untersucht. Im Bereich der Highspeed - OH- PLIF wird die Einkopplung der UV-Laserstrahlung in die Brennkammer realisiert. Darauffolgend erfolgt die PLIF Messung am SCARLET Rig (HBK3) an der DLR Köln.

Nutzung von Abwaerme fuer die Beheizung von Gewaechshaeusern

Das Projekt "Nutzung von Abwaerme fuer die Beheizung von Gewaechshaeusern" wird vom Umweltbundesamt gefördert und von Marion Gartenbau Handelsgesellschaft durchgeführt. Objective: To recover the waste heat available from a coal power plant to warm a greenhouse by treating it in such a way that it becomes possible to collect the thermal energy contained in the hot ashes gathered in the boiler combustion chambers. Forecasted annual energy saving is +- 1500 TOE. General Information: Waste water of the two electric generating sets of 120 and 300 MW in the Ensdorf coal power plant is to be used for the project. Low temperature waste water flow rate is 460 m3/h and the greenhouse, warmed by recovered heat, is located 3 Km from the plant. This is comprised of three systems, for, as follows: - energy recovery - delivery to and from the greenhouse - thermal devices for heating and temperature control. The energy recovery system involves the mixing of water and ash into 4 mm dia. granules; a basin to catch discharged water; a circulating pump to forward water to a heat exchanger, and a flow rate and temperature control system. Water is conveyed to and from the greenhouse via a 300 mm dia. pipe. The 25000 m2 greenhouse surface area is served by a pipe system and by a heat integrating system formed by an independent closed circuit. This is fed by an additional boiler, circulation pump and circuit. Service water is fed at 60 degree. C and the temperature difference between greenhouse and exterior is fixed at 30 degree. C for design purposes.

Phase III

Das Projekt "Phase III" wird vom Umweltbundesamt gefördert und von Babcock Kraftwerkstechnik durchgeführt. In der Gasreinigungsstufe eines Kombikraftwerkes auf Basis Druckfeuerung soll das aus der Brennkammer kommende Heissgas soweit gereinigt werden, dass es zum Antrieb einer Gasturbine eingesetzt werden kann. Fuer die Schlackenabscheidung wurde der Schuettschichtabscheider als optimale Loesung gefunden. Fuer die Alkaliabscheidung wird u.a. mit speziellen Gettermaterialien als Absorben gearbeitet. Bei der weiteren theoretischen und experimentellen Entwicklungsarbeit an dem Schuettschichtabscheider soll neben der Optimierung der Abscheidewirkung eine Scale-up Methode ausgearbeitet werden. Bei der Alkaliabscheidung wird zum einen der Mechanismus der primaeren Abscheidung an der Fluessigasche im FA-Abscheider untersucht, desweiteren soll ein Gettermaterial mit optimalen Eigenschaften identifiziert werden. Um die Gesamtabscheidung von Schlacke und Alkalien zu optimieren, sollen auch Methoden zur Minimierung des Schlacke- und Alkaliaustrages aus der Brennkammer untersucht werden.

Reducing CO and Nox emissions from coking ovens by means of a novel, composite heating system

Das Projekt "Reducing CO and Nox emissions from coking ovens by means of a novel, composite heating system" wird vom Umweltbundesamt gefördert und von Ruhrkohle AG durchgeführt. Objective: The objective of the study is to obtain mathematical tools which will not only permit innovative new designs for flues (and so increase the safety margin at the planning state), but will also make it possible to improve heating conditions in existing systems by making fuller use of the scope for adjustments. General Information: Discussion of the greenhouse effect and more extensive knowledge of the effects of pollutants on man and nature have increased awareness with regard to the environment. An obvious consequence of this has been the introduction of more stringent requirements concerning the limitation of pollutant emissions which have subsequently shown up the shortcomings of the heating systems used for the various types of coking oven. The production targets which operators have to aim at for economic reasons mean that conventional heating systems increasingly cannot fully comply with requirements in respect of environmental and labour protection. The primary cause of this situation is the extreme complexity of coking oven heating systems. The main problem with coking ovens is that the lack of individual flow control for the large number of ceramic-lined combustion chambers prevents controlled regulation of effluent flows. The project will concentrate on the following points: A) Assessment, status of knowledge, planning: Planning of a modular model system based on a systematic analysis and evaluation of experience, findings and operational data as well as of information on possible measures to reduce CO and NOx emissions from coking oven heating flues, e.g. - stage combustion, staged air supply - internal flue gas recirculation, circular current - external flue gas recirculation. B) Model studies: 1. Construction of a modular model system for experimental flow and mixing studies. 2. Flow studies on models or part-models to establish optimum speed and mixing conditions in the coking oven heating flue. 3. Numerical simulation exercises covering flow, mixing and combustion processes in the model system. C) Operational tests: 1. Measurement of temperatures and concentrations in the heating flue, particularly CO release and NOx formation. 2. Application of the model results in the practical design of the new type of heating flue. 3. Control measurements under operational conditions to quantify the combustion process in the new flue.

Use of a new type of anthracite curner and boiler in a power station

Das Projekt "Use of a new type of anthracite curner and boiler in a power station" wird vom Umweltbundesamt gefördert und von Sophia-Jacoba GmbH, Steinkohlenbergwerk durchgeführt. Objective: To demonstrate the use of an innovative, low pollutant burner of low volability anthracite, in a power station, in combination with a boiler system linked to a coal mine, thus solving the problems of mineral oil substitutes, use of low volability coal, SO2 separation, nitrogen removal, adjustability and economy. General Information: The burner design, divided into pre-burner and main burner, means that the ignition and burning of the coal dust can be maintained without brick-lined burner walls and heated combustion air. Due to the type of air passage and course of combustion, the combusted ash is drawn off dry; the boiler can be dimensioned without the need to take waste gas loading into account. The direction of the air and combustion allows 'the cold' combustion with low NOx concentrations. By the addition of lime dust, waste gases are desulphurised in the burner. After grinding to dust, fine coal is passed from storage silos to 7 burners then passed for pre-burning where it is ignited using propane gas; this is gradually decreased (after warming the pre -burner) as the coal dust passes in. This, then, continues to burn by recirculation of hot exhaust gases and continuous glowing coal-dust residue at the end of the pre -burner/start of the main burner. Air supply is via nozzles at the end of the burner which allows combustion control, termination and separation of air particles for easy disposal. To reduce SO2, lime dust is added in the main burner. Waste gas is filtered prior to emission to the atmosphere. The advantage of low-volability coals are: - easier storage (fewer volatile components); - easier transport by road, without need for special measures; - no danger from explosion since anthracite dust is not self -igniting, and there is no risk to groundwater. It is comparable to gas or oil-fired systems from the viewpoint of handling, storage and burning. Achievements: The burners were able to ignite and burn low volatile coal in the combustion chambers of this unit, however, an operation of the boiler was not possible. Reasons were the temperature level, flow behaviour, heat expansion and instabilities of the feed water flow. Thus the project failed. The calculation of expected and actual simple payback was originally based on a comparison with oil burning installations. Based on today's oil price a re-evaluation does not turn out favourable for coal. Furthermore, a realistic comparison cannot be conducted due to the defective boiler.

Verbrennung von Kohle fuer das Brennen von Ziegelsteinen

Das Projekt "Verbrennung von Kohle fuer das Brennen von Ziegelsteinen" wird vom Umweltbundesamt gefördert und von Gebrüder Löhlein Ziegelwerke durchgeführt. Objective: To convert a brick kiln fired with heavy oil to coal firing and to examine the effects of the burning of coal on the specific heat consumption, the quality of the product and the occurring ashes. On the basis of preliminary examinations on other kilns, an energy saving of more than 55 per cent is anticipated compared with oil-firing. General Information: The brick tunnel kiln to be converted to coal firing is to be equipped with an intermittent coal firing facility and tested. For this purpose, the necessary coal preparation facilities (feed bunker, transport systems, hammer mill, daily bunker and coal stokers at the blowing in points) and the special burner systems are to be developed and adapted to suit the specified tunnel kiln. The overall system will then be tested and, if necessary, modified depending on the product quality. Finally, the operating efficiency of the coal firing facility is to be tested during a longer demonstration operation period. The concept for the coal firing facility was based on the use and testing or different types of coal with various grain sizes to be able to optimize the requirements on coal quality and grain size both for separation and charging. The driest possible fine coal with a grain size of 0 - 6 mm is necessary for the blowing device. The erected preparation facilities comprise a feed bunker, from which the rough coal is conveyed to the hammer mill via a dispatch belt. After being ground to the necessary grain size, the fine coal is transported by pipe chain conveyers to the dosing appliances on the tunnel kiln in the form of coal stockers. They intermittently charge a coal-air mixture into the combustion planes of the kiln through lateral slits via so-called guide tubes. The ends of the tubes, which are fitted with baffle plates, protrude into the combustion channel. They are incandescent (hot bulb ignition) and cause the ignition of the mixture. Charging is effected in a 30-second rhythm alternating with every fourth row of the burner tubes. In the cases of intermittent charging, the coal-air mixture is pressed against the baffle plate with a high pressure and passes into the furnace area via the lateral slits in the incandescent tubes. Combustion is almost explosive. The intermittent control of the air feed is effected by a central closed-loop control facility via solenoid valves. Achievements: In a 26 week operation period, a mean fuel consumption of 1500 kJ/kg of fired bricks including drying was achieved. This corresponds to an energy saving of about 42 per cent when compared to operation with heavy heating oil. Although the target was not achieved, a considerable saving quota was realized. In the meantime, the facility has been demonstrated to several hundred interested parties from the brick industry and has therefore made an important contribution to the necessary spread of the experience and information gained in the course of this project.

2.2.3b FLOX Öl

Das Projekt "2.2.3b FLOX Öl" wird vom Umweltbundesamt gefördert und von Deutsches Zentrum für Luft- und Raumfahrt, Institut für Verbrennungstechnik durchgeführt. Dieses Vorhaben ist Teil des Verbundprojekts COOREFLEX-turbo (Turbomaschinen - Schlüsseltechnologien für flexible Kraftwerke und eine erfolgreiche Energiewende). Im Mittelpunkt des Projekts steht die Integration einer Flüssigbrennstoffstufe in das verbesserte, brennstoffflexible FLOX® Verbrennungssystem. DLR VT wird mit Siemens zusammenarbeiten und das Verbrennungssystem im Labormaßstab charakterisieren. Die Brennstoffdüsen sollen die Zweibrennstofffähigkeit eines FLOX® basierten Brenners für Öl/Wasseremulsion ermöglichen und für Brennkammersysteme maximaler Effizienz einsetzbar sein. Auch mit dem Backup-Brennstoffinjektor sollen niedrige Schadstoffemissionen erzielt werden. Durch die damit erzielte Maximierung der Versorgungssicherheit der Gasturbinen der nächsten Generation wird ein weiteres, essentielles Kriterium durch diese neuartige Technologie erfüllt. Zur Analyse unterschiedlicher Varianten der Flüssigbrennstoffeindüsung sollen Hochdruckexperimente durchgeführt werden Das Vorhaben stellt sich drei konkrete Arbeitsziele: Ein neuer Versuchsträgers im Labormaßstab für generische 1-Düsenanordnungen für den Hochdruckprüfstand HBK-S des DLR Instituts VT wird an die Flüssiginjektortechnologie angepasst (er steht aus einem anderen Vorhaben zur Verfügung). Mit seiner Hilfe werden die neuen Eindüsungskonzepte in den Tests untersucht und charakterisiert. Durch die Anwendung von laserdiagnostischen Messmethoden werden umfangreiche und detaillierte Validierungsdatensätze gewonnen.

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