Query: spenninger, claus

title: Buchner, Friedrich Karl Christian Ludwig (sometimes Louis) (1824 99)

title: Laura Meneghello, Jacob Moleschott: A Transnational Biography: Science, Politics, and Popularization in Nineteenth Century Europe, Bielefeld: transcript 2017. 488 S. EUR 49,99. ISBN 978 3 8376 3970 4.

title: Ein "gedankenloser Kreislauf" Form und Materie in der Physiologie um 1850

title: Thermal damage of sulfur processed chamber under Claus operating reaction conditions A case study
abstract: The sulfur from acid gas and sour gas is recovered to produce useful sulfur products. The claus reaction is industrially important process to recover sulfur from corrosive acid and sour gases. To achieve claus reaction, high temperature reactor is utilized under controlled conditions. The Claus combustion reaction heater made of 94% alumina refractory bricks were damaged under ideal equilibrium operating conditions. The first principle mathematical model was developed to measure the temperature profiles at hot face bricks and its interfaces to predict outer steel surface temperature. The maximum outer steel wall surface temperature was measured as 548.6 degC using thermograph experiments and compared against the predicted temperature. Large variations in temperature differences have confirmed that the refractory wall was damaged due to abnormal reactions. This thermal damage is discussed and presented with various evidences from visual inspection. The hot face wall bricks, matrix blocks and orifice throat were damaged and presented by macroscopic visual inspection. However, hardness of the steel shell is within specified limit. Therefore, the refractory repair inside the reactor and thermal insulation of external shell has been proposed to prevent steel shell from creep, graphitization, and high temperature oxidization and corrosion damages.

title: Modeling and multi optimization of thermal section of Claus process based on kinetic model
abstract: The Claus process consists of two basic stages: thermal and catalytic sections. In this study, modeling by a kinetic model and multi objective optimization of the thermal section of Claus process were described. The industrial data of the South Pars Refinery in Asaluyeh, Iran was used to validate this model. In order to investigate the influences of the inlet flow rates of fuel and air, inlet stream temperature, furnace pressure and waste heat boiler (WHB) outlet temperature on the sulfur recovery efficiency, the steam production and the H2S/SO2 ratio, a sensitivity analysis was done by simulator software. Three objects of the sulfur recovery efficiency, the steam production and the H2S/SO2 ratio were optimized by using the software and a multi optimization approach based on the response surface methodology. The results showed that the decrease of the sulfur recovery efficiency from 0.6129 to 0.6099 leads to the addition of 8.54 Kg mole/h to the medium pressure steam production capacity and more closeness of the H2S/SO2 ratio to number 2 for better performance of the catalytic section. However, the 66% improvement in the H2S/SO2 ratio leads to increase the conversion of H2S in the catalytic section, compensating the decrease of the sulfur recovery efficiency in the thermal section. Moreover, the total fuel consumption was reduced about 0.6843 kg mol/h.

title: Roles of hydrogen sulfide concentration and fuel gas injection on aromatics emission from Claus furnace
abstract: Acid gas (H 2 S and CO 2 recovered from sour feedstocks is treated in Sulfur recovery units (SRU) to obtain sulfur. The frequent changes in acid gas composition often result in lean acid gas, containing higher volume of CO 2 than H 2 S. Lean acid gas causes flame instability that result in inefficient destruction of feed impurities in Claus furnace. To mitigate this problem, fuel gas (with >90% CH 4 is co fired with acid gas to increase furnace temperature and prevent flame extinction. The addition of fuel gas in Claus furnace may aggravate the production of polycyclic aromatics hydrocarbons (that cause frequent catalyst deactivation) and CS 2 and COS (that reduce sulfur yield) Clearly, the amount of fuel gas injected into Claus furnace needs to be optimized. The previous optimization studies have given less importance to the roles of H 2 S concentrations in acid gas and the injected fuel gas on the production of aromatics and organosulfur species. This paper explores the fate of undesired aromatics, COS and CS 2 in the Claus furnace over a wide range of H 2 S concentrations in acid gas using a detailed reaction mechanism. Experimental data on species concentration from a SRU is presented, and is used for mechanism validation. The effect of fuel gas co firing with typical Claus feed containing 30 50% H 2 S is presented alongside detailed analysis of species compositions in the thermal section. An increase in fuel gas flow rate (from 0 to 200 kmol/h) increased aromatics production in the furnace for lean acid gases. For rich acid gas, a decrease in aromatics production occurred as fuel gas flow rates was increased. The divergent trends were found to be occurring due to the reduced reactivity of methane in comparison to H 2 S at low flame temperatures, the dilution effect of unburnt CH 4 CO 2 and N 2 in the furnace, and the endothermic hydrocarbon pyrolysis reactions leading to aromatics formation and growth. Fuel gas addition also led to COS and CS 2 formation to reduce sulfur yield. The results indicate that fuel gas may not be the best solution for aromatics destruction in the Claus process for lean acid gas feeds.

title: Modeling and optimization of an industrial Claus process: Thermal and catalytic section
abstract: The main goal of this research is modeling and optimization of an industrial modified Claus process to achieve maximum sulfur recovery. The modified Claus process consists thermal conversion in furnace and catalytic conversion in two series fixed bed reactors. The furnace and catalytic reactors are modeled based on the mass and energy conservation laws at steady state condition. To prove the accuracy of the developed mathematical model, simulation results of conventional process are compared with the available plant data. Then, the optimal condition of Claus process is calculated considering sulfur recovery as the objective function using Genetic algorithm as a useful method in global optimization. The attainable decision variables are inlet temperature of furnace and fixed bed reactors, feed distribution along the furnace and flow rate of air in the furnace. The simulation results show that sulfur recovery is improved about 4.63% in the optimized process compared to the conventional process. In addition, performance of auto thermal reactor as a substitute for conventional adiabatic reactors is investigated to enhance sulfur recovery and reducing sulfur contaminants emission in the Claus process.

title: The ionic liquid mediated Claus reaction: a highly efficient capture and conversion of hydrogen sulfide
abstract: Ionic liquids (ILs) were demonstrated to be highly efficient media for the liquid phase Claus reaction. The reaction of H2S with SO2 in ILs proceeds very fast and almost completely to result in solid sulfur (S8) under mild conditions without the addition of any catalysts. Various ILs with different cations and anions were investigated and a simple IL 1 hexyl 3 methylimidazolium chloride [hmim][Cl] was found to be the most effective for the capture and conversion of H2S. It enables the transformation of H2S to S8 with a conversion ratio as high as >96% within 3 min. This finding opens up a promising method for the capture and conversion of H2S from gas streams.

title: Kinetic modeling and optimization of Claus reaction furnace
abstract: Optimization of Claus sulfur recovery plants requires a reliable kinetic model to describe the reaction furnace and waste heat boiler. In order to develop a suitable kinetic model for prediction of reaction furnace and waste heat boiler effluents, several reaction schemes were tested and the best reaction set was selected. The kinetic parameters of the best reaction scheme were optimized and different reactor networks were analyzed using the optimum reaction set. The modified model results were in good agreement with the experimental measured plant data both before and after waste heat boiler (The mean absolute errors were 7.62% and 7.88% respectively) In addition, the effects of increasing ammonia and oxygen content of feed, and air to acid gas ratio on reaction furnace effluents were investigated through various case studies. An optimization study was performed to control the operating variables of an operating sulfur recovery unit in order to obtain optimum conditions (including maximum reaction furnace temperature) maintain H2S to SO2 ratio at constant 2 and lower COS emissions from waste heat boiler.

title: Effects of H2O in the Feed of Sulfur Recovery Unit on Sulfur Production and Aromatics Emission from Claus Furnace
abstract: An increase in the exploitation of sour reservoirs with a high content of acid gas (mainly H2S and CO2) and the enforcement of stringent emission standards have triggered demand for high sulfur recovery efficiency in sulfur recovery units (SRUs) The high amount of H2O that is present in feed gases to the SRU can act as a diluent in the thermal section of the SRU and can also pose operational difficulties and have substantial chemical effect on the equilibrium limited reactions of sulfur production and the destruction of impurities. This paper explores the role of H2O (0 12% in the furnace feed) in sulfur recovery and in the fate of undesirable aromatics, COS, and CS2 in the thermal section using a detailed reaction mechanism and industrial SRU operating parameters. An increasing H2O concentration in the feed decreased the sulfur recovery efficiency in the thermal section significantly, as the equilibrium conversion of H2S to sulfur was affected. The higher H2O concentrations increased the concentrations