ABSTRACT A Process Analytical Technology (PAT) compliant unit (acronym PATOV) was designed for on... more ABSTRACT A Process Analytical Technology (PAT) compliant unit (acronym PATOV) was designed for online monitoring of Clean-in-Place (CIP) processes used in the pharmaceutical and food industry. The PATOV unit tends to significantly optimize CIP processes by online monitoring Total Organic Carbon (TOC) equivalent contaminations in the CIP off-stream to increase the efficiency and the quality of the cleaning process. The data will be used for an online control of the process to ensure optimal cleaning in minimized time. This will certainly allow for extensive savings of energy, water, and cleaning agents. Commercially available TOC analyzers qualified for the purpose require several minutes to provide a reliable TOC result. By implementing a mid-IR laser absorption technology, more precise a sensor based on an External Cavity-Quantum Cascade Laser (EC-QCL), the necessary information can be gained within seconds. An experimental CIP pilot plant was installed to reproduce CIP procedures by cleaning a vessel of a typical size used in pharmaceutical production processes. A continuous sample flow is gathered from the CIP offstream and fed into the PATOV unit which is placed close to the CIP pilot plant. The contamination of the CIP process water can be measured with a time resolution down to one second. The retention time of contaminations from the CIP pilot plant to the PATOV unit was minimized to <10 s by the design of an optimized sampling system. Currently, the TOC can be detected within the short timelines mentioned for single contaminants down to a concentration of e.g. 20 ppm for glycerol. Provided that the detection of lower concentrations and the calibration for other model contaminants, such as xanthan and proteins can be achieved, the PATOV unit has a high potential to improve the efficiency and the quality of CIP processes in the pharmaceutical and food industry.
In the present work chemical-oxidative scrubbing as a novel method for the desulphurisation of ra... more In the present work chemical-oxidative scrubbing as a novel method for the desulphurisation of raw biogas is presented with a special focus on the process potentials and economics. The selective absorption of hydrogen sulphide from gas streams containing high amounts of carbon dioxide using caustic solutions is not trivial but has been treated in literature. However, the application of this method to biogas desulphurisation has not been established so far. Based on rigorous experimental work, an industrial-scale pilot plant has been designed, erected and commissioned at a biogas plant with biogas upgrading and gas grid injection in Austria. Data collected from the 12-month monitored operation has been used to elaborate performance as well as economic parameters for the novel desulphurisation method. The proposed technology offers significant operational advantages regarding the degree of automation and the flexibility towards fluctuations in process boundary conditions. Furthermore, the economic assessment revealed the high competitiveness of the chemical-oxidative scrubbing process compared with other desulphurisation technologies with the named advantageous operational behaviour.
Membrane gas permeation using glassy membranes proved to be a suitable method for biogas upgradin... more Membrane gas permeation using glassy membranes proved to be a suitable method for biogas upgrading and natural gas substitute production on account of low energy consumption and high compactness. Glassy membranes are very effective in the separation of bulk carbon dioxide and water from a methane-containing stream. However, the content of hydrogen sulfide can be lowered only partially. This work employs process modeling based upon the finite difference method to evaluate a hybrid membrane system built of a combination of rubbery and glassy membranes. The former are responsible for the separation of hydrogen sulfide and the latter separate carbon dioxide to produce standard-conform natural gas substitute. The evaluation focuses on the most critical upgrading parameters like achievable gas purity, methane recovery and specific energy consumption. The obtained results indicate that the evaluated hybrid membrane configuration is a potentially efficient system for the biogas processing tasks that do not require high methane recoveries, and allows effective desulfurization for medium and high hydrogen sulfide concentrations without additional process steps.
ABSTRACT Die Ermittlung verlsslicher Phasengleichgewichtsinformationen gehört zu den wichtigsten ... more ABSTRACT Die Ermittlung verlsslicher Phasengleichgewichtsinformationen gehört zu den wichtigsten Problemstellungen der Mischphasenthermodynamik. Neben den klassischen Verfahren gewinnen quantenchemische a-priori-Methoden, die ohne experimentell angepasste Parameter auskommen, immer mehr an Bedeutung. In dieser Arbeit soll die Anwendbarkeit einer solchen Methode – COSMO-RS – für die Berechnung der in Trenntechnik und Umwelttechnik relevanten physikalischen Gaslöslichkeit beurteilt werden.
ABSTRACT A Process Analytical Technology (PAT) compliant unit (acronym PATOV) was designed for on... more ABSTRACT A Process Analytical Technology (PAT) compliant unit (acronym PATOV) was designed for online monitoring of Clean-in-Place (CIP) processes used in the pharmaceutical and food industry. The PATOV unit tends to significantly optimize CIP processes by online monitoring Total Organic Carbon (TOC) equivalent contaminations in the CIP off-stream to increase the efficiency and the quality of the cleaning process. The data will be used for an online control of the process to ensure optimal cleaning in minimized time. This will certainly allow for extensive savings of energy, water, and cleaning agents. Commercially available TOC analyzers qualified for the purpose require several minutes to provide a reliable TOC result. By implementing a mid-IR laser absorption technology, more precise a sensor based on an External Cavity-Quantum Cascade Laser (EC-QCL), the necessary information can be gained within seconds. An experimental CIP pilot plant was installed to reproduce CIP procedures by cleaning a vessel of a typical size used in pharmaceutical production processes. A continuous sample flow is gathered from the CIP offstream and fed into the PATOV unit which is placed close to the CIP pilot plant. The contamination of the CIP process water can be measured with a time resolution down to one second. The retention time of contaminations from the CIP pilot plant to the PATOV unit was minimized to <10 s by the design of an optimized sampling system. Currently, the TOC can be detected within the short timelines mentioned for single contaminants down to a concentration of e.g. 20 ppm for glycerol. Provided that the detection of lower concentrations and the calibration for other model contaminants, such as xanthan and proteins can be achieved, the PATOV unit has a high potential to improve the efficiency and the quality of CIP processes in the pharmaceutical and food industry.
In the present work chemical-oxidative scrubbing as a novel method for the desulphurisation of ra... more In the present work chemical-oxidative scrubbing as a novel method for the desulphurisation of raw biogas is presented with a special focus on the process potentials and economics. The selective absorption of hydrogen sulphide from gas streams containing high amounts of carbon dioxide using caustic solutions is not trivial but has been treated in literature. However, the application of this method to biogas desulphurisation has not been established so far. Based on rigorous experimental work, an industrial-scale pilot plant has been designed, erected and commissioned at a biogas plant with biogas upgrading and gas grid injection in Austria. Data collected from the 12-month monitored operation has been used to elaborate performance as well as economic parameters for the novel desulphurisation method. The proposed technology offers significant operational advantages regarding the degree of automation and the flexibility towards fluctuations in process boundary conditions. Furthermore, the economic assessment revealed the high competitiveness of the chemical-oxidative scrubbing process compared with other desulphurisation technologies with the named advantageous operational behaviour.
Membrane gas permeation using glassy membranes proved to be a suitable method for biogas upgradin... more Membrane gas permeation using glassy membranes proved to be a suitable method for biogas upgrading and natural gas substitute production on account of low energy consumption and high compactness. Glassy membranes are very effective in the separation of bulk carbon dioxide and water from a methane-containing stream. However, the content of hydrogen sulfide can be lowered only partially. This work employs process modeling based upon the finite difference method to evaluate a hybrid membrane system built of a combination of rubbery and glassy membranes. The former are responsible for the separation of hydrogen sulfide and the latter separate carbon dioxide to produce standard-conform natural gas substitute. The evaluation focuses on the most critical upgrading parameters like achievable gas purity, methane recovery and specific energy consumption. The obtained results indicate that the evaluated hybrid membrane configuration is a potentially efficient system for the biogas processing tasks that do not require high methane recoveries, and allows effective desulfurization for medium and high hydrogen sulfide concentrations without additional process steps.
ABSTRACT Die Ermittlung verlsslicher Phasengleichgewichtsinformationen gehört zu den wichtigsten ... more ABSTRACT Die Ermittlung verlsslicher Phasengleichgewichtsinformationen gehört zu den wichtigsten Problemstellungen der Mischphasenthermodynamik. Neben den klassischen Verfahren gewinnen quantenchemische a-priori-Methoden, die ohne experimentell angepasste Parameter auskommen, immer mehr an Bedeutung. In dieser Arbeit soll die Anwendbarkeit einer solchen Methode – COSMO-RS – für die Berechnung der in Trenntechnik und Umwelttechnik relevanten physikalischen Gaslöslichkeit beurteilt werden.
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