In the pulp and paper and biofuel industries, real-time online characterization of biomass gross calorific value is of critical importance to determine its quality and price and for process ...optimization. Near infrared spectroscopy is a relatively low-cost technology that could potentially be used for such an application. However, the near infrared spectra are also influenced by biomass temperature and moisture content. In this study, external parameter orthogonalization is employed to remove simultaneously the influence of temperature and moisture content on the spectra before predicting gross calorific value. External parameter orthogonalization is of particular interest when one desires to transfer information from one modeling experiment to another, such as when developing a calibration model for a new property from the same material, or when it would be more efficient to divide the experimental effort. External parameter orthogonalization (EPO) was found to be an effective method for desensitizing a partial least squares calibration model to the influence of temperature and moisture content, enabling robust and accurate prediction of biomass gross calorific value. Partial least square models developed with external parameter orthogonalization always provided equal or better performance than models developed without external parameter orthogonalization. The paper shows that experimental efforts and costs can be reduced by approximately one half while maintaining prediction accuracy and model robustness.
The use of a voltammetric electronic tongue as tool for the prediction of concentration levels of certain water quality parameters from influent and effluent wastewater from a Submerged Anaerobic ...Membrane Bioreactor pilot plant applied to domestic wastewater treatment is proposed here. The electronic tongue consists of a set of noble (Au, Pt, Rh, Ir, and Ag) and non-noble (Ni, Co and Cu) electrodes that were housed inside a stainless steel cylinder which was used as the body of the electronic tongue system. As a previous step an electrochemical study of the response of the ions sulphate, orthophosphate, acetate, bicarbonate and ammonium was carried out in water using the electrodes contained in the electronic tongue. The second part of the work was devoted to the application of the electronic tongue to the characterization of the influent and effluent waters from the wastewater treatment plant. Partial Least Squares analysis was used to obtain a correlation between the data from the tongue and the pollution parameters measured in the laboratory such as soluble chemical oxygen demand (CODs), soluble biological oxygen demand (BODs), ammonia (NH4–N), orthophosphate (PO4–P), Sulphate (SO4–S), acetic acid (HAC) and alkalinity (Alk). A total of 28 and 11 samples were used in the training and the validation steps, respectively, for both influent and effluent water samples. The electronic tongue showed relatively good predictive power for the determination of BOD, COD, NH4–N, PO4–P, SO4–S, and Alk.
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► A voltammetric electronic tongue is used as tool for the determination of water quality parameters. ► The electronic tongue consists of simple noble and non-noble electrodes. ► The electronic tongue displayed a relatively good predictive behaviour.
The available on‐line and in‐line sensor technologies developed for polymerization reactors from 1990 until today are discussed and critically reviewed. About 600 references are included, which ...evidence the growth in sensor technology in the last two decades. Sensors for operational parameters in polymer reactors (i.e. temperature, pressure, level and flow) as well as sensors for polymer property monitoring (i.e. calorimetry, chromatography and spectroscopy, among others) are included. Complementary topics such as state estimation, multivariate statistical methods, fault diagnosis techniques and optimal sensor selection and location are briefly covered.
On‐line and in‐line sensors are nowadays an essential part in the monitoring of polymerizations. They must be the result of an interdisciplinary effort from engineering, physics, chemistry and biology with signal processing in order to accurately and selectively measure minute changes in physico‐chemical variables. The available on‐line and in‐line sensor technologies developed for polymerization reactors from 1990 until today are discussed and critically reviewed. About 600 references are provided.
The global demand for complex biopharmaceuticals like recombinant proteins, vaccines, or viral vectors is steadily rising. To further improve process productivity and to reduce production costs, ...process intensification can contribute significantly. The design and optimization of perfusion processes toward very high cell densities require careful selection of strategies for optimal perfusion rate control. In this chapter, various options are discussed to guarantee high cell-specific virus yields and to achieve virus concentrations up to 10
virions/mL. This includes reactor volume exchange regimes and perfusion rate control based on process variables such as cell concentration and metabolite or by-product concentration. Strategies to achieve high cell densities by perfusion rate control and their experimental implementation are described in detail for pseudo-perfusion or small-scale perfusion bioreactor systems. Suspension cell lines such as MDCK, BHK-21, EB66
, and AGE1.CR.pIX
are used to exemplify production of influenza, yellow fever, Zika, and modified vaccinia Ankara virus.
The pursuit of fully autotrophic nitrogen removal via the anaerobic ammonium oxidation (anammox) pathway has led to an increased interest in carbon removal technologies, particularly the A-stage of ...the adsorption/bio-oxidation (A/B) process. The high-rate operation of the A-stage and lack of automatic process control often results in wide variations of chemical oxygen demand (COD) removal that can ultimately impact nitrogen removal in the downstream B-stage process. This study evaluated the use dissolved oxygen (DO) and mixed liquor suspended solids (MLSS) based automatic control strategies through the use of in situ on-line sensors in the A-stage of an A/B pilot study. The objective of using these control strategies was to reduce the variability of COD removal by the A-stage and thus the variability of the effluent C/N. The use of cascade DO control in the A-stage did not impact COD removal at the conditions tested in this study, likely because the bulk DO concentration (>0.5 mg/L) was maintained above the half saturation coefficient of heterotrophic organisms for DO. MLSS-based solids retention time (SRT) control, where MLSS was used as a surrogate for SRT, did not significantly reduce the effluent C/N variability but it was able to reduce COD removal variation in the A-stage by 90%.
A description of a system, developed for the condition monitoring of wind turbines, which combines innovative, real time, and on-line oil sensor technologies is described. The system integrates the ...measurement of the three main parameters that assess the status of the lubricating oil in the lubrication system using different technologies: the degree of oil degradation using visible absorbance spectroscopy; the water content using near infrared spectroscopy; and the presence of wear debris using image processing technology. The measuring principles, sensor integration and validation test results obtained in artificially degraded oil samples are presented.
Aerobic granulation from floccular sludge is difficult to detect in first stages with the naked eye. This work proposes a combination of multi-way principal components and case-based reasoning to ...predict the granulation state of a sequencing batch reactor, based solely on the on-line registered profiles of common sensors (i.e. pH, dissolved oxygen and oxidation-reduction potential). The methodology is able to discriminate between two active sludge granularities (floccular and granular). Two different scenarios are presented: one in which both granularities are present, and another scenario for which the granular state is not initially available. Analysis reported pH as the key variable in the transition between both states according to its variation, and that, in general, the granularity of the process can be correctly predicted at the end of the anaerobic phase. This methodology improves process monitoring capabilities during granulation and is an on-line alternative to a microscope analysis before the batch release.
Ultrasonic monitoring of food freezing Sigfusson, Halldor; Ziegler, Gregory R.; Coupland, John N.
Journal of food engineering,
05/2004, Letnik:
62, Številka:
3
Journal Article
Recenzirano
The time of flight of an ultrasonic pulse moving parallel to the direction of heat flux was measured in blocks of food (gelatin, chicken, beef) during freezing. Echoes were recorded from the food ...surfaces and from the moving ice front within the food. The changing return times of these echoes were used to calculate the percentage of the food frozen as a function of time either from the measured position of the ice front or by assuming the overall time of flight of the acoustic pulse was the sum of times spent traveling through a frozen and unfrozen phase. Both methods are predicated on the observation that for foods the change in speed of sound on freezing is much greater than the changes with respect to temperature in the absence of a phase change. Both methods gave reasonable prediction of the time for complete freezing as measured by thermocouples but the latter was more practical as the ice front was difficult to measure as the muscle foods became increasingly frozen.
This paper details a dynamic evaluation of a 1 m3 fixed bed anaerobic digestion reactor in response to organic overloads and toxicant shock loads. Raw industrial wine distillery wastewater was used ...as a reference substrate and several disturbances were applied to the process: (i) organic overloads with and without pH regulation in the feeding line, (ii) adding of ammonia in the input wastewater. The purpose of this study was to assess, using on-line instrumentation, the robustness of a fixed bed anaerobic digester. Anaerobic digestion processes have the reputation of being difficult to operate and prone to process instability due to external disturbances and the objective of this study was to demonstrate the possibility of such a reactor configuration for industrial use.
Continuous monitoring of water quality creates huge amounts of data and therefore requires new concepts to guarantee high data quality and to prevent data graveyards. Monitoring stations commonly ...used in practice today suffer from insufficient flexibility and a lack of standardization. That is, although a lot of monitoring tasks are comparable and should lead to robust and powerful platforms, most monitoring stations are case specific developments. In this paper the underlying ideas of a new generation of monitoring networks is described. First a problem analysis of monitoring stations typically seen in current river monitoring practice is outlined, then the monEAU vision on monitoring networks will be discussed together with an overview of a planned system set-up with innovative data evaluation concept.
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