Search results for: spinning fluids reactor
-
Assessment of wastewater quality indicators for wastewater treatment influent using an advanced logistic regression model
PublicationInfluent quality indicators play a significant role in wastewater treatment plant performance due to their correlation with reactor operations and effluent quality. However, selecting a specific/best parameter indicator for predicting influent wastewater quality is one of the challenges in wastewa- ter treatment. This study, therefore, focused on determining suitable variables as influent quality indicators. For this purpose, a...
-
A robust sliding mode observer for non-linear uncertain biochemical systems
PublicationA problem of state estimation for a certain class of non-linear uncertain systems has been addressed in this paper. In particular, a sliding mode observer has been derived to produce robust and stable estimates of the state variables. The stability and robustness of the proposed sliding mode observer have been investigated under parametric and unstructured uncertainty in the system dynamics. In order to ensure an unambiguous non-linear...
-
Neural modelling of dynamic systems with time delays based on an adjusted NEAT algorithm
PublicationA problem related to the development of an algorithm designed to find an architecture of artificial neural network used for black-box modelling of dynamic systems with time delays has been addressed in this paper. The proposed algorithm is based on a well-known NeuroEvolution of Augmenting Topologies (NEAT) algorithm. The NEAT algorithm has been adjusted by allowing additional connections within an artificial neural network and...
-
Laboratory research on the influence of swelling clay on the quality of borehole cementing and evaluation of clay-cutting wellbore tool prototype
PublicationSwelling clay phenomenon is frequently observed during oil and gas drilling operations and has a significant impact on the quality of cementing procedure. Certain types of clayey minerals increase their volume in contact with water-based drilling fluids. After drilling is completed, borehole remains unsupported and filled with waterbased drilling fluids for several hours, before a casing string is inserted and secured with cement....
-
Effects of Addictive Substances During Pregnancy and Infancy and Their Analysis in Biological Materials
PublicationThe use of addictive substances during pregnancy is a serious social problem, not only because of effects on the health of the woman and child, but also because drug or alcohol dependency it detracts from childcare and enhances the prospect of child neglect and family breakdown. Developing additive substance abuse treatment programs for pregnant women is socially important and can help ensure the health of babies, prevent subsequent...
-
Metody oczyszczania odcieków z procesów przeróbki osadów w komorach fermentacji
PublicationOdcieki z beztlenowych procesów przeróbki osadu w komorach fermentacji (tzw. wody poosadowe) są istotnym źródłem azotu dopływającego do części biologicznej oczyszczalni ścieków. Odpowiednie oczyszczanie tych wód może więc, w bardzo istotny sposób wpłynąć na warunki eksploatacji oczyszczalni. Konwencjonalny proces usuwania amoniaku za pomocą dwóch faz, tj. nitryfikacji i denitryfikacji, są coraz częściej zastępowane przez jednoetapowy...
-
„Eulerian – Eulerian” versus ,,Eulerian –Lagrangean” models of condensation
PublicationLiquid phase in the flowing vapor through stages of the steam turbine is the cause of a lot of failures. Nowadays, due to work of steam turbines at partial load, process of homogeneous and heterogeneous condensation still is current. The formation of drops of condensate under conditions other than nominal operation of turbine is a process still unknown. Engineers and designers involved in the development of power station machines...
-
Comparison of heat transfer characteristics in surface cooling with boiling microjets of water, ethanol and HFE7100
PublicationThe basis of microjet technology is to produce jets which impinge the surface at the stagnation point with a very high kinetic energy. Main objective of this paper was to investigate the physical phenomena occurring on solid surfaces upon impingement of the single microjet in case of three fluids, namely water, ethanol and HFE7100. Intense heat transfer in the impact zone of microjet has been examined and described with precise...
-
Criteria for selection of working fluid in low-temperature ORC
PublicationThe economics of an ORC system is strictly linked to thermodynamic properties of the working fluid. A bad choice of working fluid could lead to a less efficient and expensive plant/generation unit. Some selection criteria have been put forward by various authors, incorporating thermodynamic properties, provided in literature but these do not have a general character. In the paper a simple analysis has been carried out which resulted...
-
EFFECT OF NANOFLUID CONCENTRATION ON TWO-PHASE THERMOSYPHON HEAT EXCHANGER PERFORMANCE
PublicationAn approach – relaying on application of nanofluid as a working fluid, to improve performance of the two-phase thermosyphon heat exchanger (TPTHEx) has been proposed. The prototype heat exchanger consists of two horizontal cylindrical vessels connected by two risers and a downcomer. Tube bundles placed in the lower and upper cylinders work as an evaporator and a condenser, respectively. Distilled water and nanofluid water-Al2O3...
-
Pressure drop and heat transfer during boiling and condensation at subcritical region
PublicationMost of the data presented in the literature relate to saturation temperatures in the range - 20°C to 40°C due to the application in refrigeration technology. There is necessity to extend databases to higher values of saturation temperature due to new applications such as Organic Rankine Cycle and high temperature heat pumps. Only few papers contain data for high reduced pressure for low boiling point liquids. This paper focus...
-
Transport of paracetamol in swellable and relaxing polyurethane nanocomposite hydrogels
PublicationPolyurethane hydrogels are potentially attractive materials for biomedical applications. They are able to absorb large amount of water, biological fluids or active substances, and thus, they have potential to be used as absorbents or wound-healing dressings. They are also used for the controlled release of therapeutics because of their capacity to embed biologically active agents in their water-swollen network. The presence of...
-
Application of Eco-innovative Technologies of Nutrients Removal in Wastewater – Case Study BARITECH Project
PublicationEco-innovative technologies in wastewater treatment should provide not only stringent standards for the quality of treated wastewater but also ensure maximum recovery of energy and raw materials from wastewater. One of the ways to improve the removal efficiency of nitrogen and phosphorus compounds in existing conventional wastewater treatment plants is pretreatment of reject water generated during the mechanical...
-
Symulator szybkich procesów dynamiki reaktora jądrowego wodno ciśnieniowego
PublicationArtykuł przedstawia symulator dynamiki reaktora jądrowego (RJ) zbudowany w oparciu o punktowe modele matematyczne procesów reaktora typu wodnego ciśnieniowego (ang. Pressurized Water Reactor – PWR) i zaimplementowany w środowisku MATLAB/Simulink. Symulator wykorzystywany jest obecnie jako narzędzie pomocne w dydaktyce i wstępnych badaniach w zakresie energetyki jądrowej na Politechnice Gdańskiej. W pierwszej części artykuł Autorzy...
-
Comparison of state feedback and PID control of pressurizer water level in nuclear power plant
PublicationThe pressurizer water level control system in nuclear power plant with pressurized water reactor (PWR) is responsible for coolant mass balance. The main control goal is to stabilize the water level at a reference value and to suppress the effect of time-varying disturbances (e.g. coolant leakage in primary circuit pipeline system). In the process of PWR power plant operation incorrect water level may disturb pressure control or...
-
Studies on the utilization of post-distillation liquid from Solvay process to carbon dioxide capture and storage
PublicationIn this work, a method of precipitated calcium carbonate production from the post-distillation liquid created in the Solvay process and waste carbon dioxide was proposed and investigated. Precipitation was carried out in a model solution of calcium chloride containing ammonia at various molar ratios in relation to Ca2+ ions, while gaseous carbon dioxide was supplied to the reactor as a pure gas or as a mixture with air. It was...
-
Recent advances in hydrodynamic cavitation-based pretreatments of lignocellulosic biomass for valorization
PublicationRecently, the hydrodynamic cavitation (HC)-based pretreatment has shown high effectiveness in laboratories and even in industrial productions for conversion of lignocellulosic biomass (LCB) into value-added products. The pretreatment capability derives from the extraordinary conditions of pressures at ∼500 bar, local hotspots with ∼5000 K, and oxidation (hydroxyl radicals) created by HC at room conditions. To promote this emerging...
-
Adaptive stochastic and hybrid nonlinear optimization algorithms for improving the effectiveness of the biological processes at WWTP
PublicationWastewater treatment plays an important factor in the modern world. Insufficient treatment may result in environmental pollution which can further lead to disasters and diseases. However, processes that take place inside wastewater treatment plants (WWTP) are highly complex in nature, therefore it is difficult to design an efficient, optimal control system. The problem regarding biochemical reactions inside Sequential Batch Reactor...
-
An observability and detectability analysis for non-linear uncertain CSTR model of biochemical processes
PublicationThe problem of proving observability/detectability properties for selected non-linear uncertain model of biochemical processes has been addressed in this paper. In particular, the analysis of observability/detectability in the face of parametric and unstructured uncertainty in system dynamics transformed into unknown inputs, and unknown initial conditions has been performed. Various sets of system measured outputs were taken into...
-
PRESSURE DROP OF HFE7000 AND HFE7100 IN FLOW CONDENSATION IN MINICHANNELS WITH ACCOUNT OF NON-ADIABATIC EFFECTS
PublicationFlow boiling and flow condensation are often regarded as two opposite or symmetrical phenomena involving the change of phase. There is a temptation to describe both these phenomena with one only correlation. From amongst the structures present in flow boiling and flow condensation at least the annular flow structure seems to be mostly appropriate to the common modeling. However, the shear stress acting between vapor phase and liquid...
-
Comparitive study of heat transfer and pressure drop during flow boiling and flow condensation in minichannels
PublicationIn the paper a method developed earlier by authors is applied to calculations of pressure drop and heat transfer coefficient for flow boiling and also flow condensation for some recent data collected from literature for such fluids as R404a, R600a, R290, R32,R134a, R1234yf and other. The modification of interface shear stresses between flow boiling and flow condensation in annular flow structure are considered through incorporation...
-
Magneto-thermal convection of low concentration nanofluids
PublicationThe main aim of this paper was to analyze possible utilization of the low concentration nanofluids and the magnetic field to enhance heat transfer. The studied fluids were based on water with an addition of copper particles (40-60 nm diameter). They belonged to the diamagnetic group of materials. As a first attempt to stated target the analysis of enclosure placed in the maximal value of square magnetic induction gradient was carried...
-
Hydrogen production from biomass using dark fermentation
PublicationHydrogen applicability in the power, chemical and petrochemical industries is constantly growing. Efficientmethods of hydrogen generation from renewable sources, including waste products, are currently being de-veloped, even though hydrogen is mainly produced through steam reforming or thermal cracking of natural gasor petroleum fractions. In paper alternative methods of hydrogen production with a particular emphasis on darkfermentation...
-
Current harmonic controller in multiple reference frames for series active power filter integrated with 18-pulse diode rectifier
PublicationThe paper presents the control system and selected results of experimental tests of the AC/DC power converter consisting of an 18-pulse diode rectifier based on coupled reactors and a serial active power filter. Proportional integral controllers with decoupling components are implemented in multiple reference frames for selective line current harmonic suppression. The regulator is provided with a backtracking anti-windup mechanism...
-
Ammonia amendment promotes high rate lactate production and recovery from semi-continuous food waste fermentation
PublicationIn this study, a reliable approach using ammonia nitrogen was proposed to increase lactate production during semi-continuous food waste (FW) fermentation under mesophilic conditions. Both free ammonia nitrogen (FAN) and ammonium ion (NH4+-N) were present in mesophilic reactors, with a wide FAN/NH4+-N ratio variation due to the intermittent pH control. The investigation of responsible mechanisms revealed that the increased production...
-
Waste Tyres Pyrolysis for Obtaining Limonene
PublicationThis review deals with the technologies of limonene production from waste tyre pyrolysis. Thermal decomposition is attractive for tackling the waste tyre disposal problem, as it enables both: energy to be recovered and limonene to be obtained. This material management recycling of tyres is environmentally more beneficial than the burning of all valuable products, including limonene. Given this recoverability of materials from waste...
-
Activation of peroxymonosulfate using carbon black nano-spheres/calcium alginate hydrogel matrix for degradation of acetaminophen: Fe3O4 co-immobilization and microbial community response
PublicationHerein, we focused on the degradation of acetaminophen (ACT) drug in liquid phase by peroxymonosulfate (PMS) activated by carbon black nano-spheres (CBNS). The nanostructured activator was immobilized into calcium alginate hydrogel matrix (CAHM) to avoid the washout of the fine nanostructures. The Langmuir modeling showed an insignificant contribution to the adsorption process in the removal of ACT. The basic pH conditions favored...
-
An automatic selection of optimal recurrent neural network architecture for processes dynamics modelling purposes
PublicationA problem related to the development of algorithms designed to find the structure of artificial neural network used for behavioural (black-box) modelling of selected dynamic processes has been addressed in this paper. The research has included four original proposals of algorithms dedicated to neural network architecture search. Algorithms have been based on well-known optimisation techniques such as evolutionary algorithms and...
-
Novel hierarchical nonlinear control algorithm to improve dissolved oxygen control in biological WWTP
PublicationWastewater treatment is a problem known to humankind for centuries. The quality of treated sewage determines the condition of reservoirs around the world. Control of such a complex and nonlinear system as a wastewater treatment plant requires thorough knowledge of the process. The paper presents a hierarchical control system of a Sequencing Batch Reactor (SBR) in Wastewater Treatment Plant (WWTP) taking into account a model based...
-
Negative carbon dioxide gas power plant integrated with gasification of sewage sludge
PublicationOne of the primary objectives of the negative carbon dioxide gas power plant (nCO2PP) is to develop an innovative technology confirming the possibility of the use of sewage sludge to produce electricity while having a positive impact on the environment. In this paper, a mathematical model is presented to estimate thermodynamic parameters of the system in relation to the gasification process and changes in such parameters in the...
-
Eksperymentalna analiza wpływu ruchu posuwisto-zwrotnego i obrotowego oraz miejscowych zmian geometrii na skuteczność wypierania cieczy wiertniczych z przestrzeni pierścieniowej
PublicationRozprawa przedstawia analizę wpływu ruchu kolumny rur stosowanego w wiertnictwie oraz miejscowych zmian geometrii przestrzeni pierścieniowej na skuteczność procesu wypierania się cieczy. Jest to pierwsze badanie w otwartej literaturze omawiające te czynniki, w którym opisano wyniki eksperymentów na dedykowanym stanowisku badawczym. W pracy omówiony został wpływ węglowodorów na współczesną cywilizację, jak również wpływ skuteczności...
-
WARUNKI REZONANSOWE W WĘŹLE Z KOMPENSATOREM SVC
PublicationInstalowanie kompensatorów statycznych w sieciach rozdzielczych i przesyłowych służy poprawie profili napięciowych. Kompensatory jako źródła mocy biernej zwiększają stabilność napięciową systemu. Pozwalają także na szybszą odbudowę systemu w przypadku awarii napięciowej. W artykule zaprezentowano wpływ struktury i wysterowania układu SVC na zmianę impedancji w układzie zasilania. Ma to bezpośredni wpływ na częstotliwości, przy...
-
Complex Corrosion Monitoring System for Crude Distillation Unit in Form of Neutral Network
PublicationComplex and successful corrosion monitoring of refinery processes can significantly reduce material losses and failure risk. The developed corrosion monitoring system is based on online ultrasonic sensors, ER (electrical resistance) probes, gravimetric method and multipoint analytical analysis of chemical composition of the fluids. Additional online LPR (linear polarization resistance) sensors controlling corrosiveness of sour...
-
Reliability and Validity of Optoelectronic Method for Biophotonical Measurements
PublicationReliability and validity of measurements is of utmost importance when assessing measuring capability of instruments developed for research. In order to perform an experiment which is legitimate, used instruments must be both reliable and valid. Reliability estimates the degree of precision of measurement, the extent to which a measurement is internally consistent. Validity is the usefulness of an instrument to perform accurate...
-
A mathematical model of rheological behavior of novel bio-based isocyanate-terminated polyurethane prepolymers
PublicationIn this paper, the results of rheological study on isocyanate-terminated polyurethane prepolymers, containing modified soybean oil residues incorporated into the chemical structure are described. Isocyanate-terminated prepolymers were synthesized from 4,4′-diphenylmethane diisocyanate and the mixture of hydroxylated soybean oil and commercial polyether. The measurements were performed by using rotary rheometer R/S-CPS+ (Brookfield,...
-
The new concept of capillary forces aided evaporator for application in domestic organic rankine cycle
PublicationThis paper presents studies on the possibility of applying capillary forces induced in the porous structure to a modern design of evaporator. The potential application of such heat exchanger is for example an evaporator of the domestic micro combined heat and power (CHP) unit. One of the problems in the micro-CHP is excessive demand for pumping power. The proposed design helps in overcoming that issue. In the evaporator outlined...
-
Utilisation of waste heat from the power plant by use of the ORC aided with bleed steam and extra source of heat
PublicationUtilization of waste heat recovered from the exhaust gases of the power generation unit by means of ORC (organic Rankine cycles) installation is considered. The waste heat is available in the form of a stream of hot water having temperature of 90 stC in the amount of 200 MWt. To increase evaporation temperaturę of ORC working fluid the heat of steam from the extraction points from the low-pressure part of steam turbine is used....
-
Parametric Study on a Performance of a Small Counter-Rotating Wind Turbine
PublicationA small Counter-Rotating Wind Turbine (CRWT) has been proposed and its performancehas been investigated numerically. Results of a parametric study have been presented in this paper.As parameters, the axial distance between rotors and a tip speed ratio of each rotor have been selected.Performance parameters have been compared with reference to a Single Rotor Wind Turbine (SRWT).Simulations were carried out with Computational Fluids...
-
Pre-analytical aspects in metabolomics of human biofluids – sample collection, handling, transport, and storage
PublicationMetabolomics is the field of omics research that offers valuable insights into the complex composition of biological samples. It has found wide application in clinical diagnostics, disease investigation, therapy prediction, monitoring of treatment efficiency, drug discovery, or in-depth analysis of sample composition. A suitable study design constitutes the fundamental requirements to ensure robust and reliable results from the...
-
Comparison of tuning procedures based on evolutionary algorithm for multi-region fuzzy-logic PID controller for non-linear plant
PublicationThe paper presents a comparison of tuning procedures for a multi-region fuzzy-logic controller used for nonlinear process control. This controller is composed of local PID controllers and fuzzy-logic mechanism that aggregates local control signals. Three off-line tuning procedures are presented. The first one focuses on separate tuning of local PID controllers gains in the case when the parameters of membership functions of fuzzy-logic...
-
Effects of Different Aeration Modes on Ammonia Removal from Sludge Digester Liquors in the Nitritation-Anammox Process
PublicationSludge digester liquors can be responsible for up to one third of the nitrogen load to the biological step of wastewater treatment plants (WWTPs). The conventional process for ammonia removal via two sequential processes, i.e. nitrification and denitrification, is increasingly being challenged by a one-step process in which ammonium is oxidized directly to nitrogen gas e.g. ammonium oxidation (anammox) process. In this novel process,...
-
Application of BDD thin film electrode for electrochemical decomposition of heterogeneous aromatic compounds
PublicationThe aim of the presented study is to investigate the applicability of electrochemical oxidation of aromatic compounds containing heteroatoms, e.g. waste from production of pesticides or pharmaceutics, at a borondoped diamond (BDD) electrode. The BDD electrodes were synthesized by microwave plasma enhanced chemical vapour deposition (MW PE CVD). Investigation of the electrode surface by optical microscopy and scanning electron microscopy...
-
Stone cutting industry waste-supported zinc oxide nanostructures for ultrasonic assisted decomposition of an anti-inflammatory non-steroidal pharmaceutical compound
PublicationPowdered stone waste (PSW) obtained from a stone cutting industrial unit was applied as support for the immobilization of nano-sized ZnO to be utilized as an effective catalyst for the catalytic conversion of acetaminophen (ACE) under ultrasonication. The incorporation of ZnO nanostructures into PSW structure enhanced the specific surface area and pore volume of the as-prepared nanocompound. The change in the value of zero point...
-
Visible-light-driven lanthanide-organic-frameworks modified TiO2 photocatalysts utilizing up-conversion effect
PublicationHighly efficient and quite stable composite with core-shell-like architecture reported herein, responds to the challenge of sunlight-driven photocatalysts. The Ln(ndc)/TiO2 photocatalytic system comprises active lanthanide-carboxylate coordination networks (Nd, Er, Ho, and Tm as metal ions, and 2,6-naphthalene dicar-boxylic acid as the organic linker) and inert titanium dioxide and allow to convert incompatible visible radiation...
-
Stochastic optimisation algorithm for optimisation of controller parameters for control of dissolved oxygen in wastewater treatment plant
PublicationWastewater treatment plants (WWTPs) are very important facilities for mankind. They enable the removal and neutralisation of man-made pollutants. Therefore, it is important for wastewater treatment plants to operate as efficiently as possible so that the level of pollutants in the treated wastewater meets specific requirements. This paper concerns the design of a hierarchical nonlinear adaptive control system for dissolved oxygen...
-
COMPARISON OF HEAT TRANSFER CHARACTERISTICS IN SURFACE COOLING WITH BOILING MICROJETS OF WATER, ETHANOL AND HFE7100
PublicationThe basis of microjet technology is to produce laminar jets which when impinging the surface have a very high kinetic energy at the stagnation point. Boundary layer is not formed in those conditions, while the area of film cooling has a very high turbulence resulting from a very high heat transfer coefficient. Applied technology of jet production can result with the size of jets ranging from 20 to 500μm in breadth and 20 to 100μm...
-
Experimental investigation of domestic micro-CHP based on the gas boiler fitted with ORC module
PublicationThe results of investigations conducted on the prototype of vapour driven micro-CHP unit integrated with a gas boiler are presented. The system enables cogeneration of heat and electric energy to cover the energy demand of household. The idea of such system is to produce electricity for own demand or for selling it to the electric grid – in such situation the system user will became the prosumer. A typical commercial gas boiler,...
-
Antibacterial properties of laser-encapsulated titanium oxide nanotubes decorated with nanosilver and covered with chitosan/Eudragit polymers
PublicationTo provide antibacterial properties, the titanium samples were subjected to electrochemical oxidation in the fluoride-containing diethylene glycol-based electrolyte to create a titanium oxide nanotubular surface. Afterward, the surface was covered by sputtering with silver 5 nm film, and the tops of the nanotubes were capped using laser treatment, resulting in an appearance of silver nanoparticles (AgNPs) of around 30 nm in diameter...
-
Galerkin Finite Element Process for Entropy Production and Thermal Evaluation of Third-Grade Fluid Flow: A Thermal Case Study
Publication: A fluid’s moving class improves its heat transmission capability, as well as its rigidity, owing to multivariate molecule suspension. In this way, nanofluids are superior to common fluids. In this study, we evaluated the features of ease and heat transfer. Furthermore, we investigated permeable media, heat source, variable heat conductivity, and warm irradiation results. A mathematical technique known as the Galerkin finite element...
-
Application of Thermo-chemical Technologies for Conversion of Associated Gas in Diesel-Gas Turbine Installations for Oil and Gas Floating Units
PublicationThe paper considers the issue of thermo-chemical recovery of engine’s waste heat and its further use for steam conversion of the associated gas for oil and gas floating units. The characteristics of the associated gas are presented, and problems of its application in dual-fuel medium-speed internal combustion engines are discussed. Various variants of combined diesel-gas turbine power plant with thermo-chemical heat recovery are...