High Pressure Steam Research Articles

Effect of jet-cooking on rheological properties of navy bean flour suspensions

Navy beans are a gluten-free pulse containing great heathy sources for human beings. In this work, we compared the rheological properties of untreated navy bean flour suspensions (UNBFS) and jet-cooked navy bean flour suspensions (JCNBFS). Jet-cooking is a direct-contact heating process employing high-temperature and high-pressure steam for producing food and beverage products. We found that the linear rheological properties of 8% (wt.%) UNBFS exhibited viscoelastic fluid behavior; while 10% (wt.%) UNBFS displayed viscoelastic fluid/solid cross-over behavior; but 12% (wt.%) UNBFS displayed weak viscoelastic solid behavior. Unlike UNBFS, all three (8%, 10%, and 12%) (wt.%) jet-cooked navy bean flour suspensions (JCNBFS) displayed linear rheological properties having viscoelastic solid gel-like behaviors. The rheological properties of JCNBFS were strongly dependent on the concentration of the suspensions. The non-linear viscoelastic properties of the three suspensions of UNBFS exhibited similar viscosity shear thinning behavior. The degree of shear thinning was slightly reduced both at very low and high shear rates. The non-linear rheological properties of the three suspensions of JCNBFS also displayed shear thinning behaviors. The viscosity curves of the JCNBFS were much steeper than those of the UNBFS. This demonstrates that JCNBFS possessed greater shear thinning capacity than UNBFS. Both linear and non-linear rheological property studies for UNBFS and JCNBFS revealed that jet-cooking processing alters the molecular structures of navy bean flours’ starch and proteins, which would influence the navy bean flour suspensions’ properties. The results of this work will be useful to develop new food products from navy beans.

Multiple utilities targeting in energy integration considering rigorous temperature-enthalpy relations

Energy integration is a strong concern in process synthesis. Most methods are applied with simplifying assumptions for better computational efficiency. Enthalpies are obtained considering constant heat capacities, which is coherent for some processes. However, for streams in near-critical or phase-changing conditions, enthalpy may vary in a strongly nonlinear form. This paper proposes an optimization approach using concepts from Pinch Analysis for utility and heat exchange area targeting considering process and utility stream heat capacity variations with temperature. Decision variables are heat recovery approach temperature (HRAT), final utility temperatures, and energy duties for each available utility. Three case studies were evaluated. Large differences in utility allocations were observed (e.g., in Example 1, for the rigorous cp case, no medium- or low-pressure steam is applied, while high-pressure steam heat duty is 2.32 times the value from the constant cp case). Processing times were reasonable for early design stages (around one minute).

Performance evaluation of a novel geothermal energy integrated single effect evaporator desalination with software simulation

Water desalination utilizing low-enthalpy geothermal fluid is a sustainable solution to the world's water shortage that has the potential to be integrated with thermal-based desalination technologies. This study presents a comprehensive method for the performance analysis of a geothermal combined single-effect evaporator without a steam jet ejector and a single-effect evaporator with a steam jet ejector for the production of 1 kg of fresh water per second. To build the geothermal combined single-effect evaporator system, we compared the outcomes of manual computations performed in Excel and MATLAB/Simulink. MATLAB/Simulink includes a Graphical User Interface (GUI) that allows users to generate block designs through click-and-drag mouse activities. Calculations performed manually, Excel or MTALB/Simulink, should all have the same value, with only a little variation. In this case, latent and sensible heat for seawater evaporation is supplied by low enthalpy geothermal heat employed as heating steam with a temperature of less than 130 °C. We focus on a wide range of characteristics to better understand the impact of design choices on evaluation findings. Some variables include heating steam temperature, boiling temperature, feed water salinity, and geothermal resource quality. The accuracy of the results of our fundamental model was assessed by adjusting their values. The simulation results show that using a low boiling temperature and a high motive steam pressure yields a greater PR.

Novel Reactive Distillation Process for Cyclohexyl Acetate Production: Design, Optimization, and Control.

A side-reactor column (SRC) configuration, comprising a vacuum column coupled with atmospheric side reactors, is proposed to overcome the thermodynamic restriction in the esterification of cyclohexene with acetic acid to produce cyclohexyl acetate. Meantime, this configuration can avoid the utilization of the high-pressure steam and provide enough zone for catalyst loading. In order to obtain the minimum total annual cost (TAC), the process is optimized by a mixed-integer nonlinear programming optimization method based on the improved bat algorithm. The results indicate that the optimized SRC configuration saves about 44.81% of the TAC compared to the reactive distillation process. Based on the optimized SRC process, dynamic control is carried out. The dual-point temperature and temperature-composition control structures are proposed to reject throughput and feed composition disturbances. The dynamic performances demonstrate that the temperature-composition control structure is better in maintaining product purity.

High-pressure steam treatment with Pt/TiO2 enhances the low temperature formaldehyde oxidation performance

A facile high-pressure steam treatment is developed to improve the formaldehyde oxidation performance of the typical Pt/TiO2 catalyst at low temperatures. The formaldehyde oxidation rate of the treated Pt/TiO2 catalyst can be increased by 4.8 times compared with that of the pristine one. Simultaneously, the treated Pt/TiO2 catalyst possesses the good catalytic stability and catalytic resistance to dry environment. The kinetic study shows that formaldehyde molecules are more liable to be oxidized on the treated Pt/TiO2. A series of characterization results display that the structural parameters of Pt and TiO2 treated with high-pressure steam are not altered. It is found that a layer of bound water is formed on the surface of Pt nanoparticles, which can modify some surface properties of treated Pt/TiO2 catalyst. The interaction strength of intermediates (e.g. CO) with Pt is significantly weakened. Moreover, the amounts of oxygen species and surface hydroxyl for HCHO oxidation are dramatically increased on the treated Pt/TiO2. Based on these characteristics, two reaction steps of formate and CO can be accelerated to enhance the low temperature HCHO oxidation performance of treated Pt/TiO2 catalyst according to the HCHO-DRIFTS studies.

Optimum Design of High-Temperature Steam Generator for Hydrogen Production Enhancement

In this study, an optimal design was proposed for the pressure drop of a high-temperature steam generator to enhance hydrogen production in a solid oxide electrolyzer cell (SOEC). The high-temperature steam generator (HTSG) was analyzed under experimental conditions of a steam temperature of 773 K, steam inlet pressure of 300–600 kPa, and steam flow rate of 10–35 kg/h. The pressure drop characteristics of the HTSG were analyzed under various variable conditions via a computational fluid dynamics simulation. The pressure drop according to the variable change was ranged from a minimum of 54 kPa (inlet nozzle angle: 25°) to a maximum of 309 kPa (body ratio: 0.63), and the valid range was 28,700 < Re < 306,600 . The hydrogen production capacity that can be produced utilizing the optimally designed HTSG was predicted to be up to 35.7 tons annually. In addition, CO2 emissions during hydrogen production under optimal conditions are 9.92 ton-CO2/ton-hydrogen, which can be reduced by up to 86.8% compared to the conventional high-temperature and high-pressure (HTHP) steam, thereby enhancing hydrogen production and energy harvesting.

Modeling of horizontal steam injection in a water pool

A comprehensive understanding of the direct contact condensation (DCC) phenomena of steam discharged into a subcooled water pool is essential for the nuclear engineering field. DCC is the most rapid and efficient way to condense high-pressure and high-temperature steam with simple engineering systems. However, the pressure oscillation due to the rapid condensation and small length and time scales of turbulent two-phase flow make the investigation of DCC phenomena challenging either by experiments or with numerical simulations.This paper presents the computational fluid dynamics (CFD) simulations of the small-scale separate effect test facility (SEF-POOL) experiment of Lappeenranta-Lahti University of Technology (LUT University). In the SEF-POOL test, the steam was injected using the orifice of a diameter of 16 mm. All simulations were performed by employing the compressible two-phase solver of OpenFOAM which was based on the Eulerian–Eulerian two-fluid approach. The interfacial heat transfer between steam and water was modeled by using the Nusselt number formulation of Coste (2004). The Rayleigh–Taylor interfacial (RTI) area model of Pellegrini et al. (2015) was applied for the interfacial area modeling. In this work, the formation and collapse of the steam bubbles are studied using the extended pattern recognition based image analysis algorithm. The pattern recognition (PR) algorithm is based on the video material recorded during the SEF-INF2 experiment of the SEF-POOL test facility.The presented study show that if the two-phase interface is rough and smear into the subgrid scale, the interfacial area density calculation solely with the volume fraction gradient is inadequate for predicting rapid condensation rates. Results indicate that rapid and high interfacial accelerations in DCC trigger interfacial instabilities which increased the interface roughness and total interfacial area consequently. Thus, interfacial area modeling with the RTI increased the total interfacial heat transfer rate in the simulations. The achieved results exhibit that the selected modeling approach captured the rapid bubbling condensation oscillation mode of the SEF-POOL test. Presented results demonstrate that image analysis and pattern recognition have great potential in thermal-hydraulic research that can be beneficial for direct contact condensation and phase-interface dynamics model development.

Garbage to Nanocellulose: Quantitative Isolation and Characterization of Steam-Treated Carboxymethyl Holocellulose Nanofibrils from Municipal Solid Waste

Municipal solid waste (MSW) is a major source of greenhouse gas emissions unless its carbons are sequestered into higher-value products. This study focuses on isolating organic solids and cellulose-rich fibers from MSW via high-pressure steam treatment and converting the fibrous, prepulped materials from wastepaper, packaging materials, cardboard, etc., into value-added cellulose nanofibrils. Chemical–mechanical defibrillation of steam-treated municipal solid waste was optimized using heterogeneous and nonregioselective carboxymethyl etherification coupled with shearing by blender, thus transforming a heterogeneous mix of MSW into homogeneous carboxymethyl holocellulose nanofibrils without the use of conventional pretreatments of crude cellulosic feedstock. These carboxymethylated, hemicellulose-coated, cellulose nanofibrils were isolated quantitatively at >95% yield with widths 3–8 nm, thicknesses 1–3 nm, and lengths up to 1000 nm. We posit that this advancement of combining an inexhaustible, global supply of waste cellulose, large-scale steam autoclaving pretreatment, and an industrially relevant carboxymethylation process could unlock the higher potential of sustainable cellulosic nanomaterials for a circular economy.

Long-Exposure Air and Steam Oxidation Characteristics of IN 617 Alloys

India’s growing power demands and emission norms require more efficient coal-based power plants. The shifting of power plants from subcritical to ultra-supercritical (USC) steam conditions could improve efficiency by 12% and reduce CO2 emissions by 35%. There is a need to develop and qualify materials under ultra-supercritical steam conditions with high temperatures and high pressures in laboratory scale. The sample materials were exposed to high temperatures of 700 °C under air and high pressure steam at 700 °C/243 bars for 1000 h in as-received and grain-boundary-enhanced conditions. Grain boundary enhancement included optimization of a thermo-mechanical process involving cold rolling and annealing of samples. The effect of air and steam oxidation on IN 617, a nickel-based candidate superalloy, was analysed. Steam oxidation was performed on a custom-built PARR 4650 series autoclave, and the oxidized samples were characterised under scanning electron microscopy, to evaluate the oxide scales. The grain-boundary-engineered material performed better than the as-received samples. IN 617 overall fared better under both air and steam conditions, with far less weight gains.

STRESS ANALYSIS EVALUATION AND PIPE SUPPORT TYPE ON HIGH-PRESSURE AND TEMPERATURE STEAM PIPE

The design and analysis of piping systems are critical in the power and process industries. The steam pipe is one of the main requirements for the plant to be installed. High-pressure and high-temperature steam pipes in the piping system are critical lines that need to be subjected to stress analysis. This study aims to evaluate the stress and the effect of using pipe supports on the stress in the piping system. Stress analysis is needed to ensure that the piping system that is designed is safe and does not exceed the allowable stress under operating conditions. Data analysis used ASTM A335-P11 as a pipe material with a design pressure of 65 bars and a design temperature of 480 °C. Stress analysis was carried out using CAESAR II software, which refers to ASME B31.3 process piping standards and codes. The findings revealed that the type of support chosen, such as the gap and distance of pipe support, has a significant impact on the stress value in the piping system. The results of the analysis are carried out several times to get the stress value so that it does not exceed the allowable stress. The greatest stress value occurs at the expansion load condition in the steam pipe system design. The chosen piping system design has a ratio of 93.6%, which is located at node 220 with a stress value of 35889.1 psi and an allowable stress of 38327.2 psi. Because the stress value that occurs is below the allowable stress, the steam pipe system is safe to be installed and operated.

Design and analysis of fixture for easy lug plate fit up at bend portion of first pass and second pass gang bend water wall panels phase I

With the technological evolution of “high-pressure steam generators” from sub-critical to the super-critical stage, the “Water-wall Panels” is transformed from “straight panels” to “terminal bend panels” and “gang bend panels”. The lug plates are fitted at the bend portion of the terminal and gang bend panels as per the design. The traditional method of lug plate fit up has an awkward impact on the working method, productivity, quality, and re-work. This paper aims to discuss the design and analysis of the fixture to avoid the manual lug plate fit up. With the proposed design of the fixture, the lug plate fit up can be done easily at the bend portion of tubes of gang bend and terminal bend “Water-wall Panels”. Proposed design not only solves the problems being faced while giving the easy fit up but also brings in marked improvements in workplace-safety, productivity, working environment coupled with a considerable reduction in manpower and operational risks.

Machine learning modeling and experimental study to forecast the pressure of Very High-Pressure (VHP) steam in an industrial steam cracking process

The steam cracking process converts hydrocarbons such as ethane and propane into ethylene, propylene and etc. In this study, a number of crucial features, which can affect the furnace output of Very High-Pressure steam (VHP), are studied. Thus, a set of experiments is conducted at a petrochemical plant to determine the effect of the coil’ outlet temperature of cracked hydrocarbon gas, the feed flow rate, dilution steam (DS), negative pressure in the furnace, and flow rate of injected water into steam on the pressure of VHP steam. In addition, the credibility of industrial data is confirmed using the Leverage method. It is found that a maximum VHP steam pressure for each feed flow rate is obtained when the ratio of dilution steam to the feed rate roughly equals 0.37. The mentioned ratio also controls the coke formation in the reactor coils. In the following, three effective machine learning methods are developed, based on 1077 industrial data samples covering a wide operating conditions' range, for estimating process' VHP steam pressure. The model built by radial basis function (RBF) shows sprier agreement with plant data with an average absolute relative deviation (AARD), standard deviation (SD), and R2 values of 0.11%, 0.79% and 99.33%, respectively, for total data points. It is revealed that the developed models are reliable for controlling the amount of VHP steam pressure by changing feed flow rates, the flow rate of injected water into steam, dilution steam, and the temperature of outlet cracked hydrocarbon gas. In addition, a sensitivity analysis is accomplished using Spearman's correlation coefficient based on the most accurate RBF model.

Frictionless Energy Generation using Flywheel

Electricity is one of the most significant gifts that science has bestowed upon humanity. It has also become an integral part of modern life such that it is difficult to imagine a world without it. Electricity has numerous applications in our daily lives. Energy is usually produced by non-renewable sources such as petrol, Kerosene and nuclear which unfortunately create pollution. These methods are inconvenient in many ways. Burning of non renewable sources are hazardous to environment as it produces harmful gases. The batteries which are used to produce electricity is also manufactured using harmful substaces. Using high pressure steam and batteries are expensive and hard to maintain. The intention of this project is to producing energy without creating pollution and use it to power light bulbs, cell phones, laptops, and other small appliances. This project is great help to develop our engineering skills while learning about a clean way of generating electricity and satisfying our basic requirement. We are going to use the hard drive,magnet and inductive coil to generate electricity due to which our mobile phone will be charge and followed by ac to dc converter. This is totally clean way of generating energy. As fuel is not a renewable energy source and the prices are increasing day by day. It will not be affordable by a common man after some period. Here no fuel is required to generate electricity, so everybody can afford this method for power generation also it eliminates the emission of CO2 which will reduces the pollution. Conventional methods for generating electricity make use of dynamo and wind turbine, but they have disadvantage that they produce friction and reduces speed which require more efforts For the project to work we need strong electromagnets so we have used Neodymium magnets and also used.

Design and Development of Robot for Industrial Pipe Cleaning and Inspection

Nowadays many industries used different diameter pipes for different applications like carrying chemicals, high-pressure steam, and gasses hence there may be chances of problems like corrosion, and leakages. The proposed system suggests the robot will be built to clean the residues that are built up inside the pipe. This is done through a brushing mechanism. Not only this robot will also be able to relay live video feedback from the ground to the controller that the user has. By this, the users can verify the cleaning that is done by the robot.

Ponašanje materijala X10CrMoVNb9-1 prilikom ponovljenog termičkog tretmana tokom montaže

The paper presents comparative test results of X10CrMoVNb9-1 steel collector samples. The influence of repeated heat treatment on the properties of the material was investigated, and the samples underwent a different number of thermal cycles. This material is most often used for pipes and pipe connections resistant to high pressures and temperatures. Steel is characterized by high thermal strength properties, which is why it is used in thermal power plants for superheater pipes, collectors as well as for high pressure steam pipes. It can be used even at high temperatures up to 600°C. The aim of this paper is the behaviour of the material during repeated heat treatment, which often occurs during the installation of the pipeline, and is caused by the repair of defects in the welded joint, incorrect installation of the pipeline and similar procedures.

Root cause of embrittlement of in-service exposed high pressure steam pipeline

A segment of tube cut off from the high pressure steam pipeline was subjected to routine basic material tests, which resulted in very low impact energy of the pipe material (low-alloyed Cr steel). A part of the segment (and a comparative non-operated sample) was then subjected to detailed mechanical tests (including creep), metallographic investigations and fractographic analyses with an aim to determine a root cause of the embrittlement. The results showed that grain boundaries of exposed steel are covered by particles of primary and secondary cementite. However, a matrix is weakened more, therefore a fracture of creep, tensile and impact specimens is always transgranular and the cleavage facets are limited to grain size, if present. Thus, the cause of embrittlement was determined not by a rapid ageing, but by an unsuitable initial heat treatment of the pipe material.

Energetics of formation and stability in high pressure steam of barium lanthanide cobaltite double perovskites.

This study concerns energetics of formation and the stability in high water partial pressure of BaLnCo2O6-δ, (Ln = La, Pr, Nd, and Gd) (BLnC) and BaGd1-xLaxCo2O6-δ, where x = 0.2, 0.5, and 0.7 (BGLC) double perovskite cobaltites. Those materials are extensively studied due to their potential applications as a positrode in electrochemical devices. Therefore, their stability under such conditions is a key issue. All investigated materials are thermodynamically stable relative to binary oxides and exhibit strongly exothermic enthalpies of formation. Moreover, BaGd0.3La0.7Co2O6-δ and BaGd0.8La0.2Co2O6-δ remain the main perovskite structure up to 3 bars of water vapor at 400 °C. At higher steam pressure, reaching 10 bar at 300 °C, the partial decomposition to constituent oxides and hydroxides was observed. The BGLC compounds exhibit higher negative formation enthalpies in comparison to single-Ln compositions, which does not translate into higher chemical stability under high steam pressures since the BLnC series retained the main perovskite structure at higher temperatures as well as in higher water vapor pressures.

Exploring the viability of fly ash bricks as an alternative material for building construction

Fly ash, which is recovered from the gases produced when coal is burned to produce power, is essentially a fine glass powder. Fly ash is a siliceous substance that has an amorphous or glassy bulk associated with it. These tiny earth elements are mainly composed of silica, alumina, and iron. When flyash is combined with lime and water, a cementitious substance is created. Under conditions of high steam pressure and temperature, the components of flyash combine with lime to form calcium silicate-hydrate and calcium aluminate hydrate. Portland cement and this newly produced solvent have characteristics that are very comparable. Due to their similarity, fly ash and cement can be substituted as a fundamental element in concrete, with fly ash having certain clear quality advantages. The surfaces produced by this concrete's formation are smoother, tighter, and denser, improving the characteristics of fly ash. In developing countries, flyash bricks are an economical and efficient means of low and medium-rise building construction, using very less resources. This paper examines the case of Flyash bricks for load-bearing wall construction as well as filler material and also discusses the engineering viability and properties of such Flyash bricks. The paper comes to the conclusion that Flyash bricks are a practical substitute for traditional bricks with more ancillary advantages.

Evaluation of mechanical and antibacterial properties of Cu-DLC composite films

Diamond-like carbon (DLC) films had been formed as a surface treatment for intracorporal device for decreasing the coefficient of friction. DLC film showed significant stability without being damaged during acid immersion and high-pressure steam sterilization. However, bacteria that adhere to medical devices lead to the induction of infectious diseases associated with therapeutic actions. Therefore, maintenance of a hygienic surface condition has been strictly required. This study demonstrated the fabrication of DLC films (gas source: CH4), which incorporated Cu (Cu-DLC). The Cu-DLC films were synthesized on a Si (100) substrate via plasma-enhanced chemical vapor deposition and magnetron sputtering. The surface morphology, microstructure, element contents, wear resistance, hardness, and antibacterial properties of the films were experimentally analyzed. Cu particles were considered not uniformly distributed in the DLC film, they embedded in DLC films formed a three-dimensional structure led to higher roughness. The Cu-DLC exhibited wear resistance and higher hardness compared to Cu. After inoculation, Cu-DLC films showed higher antibacterial activity against E. coli than pure DLC. It is expected that the hygienic films with excellent mechanical properties demonstrated in the present study will be utilized in various medical and industrial sectors.

Structural and thermal analysis on high-pressure steam turbine blade to determine the optimum material for its manufacturing

Blades of turbines are key elements of steam turbines. They are the main energy driven components at every stage of steam turbine where steam is pressurized to generate power. In view of designing, the material used and dimensions of blade govern the efficiency, consistency and durability of a steam turbine. In this paper the design of aerofoil profile of HP steam turbine blade is modelled by using computer-aided three-dimensional interactive application (CATIA). Various analytical data viz.., static structural analysis, transient structural analysis and transient thermal analysis are performed on different materials (ATI 720, Waspaloy, Molybdenum TZM, Incoloy alloy, Inconel alloy 725). Based on the analysis, Waspaloy material blade outperformed among all blades materials in terms of creep resistance and heat flux.