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Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 405
Author(s):  
Artur Kudyba ◽  
Jafar Safarian

The recovery of Mn and Al from two industrial waste of ferromanganese and aluminum production processes was investigated via implementing a high temperature smelting—aluminothermic reduction process. The experiments were carried out with or without CaO flux addition, and two dross qualities. It was observed that the prepared mixtures of the materials yield homogeneous metal and slag products in terms of chemical composition and the distribution of phases. However, the separation of produced metal phase from the slag at elevated temperatures occurs when a higher amount of CaO is added. Viscosity calculations and equilibrium study indicated that the better metal and slag separation is obtained when the produced slag has lower viscosity and lower liquidus. It was found that the process yields Al-Mn-Si alloys, and it is accompanied with complete recovery of Mn, Si and Fe and the unreacted Al in the process. Moreover, the quality of metal product was less dependent on the slightly different dross quality, and the concentration of minor Ca in metal is slightly increased with significant increase of CaO in the slag phase.


Processes ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 91
Author(s):  
Oke Oktavianty ◽  
Shigeyuki Haruyama ◽  
Yoshie Ishii

The multi-drop method with a good droplet quality is a big challenge in inkjet technology. In this study, optimization of Drop on Demand (DoD) inkjet printer waveform design was conducted. The effectiveness of the waveform design, so-called W waveform, from previous study as a preliminary vibration for the multi-drop ejection method was investigated. The unmodified W waveform was proven not to be an effective waveform for lower viscosity of liquid, especially when compared by the standard waveform obtained from a print-head manufacturer. Edible ink with a viscosity below the optimum range for print-head specifications was employed as the operating liquid. The preliminary vibration W waveform was modified to improve the droplet quality of the edible ink. It was proven that a 40% adjusted voltage of the rear wave of the W waveform was effective as the optimum waveform design for edible ink. The droplet quality of the multi-drop ejection method for grey-scale technology was improved by optimizing the W waveform design.


2021 ◽  

To achieve higher brake thermal efficiency (BTE) and improve vehicle economy, the new development of dedicated hybrid engine (DHE), adopting the Atkinson or Miller cycle, has been becoming the current development trends. A base 1.5L natural aspiration (NA) engine with deep Atkinson cycle has been developed for dedicated hybrid vehicle application, which can achieve the highest BTE of 41.19%. In order to achieve higher BTE, several potential technologies which are easy for mass production application have been studied progressively, such as, higher compression ratio (CR), optimized exhaust gas recirculation (EGR) pick point, lower EGR temperature, higher EGR rate, higher RON number fuels, heat transfer reduction by polishing valve head, light boost, lower viscosity oil. The results show the combined technology application can achieve the highest engine BTE of 42.59%. This paper provides the studied technical routine and the achieved benefits step by step.


2021 ◽  
Author(s):  
Ibrahim Al-Hulail ◽  
Oscar Arauji ◽  
Ali AlZaki ◽  
Mohamed Zeghouani

Abstract Proppant placement in a tight formation is extremely challenging. Therefore, using a high viscous friction reducer (HVFR) as a fracturing fluid for stimulation treatment in tight gas reservoirs is increasing within the industry because it can transport proppant, help reduce pipe friction generated during hydraulic-fracturing treatments, and efficiently clean up similar to the lower viscosity friction reducers (FRs). In this paper the implementation of the robust HVFR that is building higher viscosity at low concentrations, which minimizes energy loss and promotes turbulent flow within the pipe during the pumping of low viscosity, is discussed in detail. Performance evaluation of the new HVFR was conducted in the laboratory and compared to the lower viscosity FR. The study consisted of viscosity measurements at 70 and 180°F, compatibility with other additives, and proppant transport capabilities. Additionally, the viscosity generated from both FRs was compared using two water sources: water well A and treated sewage water. Viscosity measurements were performed across a wide range of FR and HVFR concentrations and under varying shear rates using a digital viscometer. To validate drag reduction capabilities for this HVFR in the field, the same groundwater with low salinity and low total dissolved solids (TDS) content were used for comparison purposes. The test plan for this new HVFR was for a well to be drilled to a total depth of 17,801 ft MD (10,693 ft TVD) with a 6,016-ft lateral section. Another part of the plan was to complete 41 stages—the first stage with the toe initiator, and subsequent stages using ball drops until Stage 8, were completed using the current FR. For Stage 8, the drag reduction from the new HVFR was evaluated against the current FR only during the pad stage. Then, FR or HVFR concentrations were used, with a gradual reduction from 2 to 1 gpt without compromising proppant placement from stages 9 to 37, alternating current FR and the new HVFR every four stages. From Stage 38 to 41, the same approach was used but with treated sewage water and alternating every other stage using current FR or HVFR at 1gpt. The implementation of the new HVFR showed better friction reduction when using the same concentration of the current FR. Also, achieving better average treating pressures with lower concentration. Based on that it is a cost-effective solution and the performance is better, this lead to reduce the HVFR volume to be pumped per stage compared to the current FR. Applications/Significance/Novelty For this study, drag reduction capabilities for this new HVFR were validated in the field at higher pumping rate conditions, potentially optimizing (reducing) the polymer concentration during a freshwater application. It was shown that lower concentrations of this HVFR provided higher viscosity, which helps improve proppant transport and operation placement.


Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7724
Author(s):  
Agnieszka Adamczuk ◽  
Milena Kercheva ◽  
Mariana Hristova ◽  
Grzegorz Jozefaciuk

Chitosan has become increasingly applied in agriculture worldwide, thus entering the soil environment. We hypothesized that chitosan should affect the water stability of soil. Since this problem has not been studied to date, we examined, for the first time, the influence of chitosan on the water stability and wettability of soil aggregates. The aggregates were prepared from four soils with various properties amended with different amounts of two kinds of powdered chitosan, and subjected to 1 and/or 10 wetting–drying cycles. The water stability was measured by monitoring air bubbling after aggregate immersion in water, and the wettability was measured by a water drop penetration test. The biopolymer with a lower molecular mass, lower viscosity, and higher degree of deacetylation was more effective in increasing the water stability of the soil than the biopolymer with a higher molecular mass, higher viscosity, and lower deacetylation degree. After a single wetting-drying cycle, the water stability of the soil aggregates containing chitosan with a higher molecular mass was generally lower than that of the soil; after ten wetting–drying cycles, the water stability increased 1.5 to 20 times depending on the soil. The addition of low-molecular-mass chitosan after a single wetting-drying cycle caused the water stability to become one to two hundred times higher than that of the soil. A trial to find out which soil properties (pH, C and N content, bulk density, porosity, and particle size distribution) are responsible for the effectiveness of chitosan action was not successful, and this will be the objective of further studies.


Author(s):  
Zakiyeh Yousefian ◽  
Martin Trulsson

Abstract We study the rheological response of dense suspensions of elliptical particles, with an aspect ratio equal to 3, under oscillatory shear flows and imposed pressure by numerical simulations. Like for the isotropic particles, we find that the oscillatory shear flows respect the Cox-Merz rule at large oscillatory strains but differ at low strains, with a lower viscosity than the steady shear and higher shear jamming packing fractions. However, unlike the isotropic cases (i.e., discs and spheres), frictionless ellipses get dynamically arrested in their initial orientational configuration at small oscillatory strains. We illustrate this by starting at two different configurations with different nematic order parameters and the average orientation of the particles. Surprisingly, the overall orientation in the frictionless case is uncoupled to the rheological response close to jamming, and the rheology is only controlled by the average number of contacts and the oscillatory strain. Having larger oscillatory strains or adding friction does, however, help the system escape these orientational arrested states, which are evolving to a disordered state independent of the initial configuration at low strains and ordered ones at large strains.


2021 ◽  
Vol 11 (23) ◽  
pp. 11205
Author(s):  
Cong Yuan ◽  
Lisha Zhu ◽  
Shiqi Liu ◽  
He Li

The higher susceptibility to cavitation in poppet valves due to the lower viscosity of water than the traditionally used mineral oil poses a challenge in fluid transmission technology. To reveal the underlying mechanism of cavitating flow physics associated with the variation in viscosity effect, the current paper examines both the water and oil cavitating flow dynamics inside poppet valves with varied structures through a numerical study. The simulation results are validated with a comparison to previous experimental data in terms of cavitation morphology and pressure distribution. According to the predicted cavitation distribution, three kinds of cavitation occurred at separated positions in both water- and oil-flow cases. The vortex cavitation, which in the oil-flow case displays a remarkable paired structure with favorable coherence, is featured with a scattered dispersion in the water-flow case, while the profound attached cavitation at the poppet trailing edge in the water-flow case almost disappears in the oil-flow case. Furthermore, the attached cavitation within the chamfered groove has higher stability in the oil-flow case, compared to the thorough detachment behavior featured with profound 3-dimensionality in the water-flow case. According to the potential core and vortex evolution, the strong 3-dimensionality due to the violent laminar-turbulent transition in the water-flow case together with the produced puff pattern of the potential core, to a large extent, interrupts the periodic behavior of cavitation, which is essentially preserved in the oil-flow case featured with favorable coherence.


Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 4005
Author(s):  
Chia-Wei Chang ◽  
Jyun-Ya Liao ◽  
Kun-Tsung Lu

The manufacture and properties of waterborne UV-cured coatings (WUV coatings) by acetone process based on urushiol for wood finishing were investigated. Firstly, epoxide urushiol (EU) was prepared by reacting urushiol with epichlorohydrin. Secondly, the EU was reacted with acrylic acid to obtain acrylic epoxide urushiol (AEU). Next, the prepolymers were synthesized by the reaction of AEU, 2,2-Bis(hydroxymethyl)propionic acid (DMPA), and isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI), respectively, using acetone as a solvent. The prepolymers were further neutralized by triethylamine (TEA) to obtain ionomers and dispersed in the water. After removing the acetone by vacuum distillation, the polyurethane dispersions (PUDs) were obtained. Finally, the WUV coatings were performed by adding a photoinitiator (Irgacure 2959). The products in the synthesized processes and the properties of the WUV coatings were examined. The results showed that the EU, AEU, prepolymers, and ionomers could be synthesized stably. The PUDs synthesized by the IPDI and HDI had a similar solid content of 25.2% and 26.2%, and similar pH values of 7.8 and 7.6. However, the IPDI-containing PUD displayed lower viscosity, smaller particle size, and a more even polydispersity index. The IPDI-containing WUV film displayed a higher hardness, gloss, and lightfastness. The HDI-containing WUV film possessed superior impact resistance. Both IPDI-containing and HDI-containing WUV films showed excellent adhesion, bending resistance, and mass retention, and demonstrated a potential for wood finishing.


2021 ◽  
Vol 22 (22) ◽  
pp. 12207
Author(s):  
Joanna Niesiobędzka ◽  
Ewa Głowińska ◽  
Janusz Datta

This study concerns bio-based urethane prepolymers. The relationship between the chemical structure and the thermal and processing parameters of bio-based isocyanate-terminated ether and ester-urethane prepolymers was investigated. Bio-based prepolymers were obtained with the use of bio-monomers such as bio-based diisocyanate, bio-based polyether polyol or polyester polyols. In addition to their composition, the bio-based prepolymers were different in the content of iso-cyanate groups content (ca. 6 and 8%). The process of pre-polymerization and the obtained bio-based prepolymers were analyzed by determining the content of unreacted NCO groups, Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, thermogravimetry, and rheological measurements. The research conducted facilitated the evaluation of the properties and processability of urethane prepolymers based on natural components. The results indicate that a significant impact on the processability has the origin the polyol ingredient as well as the NCO content. The thermal stability of all of the prepolymers is similar. A prepolymer based on a poly-ether polyol is characterized by a lower viscosity at a lower temperature than the prepolymer based on a polyester polyol. The viscosity value depends on the NCO content.


2021 ◽  
Author(s):  
Alexander Sergeevich Koplik ◽  
Semen Sergeevich Kudrya ◽  
Denis Alekseevich Zolnikov ◽  
Rustam Albertovich Koltsov ◽  
Alexey Vasilievich Kovalevskiy

Abstract Executive Summary The recently developed Samotlor 2020 campaign includes a requirement to shift the Frac design to synthetic gelling agent (gellant) which would increase production, keep the reservoir clean and also reduce both capital and operational costs for each stage Frac stage (no need to heat up the water, an option to use the well water, no requirement to miniFrac performance, etc.). The key difference between guar-based gels and synthetic gels is a lower viscosity rating that results in a significant increase in the fracture length and an improved ability to transport high concentration of proppant due to its thixotropic properties (the ability of a substance to lower its viscosity as a result of a mechanical impact and grow its viscosity when still). When gel is destroyed throughout the fracture after the Frac is completed the synthetic option allows for a cleaner fracture and helps remove all residual matter from the fracture. Another important consideration is that guar shipments from India make Russian oil vulnerable to price, foreign exchange and availability fluctuations. If guar crops experience a bad year or Indian farmers determine that the market should be refocused on cotton or other areas (i.e. not guar), the guar prices in Russian would likely skyrocket. The authors worked as a team to come up with a list of clear recommendations to develop both new and existing wells for Lower Cretaceous collectors of the Vartovsk and Megion suites such as AV1 (1-2) and BV8(0) to increase production and reduce capital costs. We have determined that Frac fluids based on synthetic modified polyacrylamide start to come to the front and hold a leading position in the area of production stimulation as previously happened to other effective methods such as polymer water flooding, drilling and cementing applications.


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