scholarly journals Chemical Selection for Flocculation of the Sludges Produced During Lime Neutralization of Acidic Spent Pickling Solutions and Rinse Water from Steel Pipe Mill

2020 ◽  
Author(s):  
Nikolay Tsarev ◽  
Elena Tatyannikova
Keyword(s):  
Response Surfaces ◽  
Steel Pipe ◽  
Chromatographic Paper ◽  
Capillary Suction ◽  
Acid Pickling ◽  
Steel Mills ◽  
Rinse Water ◽  
The Impact ◽  
Pipe Mill ◽  
Wastewater Sludges

Acidic spent pickling solutions and rinse water are produced during steel pipe acid pickling. They are usually neutralised with lime in a neutralisation plant and pumped in the form of a wet sludge to a landfill. This is one of the main environmental issues of Russian steel mills. The implementation of sludge treatment units, including equipment for sludge polymer conditioning and dewatering, is an import consideration when seeking to reduce the impact of steel mills on human health and the environment. The researches results of polymer conditioning of the aggressive wastewater sludges by flocculants are reflected in the paper. Sludge samples were obtained from the neutralisation plant of an Ural’s steel pipe mill. Sludges of two types were investigated: the sludge which is formed in clarifiers during spent pickling solutions neutralization with lime and the sludge which is formed in clarifiers during rinse water neutralization with lime. During the work non-ionic, cationic, and anion flocculants Praestol® efficiency was estimated. The shortest time of water capillary suction from the flocculated sludge was accepted as efficiency criterion of flocculant processing. It was defined with use of the capillary suction timer Fann® and Whatman® 17 chromatographic paper. It is established that: non-ionic focculant Praestol® 2500 dose of 4–5 g/kg dry solids is effective for conditioning of the sludge produced during lime neutralization of acid spent pickling solutions; the anionic flocculant Praestol® 2540 dose of 1.5–2 g/kg dry solids is effective for conditioning of the sludge produced during lime neutralization of acid rinse water. The empirical response surfaces and the contour plots showing the relationship between capillary suction time and a dosage of flocculant and a charge density (% hydrolysis) of a flocculant were reveived. Keywords: steel pipe mill, acid pickling, wastewater, sludges, flocculants, capillary suction time

Optimization of Trenched Film Cooling Using RSM Coupled CFD

2018 ◽  
Vol 0 (0) ◽  
Author(s):  
V.G. Krishna Anand ◽  
K.M. Parammasivam
Keyword(s):  
Film Cooling ◽  
Three Dimensional ◽  
Response Surfaces ◽  
Test Surface ◽  
Response Factor ◽  
Film Cooling Effectiveness ◽  
Blowing Ratio ◽  
Flow Parameters ◽  
Considerable Impact ◽  
The Impact

AbstractThe trench film cooling employs film holes embedded in a slot created on the surface that requires protection from the impact of hot mainstream flow. The present investigation employs Response Surface Methodology (RSM) approach coupled with CFD analysis to develop a regression predictive model and to optimize the trench geometric and flow parameters viz., trench width (w), trench depth (d), film hole compound angle (β) and blowing ratio (M). The Area-averaged film cooling effectiveness (ȠAA) were chosen as a response factor for RSM and with trench design and flow parameters used as input factors for regression analysis. Analysis of variance (ANOVA) analysis was carried out on the regression model to identify the influence of individual parameters. Three dimensional response surfaces that relate the effect of input parameters on the response factor were analyzed. Experimental results of a case identified from the RSM matrix was found to correlate well with computational investigations. Results from the study indicate that the parameters d, β and M have considerable impact on film cooling performance of test surface with trenches.

scholarly journals Impact Resistance Analysis and Optimization of Variant Truss Beam Structure Based on Material Properties

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5847
Author(s):  
Xiaohao Li ◽  
Junqi Pan ◽  
Xingchen Zhou
Keyword(s):  
Simulation Analysis ◽  
Impact Load ◽  
Impact Resistance ◽  
Structure Design ◽  
Response Surfaces ◽  
Optimization Strategy ◽  
Buffer Effect ◽  
Characteristic Analysis ◽  
Beam Structure ◽  
The Impact

In order to meet the increasing application requirements with regards to structural impact resistance in industries such as mining, construction, aerospace engineering, and disaster relief and mitigation, this paper designs a variant truss beam structure with a large shrinkage ratio and high impact resistance. Based on the principle of the curved trajectory of scissor mechanisms, this paper conducts a finite element simulation analysis of the impact load on the truss beam structure, a theoretical analysis of the impact response and a relevant prototype bench-top experiment, completing a full study on the impact resistance mechanism of the designed variant truss beam structure under the impact load. In the paper, the buffer effect of the external load impact on the variant truss beam structure is analyzed from the perspective of the energy change of elastic–plastic deformation. This paper proposes an optimization strategy for the variant truss beam structure with the energy absorption rate as the optimization index through extensive analysis of the parameter response surfaces. The strategy integrates analyses on the response characteristic analysis of various configuration materials to obtain an optimal combination of component parameters that ensures that the strength of the truss beam structure meets set requirements. The strategy provides a feasible method with which to verify the effectiveness and impact resistance of a variant truss structure design.

Research of the Stainless Steel-Concrete-Carbon Steel Circular Concrete-Filled Double Skin Steel Tubes under Axial Compression

2014 ◽  
Vol 1065-1069 ◽  
pp. 1349-1353
Author(s):  
Zhen Kai Duan ◽  
Rui Wang
Keyword(s):  
Stainless Steel ◽  
Carbon Steel ◽  
Fire Resistance ◽  
Steel Tube ◽  
Steel Pipe ◽  
Building Structures ◽  
Light Pressure ◽  
Structure Variation ◽  
Concrete Filled Steel Tube ◽  
The Impact

Concrete-Filled Steel Tube with high capacity, good ductility and toughness, convenient construction, good fire resistance and other advantages. Currently[1] . Concrete-Filled Steel Tube structure has been widely used in the basic components and the overall structure of behavioral research has made many achievements. There are many advantages of concrete pipe above, but it also has fatal flaws, Stainless steel steel that is the difference[2]. The stainless steel has a beautiful appearance, durability, corrosion resistance, low maintenance costs, good fire resistance and other advantages. New stainless steel pipe concrete structure has both ordinary steel concrete good mechanical properties and excellent durability of stainless steel, can be widely used in buildings and bridges of the marine environment as well as some of the high durability and aesthetic requirements important building structures. Based on the outer stainless steel hollow sandwich - the carbon steel pipe shaft of light pressure test concrete results of load and displacement of the structure, variation of load and strain, and the impact of the empty heart of these parameters.

The impact of clean-in-place parameters on rinse water effectiveness and efficiency

2018 ◽  
Vol 222 ◽  
pp. 276-283 ◽  
Author(s):  
Mengyuan Fan ◽  
David M. Phinney ◽  
Dennis R. Heldman
Keyword(s):  
Effectiveness And Efficiency ◽  
Rinse Water ◽  
The Impact

Climate change impact evaluation in various regions in Europe on the base of ensemble modelling

2020 ◽  
Author(s):  
Jaromir Krzyszczak ◽  
Piotr Baranowski ◽  
Monika Zubik
Keyword(s):  
Climate Change ◽  
Response Surfaces ◽  
Mitigation Strategies ◽  
Climate Conditions ◽  
Crop Models ◽  
Climate Change Uncertainty ◽  
Arable Fields ◽  
Four Levels ◽  
The Impact ◽  
Adaptation Options

<p>Climate change uncertainty largely complicates adaptation and risk management evaluation at the regional level, therefore new approaches for managing this uncertainty are still being developed. In this study three crop models (DNDC, WOFOST and DSSAT) were used to explore the utility of impact response surfaces (IRS) and adaptation response surfaces (ARS) methodologies (Pirttioja et al., 2015; Ruiz-Ramos et al., 2018).</p><p>To build IRS, the sensitivity of modelled yield to systematic increments of changes in temperature (-1 to +6°C) and precipitation (-30 to +50%) was tested by modifying values of baseline (1981 to 2010) daily weather. Four levels of CO2 (360, 447, 522 and 601 ppm) representing future conditions until 2070 were considered. In turn, to build ARS, adaptation options were: shortening or extending the crop cycle of the standard cultivar, sowing earlier or later than the standard date and additional irrigation. Preliminary data indicate that yields are declining with higher temperatures and decreased precipitation. Yield is more sensitive to changes in baseline temperature values and much less sensitive to changes in baseline precipitation values for arable fields in Finland, while for arable fields in Germany, ARS indicates yield sensitivity at a similar level for both variables. Also, our data suggests that some adaptation options provides increase of the yield up to 1500 kg/ha, which suggest that ARSs may be valuable tool for planning an effective adaptation treatments. This research shows how to analyze and assess the impact of adaptation strategies in the context of the high level of regional uncertainty in relation to future climate conditions. Developed methodology can be applied to other climatic zones to help in planning adaptation and mitigation strategies.</p><p>This study has been partly financed from the funds of the Polish National Centre for Research and Development in frame of the project: MSINiN, contract number: BIOSTRATEG3/343547/8/NCBR/2017</p>

Evaluation of Residual Stresses Induced by Repairs to Small Diameter Stainless Steel Pipe Welds

2015 ◽  
Author(s):  
Trevor G. Hicks ◽  
William R. Mabe ◽  
Jason R. Miller ◽  
John V. Mullen
Keyword(s):  
Stainless Steel ◽  
Residual Stresses ◽  
Large Diameter ◽  
Small Diameter ◽  
Steel Pipe ◽  
Limited Information ◽  
Diameter Pipe ◽  
Stainless Steel Pipe ◽  
Lower Magnitude ◽  
The Impact

Residual stresses within stainless steel pipe welds may cause or exacerbate in-service cracking. Significant investigative efforts have been devoted to the examination of piping residual stresses in large diameter piping using both finite element modeling and experimental techniques, but limited information is available for small diameter piping. Even less information is available for small diameter piping welds which have been repaired or re-worked during initial fabrication. This investigation used both experimental methods and analytical modeling to assess the impact of repair welding during initial fabrication on the residual stresses along the inner diameter (ID) of small diameter pipe specimens. The investigation showed that tensile axial residual stresses were located in the heat affected zone (HAZ) along the ID of the pipe specimens adjacent to regions which were excavated and re-welded. Such repair welds were also shown to markedly increase the magnitude of the tensile axial residual stresses for weld configurations which otherwise had lower magnitude residual stresses.

scholarly journals Impact strength of Friction Stir Welded joints of dissimilar Aluminum alloy

2020 ◽  
Vol 9 (4) ◽  
pp. 2491-2496
Keyword(s):  
Aluminum Alloy ◽  
Impact Toughness ◽  
Impact Strength ◽  
Welded Joints ◽  
Response Surfaces ◽  
Design Matrix ◽  
Friction Stir ◽  
Contour Plots ◽  
Fsw Parameters ◽  
The Impact

Joining processes has been the heart of the manufacturing processes. Welding has played an important part in joining processes since its inception. Friction Stir Welding (FSW) has given promising results especially in the case of aluminum alloys. In the present paper, dissimilar aluminum alloy heat-treatable AA6082 T651and non-heat treatable AA 5083 O were friction stir welded as per design matrix generated according to the rotatable central composite design of response surface methodology. Impact toughness was measured from samples of welded joints. The impact toughness was mapped in terms of FSW parameters and the regression equation is generated. The response surfaces and contour plots are drawn and interpreted. The input parameters are optimized to achieve maximum impact strength. Confirmation runs were performed and found results were found close to the optimized values. The present research is useful for further augmentation of the FSW process of aluminum alloy.

Influence of the Cellulose and Soft Wood Fibres on the Impact and Tensile Properties in Polypropylene Bio Composites

2021 ◽  
Vol 903 ◽  
pp. 134-139
Author(s):  
Jānis Zicans ◽  
Remo Merijs Meri ◽  
Tatjana Ivanova ◽  
Andrejs Kovalovs ◽  
Piotr Franciszczak
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Impact Resistance ◽  
Tensile Modulus ◽  
Response Surfaces ◽  
Design Parameters ◽  
Cellulose Fibres ◽  
Highest Weight ◽  
Weight Content ◽  
The Impact

Investigation presents an experimental study of mechanical properties of hybrid bio-composites made from man-made cellulose fibres and soft wood microfiller embedded into polypropylene homopolymer matrix at different weight contents. Mechanical properties such as elastic modulus, tensile strength, and impact resistance of the reinforced composites determined for various total weight contents of both biobased fillers were used as the design parameters. The problem was solved by planning the experiments and response surfaces method. The results demonstrate that using the both filler types enhance the mechanical properties. The tensile modulus increases by ~115%. The bio-composite with the highest weight content of man-made cellulose fibres and the lowest content of soft wood microfibers possesses maximum tensile strength (more 66 MPa). Addition of man-made cellulose fibres demonstrate a significant influence on the impact resistance of the investigated composites.

scholarly journals Baseline Evaluation of the Impact of Updates to the MIT Earth System Model on its Model Parameter Estimates

2018 ◽  
Author(s):  
Alex G. Libardoni ◽  
Chris E. Forest ◽  
Andrei P. Sokolov ◽  
Erwan Monier
Keyword(s):  
Land Surface ◽  
Probability Distributions ◽  
Land Surface Model ◽  
Response Surfaces ◽  
Surface Model ◽  
Model Parameters ◽  
Ocean Heat Uptake ◽  
Aerosol Forcing ◽  
Baseline Evaluation ◽  
The Impact

Abstract. For over twenty years, the Massachusetts Institute of Technology Earth System Model (MESM) has been used extensively for climate change research. The model is under continuous development with components being added or updated. To provide transparency in the model development, we perform a baseline evaluation of the newest version by comparing model behavior and properties to the previous model version. In particular, the impacts resulting from updates to the land surface model component and the input forcings used in historical simulations of climate change are investigated. We run an 1800-member ensemble of MESM historical climate simulations where the model parameters that set climate sensitivity, ocean heat uptake, and the net anthropogenic aerosol forcing are systematically varied. By comparing model output to observed patterns of surface temperature changes, the linear trend in the increase in ocean heat content, and upper-air temperature changes, we derive probability distributions for the three model parameters. Furthermore, we run a 372-member ensemble of transient climate simulations where model forcings are held fixed, absent an increase in carbon dioxide concentrations at the rate of 1 % per year. From these runs, we derive a response surface for transient climate response and thermosteric sea level rise as a function of climate sensitivity and ocean heat uptake. We compare the probability distributions and response surfaces derived using the current version of MESM to the preceding version to evaluate the impact of the updated land surface model and forcing suite. We show that the probability distributions shift towards higher climate sensitivities and weaker aerosol forcing in response to the new forcing suite. The climate response surfaces are relatively unchanged between model versions, indicating that the updated land surface model has limited impact on temperature evolution in the model.

Optimization of Protection Condition for Composite Freeze-Dried Starter of Paocai

2013 ◽  
Vol 798-799 ◽  
pp. 1087-1090
Author(s):  
Li Li ◽  
Xu Yan Zong ◽  
Li Xiong ◽  
Jing Zhang ◽  
Kai Chen
Keyword(s):  
Mathematical Model ◽  
Stepwise Regression ◽  
Orthogonal Design ◽  
Skim Milk ◽  
Response Surfaces ◽  
Quadratic Polynomial ◽  
Sodium Glutamate ◽  
Freeze Dried ◽  
The Impact ◽  
The Mathematical Model

To obtain the better formula of the biomaterials lyoprotectant for composite starter of Paocai, five lyoprotectants were studied with math method those are orthogonal design, Quadratic polynomial stepwise regression and etc. The results showed, 14.7% of hydrolyzate of skim milk, 1.1% of amount of glucose, 3.4% of amount of glycerol, 5.0% of amount of sodium glutamate, 1.2% of amount of Vc were added to the culture of Lactobacillus. After lyophilized, colonies of freeze-dried starters can reach 3.25×1010 cfu/mL. Response surfaces are drawn according to the mathematical model among factors, and it was discussed the impact of lyoprotectants.

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