scholarly journals Effects of Operational Parameters on the Low Contaminant Jarosite Precipitation Process-an Industrial Scale Study

Materials ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 4662
Author(s):  
Ali Asimi ◽  
Khodakaram Gharibi ◽  
Emad Abkhoshk ◽  
Farhad Moosakazemi ◽  
Saeed Chehreh Chelgani
Keyword(s):  
Extraction Process ◽  
Iron Removal ◽  
Industrial Scale ◽  
Precipitation Process ◽  
Operational Parameters ◽  
Neutralizing Agent ◽  
Leaching Experiments ◽  
Dissolution Efficiency ◽  
The Relationship ◽  
Zinc Dissolution

Jarosite precipitation process (JPP) is the most frequently used procedure for iron removal in the hydrometallurgical zinc extraction process. However, there is a gap in the knowledge of the relationship between operational parameters and the low contaminant JPP on the industrial scale. This study will address these issues by investigating the behavior of zinc calcine (ZC) as a neutralizing agent, exploring the source of zinc and iron through leaching experiments, and simulating the Jarosite process of the Bafgh Zinc Smelting Company (BZSC). The results showed that the zinc dissolution efficiency was 90.3% at 90 °C, and 73% of the iron present in the calcine can be solubilized. The main outcome was the iron removal of about 85% by alkaline ions present in ZC without the addition of any precipitating agent. The second target was to evaluate the effect of operational parameters on jarosite precipitation. Results revealed that increasing the temperature to 90 °C and the stirring rate to 500 RPM as well as adjusting the ZC’s pH during the jarosite precipitation remarkably improved iron removal. Considering all these factors in the plant could improve Fe precipitation to around 80% on average.

Biorefinery implementation for recovery debottlenecking at existing pulp mills- Part II: Techno-economic evaluation

TAPPI Journal ◽  
2012 ◽  
Vol 11 (8) ◽  
pp. 17-24 ◽  
Author(s):  
HAKIM GHEZZAZ ◽  
LUC PELLETIER ◽  
PAUL R. STUART
Keyword(s):  
Cost Estimation ◽  
Process Model ◽  
Black Liquor ◽  
Pulp Mill ◽  
Value Added ◽  
Economic Assessment ◽  
Extraction Process ◽  
Estimation Methods ◽  
Precipitation Process

The evaluation and process risk assessment of (a) lignin precipitation from black liquor, and (b) the near-neutral hemicellulose pre-extraction for recovery boiler debottlenecking in an existing pulp mill is presented in Part I of this paper, which was published in the July 2012 issue of TAPPI Journal. In Part II, the economic assessment of the two biorefinery process options is presented and interpreted. A mill process model was developed using WinGEMS software and used for calculating the mass and energy balances. Investment costs, operating costs, and profitability of the two biorefinery options have been calculated using standard cost estimation methods. The results show that the two biorefinery options are profitable for the case study mill and effective at process debottlenecking. The after-tax internal rate of return (IRR) of the lignin precipitation process option was estimated to be 95%, while that of the hemicellulose pre-extraction process option was 28%. Sensitivity analysis showed that the after tax-IRR of the lignin precipitation process remains higher than that of the hemicellulose pre-extraction process option, for all changes in the selected sensitivity parameters. If we consider the after-tax IRR, as well as capital cost, as selection criteria, the results show that for the case study mill, the lignin precipitation process is more promising than the near-neutral hemicellulose pre-extraction process. However, the comparison between the two biorefinery options should include long-term evaluation criteria. The potential of high value-added products that could be produced from lignin in the case of the lignin precipitation process, or from ethanol and acetic acid in the case of the hemicellulose pre-extraction process, should also be considered in the selection of the most promising process option.

APPLICATION OF EXTRACTION METHOD FOR ISOLATION OF BIOGENIC SURFACE-ACTIVE RHAMNOLIPIDS

2020 ◽  
Vol 2020 (60) ◽  
pp. 7-13
Author(s):  
Іlоna KARPENKO ◽  
◽  
Galyna MIDYANA ◽  
Olena KARPENKO ◽  
Igor SEMENIUK ◽  
...  
Keyword(s):  
Lone Pair ◽  
Physicochemical Characteristics ◽  
Extraction Process ◽  
Pseudomonas Sp ◽  
Free Energies ◽  
Isolation And Purification ◽  
Priority Task ◽  
Surface Active ◽  
Modern Biotechnology ◽  
The Relationship

The priority task of modern biotechnology is development of the rational technologies for the microbial synthesis of practically important products. Among these products, a significant place belongs to surfactants (biosurfactants), which are widely used in many sectors of the economy. The most problematic stage of the biosurfactants production is isolation from the post fermentative cultural liquid of bacteria-producers. Improving the efficiency of the biosurfactants production is highly dependent on rational approaches to the target products isolation. In this regard, there is an increasing need for rational, scientifically substantiated methods for their isolation and purification. Therefore, the aim of the presented work was to determine the optimal extractants for the isolation of rhamnolipid surfactants – metabolites of bacteria of Pseudomonas sp. PS-17 strain. For this purpose, the extraction process of rhamnolipids from the post fermentative cultural liquid supernatant has been investigated. The optimal extractants were selected among 13 organic solvents of different nature. Processing of the obtained experimental data by the method of multi-parameter equations of linearity of free energies (modified Koppel-Palm equation) made it possible to establish the relationship between the physicochemical properties of the extractants and amounts of the biosurfactants which were isolated from cultural liquid supernatant. It was shown that the data on the rhamnolipids extraction are adequately associated with the physicochemical characteristics of the solvents using a six-parameter linear equation. It was determined that the polarizability and molar volume are the main properties of solvents that affect the extraction process. The best extractants for the rhamnolipids isolation from cultural liquid supernatant of the Pseudomonas sp. PS-17 strain are the ethers. It can be explained by the presence of a lone pair of the electrons of oxygen in its molecule. The obtained results of the study are of scientific interest for isolation of the important and perspective biotechnological products – surface-active substances.

Diagnosis of hydrous ethanol combustion in a spark-ignition engine

2020 ◽  
Vol 235 (1) ◽  
pp. 245-259
Author(s):  
Caio H Rufino ◽  
Waldyr LR Gallo ◽  
Janito V Ferreira
Keyword(s):  
Engine Speed ◽  
Combustion Characteristics ◽  
Spark Ignition Engine ◽  
Ignition Timing ◽  
Operational Parameters ◽  
Fuel Ratio ◽  
Combustion Duration ◽  
Wide Range ◽  
Hydrous Ethanol ◽  
The Relationship

By evaluating combustion duration and flame development, it is possible to evaluate the effects of utilizing a new type of fuel. This allows for optimization of the operational parameters such as the ignition timing, air–fuel ratio, and throttle opening with respect to efficiency, knock, emissions, and performance. In this work, the combustion of a Brazilian hydrous ethanol fuel was evaluated in a commercial flexfuel engine. Investigations were conducted by performing a heat release analysis of the experimental data and providing combustion characteristics. The experimental design comprised of variations in engine speed, load, ignition timing, and air–fuel ratio under lean condition. The results indicated the relationship between the engine parameters and combustion characteristics under a wide range of operational conditions, and identified the relationship between the physical characteristics of the fuels and their combustion in the commercial engine. For high engine speed, lean combustion presented a similar duration to the stoichiometric combustion duration. When comparing the combustion characteristics obtained for the hydrous ethanol with gasoline combustion, the main differences noted were reduced sensitivity to detonation and a shorter duration of combustion, although the temperature at the start of combustion was lower for ethanol. In addition to shorter combustion duration, ethanol presented a lower value for the Wiebe exponent. The results obtained from the combustion duration values and Wiebe function parameters enable the composition of a set of data required for a simplified combustion simulation.

scholarly journals Microwave-Assisted Industrial Scale Cannabis Extraction

Technologies ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 45
Author(s):  
Marilena Radoiu ◽  
Harmandeep Kaur ◽  
Anna Bakowska-Barczak ◽  
Steven Splinter
Keyword(s):  
Continuous Flow ◽  
Extraction Efficiency ◽  
Scale Up ◽  
Extraction Process ◽  
Extraction Methods ◽  
Flowering Plant ◽  
Industrial Scale ◽  
Microwave Assisted ◽  
Operation Conditions ◽  
Assisted Extraction

Cannabis is a flowering plant that has long been used for medicinal, therapeutic, and recreational purposes. Cannabis contains more than 500 different compounds, including a unique class of terpeno-phenolic compounds known as cannabinoids. Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are the most extensively studied cannabinoids. They have been associated with the therapeutic and medicinal properties of the cannabis plant and also with its popularity as a recreational drug. In this paper, an industrial method for cannabis extraction using 915 MHz microwaves coupled with continuous flow operation is presented. The main advantages of the microwave-assisted extraction (MAE) are associated to the continuous-flow operation at atmospheric pressure which allows for higher volumes of biomass to be processed in less time than existing extraction methods, with improved extraction efficiency leading to increased final product yields, improved extract consistency and quality because the process does not require stopping and restarting material flows, and ease of scale-up to industrial scale without the use of pressurised batch vessels. Moreover, due to the flexibility of changing the operation conditions, MAE eliminates additional steps required in most extraction methods, such as biomass decarboxylation or winterisation, which typically adds at least a half day to the extraction process. Another factor that sets MAE apart is the ability to achieve high extraction efficiency, i.e., up to 95% of the active compounds from cannabis biomass can be recovered at industrial scale.

scholarly journals Attribute Reduction in Soft Contexts Based on Soft Sets and Its Application to Formal Contexts

Mathematics ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 689
Author(s):  
Won Keun Min
Keyword(s):  
Attribute Reduction ◽  
Extraction Process ◽  
Formal Context ◽  
Soft Sets ◽  
Step Method ◽  
The Relationship

We introduce the notion of the reduct of soft contexts, which is a special notion of a consistent set for soft contexts. Then, we study its properties and show that this notion is well explained by the two classes, 1 0 and 2 0 , of independent attributes. In particular, we describe in detail how to extract a reduct from a given consistent set. Then, based on this extraction process, we propose a six-step method for constructing a reduct from a given consistent set. Additionally, to apply this method to formal contexts, we examine the relationship between the reducts of a given formal context and the reducts of the associated soft context. We finally illustrate the process of obtaining reducts in a formal context using this relationship and the six-step method using an example.

Cooling Process for Precipitation Strengthening of Vanadium in Ferrite

2012 ◽  
Vol 706-709 ◽  
pp. 2078-2083
Author(s):  
Xiao Hui Cai ◽  
Zhen Yu Liu ◽  
Guo Dong Wang
Keyword(s):  
Solid Solution ◽  
Nitrogen Content ◽  
Dislocation Line ◽  
Precipitation Strengthening ◽  
Solution Temperature ◽  
Precipitation Process ◽  
Cooling Process ◽  
Coiling Temperature ◽  
Parabolic Curve ◽  
The Relationship

The precipitation of vanadium takes place mainly in ferrite by interphase precipitation or nucleation on dislocation line, which makes sense for the industry production due to the precipitation strengthening. The objective is to analysize the cooling process of V-steels to exert the precipitation strengthening of vanadium. The steels with 0.09%C-0.055%N/0.0107%N/0.0168%N/0.0193%N-0.08%V/0.085V steel are the researched steel grades. Using solid solubility products model and thermodynamic equation, the full solid solution temperature, nucleation rate curve and PTT curve of precipitation process are calculated. The effect of nitrogen on the precipitation behaviour of V(C,N) in γ and the precipitation of V(C,N) in α are simulated. Based on the calculation results the trial process is determined. The laboratorial trials are carried out with ultra fast cooling. The precipitate particles are observed by TEM. The solid solution amount increases monotonously and the size of precipitate particle decreases with the nitrogen content. The solid solution temperature of 0.055%N, 0.0107%N, 0.0168%N and 0.0193%N are 977.0°C, 1028.0°C, 1062.3 and 1078.9°C respectively. The laboratorial trial results shows that the tensile strength is improved about 100 MPa due to the precipitation strengthening. The relationship between the coiling temperature and the strength is parabolic curve downward and the relationship between the coiling temperature and the elongation is parabolic curve upward. This calculation can determine both the proper nitrogen content and the optimal cooling process. The trial results proves this method is feasible and efficiency.

scholarly journals Microwave Extraction vs. Other Techniques for Industrial Scale Cannabis Extraction

2020 ◽  
Author(s):  
Marilena Radoiu ◽  
Harmandeep Kaur ◽  
Anna Bakowska-Barczak ◽  
Steven Splinter
Keyword(s):  
Continuous Flow ◽  
Extraction Efficiency ◽  
Scale Up ◽  
Extraction Process ◽  
Extraction Methods ◽  
Flowering Plant ◽  
Industrial Scale ◽  
Active Compounds ◽  
Operation Conditions ◽  
Assisted Extraction

Cannabis is a flowering plant that has long been used for medicinal, therapeutic, and recreational purposes. Cannabis contains more than 500 different compounds, including a unique class of terpeno-phenolic compounds known as cannabinoids; Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are the most prevalent cannabinoids and have been associated with the therapeutic and medicinal properties of the cannabis plant. In this paper, continuous flow microwave assisted extraction (MAE) is presented and compared with other methods for commercial cannabis extraction. The practical issues of each extraction method are discussed. The main advantages of MAE are: continuous-flow method which allows for higher volumes of biomass to be processed in less time than existing extraction methods, improved extraction efficiency leading to increased final product yields, improved extract consistency and quality because the process does not require stopping and restarting material flows, and ease of scale-up to industrial scale without the use of pressurised batch vessels. Moreover, due to the flexibility of changing the operation conditions, MAE eliminates additional steps required in most extraction methods, such as biomass decarboxylation, winterisation, which typically adds at least a half day to the extraction process. Another factor that sets MAE apart is the ability to achieve high extraction efficiency even at the industrial scale. Whereas the typical recovery of active compounds using supercritical CO¬2 remains around 70-80%, via MAE up to 95% of the active compounds from cannabis biomass can be recovered at the industrial scale.

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