scholarly journals Ammoniacal Carbonate Leaching: Effect of Dissolved Sulfur in the Distillation Operation

2020 ◽  
Vol 67 (4) ◽  
pp. 1239-1249
Author(s):  
Armando Rojas Vargas ◽  
María Elena Trujillo Nieve ◽  
Yudith González Diaz
Keyword(s):  
Energy Consumption ◽  
Distillation Process ◽  
Calcination Process ◽  
Filtration Resistance ◽  
Cake Moisture ◽  
Sulfur Effect ◽  
Rich Solution ◽  
Sulfate Formation ◽  
The Mean ◽  
Carbonate Leaching

The distillation process in the Ammoniacal Carbonate Leaching technology was studied at bench-scale and on industrial scale. The dissolved sulfur effect in the Product-liquor that feeds to the columns, on the Basic Nickel Carbonate (BNC) properties and the operation expenses was determined. When increasing the sulfur in the liquor, we augment the selectivity towards the sulfate formation in the BNC molecule; therefore the energy consumption to the BNC thermal decomposition in the calcination process increases. Also, the nickel dissolved in the columns effluent increases due to complex reaction with [SO42–] and [S2O32–] ions, thus the expenses for consumption precipitation reagent increase too. Feeding carbonated liquor in the range 1.60 ≤ NH3/CO2 < 1.80 and CO2-rich solution increases the CO2 in the BNC with decreasing in sulfate; then, the mean diameter particle increases, the filtration resistance and the cake moisture diminish, which augments the productivity and reduces the energy consumption in the process of filtration and calcination. Keeping a pH between 8.4 and 8.7 in the columns outlet the greatest economic benefit is obtained of 0,125 ($ · h–1) per (m3 · h–1) of Product-liquor.

Precipitation and filtration of zinc, magnesium, copper and aluminium hydroxides

1982 ◽  
Vol 47 (12) ◽  
pp. 3362-3370
Author(s):  
Otakar Söhnel ◽  
Eva Matějčková
Keyword(s):  
Residence Time ◽  
Mean Residence Time ◽  
Filtration Resistance ◽  
Filtration Pressure ◽  
Bed Porosity ◽  
The Mean ◽  
Filtration Properties

Filtration properties of batchwise precipitated suspensions of Zn(OH)2, Mg(OH)2 and Cu(OH)2 and continuously precipitated Al(OH)3 were studied. For batchwise precipitated suspensions was verified the theoretically predicted dependence of specific filtration resistance on initial supersaturation and for the continuously precipitated Al(OH)3 the relation between the specific filtration resistance and the mean residence time of suspension in the reactor. Dependences were also recorded between the bed porosity and concentration of precipitated solutions, specific filtration resistance and used filtration pressure and the effect of aging of the batchwise precipitated suspension of Mg(OH)2on its filtration properties. The used CST method for determination of filtration characteristics of Zn(OH)2 suspension was also studied.

Familial pseudohyperkalaemia: Inhibition of erythrocyte K+ efflux at 4°C by quinine

1987 ◽  
Vol 73 (5) ◽  
pp. 557-560 ◽  
Author(s):  
David R. James ◽  
David Stansbie
Keyword(s):  
Energy Consumption ◽  
Glucose Consumption ◽  
K Channel ◽  
Inappropriate Treatment ◽  
The Mean

1. Mechanisms responsible for increased erythrocyte K+ efflux in vitro have been investigated in a patient with familial pseudohyperkalaemia. Mean net K+ efflux (4°C) was 108 nmol h−1 10−9 erythrocytes, seven times greater than the mean for controls (15.2 nmol h−1 10−9 erythrocytes). Net K+ efflux was not increased at 22°C or 37°C and losses at 4°C were reversed by subsequent incubation at 37°C. 2. Erythrocyte glucose consumption (4°C) was 14 nmol h−1 10−9 erythrocytes, similar to the mean for controls of 16.8 nmol h−1 10−9 erythrocytes. This suggests that the increased net K+ efflux (4°C) was not associated with abnormal energy consumption and was therefore unlikely to be due to an abnormality of the Na+, K+-pump. 3. Incubation of erythrocyte suspensions with ouabain (0.1 mmol/l) or frusemide (1 mmol/l) at 4°C or 37°C resulted in no differences in K+ efflux between patient and controls. Incubation with quinine (2 mmol/l), an inhibitor of the erythrocyte Ca2+-dependent K+ channel, reduced net K+ efflux at 4°C, but the effect persisted in Ca2+-depleted erythrocytes, implying that quinine was acting in a non-specific fashion. 4. Chemical pathologists and clinicians must be aware of this condition if inappropriate treatment of pseudohyperkalaemia is to be avoided.

Energy consumption prediction in cement calcination process: A method of deep belief network with sliding window

Energy ◽  
2020 ◽  
Vol 207 ◽  
pp. 118256
Author(s):  
Xiaochen Hao ◽  
Tongtong Guo ◽  
Gaolu Huang ◽  
Xin Shi ◽  
Yantao Zhao ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Sliding Window ◽  
Deep Belief Network ◽  
Calcination Process ◽  
Belief Network ◽  
Energy Consumption Prediction ◽  
Consumption Prediction

scholarly journals In Situ Monitoring of Drying Process of Masonry Walls

Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6190
Author(s):  
Łukasz Cieślikiewicz ◽  
Piotr Łapka ◽  
Radosław Mirowski
Keyword(s):  
Energy Consumption ◽  
Moisture Content ◽  
Thermal Behavior ◽  
Specific Energy Consumption ◽  
Masonry Wall ◽  
In Situ Monitoring ◽  
Drying Process ◽  
Final State ◽  
The Mean

The in situ hygro-thermal behavior of a wet masonry wall during its drying process is presented in this paper. The considered wall is a part of a basement of a historic building that was subjected to renovation works. The building is located in the City of Łowicz (Poland). The drying process was implemented by applying the thermo-injection method and a novel prototype of the drying device used for this method. The dedicated acquisition system was developed to in situ monitor parameters of the drying process. The air temperature and relative humidity in various locations in the basement, temperatures and moisture contents at several points of the wet wall as well as the electrical parameters of the drying device were registered. Based on variations of the monitored parameters, the hygro-thermal behavior of the wall during drying was studied. After 6 days of drying, the wall temperature in the drying zone was increased to approximately 40–55 °C, while the moisture content was reduced to the mean level of 3.76% vol. (2.35% wt.). These wall parameters allowed for effective impregnation of the wall with the hydrophobic silicone micro-emulsion, which created horizontal and vertical waterproofing. Moreover, the specific energy consumption during the drying process defined as energy consumption divided by the mean volumetric moisture content drop (MC) between the initial and final state in the wall and by the length of the dried wall section was estimated to be 11.08 kWh/MC%/m.

Discussion on the Design of Freezing Dehumidification-Based Radiant Air-Conditioning System

2012 ◽  
Vol 204-208 ◽  
pp. 4274-4279
Author(s):  
Chao Yi Tan ◽  
Han Qing Wang ◽  
Hui Zhu
Keyword(s):  
Energy Consumption ◽  
Air Conditioning ◽  
Design Method ◽  
Load Ratio ◽  
Design Parameters ◽  
Air Conditioning System ◽  
Comfort Index ◽  
Low Energy Consumption ◽  
The Mean ◽  
Approximation Calculation

For the purpose of realizing non-dewfall condition of the radiant panels, low energy consumption and nice comfort of the freezing dehumidification-based radiant air-conditioning system, the design temperature and humidity of the room were figured out according to the mean comfort index of human body during the design. And in order to lower the energy consumption, the necessity of the reasonable load allocation between the dehumidification unit and the radiant unit was discussed by means of the calculation with the quasi heat-humidity-ratio line. As a result, much more precise design parameters were acquired through the approximation calculation. And it was proven to be a good design method by applying these parameters to the design of the reading rooms of the library. In the design example of the reading room, the load ratio between the dehumidification unit and the radiant unit was 48 to 52, and the recirculation air flow rate of the dehumidification unit was not less than 36.8% of the total air rate of the room.

scholarly journals Effects of Preoperative Oral Carbohydrate Loading on Preoperative and Postoperative Comfort in Patients Planned to Undergo Elective Cholecystectomy: A Prospective Randomized Controlled Clinical Trial

2020 ◽  
Keyword(s):  
Controlled Clinical Trial ◽  
Fasting Period ◽  
Rich Solution ◽  
The Mean ◽  
Group 2 ◽  
American Society ◽  
American Society Of Anesthesiologists ◽  
Elective Cholecystectomy ◽  
Group 1 ◽  
Operational Time

Background: Cholecystectomy is a widespread abdominal procedure. A period of 8-hour-fasting for this relatively rapid surgery negatively affects the patients’ comfort. Objectives: The current study aimed to evaluate the effects of the presurgical intake of carbohydrate on patients’ comfort. Materials and Methods: This prospective study was carried out on 42 cholecystectomy patients (with the American Society of Anesthesiologists grade of I-II) divided into two groups. The patients in group 1 underwent laparoscopic cholecystectomy after an 8-hour-fasting period. The subjects in group 2 received a carbohydrate-rich solution with 12.5% dextrose before the surgery (125 g of sugar melted in 1 L of water; 800 and 200 mL 8 and 2 h before the surgery, respectively). Thirst, hunger, and nausea at the 9th preoperative hour and 30 min before the surgery in addition to nausea and vomiting at the 2nd, 8th, and 24th postoperative hours were assessed in both groups. Results: The mean age and body mass index (BMI) values of the patients were 48.38±12.68 years and 29.85±5.20 kg/m², respectively. The mean operational time was 36.5 min (range: 26-114 min). No difference was observed between the two groups in terms of age, BMI, and operational time. The investigation 30 min before cholecystectomy revealed that the rates of hungry and thirsty patients were higher in group 1, compared to those reported for group 2 (P=0.003 and P=0.032). Nevertheless, at the 2nd and 8th postoperative hours, the rate of patients complaining of nausea were higher in group 2 in comparison to that of group 1 (P=0.048 and P=0.014). Conclusions: It is suggested that the intake of carbohydrate-rich fluids up to the preoperative 2nd hour decreased presurgical hunger/thirst. The results of this study are in line with the findings of previous studies. It is believed that the intake of CHO-rich solutions up to 2 h before surgery may provide comfort by decreasing hunger/thirst. Nevertheless, it is necessary to take into account a potential rise in a feeling of nausea among these patients.

Evaluation on energy consumption in compact hydro distillation process between MPC and PID control

2017 ◽  
Author(s):  
Nurul Nadia Mohammad ◽  
Ahmad Aftas Azman ◽  
Mohd Hezri Marzaki ◽  
Ramli Adnan ◽  
Mohd Hezri Fazalul Rahiman ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Pid Control ◽  
Distillation Process

Development and Testing of the Power Transmission System of a Crawler Electric Tractor for Greenhouses

2020 ◽  
Vol 36 (5) ◽  
pp. 797-805
Author(s):  
Jing Liu ◽  
Changgao Xia ◽  
Donglin Jiang ◽  
Yan Sun
Keyword(s):  
Energy Consumption ◽  
Internal Combustion Engines ◽  
Power Transmission ◽  
Transmission System ◽  
Operating Efficiency ◽  
List Type ◽  
The Core ◽  
Power Transmission System ◽  
Core Components ◽  
The Mean

HighlightsBuilt a functional electric drive system of a crawler tractor for greenhouses.Properly integrated the electric components into a traditional tractor.Performed field rotary tillage, field transport, and plowing energy consumption tests to verify the correctness of the matching of the core components of the power transmission system and some performance of the prototype crawler electric tractor.Abstract. Greenhouses are among the most rapidly developing sectors of the Chinese agricultural industry, and they require considerable mechanization. Currently, the machinery used in greenhouses mainly include micro cultivators powered by internal combustion engines. The micro cultivators have various problems such as small output power, low operating efficiency, and poor quality. Also, they harm the growth environment of crops and the working environment of farmers due to gas emissions and noise. In this study, a crawler electric tractor suitable for greenhouses is proposed. It can function in small working areas and narrow working spaces. The electric tractor is suitable for towing, transportation, lifting, and power output. A power transmission system scheme was designed for the electric tractor and a parameter matching method for the core components of the power transmission system is proposed. The prototype of the electric tractor was manufactured and underwent field rotary tillage, field transport, and plowing energy consumption tests. The results of rotary tillage and transportation testing showed that the operating parameters such as the depth and width of rotary tillage and transportation speed met the design requirements, which validated the matching of core components of the power transmission system and the operating performance of the prototype crawler electric tractor. The mean rotary tillage depths of the prototype on the left side and the right side are 11.0 and 12.1 cm, respectively. The mean width is 113 cm. The mean speed of rotary tillage is 4.99 km h-1. The measured speed of the prototype in the field is within the speed demand range at gears I, II, and III. According to the results of plowing energy consumption test, the mean electrical energy consumption of plowing one mu of land was 5.60 kW h mu-1, which showed that the prototype crawler electric tractor had good economic performance. To sum up, the prototype of the electric tractor for greenhouses manufactured is economic and practical. Keywords: Electric tractor, Facility agriculture, Field test, Power transmission.

Effect of Zinc Sulfate on Human Primary Enamel Microhardness: An in vitro Study

2012 ◽  
Vol 36 (4) ◽  
pp. 369-371 ◽  
Author(s):  
M Mirkarimi ◽  
M Bargrizan ◽  
S Eskandarion ◽  
M Shahsavari
Keyword(s):  
Zinc Sulfate ◽  
Artificial Saliva ◽  
In Vitro Study ◽  
Hardness Test ◽  
Knoop Hardness ◽  
Control Group ◽  
Expected Time ◽  
Rich Solution ◽  
The Mean

Objective: The aim of this study was to assess the effect of zinc sulfate on microhardness of human primary enamel. Method: Sixteen sound primary molars were sectioned mesiodistally. For each sample one of the sections was randomly immersed in artificial saliva (Biotene,USA) and the other was immersed in artificial saliva which was charged with 10 mg/5mL concentration of zinc sulfate supplement (Razak Company, Iran) daily. After 24 days (the expected time to use up one 120-mL bottle) the surface microhardness of enamel was measured by knoop hardness test (KH) with Knoop diamond under a 50-gram load for 10 seconds. Results: The mean (± SD) microhardness values (KHV) for the tested groups were 320 ± 49.45 and 357 ± 36.35, respectively. There were statistically significant differences between the groups as exhibited by independent t-test (P=0.023). Conclusion: Primary teeth immersed in a zinc sulfate rich solution for 24 days showed higher microhardness values in comparison with the control group.

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