The Calculus of the Operation Parameters at Pressure of the Primary Separation Column of the 15N Production Plant

2017 ◽  
Vol 68 (11) ◽  
pp. 2533-2537
Author(s):  
Damian Axente ◽  
Ancuta Balla ◽  
Stefan Bugeac ◽  
Mihai Gligan ◽  
Cristina Marcu
Keyword(s):  
Molar Fraction ◽  
Theoretical Plate ◽  
Production Plant ◽  
Transfer Velocity ◽  
Solution Flow ◽  
Hno3 Solution ◽  
Flow Rates ◽  
Separation Column ◽  
Primary Separation ◽  
Column Product

The relations for calculus of: 10M HNO3 solution flow, isotopic transport, 15N molar fraction at the bottom of the separation column, product flow, interphasic transfer velocity, height equivalent to the theoretical plate and sulfur dioxide flows in both stages of the product refluxer are presented for 15N separation column with different diameters and 10M HNO3 feeding flow rates, operated at pressure up to 1.5 atm. In order to produce the isotope 15N at 99 at. % 15N by isotopic exchange in Nitrox system it is desirable to operate the production plant at biggest flow of 10M HNO3 solution, which allows the 15N production at that concentration on a given plant. That will be possible by operating the plant at pressure as it is shown in this work. At 0.8 atm pressure (1.8 atm absolute) the isotopic separation at higher flow rates would be practically equal with that obtained at lower flow rates and atmospheric pressure. For constant: HETP = 10.85 cm, 15N molar fraction of the feeding 10M HNO3, Nf = 0.00365, and of the product, Np = 0.12, the variation of the primary separation column product and of the 15N production plant, as a function of the feeding flow with 10M HNO3 solution, are also presented.

scholarly journals Head lettuce production and nutrition in relation to nutrient solution flow

2020 ◽  
Vol 38 (1) ◽  
pp. 21-26
Author(s):  
Cleiton Dalastra ◽  
Marcelo CM Teixeira Filho ◽  
Marcelo R da Silva ◽  
Thiago AR Nogueira ◽  
Guilherme Carlos Fernandes
Keyword(s):  
Nutrient Solution ◽  
Flow Rate ◽  
Nutrient Accumulation ◽  
Solution Flow ◽  
Flow Rates ◽  
Hydroponic System ◽  
Optimum Flow Rate ◽  
Technical Performance ◽  
Use Efficiency ◽  
Optimum Flow

ABSTRACT The optimum flow rate of nutrient solution in hydroponic system can better nourish the crops, allowing healthy and faster growth of lettuce. However, flow also interferes with electric power consumption, so further researches are necessary, mainly on the effect of flow rate, nutrient accumulation and lettuce production. In this context, the aim of this study was to evaluate nutrition and production of head lettuce in relation to the nutrient solution flow in NFT hydroponic system. The treatments consisted of nutrient solution application at the flow rates 0.5; 1; 2, and 4 liters per minute in each cultivation channel. Five replicates per treatment consisted of 15 plants each. The flow in hydroponic systems to produce head lettuce alters the technical performance of the crop. Due to the greater nutrient accumulation in shoot and use efficiency of these elements, the highest production (g/plant) of head lettuce was obtained with a flow rate of 1 L/min of the nutrient solution.

scholarly journals Turbulent Kinetic Energy Distribution of Nutrient Solution Flow in NFT Hydroponic Systems Using Computational Fluid Dynamics

2019 ◽  
Vol 1 (2) ◽  
pp. 283-290
Author(s):  
Cesar H. Guzmán-Valdivia ◽  
Jorge Talavera-Otero ◽  
Omar Désiga-Orenday
Keyword(s):  
Fluid Dynamics ◽  
Kinetic Energy ◽  
Energy Distribution ◽  
Turbulent Kinetic Energy ◽  
Nutrient Solution ◽  
Kinetic Energy Distribution ◽  
Solution Flow ◽  
Flow Rates ◽  
Hydroponic System ◽  
Hydroponic Systems

Hydroponics is crucial for providing feasible and economical alternatives when soils are not available for conventional farming. Scholars have raised questions regarding the ideal nutrient solution flow rate to increase the weight and height of hydroponic crops. This paper presents the turbulent kinetic energy distribution of the nutrient solution flow in a nutrient film technique (NFT) hydroponic system using the computational fluid dynamics (CFD) method. Its main objective is to determine the dynamics of nutrient solution flow. To conduct this study, a virtual NFT hydroponic system was modeled. To determine the turbulent kinetic energy distribution in the virtual NFT hydroponic system, we conducted a CFD analysis with different pipe diameters (3.5, 9.5, and 15.5 mm) and flow rates (0.75, 1.5, 3, and 6 L min−1). The simulation results indicate that different pipe diameters and flow rates in NFT hydroponic systems vary the turbulent kinetic energy distribution of nutrient solution flow around plastic mesh pots.

scholarly journals Effect of Nutrient Solution Flow Rate on Hydroponic Plant Growth and Root Morphology

Plants ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1840 ◽  
Author(s):  
Bateer Baiyin ◽  
Kotaro Tagawa ◽  
Mina Yamada ◽  
Xinyan Wang ◽  
Satoshi Yamada ◽  
...  
Keyword(s):  
Plant Growth ◽  
Root Growth ◽  
Surface Area ◽  
Flow Rate ◽  
Root Morphology ◽  
Root Surface ◽  
Solution Flow Rate ◽  
Root Surface Area ◽  
Solution Flow ◽  
Flow Rates

Crop production under hydroponic environments has many advantages, yet the effects of solution flow rate on plant growth remain unclear. We conducted a hydroponic cultivation study using different flow rates under light-emitting diode lighting to investigate plant growth, nutrient uptake, and root morphology under different flow rates. Swiss chard plants were grown hydroponically under four nutrient solution flow rates (2 L/min, 4 L/min, 6 L/min, and 8 L/min). After 21 days, harvested plants were analyzed for root and shoot fresh weight, root and shoot dry weight, root morphology, and root cellulose and hemicellulose content. We found that suitable flow rates, acting as a eustress, gave the roots appropriate mechanical stimulation to promote root growth, absorb more nutrients, and increase overall plant growth. Conversely, excess flow rates acted as a distress that caused the roots to become compact and inhibited root surface area and root growth. Excess flow rate thereby resulted in a lower root surface area that translated to reduced nutrient ion absorption and poorer plant growth compared with plans cultured under a suitable flow rate. Our results indicate that regulating flow rate can regulate plant thigmomorphogenesis and nutrient uptake, ultimately affecting hydroponic crop quality.

scholarly journals Optimal Design of Safety Instrumented Systems for Pressure Control of Methanol Separation Columns in the Bisphenol A Manufacturing Process

2016 ◽  
Author(s):  
In-Bok Lee ◽  
Insung Woo
Keyword(s):  
Bisphenol A ◽  
Control Valve ◽  
Pressure Control ◽  
Production Plant ◽  
Relief Valve ◽  
Safety Integrity Level ◽  
Separation Column ◽  
Potential Risks ◽  
Separation Columns ◽  
Accident Scenarios

Bisphenol A production plant possesses considerable potential risks in the top of the methanol separation column, as pressurized acetone, methanol and water are processed at an elevated temperature, especially in the event of an abnormal pressure increase due to sudden power outage. This study assesses the potential risks in the methanol separation column through hazard and operability assessment and evaluates the damages in the case of fire and explosion accident scenarios. The study chooses three leakage scenarios: a 5-mm puncture on the methanol separation column, a 50-mm diameter fracture of a discharge pipe and a catastrophic rupture, and simulates using Phast (Ver. 6.531) the concentration distribution of scattered methanol, thermal radiation distribution of fires and overpressure distribution of vapor cloud explosions. Implementation of safety instrumented system equipped with two-out-of-three voting as a safety measure can detect overpressure at the top of the column and shut down the main control valve and the emergency shutoff valve simultaneously, all at the same time. By applying safety integrity level of three, the maximal release volume of the safety relief valve can be reduced and therefore, the design capacity of the flare stack can also be reduced. Such integration will lead to improved safety at a reduced cost.

Studies on Citronellal Extract Column Reflux Ratio and Theoretical Plate Number Design

2013 ◽  
Vol 773 ◽  
pp. 331-335
Author(s):  
Zheng Hui Zhang ◽  
Qiu Chen
Keyword(s):  
Process Design ◽  
High Vacuum ◽  
Theoretical Plate ◽  
Reflux Ratio ◽  
Graphic Method ◽  
Relational System ◽  
Plate Number ◽  
Operation Process ◽  
Theoretical Plate Number ◽  
Column Product

In this paper, the batch rectification operation is adopted to keep distillate constituting constant high vacuum, in the operation process, the operation of variable reflux ratio is carries out. Through studying the relational system of reflux ratio, column top product composition, rectification time and theoretical plate number, when the concentration of citronellal extract column product is 99%, the appropriate reflux ratio is 0.8-15, and the graphic method is used to design13 pieces of theoretical plate number of citronellal extract column, providing powerful data support for the process design of citronellal extract column.

Metabolic rate and thermal stability during honeybee foraging at different reward rates

2001 ◽  
Vol 204 (4) ◽  
pp. 759-766 ◽  
Author(s):  
L. Moffatt
Keyword(s):  
Thermal Stability ◽  
Metabolic Rate ◽  
Flow Rate ◽  
Sucrose Solution ◽  
Carbon Dioxide Production ◽  
Metabolic Power ◽  
Solution Flow ◽  
Flow Rates ◽  
Metabolic Heat ◽  
Air Temperatures

During honeybee foraging, the stabilization of thoracic temperature (Tth) at elevated values is necessary to meet the power requirements of flight at different air temperatures (T(a)). To understand how the bee achieves thermal stability at different reward rates, the metabolic rates of undisturbed foraging bees were measured at different T(a) values and different sucrose solution flow rates. Metabolic heat production, calculated from the rate of carbon dioxide production, decreased linearly from 49.7 to 23.4 mW as T(a) increased from 19 to 29 degrees C (sucrose flow rate 1.75 microl × min(−1), 50 % w/w). In contrast, crop load and inspection rate remained constant. Metabolic rate displayed a linear relationship with both T(a) and the logarithm of the flow rate of sucrose solution (range analyzed 0.44-13.1 microl × min(−1), 50 % w/w). Metabolic rate decreased by 3.13+/−0.52 mW (mean +/− s.e.m., N=37) for every 1 degrees C increase in T(a) and increased by 4.36+/−1.13 mW for a doubling in flow rate. These changes in metabolic power output might be used to achieve thermal stability during foraging. It is suggested that the foraging bee might increase its Tth in accordance with the reward rate.

DEVELOPMENT OF AN ELECTRONIC AEROSOL SYSTEM FOR GENERATING MICROCAPSULES

2016 ◽  
Vol 78 (5-7) ◽  
Author(s):  
Wai Yean Leong ◽  
Chin Fhong Soon ◽  
Soon Chuan Wong ◽  
Kian Sek Tee
Keyword(s):  
Sodium Alginate ◽  
Air Flow ◽  
Electronic System ◽  
Syringe Pump ◽  
Air Flow Rate ◽  
Solution Flow ◽  
Flow Rates ◽  
Encapsulation Process ◽  
Compact Design ◽  
Simple Economic

The encapsulation of living cells in a variety of soft polymers or hydrogels is important, particularly for the generation of microtissues. Various techniques have been developed for the production of microcapsules to encapsulate cells but presented threat to the cells due to the harsh treatment during the encapsulation process.  In this paper, we propose a simple, economic and compact design of aerosol electronic system for producing different sizes of microcapsules. The aerosol system was developed with the incorporation of a conventional syringe pump and a customised air pump. The syringe pump purged the droplets of sodium alginate and air pump dispersed the droplets into microdroplets of sodium alginate which was then polymerised in the calcium chloride solution. In this system, the air flow rate from the air pump was controlled by a programmed microcontroller that received input instructions from a potentiometer. The suitable air flow rates that worked synchronously with the speed of the syringe pump were characterised. At 0.2 and 0.3 L/min of air flow and 20 µl/min of alginate solution flow, this device successfully generated round microcapsules with various sizes ranging from 100 to 350 µm.

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