Transportation of Sulfuric Acid with Vacuum Unit

2021 ◽  
pp. 81-90
Author(s):  
N.L. Velikanov ◽  
V.A. Naumov
Keyword(s):  
Sulfuric Acid ◽  
Energy Consumption ◽  
Performance Indicators ◽  
Solution Concentration ◽  
Vacuum System ◽  
Humid Air ◽  
Pumping Rate ◽  
Different Temperatures ◽  
Vacuum Systems ◽  
Aggressive Liquid

In the chemical industry, for example, in the production of sulfuric acid and the movement of sulfur recovered in refineries, the temperature of liquid substances can vary widely. The study of the effect of aggressive liquid temperature and concentration on the productivity and energy efficiency of vacuum systems for transporting liquids has been carried out. The performance (dry air pumping rate) and the consumed power of the vacuum pump ZhVN-12N depending on the pressure in the working chamber are considered. The correction coefficients of productivity for pumping out humid air have been determined for different temperatures. The performance indicators of a vacuum system for transporting liquids based on ZhVN-12N have been investigated. It was found that an increase in the temperature of the pumped humid air increases the average productivity of the vacuum system for transporting liquids, reducing its energy consumption. It is shown that an increase in the sulfuric acid solution concentration results in a decrease in productivity and an increase in the energy consumption of the vacuum system, while the efficiency decreases slightly.

Design of Vacuum System of Steam Jet Bursting Unit for Chestnut Shell

2011 ◽  
Vol 291-294 ◽  
pp. 1685-1688
Author(s):  
Xi Nan Dang ◽  
Qiao Fu Chen ◽  
Li Jun Yang
Keyword(s):  
Energy Consumption ◽  
Vacuum System ◽  
Jet Pump ◽  
Waste Gas ◽  
System A ◽  
Start Up ◽  
Chestnut Shell ◽  
Bursting Process

According to the vacuum bursting process for fresh chestnut shell and requirements for relevant vacuum system, a vacuum system of steam jet pump was designed with a start-up jet pump attached to it. Of which the waste gas from ejector was used for reheating in the bursting process to lead the vacuum bursting unit to run more reliably and stably with efficiency improved and energy consumption reduced. The rate of bursting came up to 95% in the process test.

scholarly journals Acid and Temperature Treatments Result in Increased Germination of Seeds of Three Fescue Species

2012 ◽  
Vol 40 (2) ◽  
pp. 220 ◽  
Author(s):  
Rade S. STANISAVLJEVIC ◽  
Savo M. VUCKOVIC ◽  
Aleksandar S. SIMIC ◽  
Jordan P. MARKOVIC ◽  
Zelijco P. LAKIC ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Seed Germination ◽  
Acid Solution ◽  
Sulfuric Acid Solution ◽  
Germination Rate ◽  
Festuca Rubra ◽  
Time Intervals ◽  
Different Temperatures ◽  
Successful Establishment ◽  
Seed Collecting

Efficient germination of fescue seeds is essential for successful establishment of meadows and pastures. This research was conducted to ascertain the effects of various acid and temperature treatments on seed germination in three fescue species: Festuca rubra, F. ovina, and F. pratensis. Seeds from different cultivars, populations, or lots were exposed either to four concentrations of sulfuric acid at three different time intervals (12 treatments) or six different temperatures at three different time intervals (18 treatments). Despite all belonging to the genus Festuca, the seed from different species responded differently to the treatments. The three optimum treatments for F. rubra seed involved soaking in a 75% solution of sulfuric acid for 20 minutes (improved the germination rate by 19%), soaking in a 50% solution of sulfuric acid for 30 minutes (improved the germination rate by 18%) and exposure to either 60°C or 70°C for 90 minutes (improved the germination rate by 17%). For F. ovina seed, optimal treatments included soaking seeds for either 10 or 20 minutes in a 50% sulfuric acid solution (both treatments improved germination rates by 13%) or exposing seeds for 30 minutes in a 25% sulfuric acid solution and 80°C for 60 minutes (improved germination rate by 12%). Two optimal treatments were identified for F. pratensis seed. Whereas the first involved soaking the seeds in a 75% sulfuric acid solution for 30 minutes (improved germination rates by 22%), the second involved either exposing the seeds to 90°C for 90 or 60 minutes, or exposing the seeds to 80°C for 90 minutes (improved germination rate by 21%). Our findings indicate that if fescue seed is to be sown during the autumn (two to three months after seed collecting), treating it with acid and temperature can significantly enhance its germination.

The decomposition of aliphatic N-nitro amines in aqueous sulfuric acid. Bisulfate as a nucleophile

1996 ◽  
Vol 74 (10) ◽  
pp. 1774-1778 ◽  
Author(s):  
Robin A. Cox
Keyword(s):  
Sulfuric Acid ◽  
Water Molecule ◽  
Rate Constants ◽  
Activation Parameters ◽  
Standard State ◽  
Aqueous Sulfuric Acid ◽  
Alkyl Groups ◽  
Different Temperatures ◽  
State Rate ◽  
Acid Catalyzed

In aqueous sulfuric acid, aliphatic N-nitro amines decompose to N2O and alcohols. An excess acidity analysis of the observed rate constants for the reaction shows that free carbocations are not formed. The reaction is an acid-catalyzed SN2 displacement from the protonated aci-nitro tautomer, the nucleophile being a water molecule at acidities below 82–85% H2SO4, and a bisulfate ion at higher acidities. Bisulfate is the poorer nucleophile by a factor of about 1000. Twelve compounds were studied, of which results obtained for nine at several different temperatures enabled calculation of activation parameters for both nucleophiles. The reaction appears to be mainly enthalpy controlled. The intercept standard-state rate constants are well correlated by the σ* values for the alkyl groups; the slopes are negative, with a more negative value for the slower bisulfate reaction. Interestingly the m≠m* slopes also correlate with σ*, although the scatter is bad. Key words: N-nitro amines, excess acidity, bisulfate, nucleophiles, acid-catalyzed, kinetics.

Scenario Based Method to Increase the Flexibility of Energy Use in Production Systems

2015 ◽  
Vol 805 ◽  
pp. 46-52 ◽  
Author(s):  
Eric Unterberger ◽  
Johannes Glasschröder ◽  
Gunther Reinhart
Keyword(s):  
Energy Consumption ◽  
Performance Indicators ◽  
Material Flow ◽  
Energy Use ◽  
Production Systems ◽  
Investment Decisions ◽  
Production Performance ◽  
Future Production ◽  
Scenario Technique

The paper presents a method to increase the energy flexibility of production systems, establishing a tool to increase the energy flexibility by using the scenario technique. First of all barriers and possible modifications to influence the energy consumption have to be identified. Afterwards, measures can be designed order to address these obstacles. Impacts of the energy conduct on the material flow and production performance indicators will be investigated. These results are necessary for investment decisions for future production plants.

The Effect of Ru on Unsupported Pt-Ru Alloys for Methanol Electro-Oxidation at Different Temperatures

1995 ◽  
Vol 393 ◽  
Author(s):  
Deryn Chu ◽  
Charles Walker ◽  
Sol Gilman
Keyword(s):  
Cyclic Voltammetry ◽  
Sulfuric Acid ◽  
Surface Area ◽  
Hydrogen Adsorption ◽  
X Ray Diffraction ◽  
X Ray ◽  
Different Temperatures ◽  
Adsorption Surface ◽  
Electro Oxidation ◽  
Bulk Alloys

ABSTRACTUnsupported different atomic ratios of platinum-ruthenium bulk alloys were prepared. The alloys were characterized by cyclic voltammetry, X-ray diffraction and energy dispersive X-ray spectroscopy. These alloys were also tested as anodes for methanol electro-oxidation in sulfuric acid over a range of temperatures. Ruthenium is inactive for methanol electro-oxidation at 25 °C, but becomes active at higher temperatures. When a comparison is made on the basis of “true” (hydrogen adsorption) surface area, a 30 atomic percent Ru electrocatalyst provides the highest activity for methanol electro-oxidation as measured at either 0.4 or 0.5V vs. RHE at both 25 and 60 °C.

Effect of Composition and Wall Thickness on Mechanical Properties of High Pressure Die Castings

2014 ◽  
Vol 790-791 ◽  
pp. 241-246
Author(s):  
Jenő Dúl ◽  
Zsolt Leskó
Keyword(s):  
Mechanical Properties ◽  
Computer Simulation ◽  
High Pressure ◽  
Wall Thickness ◽  
Vacuum System ◽  
Die Geometry ◽  
Experimental Tool ◽  
Preparation Phase ◽  
Die Castings ◽  
Vacuum Systems

In this paper we present two types of currently used vacuum systems on the HPDC and the preparation phase of an experimental tool. To investigate the properties of HPD castings we have designed a die geometry that complies with requirements of vacuum and non-vacuum systems. We used computer simulation to shape up the runner-and overflow-system. In the course of our work we examined specimens with differing thickness and alloys with different compositions to check the changes of mechanical properties and the effect of vacuum system.

Particle Behavior in Vacuum Systems: Implications for In-Situ Particle Monitoring in Semiconductor Processing Equipment.

1996 ◽  
Vol 39 (6) ◽  
pp. 40-48
Author(s):  
Patrick Kinney ◽  
Gwi-Nam Bae ◽  
David Pui ◽  
Benjamin Liu
Keyword(s):  
Semiconductor Industry ◽  
Simple Solution ◽  
Vacuum System ◽  
Spatial Distributions ◽  
Semiconductor Processing ◽  
Deposition Pattern ◽  
System Components ◽  
Vacuum Systems ◽  
Particle Monitoring

The flow of aerosol in vacuum conditions representative of many semiconductor processes (100 sccm, 1 Torr). was investigated. The study was performed using aerosols with highly nonuniform spatial distributions. An ideally nonuniform aerosol was produced by generating an aerosol beam using an aerodynamic lens. The flow containing the aerosol beam was drawn through vacuum system components. The size of the beam was measured upstream and downstream of these components by collecting the aerosol on a filter and observing the deposition pattern. Very little mixing phenomenon was observed. These results point to a potential limitation in the methods employed by the semiconductor industry for in-situ particle monitoring in vacuum systems. A simple solution to this flaw is suggested.

Residual Gas Phase Contamination of Al-Cu Alloy Films and its Effect on Electromigration Behavior

1996 ◽  
Vol 428 ◽  
Author(s):  
Imran Hashim ◽  
Ivo J. Raaijmakers ◽  
Glen Adler ◽  
Ardy Sidhwa ◽  
Sudhir Chopra
Keyword(s):  
Gas Phase ◽  
Physical Vapor Deposition ◽  
Target Material ◽  
Vacuum System ◽  
Al Alloy ◽  
Alloy Films ◽  
Cu Alloy ◽  
Effect Of Impurities ◽  
Residual Gas ◽  
Vacuum Systems

AbstractThe major sources of impurities in sputtered Al alloy films for interconnects, prepared by physical vapor deposition include those originating from the target material, residual gases present in the vacuum system, and those introduced through the gas delivery system. In this study, we report the effect of impurities incorporated from residual gases present in vacuum systems on the electromigration performance of 0.6 μm wide Al-l%Cu lines. Controlled leaks of isotope gases H2O18, N215, O218, and C13H4, in 10−6 10−9 Torr range, were introduced into a PVD tool during the sputtering process. Using these isotope gases, the impurities originating from residual gases were distinguished from those originating from other sources of impurities. The sputtering target was found to be the major source of H and O impurities in the film, whereas N atoms are introduced in the film mainly through the gas phase. Furthermore, N atoms in the film were found to affect its electromigration behaviour to a larger extent than O and H.

Eine Methode zur Messung geringster Ölbedeckungen in Vakuumsystemen

1967 ◽  
Vol 22 (4) ◽  
pp. 549-553 ◽  
Author(s):  
R. Dobrozemsky ◽  
W. K. Huber ◽  
F. Viehböck
Keyword(s):  
High Vacuum ◽  
High Sensitivity ◽  
Radioactive Tracer ◽  
Operating Conditions ◽  
Ultra High Vacuum ◽  
Vacuum System ◽  
First Results ◽  
Tracer Isotope ◽  
Radioactive Tracer Method ◽  
Vacuum Systems

To get information on extremely small organic deposits in ultra high vacuum systems the sensitivity of most of the conventional methods for thickness measurements is not high enough. On the other hand the radioactive tracer method has shown its high sensitivity and wide versatility in many fields. Tritium with a half life of 12.3 γ and a mean β-energy of 5.4 keV was choosen as tracer isotope. A method is described for Tritium-labelling diffusion pump oils with specific activities up to 100 mC/g. Using the liquid scintillation counting technique one can detect deposits down to below 1010 molecules/cm2. First results with this Tritium labelled pump fluid are given under different operating conditions in an all metal ultra high vacuum system.

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