Composition Profile of an Azeotropic Continuous Distillation with Feed Composition on a Ridge or in a Valley

1999 ◽  
Vol 38 (6) ◽  
pp. 2482-2484 ◽  
Author(s):  
Li ◽  
Chen ◽  
Liu
Keyword(s):  
Composition Profile ◽  
Feed Composition ◽  
Continuous Distillation

Decrease of energy demand of semi-batch distillation policies

2020 ◽  
pp. 0958305X2093331
Author(s):  
Mariem Ferchichi ◽  
Laszlo Hegely ◽  
Peter Lang
Keyword(s):  
Dynamic Simulation ◽  
Energy Demand ◽  
Ternary Mixtures ◽  
Liquid Volume ◽  
Direct Sequence ◽  
Batch Distillation ◽  
Feed Composition ◽  
Binary And Ternary Mixtures ◽  
Continuous Feeding ◽  
Continuous Distillation

Batch distillation (BD) has much higher energy demand than continuous distillation (CD). Different semi-batch distillation (SBD) policies, by which one part of the feed is continuously fed into a batch column, are investigated and optimised to minimise the energy demand. SBD has the advantage, that contrary to the batch distillation (BD), the liquid volume in the reboiler, can be kept constant, even at its maximal value. Usually, continuous feeding is performed into the reboiler (SBD1), but by shaping a feed plate in the batch column, it has not only a rectifying but also a stripping section. Several SBD policies differing in feeding location are studied by dynamic simulation and compared based on the specific energy demand (SED) of production. The different policies and effects of the variation of feed composition are studied for the separation of the mixture dichloromethane-acetone. The lowest SED is obtained by SBD with feeding at a variable location of the column (SBD3). However, feeding at a fixed location (SBD2) is much simpler to realise and only slightly inferior. Further reduction of SED is reached by using two SBD2 or one SBD2 and one BD step with different reflux ratios. The separation of the mixture n-hexane-n-heptane-n-octane is also studied by SBD1 and SBD2 policies with both direct and indirect sequences. The energy demand of SBD2 in indirect sequence is lower than that of the direct sequence by 25%. By applying SBD2, SED was reduced by 38% and 39% for binary and ternary mixtures, respectively, compared to BD.

scholarly journals The effect of valley and ridge on composition profile in an azeotropic continuous distillation column.

1983 ◽  
Vol 16 (1) ◽  
pp. 36-42 ◽  
Author(s):  
YUJI NAKA ◽  
KIKUO KOBAYASHI ◽  
HITOSHI OCHI ◽  
TAKEICHIRO TAKAMATSU
Keyword(s):  
Distillation Column ◽  
Composition Profile ◽  
Continuous Distillation

Interlayer mixing in GaAs/AlxGa1-xAs heterostructures as a result of Se+ ion implantation

1988 ◽  
Vol 46 ◽  
pp. 908-909
Author(s):  
E.G. Bithell ◽  
W.M. Stobbs
Keyword(s):  
Ion Implantation ◽  
Diffusion Coefficients ◽  
Dark Field ◽  
Atomic Mass ◽  
Composition Profile ◽  
Semiconductor Heterostructures ◽  
Transmission Electron ◽  
Microscope Images ◽  
Damage Process ◽  
Electron Energy Loss

It is well known that the microstructural consequences of the ion implantation of semiconductor heterostructures can be severe: amorphisation of the damaged region is possible, and layer intermixing can result both from the original damage process and from the enhancement of the diffusion coefficients for the constituents of the original composition profile. A very large number of variables are involved (the atomic mass of the target, the mass and energy of the implant species, the flux and the total dose, the substrate temperature etc.) so that experimental data are needed despite the existence of relatively well developed models for the implantation process. A major difficulty is that conventional techniques (e.g. electron energy loss spectroscopy) have inadequate resolution for the quantification of any changes in the composition profile of fine scale multilayers. However we have demonstrated that the measurement of 002 dark field intensities in transmission electron microscope images of GaAs / AlxGa1_xAs heterostructures can allow the measurement of the local Al / Ga ratio.

The effect of different extraction methods on chemical composition profile and pharmacological activities of essential oils and hydrosols

Planta Medica ◽  
2016 ◽  
Vol 81 (S 01) ◽  
pp. S1-S381
Author(s):  
F Ghavidel ◽  
MM Zarshenas ◽  
A Sakhteman ◽  
A Gholami ◽  
Y Ghasemi ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Essential Oils ◽  
Extraction Methods ◽  
Composition Profile ◽  
Pharmacological Activities

Body composition profile of patients with Duchenne muscular dystrophy living in a country with the obesity epidemic

2015 ◽  
Author(s):  
Artemis Doulgeraki ◽  
Marina Katsalouli ◽  
Glykeria Petrocheilou ◽  
Ioanna Paspati ◽  
Helen Athanasopoulou ◽  
...  
Keyword(s):  
Body Composition ◽  
Duchenne Muscular Dystrophy ◽  
Muscular Dystrophy ◽  
Composition Profile ◽  
Obesity Epidemic

Environmental impact of nutrients from nordic fish farming

1995 ◽  
Vol 31 (10) ◽  
pp. 61-71 ◽  
Author(s):  
M. Enell
Keyword(s):  
Major Part ◽  
Fish Farming ◽  
Fish Farms ◽  
Feed Composition ◽  
The North ◽  
Comprehensive Development ◽  
The Baltic ◽  
Inland Water Bodies ◽  
The Impact ◽  
Feed Coefficient

During the last 20 years there has been an interesting development of the Nordic fish farming, with regard to the feeding and farming technology and to the increase in production quantities. During the period 1974-1994 the production increased from 15,800 to about 250,000 tonnes/year. In 1974 the major part of the production was in Denmark, and in 1994 the major part was in Norway. The nutrient impact of fish farming on surrounding sea areas is mainly a function of the feed coefficient, the feed composition and metabolic processes in the fish. The comprehensive development of the feed composition and the feeding technology has resulted in reduced load of unmetabolized nutrients from fish farms, calculated per tonne fish produced. In 1974 the mean Nordic feed coefficient was 2.08 and in 1994 the coefficient was 1.25. Feed coefficients of 1.0-1.1 are now reported for Danish and Norwegian freshwater and marine fish farms. The nitrogen (N) and phosphorus (P) content of the feed has decreased, in addition the quality of the nutrient substances in the feed has changed, especially for N. The N content has decreased from 7.8 to 6.8% during the period 1974-1994 and the content of P has decreased from 1.7 to 0.7% during the same period. This development of the feed coefficient and the feed composition has resulted in a present load from a typical Nordic fish farm of 55 kg N and 4.8 kg P/t fish produced. The figures for 1974 were 132 kg N and 31 kg P/t fish produced. The Nordic fish farming production in 1994 resulted in a load of about 13,750 t N and about 1,200 t P on the actual recipients. The load from the Swedish, Finnish and Danish fish farming operations, with the Baltic Sea and the Skagerrak as the recipients, is negligible in comparison with other pollution sources. The quantities of N and P from the fish farming are equal to 0.5% of the atmospheric deposition on the sea surface and 3% of the atmospheric P load. Norwegian, Icelandic and the Faroe Islands fish farming operations are using the North Sea and the Norwegian Sea as the recipients. However, the nutrient load from single fish farms in certain coastal and inland water bodies can be significant and must be considered in the impact assessment together with other sources.

Effect of nickel(II) on the biomass yield of the activated sludge

1996 ◽  
Vol 34 (5-6) ◽  
pp. 163-171 ◽  
Author(s):  
Celal F. Gökçay ◽  
Ulku Yetis
Keyword(s):  
Activated Sludge ◽  
Decay Constant ◽  
Biomass Yield ◽  
Culture Conditions ◽  
Synthetic Wastewater ◽  
Base Line ◽  
Microbial Culture ◽  
Feed Composition ◽  
Steady State Condition ◽  
Applied Microbiology

Biomass yield of microorganisms is important in applied microbiology since it is the ultimate factor determining the amount of product produced regardless of whether product is growth-linked or not. In the case of environmental microbiology the opposite is true and minimizing the biomass produced, or the sludge in the relevant jargon, often is the prime goal. In this paper, a unique means of manipulating the microbial biomass yield of a heterogeneous culture to fulfil either of the two goals is presented. 5.0 mgl−1 Ni(II) in the feed composition to a completely mixed, once- through, activated sludge was found to induce the observed biomass yield of the microbial culture developed from sewage. As compared with the base-line study without Ni(II), where the reactor received synthetic wastewater only, true biomass yield was found to have increased along with the increased decay constant with the net effect of lowering observed biomass yield drastically at lower dilution rates and increasing it over that observed in the base-line study at higher dilution rates. At 10.0 mgl−1 influent Ni(II) concentration the culture conditions almost reverted back to the base- line study and at 25 mgl−1 Ni(II) concentration a truly steady-state condition could not be attained.

scholarly journals Adsorption for efficient low carbon hydrogen production: part 2—Cyclic experiments and model predictions

Adsorption ◽  
2021 ◽  
Author(s):  
Anne Streb ◽  
Marco Mazzotti
Keyword(s):  
Hydrogen Production ◽  
Carbon Capture And Storage ◽  
Clean Energy ◽  
Separation Performance ◽  
Low Carbon ◽  
Solution Theory ◽  
Feed Composition ◽  
Ideal Adsorbed Solution Theory ◽  
Adsorbed Solution ◽  
Adsorbed Solution Theory

Abstract Hydrogen as clean energy carrier is expected to play a key role in future low-carbon energy systems. In this paper, we demonstrate a new technology for coupling fossil-fuel based hydrogen production with carbon capture and storage (CCS): the integration of CO2 capture and H2 purification in a single vacuum pressure swing adsorption (VPSA) cycle. An eight step VPSA cycle is tested in a two-column lab-pilot for a ternary CO2–H2–CH4 stream representative of shifted steam methane reformer (SMR) syngas, while using commercial zeolite 13X as adsorbent. The cycle can co-purify CO2 and H2, thus reaching H2 purities up to 99.96%, CO2 purities up to 98.9%, CO2 recoveries up to 94.3% and H2 recoveries up to 81%. The key decision variables for adjusting the separation performance to reach the required targets are the heavy purge (HP) duration, the feed duration, the evacuation pressure and the flow rate of the light purge (LP). In contrast to that, the separation performance is rather insensitive towards small changes in feed composition and in HP inlet composition. Comparing the experimental results with simulation results shows that the model for describing multi-component adsorption is critical in determining the predictive capabilities of the column model. Here, the real adsorbed solution theory (RAST) is necessary to describe all experiments well, whereas neither extended isotherms nor the ideal adsorbed solution theory (IAST) can reproduce all effects observed experimentally.

30 The Effect of Creep Feed Composition and Form on Pre- and Post-weaning Growth Performance of Pigs and the Utilization of Low-quality Nursery Diets

2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 21-22
Author(s):  
Brenda Christensen ◽  
Lee-Anne Huber
Keyword(s):  
Growth Performance ◽  
Milk Replacer ◽  
Creep Feeding ◽  
Feed Composition ◽  
Creep Feed ◽  
Three Phase ◽  
Feeding Program ◽  
Main Protein ◽  
Liquid Milk ◽  
Feeding Regimen

Abstract Fifty-six litters standardized to 12 piglets from first-parity sows were used to determine the effects of creep and nursery diet compositions on pre- and post-weaning pig growth performance. At three days of age, litters (initial BW 2.31±0.61kg) were assigned to one of four creep feeding regimens (n=14): [1] commercial creep feed (COM), [2] liquid milk replacer (LMR), [3] pelleted milk replacer (PMR), or [4] no creep feed (NO); creep feeds contained 1.0% brilliant blue as a fecal marker. Fecal swabs were collected every 3±1 days to identify piglets that regularly consumed creep feed. At weaning (18±1 days of age), six pigs per litter that consumed creep feed were placed on either a HIGH- (contained highly digestible animal proteins) or LOW- (contained corn and soybean meal as the main protein sources) quality nursery diet (n = 7) in a three-phase feeding program over 38 days. The LMR disappeared at the greatest rate (37.7 g/pig/d; DM-basis) versus COM and PMR (10.8±1.5 g/pig/d; P < 0.001). Litters that received LMR had the greatest proportion of pigs with blue fecal swabs between study days 4 and 15 (85.0 vs 59.0±0.4%; P < 0.05) and LMR piglets had greater BW at weaning versus all other treatments (6.32, 6.02, 5.92, 5.67±0.14 kg, for LMR, COM, NO, and PMR, respectively; P < 0.001). Over the entire nursery period, pigs that received LOW diets had reduced ADG (399 vs 485±42 g; P < 0.001), ADFI (520 vs 595±37 g; P< 0.001), G:F (0.77 vs 0.82±0.03; P < 0.01), and BW at the end of the nursery period (21.2 vs 24.4±1.6 kg; P < 0.001), with no carryover effects of creep feeding regimen. Providing supplemental nutrition during the suckling period via LMR improved pig body weight at weaning, but did not improve post-weaning growth performance, regardless of nursery diet quality.

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