Numerical evaluation of minimum residence time in a delay chamber using scale-down model

It is discussed the using of dynamic programming method to optimize the parameters of the cascade of ideal mixing reactors, which is held isothermal first order reaction. It is found, that the minimum volume of the cascade of reactors corresponds to the minimum residence time of substance in this cascade. The optimum value of residence time for all reactors are equal and all ratio of input and output concentrations are equal, hence, and all volumes of reactors are also equal. A total volume of the cascade of reactors is less than the amount single. Application of the method of dynamic programming is illustrated with an example of the calculation of the polymerization in a cascade of four reactors according to the literature experimental data.

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History of the endangered thread-leaved sundew (Drosera filiformis) in southern Nova Scotia

Canadian Journal of Botany ◽

10.1139/b04-137 ◽

2005 ◽

Vol 83 (1) ◽

pp. 14-21 ◽

Cited By ~ 1

Author(s):

Mark Landry ◽

Les C Cwynar

Keyword(s):

Nova Scotia ◽

Residence Time ◽

Radiocarbon Dating ◽

Plant Macrofossil ◽

Radiocarbon Age ◽

Macrofossil Analysis ◽

The Past ◽

History Of ◽

Minimum Residence Time ◽

Plant Macrofossil Analysis

We used the techniques of plant macrofossil analysis and radiocarbon dating to determine the minimum residence time of the endangered thread-leaved sundew (Drosera filiformis Raf.) in three bogs of southern Nova Scotia. The minimum residence times are 4240 cal. year BP for Swain's Road Bog, 2050 cal. year BP for Villagedale Bog, and very recent (modern radiocarbon age) for Port La Tour Bog, indicating that the species has likely been in the region for the past 4240 years. Analysis of nearby Old School Road Bog, which lacks D. filiformis today, failed to find any evidence that it formerly occurred there, suggesting that it may not have been more widespread in the past than it is today.Key words: Drosera filiformis, thread-leaved sundew, plant macrofossil analysis, radiocarbon dating, bogs, minimum residence time.

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Experimental Study on Rich Oxygen Gasification and Ash Character in Entrainedflow Coal Gasifier

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.860-863.1405 ◽

2013 ◽

Vol 860-863 ◽

pp. 1405-1411

Author(s):

Bai Qian Dai ◽

Xiao Jiang Wu ◽

Tong Lou ◽

Zhong Xiao Zhang

Keyword(s):

Residence Time ◽

Feeding Rate ◽

Carbon Conversion ◽

Gas Concentration ◽

Cold Gas Efficiency ◽

Coal Gasifier ◽

Scale Down ◽

Gas Efficiency ◽

Increasing Temperature ◽

Cold Gas

Entrainedflow Gasifier with Large Capacity and Slagging Tap is Usually Use for IGCC and Largescale Chemical Industrial Factory. while, there are 57% of Reserved Coal is Highfusion Temperature Coal, which Cannot Satisfy the Requirement of Thegasification for Slagging Tap. . Therefore, Two Typical Kinds of Chinese Coals Wereselected and Gasified in a Lab-Scale down-Flow Gasifier with Feeding Rate Ataround 1kg/h. the Results Show that along with the Increasing Temperature, Thecarbon Conversion and Cold Gas Efficiency will be Increased Quickly Whentemperature is below 1400°C, and then Increased Slowly when above 1400°C. the Optimum O/C Molarratio is around 1:1, the Cold Gas Efficiency and Carbon Conversion under Thisexperimental Condition (1300-1400°C) are Separately 31% and 80%. at the Optimumgasification Condition, Increasing the Residence Time will also Increase Thecoal Gas Concentration, Carbon Conversion and Cold Gas Efficiency. under Thisexperimental Condition, the Best Residence Time is at Least 1.5~2.0s.

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Minimum residence time, biogeographical origin, and life cycle as determinants of the geographical extent of naturalized plants in continental Chile

Diversity and Distributions ◽

10.1111/j.1366-9516.2005.00145.x ◽

2005 ◽

Vol 11 (3) ◽

pp. 183-191 ◽

Cited By ~ 77

Author(s):

Sergio A. Castro ◽

Javier A. Figueroa ◽

Mélica Muñoz-Schick ◽

Fabian M. Jaksic

Keyword(s):

Life Cycle ◽

Residence Time ◽

Naturalized Plants ◽

Minimum Residence Time

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Drying Machines with Combined Hydrodynamic Regimes

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1199/1/012093 ◽

2021 ◽

Vol 1199 (1) ◽

pp. 012093

Author(s):

N Artyukhova ◽

J Krmela ◽

V Krmelová ◽

A Artyukhov

Keyword(s):

Engineering Design ◽

Cross Section ◽

Residence Time ◽

Working Space ◽

Optimization Calculation ◽

Polydisperse Material ◽

Factors Of Influence ◽

Minimum Residence Time ◽

Dispersed Material ◽

Free Area

Abstract The article is devoted to the study of multistage dryers with vertical sectioning of the working space. The factors of influence of the design of the shelf contact and the consumption of the drying agent on the mode of movement of monodisperse and polydisperse material are analyzed. The achievement of the required hydrodynamic regime (at a constant consumption of the drying agent) was ensured by changing the length of the shelf contact, the angle of its inclination to the horizon, and the degree of perforation (free area of cross-section). The features of changing the mode of granular material movement at various stages of the gravitational shelf dryer are shown. A technique for the optimization calculation of a gravitational shelf dryer is proposed. As an objective function, the minimum residence time of the dispersed material in the dryer is taken, at which the required amount of moisture is removed. Variants of the designs of the stages of a gravitational shelf dryer are shown and the features of the movement of dispersed material on the steps are described. The results obtained can be used as the basis for the engineering design of gravitational shelf dryers.

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