The influence of inlet diameter and average hole diameter of one side liquid distributor on the performance of liquid distribution

2021 ◽  
Author(s):  
Xingyang Yuan ◽  
Wei Zhao ◽  
Feilong Zhan ◽  
Hua Zhang ◽  
Tao Ren
Keyword(s):  
Hole Diameter ◽  
Liquid Distribution ◽  
Liquid Distributor

Experimental Investigation on the Liquid Distributor Performance for the Falling Film Evaporation Process

2014 ◽  
Vol 1015 ◽  
pp. 696-699
Author(s):  
Dong Dong Feng ◽  
Feng Ming Zhang ◽  
Wei Yang ◽  
Yu Xu ◽  
Xiao Bin Pei ◽  
...  
Keyword(s):  
High Flow ◽  
Hole Diameter ◽  
Falling Film ◽  
Evaporation Process ◽  
Liquid Distribution ◽  
Film Evaporation ◽  
Liquid Height ◽  
Falling Film Evaporation ◽  
Liquid Distributor ◽  
The Relationship

In this paper, the liquid distributor performance for the falling film evaporation process was tested, and the relationship between the liquid height and flow rate were studied in the experiment. The results showed that the liquid height of liquid distributor is proportional to flow, liquid distributing hole diameter and flow, but inversely proportional to liquid distribution aperture. Overflow may be present at a high flow.

scholarly journals Liquid distribution and its effect on local mass transfer in a packed column of Pall rings

2021 ◽  
Author(s):  
Yongjia Zhu
Keyword(s):  
Mass Transfer ◽  
Gas Flow ◽  
Transfer Coefficients ◽  
Liquid Distribution ◽  
Fully Developed Flow ◽  
Flow Rates ◽  
Local Mass ◽  
Local Mass Transfer ◽  
Liquid Distributor ◽  
Wall Flow

The spatial variations of liquid distribution and local mass transfer coefficient in a 0.30-m column of 25.4-m Pall rings were investigated. The data of liquid distribution was collected with a 39-cell liquid collector and a wall-flow tube from a doubled-wall section in the column at the packing-support level. The local mass transfer coefficients were measured via the electrochemical technique by individual cathodic nickel-coated Pall rings placed at various spatial positions. Both measurements were conducted at various fluid flow rates with three liquid distributor designs at different bed heights. Liquid distribution and local mass transfer coefficients observed were far from uniform in the column. The wall flow developed along the packed bed until a fully developed flow pattern was reached. With more uniform initial liquid distribution, the less packing height needed to reach the fully developed flow pattern along with higher the mass transfer efficiency in the column. Ladder-type liquid distributor (LLD) showed less angular effect in measurements. Increasing the liquid flow rate slightly improved the uniformity of liquid distribution and enhanced the mass transfer. No influence of gas flow rate on liquid distribution and mass transfer coefficient was found at the range of gas flow rates used. These gas flow rates were much lower than the loading point. Liquid maldistribution factor and mass transfer maldistribution factor decreased with increases in the uniformity of the initial liquid distribution. These values were 0.21(0.48). 0.16(0.26) and 0.14(0.22) for single-point liquid distributor (SPLD), cross-type liquid distributor (CLD) and LLD, respectively. By comparison, a good agreement was observed on the relation of liquid maldistribution factor and mass transfer maldistribution factor.

scholarly journals Liquid distribution and its effect on local mass transfer in a packed column of Pall rings

2021 ◽  
Author(s):  
Yongjia Zhu
Keyword(s):  
Mass Transfer ◽  
Gas Flow ◽  
Transfer Coefficients ◽  
Liquid Distribution ◽  
Fully Developed Flow ◽  
Flow Rates ◽  
Local Mass ◽  
Local Mass Transfer ◽  
Liquid Distributor ◽  
Wall Flow

The spatial variations of liquid distribution and local mass transfer coefficient in a 0.30-m column of 25.4-m Pall rings were investigated. The data of liquid distribution was collected with a 39-cell liquid collector and a wall-flow tube from a doubled-wall section in the column at the packing-support level. The local mass transfer coefficients were measured via the electrochemical technique by individual cathodic nickel-coated Pall rings placed at various spatial positions. Both measurements were conducted at various fluid flow rates with three liquid distributor designs at different bed heights. Liquid distribution and local mass transfer coefficients observed were far from uniform in the column. The wall flow developed along the packed bed until a fully developed flow pattern was reached. With more uniform initial liquid distribution, the less packing height needed to reach the fully developed flow pattern along with higher the mass transfer efficiency in the column. Ladder-type liquid distributor (LLD) showed less angular effect in measurements. Increasing the liquid flow rate slightly improved the uniformity of liquid distribution and enhanced the mass transfer. No influence of gas flow rate on liquid distribution and mass transfer coefficient was found at the range of gas flow rates used. These gas flow rates were much lower than the loading point. Liquid maldistribution factor and mass transfer maldistribution factor decreased with increases in the uniformity of the initial liquid distribution. These values were 0.21(0.48). 0.16(0.26) and 0.14(0.22) for single-point liquid distributor (SPLD), cross-type liquid distributor (CLD) and LLD, respectively. By comparison, a good agreement was observed on the relation of liquid maldistribution factor and mass transfer maldistribution factor.

scholarly journals Liquid Distribution and its Effect on the Organic Removal in a Trickle Bed Bioreactor

2021 ◽  
Author(s):  
Maryam Jedari Eyvazi
Keyword(s):  
Cross Section ◽  
Flow Rate ◽  
Liquid Flow ◽  
Liquid Flow Rate ◽  
Removal Rate ◽  
Single Point ◽  
Liquid Distribution ◽  
Bed Height ◽  
Liquid Distributor ◽  
Bod Removal

Propylene glycol methyl ether was removed from wastewater in a trickling bed bioreactor under different liquid distribution conditions. A 0.3 m diameter column filled with two heights of 0.7 m and 1.4 m with 2 cm plastic spheres were used. The wastewater flow rate varied from 0.184 to .0918 kg/m₂.s. The effect of the initial liquid distribution was examined using two types of liquid distributors: a multipoint liquid distributor and a central single point liquid distributor. Over 96 hours of treatment period, the BOD₅ was reduced by 85% and 65% under the most uniform liquid distribution condition and the poor liquid distribution condition, respectively, achieved in this study. Increasing the liquid flow rate from 0.184 to 0.198 kg/m₂.s, it increased the dynamic liquid holdup by 53% and the apparent BOD₅ removal rate constant by 23% at 1.4 m bed height using the multipoint liquid distributor. Moreover, with the use of the multipoint liquid distributor, the apparent reaction when the liquid flow rate was increased from 0.184kg/m₂.s to 0.918 kg/m₂.s. In addition, it was found that the effect of an increase in the bed height on the percentage BOD₅ removal was not significant when initial liquid distribution was uniform. Under the uniform initial condition, only 4% increase in the percentage BOD₅ removal was observed when the bed height increased from 0.7 to 1.4 m whereas when the initial distribution was extremely non-uniform, the percentage of BOD₅ removal was increased by 20% with increasing bed height. The local distribution of the BOD₅ removal was not uniform across the bed cross-section and it was affected by the liquid flow distribution across the bed cross-section.

Experimental Study on the Liquid Distributor of Horizontal Tube Falling Film Evaporator

2012 ◽  
Vol 550-553 ◽  
pp. 2897-2902
Author(s):  
Bai Song Hu ◽  
Fan Zhang ◽  
Xin Liang Wang ◽  
Hui Peng Sun ◽  
Xiao Ping Shi
Keyword(s):  
Experimental Study ◽  
Horizontal Tube ◽  
Falling Film ◽  
Liquid Distribution ◽  
Film Evaporation ◽  
Film Evaporator ◽  
Guide Plate ◽  
Liquid Flux ◽  
Falling Film Evaporation ◽  
Liquid Distributor

A calandria liquid distributor device was designed for horizontal falling film evaporation. The guide plate was introduced in this, which is easy to manufacture and can effectively reduce splash phenomenon. This paper studies the liquid distribution from the relation between distributive unwell-distributed coefficient and liquid flux of distributor tube and distributor hole. The result showed that the distributive unwell-distributed coefficient of in liquid distributor was decreased along with accretion of liquid flux, as apposed to homogeneous perforated. The unwell-distributed hole coefficient of distributor tube No.0 was increased along with accretion of flux, as apposed to distributor tube No.1 and distributor tube No.2.

scholarly journals Bed structure and its impact on liquid distribution in a trickle bed reactor

2021 ◽  
Author(s):  
Akarsha Srivastava ◽  
Krishna Nigam ◽  
Shantanu Roy
Keyword(s):  
Gas Flow ◽  
Flow Characteristics ◽  
Two Phase ◽  
Liquid Distribution ◽  
Trickle Bed Reactor ◽  
Catalytic Sites ◽  
Void Structure ◽  
Liquid Distributor ◽  
Trickle Bed ◽  
Catalyst Pellets

The work reported in this investigation involves the determination of the hydrodynamic properties of the Trickle Bed Reactor which has been loaded in various ways to mark the effect of the loading methodologies employed to pack the catalyst pellets. The bed structure of a packed three-phase reactor is critical to study as it provides the essential contact between the phases and provides the catalytic sites where the reaction takes place. Depending on the structural properties of the bed such as local void structure, liquid distribution, two-phase pressure drop, and holdup of fluids gets affected. The study aims to envelop the catalyst bed characteristics such as the local void structure, the length of the catalyst bed, flow characteristics such as liquid and gas flow rate, and liquid distributor at the top of the catalyst bed to gauge and quantify their effect on the hydrodynamics of a trickle bed reactor.

scholarly journals Liquid Distribution and its Effect on the Organic Removal in a Trickle Bed Bioreactor

2021 ◽  
Author(s):  
Maryam Jedari Eyvazi
Keyword(s):  
Cross Section ◽  
Flow Rate ◽  
Liquid Flow ◽  
Liquid Flow Rate ◽  
Removal Rate ◽  
Single Point ◽  
Liquid Distribution ◽  
Bed Height ◽  
Liquid Distributor ◽  
Bod Removal

Propylene glycol methyl ether was removed from wastewater in a trickling bed bioreactor under different liquid distribution conditions. A 0.3 m diameter column filled with two heights of 0.7 m and 1.4 m with 2 cm plastic spheres were used. The wastewater flow rate varied from 0.184 to .0918 kg/m₂.s. The effect of the initial liquid distribution was examined using two types of liquid distributors: a multipoint liquid distributor and a central single point liquid distributor. Over 96 hours of treatment period, the BOD₅ was reduced by 85% and 65% under the most uniform liquid distribution condition and the poor liquid distribution condition, respectively, achieved in this study. Increasing the liquid flow rate from 0.184 to 0.198 kg/m₂.s, it increased the dynamic liquid holdup by 53% and the apparent BOD₅ removal rate constant by 23% at 1.4 m bed height using the multipoint liquid distributor. Moreover, with the use of the multipoint liquid distributor, the apparent reaction when the liquid flow rate was increased from 0.184kg/m₂.s to 0.918 kg/m₂.s. In addition, it was found that the effect of an increase in the bed height on the percentage BOD₅ removal was not significant when initial liquid distribution was uniform. Under the uniform initial condition, only 4% increase in the percentage BOD₅ removal was observed when the bed height increased from 0.7 to 1.4 m whereas when the initial distribution was extremely non-uniform, the percentage of BOD₅ removal was increased by 20% with increasing bed height. The local distribution of the BOD₅ removal was not uniform across the bed cross-section and it was affected by the liquid flow distribution across the bed cross-section.

PATTERNS OF GASTROPOD MOLLUSK PREDATION ON BIVALVE MOLLUSKS ALONG THE UPPER TEXAS GULF COAST

2018 ◽  
Vol 70 (1) ◽  
Author(s):  
Serena J. Randolph ◽  
Alan D. Maccarone
Keyword(s):  
Shell Thickness ◽  
Prey Species ◽  
Gulf Coast ◽  
Prey Selection ◽  
Drill Hole ◽  
The United States ◽  
Hole Diameter ◽  
Bivalve Mollusks ◽  
Collection Site ◽  
Drill Holes

Abstract Predation on bivalve mollusks by gastropod mollusks is common in coastal regions of the United States; however, few previous studies have examined whether drilling gastropods exhibit prey selection. In 2016, shells with small holes drilled by as many as two gastropod predators were collected at three sites separated by 30 km along the Texas Upper Gulf Coast on the Bolivar Peninsula (29° 40′N, 94° 90′W). The likeliest predators in these waters are the southern oyster drill (Stramonita haemastoma Linnaeus 1767) and the moon snail (Neverita duplicate Say 1822). Collected shells were identified to species and measurements were taken to examine statistical relationships between predators and prey species. These measurements included drill-hole diameter, shell thickness, drill-hole completeness, number of drill attempts, and collection site. Across the three locations, 17 different species of shells with drill holes were collected; of these, we focused on the ten most abundant species (n = 277 shells). The sample showed high variation in drill-hole diameter, shell thickness, and drill-hole completeness. Both the total number of holes and mean drill-hole diameter differed significantly among prey species (ANOVA, both P < 0.0001). In addition, drill-hole diameter correlated directly with prey shell thickness (P < 0.0001). Shells whose drill holes were complete were significantly thinner than shells with incomplete holes (P < 0.0001). Mean prey shell thickness, mean drill-hole diameter, and mean number of drill holes all differed significantly by collection site (all P < 0.0001). Ecological and morphological implications related to gastropod predation on mollusks are discussed.

Sign in / Sign up

Export Citation Format

Share Document