IMPROVEMENT OF BIOGAS UPGRADING PROCESS USING CHEMICAL ABSORPTION AT AMBIENT CONDITIONS

Biogas major components are methane, carbon dioxide and traces of hydrogen sulfide, ammonia and nitrogen. Biogas upgrading process is the process by which carbon dioxide (composing 40 % of the biogas) is removed. In this study chemical absorption process using three different solvents (10 – 30 % monoethanolamine, 4 – 12 % sodium hydroxide and 5 – 15 % aqueous ammonia) was performed to produce methane-enriched biogas. A laboratory-scale packed-column apparatus containing efficient and cheap packing material (plastic bioball) was used to perform the experimental work in this study. Initial absorption runs were performed to select the best solvent type and concentration. Monoethanolamine (MEA) was proven to have the highest ability in producing upgraded biogas using a single absorption column apparatus at ambient conditions. The liquid to gas flow ratio was investigated using 30 % MEA solution. Optimum liquid to gas flow ratio for biogas upgrading process was determined to be about 18 (on mass basis). Biogas with methane content up to 96.1 v/v% was produced with CO2 loading capacity up to 0.24 mole-CO2 per mole-MEA.

Download Full-text

Mass Transfer Enhancement for CO2 Absorption in Structured Packed Absorption Column

Journal of the chemical society of pakistan ◽

10.52568/000803/jcsp/41.05.2019 ◽

2019 ◽

Vol 41 (5) ◽

pp. 820-820

Author(s):

Pongayi Ponnusamy Selvi and Rajoo Baskar Pongayi Ponnusamy Selvi and Rajoo Baskar

Keyword(s):

Mass Transfer ◽

Transfer Coefficient ◽

Mass Transfer Coefficient ◽

Gas Flow ◽

Aqueous Ammonia ◽

Volume Flow Rate ◽

Packed Column ◽

Operating Conditions ◽

Co2 Absorption ◽

Absorption Column

The acidic gas, Carbon dioxide (CO2) absorption in aqueous ammonia solvent was carried as an example for industrial gaseous treatment. The packed column was provided with a novel structured BX-DX packing material. The overall mass transfer coefficient was calculated from the absorption efficiency of the various runs. Due to the high solubility of CO2, mass transfer was shown to be mainly controlled by gas side transfer rates. The effects of different operating parameters on KGav including CO2 partial pressure, total gas flow rates, volume flow rate of aqueous ammonia solution, aqueous ammonia concentration, and reaction temperature were investigated. For a particular system and operating conditions structured packing provides higher mass transfer coefficient than that of commercial random packing.

Download Full-text

Effects of O[sub 2] gas flow ratio and flow rate on the formation of RuO[sub 2] thin films by reactive sputtering

Journal of Vacuum Science & Technology B Microelectronics Processing and Phenomena ◽

10.1116/1.591385 ◽

2000 ◽

Vol 18 (3) ◽

pp. 1348 ◽

Cited By ~ 8

Author(s):

Y. Abe ◽

Y. Kaga ◽

M. Kawamura ◽

K. Sasaki

Keyword(s):

Thin Films ◽

Flow Rate ◽

Gas Flow ◽

Reactive Sputtering ◽

Flow Ratio ◽

Gas Flow Ratio

Download Full-text

A Comparative Study of Nitrogen Gas Flow Ratio Dependence on the Electrical Characteristics of Sputtered Titanium Nitride Gate Bulk Planar Metal–Oxide–Semiconductor Field-Effect Transistors and Fin-Type Metal–Oxide–Semiconductor Field-Effect Transistors

Japanese Journal of Applied Physics ◽

10.1143/jjap.48.05dc01 ◽

2009 ◽

Vol 48 (5) ◽

pp. 05DC01 ◽

Cited By ~ 20

Author(s):

Tetsuro Hayashida ◽

Yongxun Liu ◽

Takashi Matsukawa ◽

Kazuhiko Endo ◽

Shinich O'uchi ◽

...

Keyword(s):

Metal Oxide ◽

Field Effect ◽

Gas Flow ◽

Field Effect Transistors ◽

Metal Oxide Semiconductor ◽

Oxide Semiconductor ◽

Electrical Characteristics ◽

Flow Ratio ◽

Nitrogen Gas ◽

Gas Flow Ratio

Download Full-text

Dependence of Electrical and Optical Properties of the Al Doped ZnO for Transparent Conductors Deposited by rf–Magnetron Sputtering on the O2/Ar Gas Flow Ratio

Key Engineering Materials - High-Performance Ceramics IV ◽

10.4028/0-87849-410-3.564 ◽

2007 ◽

pp. 564-566

Author(s):

Chong Mu Lee ◽

Keun Bin Yim ◽

Choong Mo Kim

Keyword(s):

Optical Properties ◽

Magnetron Sputtering ◽

Gas Flow ◽

Rf Magnetron Sputtering ◽

Transparent Conductors ◽

Flow Ratio ◽

Electrical And Optical Properties ◽

Gas Flow Ratio ◽

Doped Zno ◽

Ar Gas

Download Full-text

Effect of gas flow ratio in PE-CVD on elastic properties of sub-micron thick silicon nitride films for MEMS

The 13th International Conference on Solid-State Sensors, Actuators and Microsystems, 2005. Digest of Technical Papers. TRANSDUCERS '05. ◽

10.1109/sensor.2005.1496550 ◽

2005 ◽

Author(s):

Y. Isono ◽

T. Namazu ◽

Y. Saito ◽

A. Yamaguchi ◽

N. Fukushima

Keyword(s):

Silicon Nitride ◽

Elastic Properties ◽

Gas Flow ◽

Flow Ratio ◽

Silicon Nitride Films ◽

Gas Flow Ratio

Download Full-text

Effect of Differentiated Injection Ratio, Gas Flow Rate, and Slag Thickness on Mixing Time and Open Eye Area in Gas-Stirred Ladle Assisted by Physical Modeling

Metals ◽

10.3390/met9050555 ◽

2019 ◽

Vol 9 (5) ◽

pp. 555 ◽

Cited By ~ 5

Author(s):

Luis E. Jardón-Pérez ◽

Daniel R. González-Morales ◽

Gerardo Trápaga ◽

Carlos González-Rivera ◽

Marco A. Ramírez-Argáez

Keyword(s):

Flow Rate ◽

Gas Flow ◽

Mixing Time ◽

Flow Ratio ◽

Gas Flow Rate ◽

Nsga Ii ◽

Image Velocimetry ◽

Gas Flow Ratio ◽

Slag Thickness ◽

Injection Ratio

In this work, the effects of equal (50%/50%) or differentiated (75%/25%) gas flow ratio, gas flow rate, and slag thickness on mixing time and open eye area were studied in a physical model of a gas stirred ladle with dual plugs separated by an angle of 180°. The effect of the variables under study was determined using a two-level factorial design. Particle image velocimetry (PIV) was used to establish, through the analysis of the flow patterns and turbulence kinetic energy contours, the effect of the studied variables on the hydrodynamics of the system. Results revealed that differentiated injection ratio significantly changes the flow structure and greatly influences the behavior of the system regarding mixing time and open eye area. The Pareto front of the optimized results on both mixing time and open eye area was obtained through a multi-objective optimization using a genetic algorithm (NSGA-II). The results are conclusive in that the ladle must be operated using differentiated flow ratio for optimal performance.

Download Full-text

EFFECTS OF HYDROGEN GAS FLOW RATIO ON THE QUALITY OF NANO-DIAMOND FILMS

International Journal of Modern Physics B ◽

10.1142/s0217979202010543 ◽

2002 ◽

Vol 16 (06n07) ◽

pp. 876-880

Author(s):

S. G. Wang ◽

Q. Zhang ◽

D. J. Yang ◽

S. F. Yoon ◽

J. Ahn ◽

...

Keyword(s):

Grain Size ◽

Gas Flow ◽

Microwave Plasma ◽

Diamond Films ◽

Gaseous Mixture ◽

Hydrogen Gas ◽

Chemical Vapor Deposition Method ◽

Flow Ratio ◽

Gas Flow Ratio

In this paper, we studied the effects of hydrogen gas flow ratio of [H2]/[N2 + CH4 + H2] on the quality of nanometer diamond (nano-diamond) films prepared by microwave plasma enhanced chemical vapor deposition method. Nano-diamond films were deposited on the silicon substrates from a gaseous mixture of nitrogen, methane and hydrogen. The experimental results show that if only using a gaseous mixture of nitrogen and methane, although we can obtain nano-diamond films with a grain size of about 5nm, the diamond films contain much non-diamond components. With hydrogen addition, and with increasing the hydrogen gas flow ratio from 1 to 10%, the non-diamond components in the films are significantly reduced and the grain size of the films increases from 5nm to 60nm. However optical transmittance of the films increases with increasing hydrogen gas flow ratio from 1 to 7% because of an improvement of film quality, and then decreases with further increasing hydrogen gas flow ratio owing to the increase of film roughness.

Download Full-text