Effect of Particle Shape on the Reverse Combustion Process of a Packed Bed

Porous media (PM) has interesting advantages in compared with free flame combustion due to the higher burning rates, the increased power range, the extension of the lean flammability limits, and the low emissions of pollutants. Future clean internal combustion (IC) engines should have had minimum emissions level (for both gaseous and particulate matter) under possible lowest fuel consumption permitted in a wide range of speed, loads and having good transient response. These parameters strongly depend on mixture formation and combustion processes which are difficult to be controlled in a conventional engine. This may be achieved by realization of homogeneous combustion process in engine. This paper deals with the simulation of direct injection IC engine equipped with a chemically inert PM, with cylindrical geometry to homogenize and stabilize the combustion of engine. A 3D numerical model for PM engine is presented in this study based on a modified version of the KIVA-3V code. Due to lack of any published data for PM engines, numerical results of thermal and combustion wave propagation in a porous medium are compared with experimental data of lean methane-air mixture under filtration in packed bed and very good agreement is seen. For PM engine simulation methane as a fuel is injected directly inside hot PM that is assumed, mounted in cylinder head. Lean mixture is formed and volumetric combustion occurs in PM and in-cylinder. Mixture formation, pressure and temperature distribution in both phases of PM and in-cylinder fluid with the production of pollutants CO and NO and also effects of injection time in the closed part of the cycle are studied.

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Capturing CO2 from Biogas by MEA (Monoethanolamine) using Packed Bed Scrubber

Jurnal Teknik Kimia dan Lingkungan ◽

10.33795/jtkl.v4i2.157 ◽

2020 ◽

Vol 4 (2) ◽

pp. 105

Author(s):

Iqbal Nur Daiyan ◽

Leila Kalsum ◽

Yohandri Bow

Keyword(s):

Flow Rate ◽

Combustion Process ◽

Packed Bed ◽

Co2 Absorption ◽

Absorption Column ◽

Fossil Energy ◽

Spray Tower ◽

Biogas Purification ◽

Carbon Dioxide Co2 ◽

Reduction Of Co2

Biogas adalah salah satu sumber energi terbarukan yang dapat dimanfaatkan sebagai pengganti energi fosil. Biogas sebagian besar mengandung metan (CH4) dan karbon dioksida (CO2). Kandungan CO2 pada biogas mengurangi efisiensi pada proses pembakaran dan dapat menyebabkan korosi pada komponen-komponen logam yang kontak langsung dengan biogas. Pemurnian biogas dengan absorpsi merupakan suatu cara untuk menurunkan kadar CO2 yang terkandung, dan meningkatkan kandungan CH4 pada biogas sehingga biogas yang dihasilkan dapat digunakan sebagai bahan bakar. Penelitian ini ditujukkan untuk mempelajari pengaruh konsentrasi monoethanolamine (MEA) dan laju alir absorben terhadap penurunan kadar CO2 yang terkandung dalam biogas. Proses absorpsi CO2 dilakukan pada scrubber tipe spray tower, scrubber yang digunakan pada penelitian ini berbahan akrilik dengan diameter 64 mm, panjang scrubber 750 mm, tinggi packing pada scrubber 500 mm dan dengan kapasitas 1.5 m3. Laju alir biogas yang digunakan 26 L/menit dengan variasi laju alir larutan MEA sebesar 0,5, 1 dan 1,5 L/menit dan variasi konsentrasi larutan MEA sebesar 1, 3, 5, dan 7M. Hasil penelitian menunjukkan pada laju alir larutan MEA 1,5 L/menit dengan konsentrasi larutan MEA 7M dapat menurunkan CO2 dari 8,53% menjadi 0,10%, dan dapat meningkatkan kandungan metana (CH4) dari 69,24% menjadi 81,20%.Biogas is a renewable energy source that can be used as a substitute for fossil energy. Biogas mostly contains methane (CH4) and carbon dioxide (CO2). The content CO2 in biogas reduces the efficiency of the combustion process and cause corrosion in metal components when direct contact with biogas. Biogas purification using absorption method can reduce levels of CO2 contained and increase levels of CH4 then the biogas produced can be used as fuel. This research study the effect of monoethanolamine (MEA) concentration and absorbent flow rate on the reduction of CO2 contained in biogas. CO2 absorption process is carried out by a spray tower type scrubber. It consisted of an acrylic absorption column (64 mm in diameter, 750 mm in height, 500 mm in packing height and 1.5 m3 in capacity). Biogas flow rate used is 26 L/min with variation of the flow rate of MEA 0.5, 1, and 1,5 L/min and concentration of MEA solution 1, 3, 5, and 7M. The results showed that the flow rate of MEA 1.5 L/min with a concentration of 7M MEA solution can reduce CO2 from 8.53% to 0.10% and can increase the methane (CH4) load from 69.24% to 81.20%.

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Packed bed pressure drop dependence on particle shape, size distribution, packing arrangement and roughness

Powder Technology ◽

10.1016/j.powtec.2013.06.022 ◽

2013 ◽

Vol 246 ◽

pp. 590-600 ◽

Cited By ~ 94

Author(s):

K.G. Allen ◽

T.W. von Backström ◽

D.G. Kröger

Keyword(s):

Pressure Drop ◽

Size Distribution ◽

Particle Shape ◽

Packed Bed ◽

Packing Arrangement

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Combustion Modelling of a 20 kW Pellet Boiler

Volume 6B: Energy ◽

10.1115/imece2018-88063 ◽

2018 ◽

Cited By ~ 1

Author(s):

João Silva ◽

Lelis Fraga ◽

Manuel Eduardo Ferreira ◽

Sergio Chapela ◽

Jacobo Porteiro ◽

...

Keyword(s):

Cfd Simulation ◽

Combustion Process ◽

Packed Bed ◽

Pollutant Emissions ◽

Cfd Modeling ◽

Ansys Fluent ◽

Fully Integrated ◽

Complex Process ◽

Combustion Modelling ◽

Physical And Chemical

In a domestic boiler that uses pellets as fuel, it is important to control the efficiency of the combustion process. The combustion process in the boiler is a complex process that involves several and simultaneous phenomena such as fluid flow, physical and chemical reactions and heat and mass transfer. Computational Fluid Dynamics (CFD) modeling in combination with detailed sub-models for the solid fuel conversion is a useful tool to study the combustion performance and to study, for instance, the pollutant emissions. This paper presents the CFD simulation of the combustion in a 20 kW pellet boiler using the ANSYS Fluent software with a fully integrated packed-bed model. Furthermore, an experimental test was performed to contrast the results obtained. The CFD results were able to predict the arrangement of the particles on the grate, temperature profile of the particles and, the main gas species concentration inside of the boiler with reasonable accuracy when compared with the experimental measurements.

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