A Medium-Scale 50 MWfuel Biomass Gasification Based Bio-SNG Plant: A Developed Gas Cleaning Process

Abstract

Natural gas is becoming increasingly important as a primary energy source. A suitable replacement for fossil natural gas is bio-SNG, produced by biomass gasification, followed by methanation. A major challenge is efficient gas cleaning processes for removal of sulfur compounds and other impurities. The present study focuses on development of a gas cleaning step for a product gas produced in a 50 MWfuel gasification system. The developed gas cleaning washing process is basically a modification of the Rectisol process. Several different process configurations were evaluated using Aspen plus, including PC-SAFT for the thermodynamic modeling. The developed configuration takes advantage of only one methanol wash column, compared to two columns in a conventional Rectisol process. Results from modeling show the ability of the proposed configuration to remove impurities to a sufficiently low concentrations -almost zero concentration for H2S, CS2, HCl, NH3 and HCN, and approximately 0.01 mg/Nm 3 for COS. These levels are acceptable for further upgrading of the gas in a methanation process. Simultaneously, up to 92% of the original CO2 is preserved in the final cleaned syngas stream. No process integration or economic consideration was performed within the scope of the present study, but will be investigated in future projects to improve the overall process.

Experimental Study on Spray Breakup in Turbulent Atomization Using a Spiral Nozzle

“…Note that t sh0 is the first term in Equation (6). The average sheet velocity at the edge of the helix can be calculated as [74]:…”

“…The upper arm (5) was moved using a step motor in the direction of X-axis ( Figure 5). This system was placed on the top of a bottom moving arm (6), which was moving in the direction of Y-axis ( Figure 5). The area under the nozzle (4) was scanned in a length of 300 mm in the X-direction and 600 mm in the Y-direction, which was the maximum possible range of the experimental device used.…”

“…Gas scrubbers are rather complicated devices, in which the polluted air is cleaned using a sprayed liquid, mostly various aqueous solutions depending on the gas to be removed. This includes, for example, CO 2 and VOC removal [1][2][3], flue gas desulphurization [4][5][6], and ammonia separation [7]. Last but not least, scrubbing systems have widely been recognized in separation of particulate matter [8][9][10][11][12], the release of which is due mostly to various combustion processes [13][14][15] and, for example, comminution technologies [16,17].…”

“…Experimental setup for the impact measurement: Bed plate (1), metal casing (2), impact surface (3), spiral nozzle (4), upper movable arm(5), lower movable arm(6).…”

“…A scheme of the experimental setup for the assessment of the spray morphology/kinetics with the Canon D70 camera (1), Nd:YAG pulse laser (2), spiral nozzle (3), centrifugal pump (4), flowmeter (5), manometer(6), and valve(7).…”