Achieving an ultralow emission of nitrogen oxides by using activated carbon with hydrophobic modification

• Selective noncatalytic reduction (SNCR) systems have been widely used for denitrification in small capacity boilers, such as biomass- and waste-fueled boilers. However, these systems cannot meet the requirements of ultralow emission regulations, i.e., 50 mg m−3. This work proposes a new solution that combines SNCR and activated carbon (AC). To solve the problem caused by the wettability of AC, which can significantly reduce the quantity of NOx that can be adsorbed and block active cites, hydrophobic modification was employed to amend the properties of AC. The influences of the key operating parameters on the denitrification of AC, including the reaction temperature, O2 concentration, feed gas flow rate, and contents of SO2 and CO2, have been investigated experimentally. A novel solution that combines AC and SNCR was proposed for industrial applications, and the economic feasibility has been verified. The results have demonstrated that this hybrid solution can achieve a low levelized cost of denitrification, which is 59.8% and 33.7% lower than those of SCR and hybrid SNCR/SCR.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Energiteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Energy Engineering (hsv//eng)

Keyword

Activated carbon

Denitrification

Economic feasibility

Hydrophobic modification

Molecular dynamics simulation

Ultralow emission

Boilers

Flow of gases

Molecular dynamics

Nitrogen oxides

Reaction kinetics

% reductions

Dynamics simulation

Economic feasibilities

Emissions regulations

New solutions

Non-catalytic

Reduction systems

Small capacity boiler

Ultralow emissions

Hydrophobicity

Publication and Content Type

ref (subject category)

art (subject category)