Spray-Dry Desulfurization of Flue Gas from Heavy Oil Combustion

Abstract

An experimental investigation on sulfur dioxide removal in a pilot-scale spray dryer from the flue gas generated by combustion of low-sulfur (S) heavy oil is reported. A limewater slurry was sprayed through an ultrasonic two-fluid atomizer in the spray-dry chamber, and the spent sorbent was collected downstream in a pulse-jet baghouse together with fly ash. Flue gas was sampled at different points to measure the desulfurization efficiency after both the spray-dry chamber and the baghouse. Parametric tests were performed to study the effect of the following variables: gas inlet temperature, difference between gas outlet temperature and adiabatic saturation temperature, lime-to-S ratio, and average size of lime particles in the slurry.Results indicated that spray drying is an effective technology for the desulfurization of low-S fuel oil flue gas, provided operating conditions are chosen carefully.In particular, the lowest gas inlet and outlet temperatures compatible with baghouse operation should be selected, as should a sufficiently high lime-to-S ratio. The attainment of a small lime particle size in the slurry is critical for obtaining a high desulfurization efficiency.A previously presented spray-dry flue gas desulfurization model was used to simulate the pilot-scale desulfurization tests, to check the ability of the model to predict the S capture data and its usefulness as a design tool, minimizing the need for pilot-scale experimentation.Comparison between model and experimental results was fairly good for the whole range of calcium/S ratios considered.

An experimental investigation on seawater SO2 scrubbing for marine application

“…Specific requirements for maritime SO 2 scrubbing systems include low energy consumption and pressure drop, simplicity and adaptability to existing equipment, and stability and easiness of control. One possible candidate technology meeting these requirements is spray scrubbing, which is known to be an effective technology for the desulfurization of fuel oil flue gas . The feasibility of this technology for marine application has to be studied, especially as regard the required seawater supply rate necessary to obtain reasonable desulfurization efficiencies.…”

Assessing the Environmental Impacts of Flow and Batch Syntheses of Hypercrosslinked Polymers for Low-Pressure Co2 Adsorption

“…Suggestions for future investigations, two major key factor should be considered. The CO 2 /H 2 O selectivity of HCPs warrants attention, especially considering that that flue gas often comprises a similar weight percentage of H 2 O steam as CO 2 [36,37], potentially leading to competition for adsorption sites. Competitive sorption between CO 2 and water has been observed in conditions, leading to lower CO 2 adsorption capacities in HCPs similar to the ones studies here [38].…”

Comparative Study of Sorbents for Spray Dry Scrubbing of SO2 from Flue Gases

“…Generally, the results showed improved SO 2 removal efficiencies at high stoichiometric molar ratios for all sorbents, which is in agreement with observations made by others. 20,21,23 There was a steady monotonic increase in the removal efficiency when the stoichiometric molar ratio was increased. Trona had a high SO 2 removal efficiency (98%) at SR = 2.0 compared to hydrated lime (82%) at SR = 2.0 and limestone (59%) at SR = 1.75.…”

“…The ranges of the operating parameters are presented in Table . The stoichiometric molar ratios of the three sorbents, ranging from 1 to 2.5 (based on prescribed ranges published in other works), − was controlled by varying the feed slurry concentration (6–12%) while keeping a constant gas phase SO 2 concentration of 1000 ppm and inlet gas phase temperature of 140 °C, typical of industrial untreated flue gas streams.…”