Continuous CO(2) capture and MSWI fly ash stabilization, utilizing novel dynamic equipment.

Novel dynamic equipment with gas in and out continuously was developed to study the capture capacity of CO(2). Municipal solid waste incineration (MSWI) fly ash has a high capture rate of CO(2) in CO(2)-rich gas. Fly ash can sequester pure CO(2) rapidly, and its capacity is 16.3 g CO(2)/100 g fly ash with no water added and 21.4 g CO(2)/100 g fly ash with 20% water added. For simulated incineration gas containing 12% CO(2), the capture rate decreased and the capacity was 13.2 g CO(2)/100 g fly ash with no water added and 18.5 g CO(2)/100 g fly ash with 20% water added. After accelerated carbonation, the C and O contents increased, indicating CO(2) capture in the fly ash; CO(2) combines with Ca(OH)(2) to form CaCO(3), which increased the CaCO(3) content from 12.5 to 54.3%. The leaching of Pb markedly decreased from 24.48 to 0.111 mg/L.

[Improvement of disintegration and anaerobic digestion for sewage sludge with ultrasonic generator].

Ultrasonic generating trough was applied to study the impact of ultrasonic on conditioning of sewage sludge. There are few ultrasonic generators for sludge treatment specifically, so we designed a double-frequency ultrasonic generating trough which could adjust frequency, energy density and treating time flexibly. In the research characteristics of sewage sludge treated by single-frequency and double-frequency ultrasonic were compared. According to the results, the digestion biogas of the sewage sludge treated by ultrasonic increase obviously, and the digestion biogas increment of the sewage sludge treated by single-frequency is 40.93%, higher than that treated by double-frequency. But the SCOD of the sewage sludge treated by double-frequency is 23.5%, more than that treated by single-frequency.

[Investigation of the sequestration of CO2 and carbonation process for the stabilization of MSW fly ash].

The sequestration of CO2 and carbonation process for the stabilization of fresh fly ash from municipal solid waste (MSW) incinerator were investigated. The purpose of this paper is to evaluate the influence of fundamental parameters affecting the stabilization of heavy metal of Pb and diffusivity and reactivity of CO2 (i. e. the water content and concentration of CO2). In addition, the major physical and chemical changes in fly ash after carbonation were investigated using XRD and SEM. It shows that 10% or more water content added to fly ash could remarkably accelerate the sequestration of CO2, compared with control samples without water. The sequestration of CO2 is not remarkable within 1 day in the air atmosphere for low content of CO2 (0.03%). The XRD analysis indicates that CO2 could combine Ca(OH)2 to form CaCO3 and CO2 could also combine heavy metal oxides to form heavy metal carbonate (i.e. from PbO4 to PbCO3). Aggregates of crystals of sheet and cylinder can be observed by SEM.