Waste Removal with Incineration Methods: An Experimental Stud

Millions tons of waste are discharged worldwide every day; most of it is dumped in landfills or discharged to rivers and seas without prior treatment. However, while the demand for waste disposal capacities is increasing, the availability of suitable sites is on the decline. Waste has become a critical problem for industrial society, particularly in big cities and densely areas. Therefore, the need to avoid or reduce the waste and to recycle it will become an over important political and economic issue. However, disposal capacities will continue to decrease in spite of the reduction in the volumes of waste produced. For this reason it is necessary to coordinate and optimize waste management. One of these options is incineration. Incinerator emissions can be generalized into the following four categories: (1) particulate emissions; (2) gaseous emissions, such as sulfur dioxide (SO2), nitrogen oxides (NOx), carbon monoxide (CO), and hydrochloric acid (HCl); (3) metals; and (4) miscellaneous gas emission. Emitted gases such as SO2, HCl, and NO2 contribute heavily to acid rain and smog, and to the photochemical formation of ozone in smog in sunlight. SO2, NO2, and ozone have been proven to cause respiratory illness, and smog has been shown to cause increased death rate [1].

Various technologies to remove SO2 in flue gas have been studied. Dry and wet processes are commonly used. Dry process is superior to the wet one in terms (1) inexpensive, (2) easy handling, and (3) no produces of liquid waste. One of processes in dry process category is bag filter reactor that uses Ca(OH)2 as absorbent. However, this process posses shortcomings, i.e. low sorbent conversion and low gas separation efficiency [2].

To enhance the efficiency of gas ...

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...(calcination temperature = 800oC)

Figure 8 SEM micrographs of Ca(OH)2/DE sorbents: (a) DE and (b) Ca(OH)2/DE = 70:30

Figures 7 and 8 shows that the total porosity of the sorbent Ca(OH)2 is smaller than the sorbent Ca(OH)2/DE

4. Conclusion

The discussion of the results of this study can be concluded that the temperature, the stirrer speed and the reaction time has an important role on the conversion of the reaction between SiO2 with Ca(OH)2. The reaction temperature of 65oC produces the highest conversion, so it can be concluded that the reaction temperature is optimum at 65oC for the reaction between Ca(OH)2 with SiO2. The results also showed that the conversion reaches a constant at the reaction time of 20 minutes. The absorptive capacity of the Ca(OH)2/DE sorbent on methylene blue is greater than the absorptive capacity of Ca(OH)2 sorbent alone.