In this study, we proposed a new CO
2 fixation and reduction method for the paper industry using carbonized paper sludge (CPS) . The carbonaceous material in CPS is derived from CO
2 in the air. We considered the CO
2 fixation and reduction method using carbonization treatment which stably preserves carbonaceous material in PS. And this CO
2 fixation and reduction method is also considered to be a low cost and realizable carbon capture and storage (CCS) technology in the near feature.
We collected the CPS from PS cooperative treatment factory in Fuji city of Shizuoka pref., and analyzed by XRD, XRF and TG⁄DTA. The carbonaceous material in CPS was classified by chemical fractionation treatment using soil science method. Especially, the carbon content ratios of CPS were analyzed by CHNS⁄O Analyzer. The classifying results show that the almost all the carbonaceous material in CPS could be considered “humic mate-rial” that were chemically stable. From this analyzing results, the estimated total amount of CO
2 correspond to carbonaceous material in CPS was equal to 19.6 t-CO
2 form the daily carbonization treatment process. In this process, the CO
2 released from cellulose can be considered “carbon neutral”, however the CO
2 discharged from calcite should be calculated at 1.1 t-CO
2. At the same time, carbonization treatment needed 5,500 m
3 of LNG for combustion improver and 1,016 kWh of electricity for exhausting gas treatment. From these processes, the 12.5 t-CO
2 emission was estimated. The total amount of COO
2 storage in the daily carbonization treatment was calculated at 6.0 t-CO
2, and it was equal to 133.1 kg-CO
2 in1t CPS. Applying the carbonization process to PS treatment enables to reduce 214.1 kg-CO
2 in1t dried PS (DPS) as compared to applying normal incineration process. On the other hand when PS is substituted instead of crude oil for fuel in boilers, the reduction of CO
2 is estimated at 358.3 kg-CO
2⁄t (DPS)
These results show that the carbonization and thermal utilization processes to PS can be considered as a CO
2 reduction method. And only carbonization process can be considered as CO
2 fixation process in limited usage by returning it to the soil as soil conditioner.
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