Summary: | 碩士 === 嘉南藥理大學 === 環境工程與科學系 === 103 === Botanical waste from constructed wetland (BWFCW) increases with the growth of wetlands in Taiwan. Some Researches tried to evaluate the feasibility of recovery BWFCW by composting but failed and reported it resulted from the non-biodegradable semi-cellulose, cellulose and lignin content in BWFCW. Therefore, it was impregnated with sodium hydroxide as a pretreatment process for the hydrolysis of semi-cellulose, cellulose and lignin in BWFCW. The feasibility of BWFCW pretreated by sodium hydroxide for the enhancement of composting efficiency was evaluated in the present work.
The cellulose and lignin content decreased after the pretreatment by soaking reed in different sodium hydroxide concentrations with various reaction times. The content of cellulose and lignocellulose in reed were decreased from 48.58% and 16.25% to 38.79% and 10.75%, respectively. Furthermore, the cellulose and lignin contents in finished compost from reed were 50.39% and 27.52%, decreasing to be cellulose 28.42% and lignin 9.02% after the pretreatment by soaking reed in sodium hydroxide solution.
The quality analysis of finished compost products showed the pH ranged between 7.51~8.3 and the C/N ratios were between 15.5~25.6. The moisture contents were in the range of 58.4% and 80.6%. The contents of N, P, K were 0.4~0.7%, 0.02~0.10%, and 0.43~0.88%, respectively. It was found that the moisture content and the C/N were slightly higher. The phosphorus content was kind of inadequate. The rest characteristics of the BWFCW composting products from reed pretreated by sodium hydroxide are in compliance with R.O.C. miscellaneous composting standard. Considering the time required for composting, product moisture content, pH, organic matter, heavy metal content, C/N ratio of decline in finished compost and compost compliance with R.O.C. relevant laws and regulations, the pretreatment of reed, It was concluded one reed pretreated by soaking in sodium hydroxide solution could promote composting efficiency.
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