以催化水熱液化法將生廚餘轉製生質燃料油

Conversion of Leftovers Biomass to Bio-oil Products by Catalytic Hydrothermal Liquefaction

周珈逸(Ka-Iat Chau)

指導教授 ： 張慶源

國立臺灣大學/工學院/環境工程學研究所/碩士(2017年)

https://doi.org/10.6342/NTU201703802

摘要

每天生活中會產生很多廚餘，而廚餘會造成水污染、焚化爐壽命縮短、家庭污水排放有機濃度增加等問題，故本研究利用廚餘(高麗菜)為原料，以水熱液化法(hydrothermal liquefaction, HTL)、催化水熱液化法(catalystic hydrothermal liquefaction, CHTL)把生質物轉製成生質油品。而因影響水熱液化法反應的參數甚多，故會以原物料乾濕基、反應溫度(T)、反應時間(tr)、均相催化劑、異相催化劑及氫氣起始壓力來探討對固、液、氣體產物之影響變化。
在各產物中生質原油(bio-oil, BO)為本研究之目標產物。而BO分成HSO (hexane soluble oil, 輕質油品)與HWIASO (hexane and water insoluble while acetone soluble oil, 重質油品)。HWIASO的黏滯性較HSO高。於613 K和30分鐘時，結果顯示，以濕基原料及乾基原料加入5 wt% K2CO3均相催化劑進行水熱液化法，濕基和乾基的BO產油率(YBO)分別為35.53和19.33 wt%，HSO產油率(YHSO)分別為6.75和2.19 wt%，HWIASO產油率(YHWIASO)分別為28.78和17.14 wt%，濕基都比乾基高。其濕基和乾基的固體轉化率(XS)分別為86.59和83.45 wt%。反應時間方面，太短可能會沒有辦法完全分解纖維素，而木質素更是難以分解。加入均相催化劑K2CO3有助於YBO及XS的提高。濕基未加入K2CO3其YBO和XS分別為23.6和83.91 wt%。而YHSO=2.7 wt%，YHWIASO=20.9 wt%。進一步利用模擬蒸餾作分析顯示濕基進料加入K2CO3 (Case KW)其HSO油品碳數主要在C6-C18，且低碳數之碳氫化合物(HCs)多於未加K2CO3者，油品性質有所提升並接近船舶用油。濕基進料加入5 wt% K2CO3及10 wt% Mo2C/γ-Al2O3異相觸媒(Case KWM)，其YBO=41.67 wt%，YHSO=3.16 wt%，YHWIASO=38.51 wt%，Xs=89.99 wt%。結果顥示適量的Mo2C/γ-Al2O3會促進生質物之轉化，BO及HWIASO之生成。未加Mo2C/γ-Al2O3但加入起始壓力100 psig之氫氣(Case KWH)，其YBO和XS分別為30.15和87.48 wt%。YBO下降，但XS稍增。此外，HSO產率由6.75增至9 wt%，而HWIASO產率由28.78降至21.15 wt%。結果顥示加氫可增進固體之轉化及HWIASO之再裂解，提升HSO之生成。濕基進料加入5 wt% K2CO3、10 wt% Mo2Cγ-Al2O3及100 psig H2 (Case KWMH)時，其YBO=35.52 wt%，YHSO=5.74 wt%，YHWIASO=29.78 wt%，XS =88.12 wt%。加入H2可使Mo2C/γ-Al2O3所增進產生的HWIASO進一步裂解生成HSO。比較上述程序，於濕基進料添加K2CO3程序中加入H2可提升YHSO，若加入Mo2C/γ-Al2O3則可提YBO高。
程序KW、KWM、KWH、KWMH所得HBO之熱值分別為39.51、42.56、36.01、43.25 MJ/kg，而HWIASO之熱值則分別為32.88、42.32、42.15、45.43 MJ/kg。同時加入Mo2C/γ-Al2O3和H2可同時增加HBO和HWIASO之熱值。加入Mo2C/γ-Al2O3時，無論不加H2或加H2，其HBO和HWIASO之熱值均近於或高於航空油品Jet A-1之43.15 MJ/kg。

關鍵字

廚餘 ； 高麗菜 ； 水熱液化 ； 均相催化劑 ； 異相催化劑

並列摘要

Lots of leftovers are generated everyday from the human activities. Theses leftovers cause water pollution, incineration furnace life shortages, and household sewage discharge with increased organic concentration. This research studied the use of these leftovers choosing cabbage (CBG) as an example of biomass material via the methods of hydrothermal liquefaction (HTL) and cataystic hydrothermal liquefaction (CHTL) to convert them into bioenergy. The main influent factors of HTL and CHTL include dry and wet feeding of biomass, reaction temperature (T), reaction time (tr), hydrolysis catalyst, heterogeneous catalyst, and hydrogen initial pressure. The characteristics of solid, liquid, and gas products were analyzed.
The key tarage product from HTL of CBG is bio-oil (BO), which includes hexane soluable oil (HSO) and hexane and water insoluble while acetone soulble oil (HWIASO). HWIASO has a higher viscosity than HSO. At 613 K and 30 min with addition of 5 wt% K2CO3, the wet CBG feeding gives the yields of BO (YBO), HSO(YHSO), and HWIASO (YHWIASO) of 35.53, 6.75, and 28.78 wt% and conversion of solid (XS) of 86.59 wt% higher than dry CBG feeding with corresponding yields of 19.33, 2.19, and 17.14 wt% and XS of 83.45 wt%, respectively. If the reaction time is too short, cellulose and lignin may not be completely decomposed. After adding hydrolysis catalyst K2CO3, the YBO and XS are increased. For the case of wet feeding without K2CO3, the YBO, YHSO, YHWIASO, and XS are 23.6, 2.7, 20.9, and 83.91 wt%, respectively. The simulated distillation (SDT) results show that HSO from the case of wet feeding with 5 wt% K2CO3 (denoted as Case KW) posses carbon number distribution mainly between C6-C18 close to that of boat oil. It also contains more hydrocarbons (HCs) of low carbon number than those from the corresponding case without K2CO3. For Case KW with addition of 10 wt% Mo2C/γ-Al2O3 catalyst (symboled as Case KWM), the YBO, YHSO, YHWIASO, and XS are 41.67, 3.16, 38.51, and 89.99 wt%, respectively. A proper addition of Mo2C/γ-Al2O3 enhances the solid conversion XS and the productions of BO and HWIASO. As the hydrogen with initial pressure of 100 psig was added to Case KW (noted as Case KWH), the results give YBO, YHSO, YHWIASO , and XS of 30.15, 9, 21.15, and 87.48 wt%, respectively. The presence of H2 increases the XS and YHSO, while decreases the YHWIASO which then in ture reduces the YBO. With the presence of both Mo2C and H2 (called as Case KWMH), the YBO, YHSO, YHWIASO, and XS are 35.52, 5.74, 29.78 and 88.12 wt%, respectively. Thus, addition of H2 to Mo2C/γ-Al2O3 can further crack the HWIASO formed by the enhancement of Mo2C/γ-Al2O3 to produce HSO, decreasing the YHWIASO while increasiong the YHSO.
For Cases KW, KWM, KWH, and KWMH, the heating values of HBO are 39.51, 42.56, 36.01, and 43.25 MJ/kg, while those of HWIASO are 32.88, 43.32, 42.15, and 45.43 MJ/kg, respectively. The simultaneous presence of Mo2C/γ-Al2O3 and H2 improves the heating values of both HBO and HWIASO. The addition of Mo2C/γ-Al2O3 with or without the presence of H2 gives HBO and HWIASO possing heating values close or higher than that of Jet A-1 aviation oil of 43.15 MJ/kg.

並列關鍵字

leftovers ； Cabbage ； Hydrothermal liquefaction ； hydrolysis catalyst ； heterogeneous catalyst

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