【作者】 李贺；

【导师】 蔡伟民；

【作者基本信息】 哈尔滨工业大学 ， 环境科学与工程， 2011， 博士

【摘要】 伴随社会的发展,支柱性产业能耗高、效率低、对传统能源的过度依赖,新能源开发不足,导致了生态环境破坏严重,制约了我国的可持续发展。调整能源结构,实现结构多样化,发展清洁能源、加大新能源利用已成为我国能源结构调整的主攻方向。将厌氧折流板工艺与微生物燃料电池工艺相结合,设计开发了折流板管状空气阴极微生物燃料电池(baffled tubular air-cathode MFC, BTAMFC)(200810063876.5及PCT/CN2009/070168),该反应器既保留了厌氧折流板工艺在废水处理中的优势,又可进行电能的生产,提高了回收的经济效益。构建了BTAMFC的基本构型——单格室BTAMFC(Single-compartment BTAMFC,SBTAMFC)。考察了阳极结构对SBTAMFC的影响,三维立体阳极结构更有利于体系的产能与废水的去除。与碳板阳极BTAMFC相比,三维立体阳极BTAMFC总内阻由原来的19.8?降低为12.1?,最大功率密度升高至582.4 mW/m2, COD去除率也从47%增加至88%。对比了连续流与间歇流运行方式,连续流运行方式有效地提高了体系的产电性能。间歇流运行BTAMFC的总内阻增加了7.4?,功率密度降低至407.1mW/m2,COD去除率变化不明显。考察了分格数对BTAMFC的影响,将单室BTAMFC构建成双室BTAMFC(dual-compartment BTAMFC, DBTAMFC),不仅增大了输出电能,还增加了体系对废水的去除能力。以1g/L葡萄糖为底物,当HRT=6h时,最大功率密度为15.2 W/m3,COD去除率为88%,内阻为13.7?。随着进水负荷从4.11 kg COD/ (m~3 NAC·d)升高至16.0 kg COD/ (m~3 NAC·d)时,COD去除率从88%降低至70%。在此过程中,电池的内阻变化不大,始终低于15?;当进水负荷为9.60 kg COD/ (m~3 NAC·d)(HRT=2.5h)时,拥有最大输出功率密度(20.8 W/m3);最大库伦效率(48%)在6.96 kg COD/ (m~3 NAC·d)(HRT=3.5h)时获得,因此该体系最佳的水力停留时间范围为2.5-3.5h。考察了长期运行对电池性能的影响,结果显示,电池经过10个月的稳定运行,仍保持较高的电能输出及COD去除率,输出电压降低了6.4%,最大功率密度降低为原来的48.4%,但仍能输出7.9W/m3的电能, COD去除率由原来的88%升高至90%。进一步说明DBTAMFC体系的稳定性较好,适合于长期运行,电池的寿命至少在10个月以上。进一步增加分格数,优化BTAMFC的产电性能及废水处理效果。由双格室DBTAMFC增加成五格室BTAMFC ( Five-compartment BTAMFC ,FBTAMFC),体积增大了4.5倍。进水葡萄糖浓度为5 g/L,与DBTAMFC相比,各个格室在1000?下输出的电压并未改变,总输出功率从DBTAMFC的20.8 W/m~3提高至54.7 W/m3,总COD去除率为86%。各个格室的欧姆内阻相同,但源于电荷转移内阻及扩散内阻的差异使得总内阻相差不到1?(12-13?),说明了BTAMFC的内阻不会随着格室数的增加而增大,为BTAMFC分格数进一步增加提供了参考数据。除第一格室内阻外,其余各格室内阻均小于DBTAMFC。各格室按从前至后的顺序COD去除率分别为67%、25%、32%、3.5%和11%,揭示了BTAMFC体系一个普遍的规律,即第一个格室主要偏向于废水处理,超过50%以上的进水COD在此格室内得以去除。五格室BTAMFC在无回流时,各格室的最大功率密度均降低,总功率密度降低了13.6 W/m3,但总COD去除率由原来的86%升高至94%。虽然损失了部分电能,但节省了投资与运行费用,提高了废水处理效果。增加底物浓度(由5g/L增至10g/L)大大降低了第一、三格室的产电性能使得10g/L时总功率密度降低了33.9 W/m3,但COD去除率保持在94%。将秸秆纤维素燃料乙醇洗液废水稀释后直接用于DBTAMFC中产电,最大输出功率密度为10.7 W/m3, COD去除率达89.1%,并伴有脱色效果。首次将秸秆纤维素燃料乙醇醪液废水直接应用于FBTAMFC产电,总功率密度为20.8 W/m3,COD去除率为95%。首次将BTAMFC工艺与CSTR(产酸相)、EGS(产甲烷相)及SBR反应器(好氧段)的废水处理工艺联合应用,将秸秆纤维素燃料乙醇醪液废水SBR工艺段出水作为单室BTAMFC底物产电,电压由412mV降低至296mV,最大功率密度为2.7W/m3,出水COD可达96mg/L,去除率为72%,出水色度明显下降,为MFC工艺在废水领域内应用提供了新的方法。综上所述,BTAMFC可直接应用于处理高浓度高负荷的有机工业废水中,且具有一定的脱色效果及抗负荷及毒物冲击的特性。更多还原

【Abstract】 Nowadays, the contradiction of supply over demand in energy has become very obvious. Sustainable development is seriously hampered by resources, energy and environment. The power supply structure should be optimized based on structural adjustment. Development of techniques of energy from wastewater has become the main direction of energy restructuring.Based on the techniques of anaerobic baffled reactor, a baffled tubular air-cathode MFC (BTAMFC) configuration was designed (200810063876.5 and PCT/CN2009/070168). It was indicated that configuration of BTAMFC reserved excellent efficiency of ABR process in wastewater treatment. Modified parts (the graphite plate used as the guide plate and plastic tubes inserted in the reactor) did not affect removal efficiency of wastewater.Single-compartment BTAMFC (SBTAMFC) was developed. In order to establish a rational system, the construction of anode was selected. A three dimensional anode made from graphite granules was beneficial to both in COD removal and electricity generation. The internal resistance of MFC was decreased from 19.8? to 12.1?; the maximum power density was increased to 582.4 mW/m2. The COD removal rate was from 47% up to 88%. The charge-transfer resistance and diffusion resistance of the cell was affected by operational mode. In fed-batch mode, the internal resistance was increased 7.4?. Compared with that under continuous mode, the maximum power density was reduced to 407.1mW/m2; however the COD removal rate was kept in the same lever. Consequently continuous mode was more suitable for single-compartment BTAMFC.Dual- compartment BTAMFC (DBTAMFC) was set-up under continuous flow. With 1g/L glucose fed as substrate, an average voltage of 652 mV was obtained under the external resistance of 1000 ? (30 oC). The maximum power density was 15.2 W/m~3 with the chemical oxygen demand (COD) removal rate of 88%. The overall resistance was 13.7 ? while ohmic internal resistance was 10.8 ?. Average COD removal rate was 70% to 88%, when COD loading varied from 4.11 kg COD/ (m~3 NAC·d) to 16.0 kg COD/ (m~3 NAC·d). The maximum power density was 20.8 W/m~3 at HRT 2.5 h and COD loading 9.60 kg COD/ (m~3 NAC·d). The maximum coulombic efficiency of 48% was obtained when HRT was controlled at 3.5 h. Therefore, in DBTAMFC system, the optimized HRT could be regarded as 2.5 h to 3.5 h. DBTAMFC was operated for at least ten months. During this period, the HRT faceters were determined and a high volumetric loading was used in this system. And DBTAMFC was then running at the same condition as set-up. It was indicated that the cell was run well and kept a stable voltage and COD removal rate. The voltage output was decreased slightly, only 6%. Although decreased 48.4%, the maximum power density was still kept 7.9 W/m3. The COD removal rate was increased from 88% to 90%. It was documented that the DBTAMFC was stable and suitable for a long-term operation, and the life of the cell was at least ten months.The volume of BTAMFC was increased 4.5 times from two compartments to five compartments. During this process, the electrogenic performance of BTAMFC was enhanced. The voltage out-put was kept stably, and maximum power density was up to 54.7 W/m3. As a result, the COD removal rate was increased obviously. 5g/L glucose was used as the substrate, and the COD removal rate was kept higher than 85%. The internal resistance was stable between 12? and13?, indicating the internal resistance was not changed by the adding of BTAMFC conmpartments. It was afford to further increasing of compartments. The effluent of each compartment was 67%, 25%, 32%, 3.5% and 11% in sequence, which indicated that more than half of influent COD was removed in compartment 1. Without the reflux in five-compartment BTAMFC, the maximum power density in each compartment was reduced, leading to the total maximum power density was decreased 13.6 W/m3. However, the COD removal rate was increased from 86% to 94%. Although the power density was reduced 24.9%, the COD removal was enhanced, and economic effectiveness was recovered. BTAMFC was affected by the concentration of influent. The performance of power production in compartment 1 and 3 was declined following the increasing of glucose concentration. When FBTAMFC was fed with 10 g/L glucose, the maximum power density was decreased 33.9W/m3. Nevertheless the COD removal rate was kept at 94%, when the influent COD was up to 10600mg/L. It was apparently shown that BTAMFC had good capacity of resisting the shock loads. The wastewater from COFCO’s corn stover cellulosic ethanol plant was directly treated by BTAMFC for the first time. The liquid from corn stover steam explosion process (COD=7160±50 mg/L) was treated by DBTAMFC, and the maximum power density was 10.7 W/m~3 with the average COD removal rate was 89.1%. The maximum power density was 10.7 W/m3, while the volumetric loading rate was as high as 29.5 kg COD/ (m~3 NAC·d). When FBTAMFC was used distillate wastewater as the substrate, the total maximum power density of 20.8 W/m~3 was obtained with the COD removal rate of 95%. Wastewater treatment process was designed and including CSTR ( hydrolysis-acidification reactor ), EGSB ( methanogenic reactor ), SBR (aerobic reactor ) and single-compartment BTAMFC. The effluent from SBR process was used as the substrate for the BTAMFC. The maximum power density was 2.7 W/m3. The COD removal rate was 72 %, and the COD for effluent of BTAMFC was below 100mg/L. The dark influent wastewater became light after treatment by BTAMFC, which also addressed the discoloring ability of the system. It was illustrated that BTAMFC preferred to high-concentration industrial wastewater treatment, which brought a good application prospect for this configuration. It was provided a new way of thinking in MFC technology for the application in the field of wastewater treatment.更多还原