纤维素酶气相双动态固态发酵

为了充分利用纤维素酶固态发酵的优势,提出了纤维素酶气相双动态固态发酵的方式.研究结果表明:在优化条件下(最佳压力脉冲范围、脉冲频率及气体内循环速率),发酵温度得到较好地控制,9.0cm高的填料层中最大温度梯度为0.12℃/cm;以汽爆秸秆为底物,发酵水活度得到较好的保持;动态培养发酵周期(60h)比静态发酵周期(84h)缩短了 1/3,酶活(20.36IU/g)比静态酶活(10.82IU/g)提高了1倍,压力脉动固态培养的料层上中下微生物生长状况均匀一致,且疏松,而静态固态发酵的料层中部几乎没有菌体生长利用气相双动态固态发酵可为纤维素酶大规模生产奠定基础.     

生物膜反应器降解生物质气化洗焦废水

陶瓷球作为固定介质 ,接种本实验室保藏的Pseudomonassp1和Pseudomonassp2混合菌种 ,应用生物膜反应器处理生物质气化过程中产生的洗焦废水 ,对反应器运转整个过程的进出水COD浓度、进出水苯、萘、菲、吡啶、喹啉、异喹啉的含量、反应器内和反应器出水含菌量进行测定 ,以了解生物膜反应器处理生物质气化洗焦废水的特性 .结果表明 ,反应器经挂膜、增菌后 ,可达到稳定运转状态 ,有效的控制了反应器内微生物细胞的流失 ,使生物质气化洗焦废水中的有机物得到较好去除 .     

Updraft gasification of juniper wood biomass using CO2–O2 and Air (N2–O2)

Biomass gasification is being considered as one of the most promising technologies for converting low-quality solid biomass fuel into gaseous fuel. Redberry juniper (Juniperus pinchotii), one of the woody species that dominate uncultivated lands in the southern great plains, USA, may have a great potential for bioenergy utilization. In this study, the results of gasification of juniper are presented. Juniper wood chips were gasified in an adiabatic fixed bed updraft gasifier using air and the mixture gas of carbon dioxide and oxygen (CO₂:O₂) as gasification medium. The effect of gasification parameters such as moisture contents, gasification mediums, and gasification temperature on produced gas properties and the tar yield were investigated. It was observed that oxy fuel gasification (the reaction of woody fuels with carbon dioxide) of juniper resulted in the increase of production of carbon monoxide, especially at higher peak gasification temperatures. As a result, the CO₂ gasification resulted in producing higher heating value gas (6264 kJ/nm³ with dilution of CO₂ and 19,750 kJ/nm³ inert free) compared to air gasification. For air gasification, it was observed that the updraft gasification produced large amount of the tar in the product gas (more than 100 g/nm³) for the fuels with moisture content between 6% and 11%. Generally, the tar yield increased with the increase of equivalence ratio (er) and moisture content. However, when the fuel moisture content reached 23.5%, the tar yield reduced significantly due low gasification temperature which reduced the less tar cracking.     

活性焦吸附—曝气生物滤池处理煤气化废水生化出水

采用活性焦吸附—曝气生物滤池（BAF）工艺对煤气化废水生化出水进行深度处理。在活性焦投加量2 g/L、吸附时间2 h、BAF生化停留时间4 h的条件下,总COD去除率为85.4%,最终出水平均COD为45.2 mg/L,满足后续双膜法回用工艺要求（COD≤50 mg/L）。活性焦对致色的大分子有机物具有较好的吸附效果,吸附后废水的色度从300倍降至60倍,同时耗氧速率加快,可生化性提高。活性焦的吸附以物理吸附为主,吸附出水没有急性毒性。三维荧光光谱显示：各单元对于酚类的去除均有贡献,小分子组分中的酚类几乎全被去除。     

The effect of pyrolysis atmosphere on bio-oil yields and structure

A food industry waste, almond shell, was pyrolyzed under three different environment static, nitrogen, and steam to produce bio-oil and its derivatives. The oil yield obtained at pyrolysis temperature of 600°C was 24.23% in a static atmosphere, whereas it increased to 27.25% and 33.05% in nitrogen and steam atmospheres, respectively. The bio-oil obtained under steam atmosphere is very efficient due to the production of high liquid and gas yields. Moreover, co-feeding steam during the pyrolysis altered the bio-oil structure by increasing the aliphatics and reducing the asphaltenes. Moreover, steam treatment also increases H/C and heating value of bio-oils. According to the obtained results, steam pyrolysis is an alternative option for future applications in refineries.     

废弃印刷线路板熔融盐气化特性研究

在熔融盐气化炉中进行废弃印刷线路板气化实验,考察了空气当量比对气体产率、气体热值、碳转化率以及气化效率的影响,并对N2气氛下线路板在熔融盐反应器中裂解液体产物通过气质联用仪进行了分析.结果表明,气体产率和碳转化率随着空气当量比增加而增加,空气当量比增加到40%时,气体产率和碳转化率分别达到840 mL·g-1和96%;气体产物热值随着空气当量比增加而减少,气化效率随着空气当量比的增加先增加然后减少,在20%空气当量比气化效率达到最大值94%.液体产物的主要成分为苯酚、2-甲基苯酚、萘等,表明线路板在熔融盐气化炉内的反应过程中,苯环结构上的长链烷烃脂肪烃支链得到脱除,苯基C6H5-O的断裂得到加强,同时发生芳构化反应.     

我国石化企业节水措施探讨

归纳了目前我国石化企业节水工作的主要内容;探讨了用水管理、蒸汽凝结水回收和污水回用中的部分技术问题;介绍了节水工作的基本流程、技术特点、使用范围和应注意的问题等。     

蒸汽发生器管束外表面的应力腐蚀破裂规律(续一)

报道了某核动力系统蒸汽发生器,因管束的应力腐蚀破裂而发生严重泄漏事故的原因和规律.采用肉眼宏观检查、着色探伤、超声波探伤和单管泵压试验等方法探明了蒸汽发生器的应力腐蚀破裂特点和在管束表面上的立体分布规律;采用电子探针、电子显微镜、X射线衍射仪和扫描电镜等微观分析技术查明了产生应力腐蚀破裂的原因和文中所述分布规律的原因,并提出了一些改进办法.不仅为后来的蒸汽发生器的设计、制造和运行提供了依据,而且也为应力腐蚀破裂的研究,提供了大量的实际资料.展示了众多在蒸汽发生器的实际运行过程中所产生的应力腐蚀破裂形貌的照片,并列出了形成各种规律的统计数据.     

Research on low emission MSW gasification and melting system

In order to eliminate secondary pollution caused by municipal solid waste (MSW) incineration, a MSW gasification and melting process is proposed. The process is expected to reduce the emission of pollutants, especially heavy-metals and dioxins. In this paper, the combustible components of MSW and simulated MSW were gasified in a lab-scale fluidized bed at 400°C–700°C when the excess air ratio (ER) was between 0.2 and 0.8. The experimental results indicated that the MSW could be gasified effectively in a fluidized bed at approximately 600°C–700°C when excess air ratio was 0.2–0.4. The melting characteristics of two typical fly ash samples from MSW incinerators were investigated. The results indicated that fly ash of pure MSW incineration could be melted at approximately 1,300°C and that of MSW and coal co-combustion could be melted at approximately 1,400°C. When temperature was over 1,100°C, more than 99.9% of the dioxins could be decomposed and most of the heavy-metals could be solidified in the slag. Based on the above experiments, two feasible MSW gasification and melting processes were proposed for low calorific value MSW: (1) sieved MSW gasification and melting system, which was based on an idea of multi-recycle; (2) gasification and melting scheme of MSW adding coal as assistant fuel. __________ Translated from Environmental Science, 2006, 27(1): 69–73 [译自: 环境科学]     

Experimental study on MSW gasification and melting technology

In order to develop municipal solid waste (MSW) gasification and melting technology, two preliminary experiments and a principle integrated experiment were fulfilled respectively. The gasification characteristics of MSW are studied at 500-750℃ when equivalence ratio (ER) was 0.2-0.5 using a fluidized-bed gasifier. When temperature was 550-700℃ and ER was 0.2-0.4, low heat value (LHV) of syngas reaches 4000-12000 kJ/Nm3. The melting characteristics of fly ash were investigated at 1100-1460℃ using a fixed-bed furnace. It was proved that over 99.9% of dioxins could be decomposed and most heavy-metals could be solidified when temperature was 1100-1300℃. The principle integrated experiment was carried out in a fluidized-bed gasification and swirl-melting system. MSW was gasified efficiently at 550-650℃, swirl-melting furnace maintains at 1200-1300℃ stably and over 95% of fly ash could be caught by the swirl-melting furnace. The results provided much practical experience and basic data to develop MSW gasification and melting technology.