生物柴油替代工业溶剂的消防安全可行性研究

通过对生物柴油的生产、利用等各个环节以及原料、产品等火灾危险性研究,分析了生物柴油储存稳定性好、闪点高、溶解性和安全性强等特点,探讨了其作为工业溶剂替代品的可行性。利用生物柴油作为工业溶剂,可以有效拓宽生物柴油利用空间,促使生物柴油产业的持续发展,同时能大幅度提高工业生产中使用溶剂的安全保障,减少工业生产中火灾爆炸事故的发生,带动经济效益显著提升。     

生物柴油企业火灾案例分析与风险探讨

生物柴油的消防安全问题长期以来被低估。统计了国内外近5年内发生的生物柴油装置火灾事故案例,分析生物柴油装置火灾事故的原因及特点,总结生物柴油及其生产企业的火灾危险性。分析得知,在生物柴油企业中,甲醇是火灾危险性最大且用量相对较大的火灾危险性物质;生物柴油、植物油以及甘油等高闪点液体在操作不当时同样可能引起严重的火灾事故。此外,由于忽视了因物质不纯或化学反应而出现的新的危险因素,也常常导致严重事故的发生。     

国际观察

JCB公司推出生物柴油发动机JCB公司最近推出适用于B20生物柴油Dieselmax型号的柴油发动机。生物柴油是一种清洁燃烧的燃料的名称,可利用可再生资源生产。生物柴油不包含石油,但它可以与任何级别的柴油合     

生物柴油的研究进展

本文介绍了生物柴油的生产原料,主要有植物油脂、动物油脂、微生物油脂和废弃无用油脂四大类,综述了生物柴油的优点以及国内外研究现状。     

城市污水处理厂污泥醇化制取生物柴油的研究现状

污水污泥作为污水处理的副产物,一直以来被作为废物进行处理处置,其高处理成本成为城市污水处理厂运营的沉重负担。然而,污水厂污泥含有较高的脂质,这些脂质可以通过醇化转化为生物柴油的主要成分脂肪酸甲酯。生物柴油作为清洁燃料,对环境友好,是一种绿色能源。从生物柴油的原材料现状出发,分析了以城市污水处理厂污泥为生物柴油原材料的可行性、影响污泥制取生物柴油产率的因素以及目前污泥制取生物柴油的经济成本,最后阐述了污泥制取生物柴油目前存在的问题和前景。     

生物柴油对模拟原油污染砾石释放油的影响研究

对生物柴油促进原油污染的砾石释放原油进行了模拟研究,讨论了生物柴油促进砾石上原油释放的可行性以及生物柴油投加量、投加方式对砾石上原油释放的影响.研究结果表明:生物柴油对砾石上原油的释放具有明显的促进作用;生物柴油的投加量越大,对砾石上原油的释放的促进作用越大,原油与生物柴油为2∶1时释放率为74.6%,4∶3时释放率为84.5%;生物柴油采用分批多次投加比一次性投加的效果更好,分三次投加的比一次性投加的在9d后可高出24.6%释放量.     

生物柴油的开发利用现状分析

生物柴油的开发利用有利于改善环境、促进农村发展和保障能源安全,讨论了生物柴油的性质和制备工艺技术,就各国生物柴油开发利用现状进行了综述。     

生物柴油对原油污染砂砾原油释放的影响

生物柴油是一种优良的溶剂,具有廉价易得、可降解、可再生等优点.研究生物柴油在海滩原油污染治理中的应用具有重要的意义.研究了生物柴油对原油污染砂砾释放油的影响,讨论了在不同生物柴油种类、投加量情况下生物柴油的作用效果.研究结果表明：不同种类生物柴油对原油污染砂砾释放油的促进效果不同,实验条件下菜籽生物柴油释放率最好（70.75%）,地沟油生物柴油最差（58.39%）;砂砾上原油的释放量随着生物柴油投加量的增加而增加,当生物柴油投加量达到一定值时,其对释放量和释放速率的促进都不再明显增加,实验条件下最适投加量为油污砂砾含油量的2倍.     

生物柴油在稠油降黏技术中的应用研究

将生物柴油应用于稠油降黏技术中,可以减少稠油降黏对轻质油的依赖。考察了生物柴油的掺加对稠油降黏效果的影响,结果表明,加入适量的生物柴油(<10%(w))可起到良好的降黏作用,降黏效果优于柴油。通过对稠油添加生物柴油和柴油得到的两种混合油进行红外表征,证实了添加生物柴油对稠油原油氢键的取代可以解离胶质和沥青质之间的聚集体,减弱稠油中胶质与沥青质之间的相互作用,从而达到降黏的目的。随着添加量的增加,极性影响作用增大,粘度进一步降低;但当生物柴油添加量超过15%(w)时,极性作用所表现的降黏效果已不明显。     

剩余污泥资源化合成微生物油脂制备生物柴油技术研究进展

污水处理厂产生的剩余污泥富含产油微生物以及脂质、有机质和氮磷等营养元素,是廉价易得的合成生物柴油的优质微生物油脂原料。目前,国内外采用剩余污泥合成生物柴油主要包含三种利用路径,其一是从剩余污泥中直接提取油脂制备生物柴油,操作简单、成本较低但生物柴油产率不高;其二是将剩余污泥中的产油微生物进行强化发酵培养,提高污泥中微生物油脂含量,再进行提取和甲酯化,能够有效提高油脂产量但需额外培养成本;其三是将剩余污泥进行物理化学、生物预处理转化为小分子物质作为产油酵母和产油微藻的培养基,可有效降低微生物油脂的合成成本,但生产过程较为复杂。三种技术途径各有优缺点和适用范围,未来进行应用时可根据污水处理厂实际情况进行选择。     

Status of biodiesel production using heterogeneous alkaline catalysts

This paper describes biodiesel production using heterogeneous alkaline catalysts instead of the conventional homogenous alkaline catalysts, such as NaOH, KOH or sodium methoxide, for the methanolysis reaction, in the search for more profitable and sustainable alternatives regarding biodiesel production. The heterogeneous catalytic process has many differences from that currently used in industrial homogeneous processes. The main advantage is that it requires lower investment costs, as there is no need for separation steps such as methanol/catalyst, biodiesel/catalyst and glycerine/catalyst. This paper also describes experimental work towards the development of new heterogeneous alkaline catalysts able to produce biodiesel from vegetable oils. The research has resulted in the selection of CaO and CaO modified with alkaline and alkaline earth metal catalysts. They show very good catalytic performances with high activity and stability. In fact, biodiesel (FAME) yields higher than 94% were observed in several consecutive reaction batches without expensive intermediate reactivation procedures. Therefore, those catalysts appear to be suitable for biodiesel production.     

Performance,combustion and emission characteristics of a single-cylinder constant speed compression ignition engine using soybean methyl esters

ABSTRACT

The present study was aimed to produce biodiesel from soybean oil and to investigate its characteristics. Soybean oil-based bio diesel properties are observed and tested in the fuel testing laboratory with standard procedures. It is found that soybean oil-based biodiesel has similar properties as that of diesel fuel. An experimental set-up was used in the study to analyse the performance, combustion and emission of soybean oil biodiesel with respect to normal diesel by using different blends (B20, B40, B60, B80 and B100). It is observed that there is no difficulty found in running the engine, but the performance of the biodiesel blends quite deviated from normal diesel. The combustion characteristics of the tested blends were in agreement with normal diesel. The carbon emissions are much lower for soybean oil biodiesel blends than diesel.     

蔓延火灾下钢框架结构抗火性能试验研究

为研究蔓延火灾下钢框架结构建筑室内火灾温度场、钢构件温度分布和位移的发展规律,对1个足尺的两层钢框架结构进行蔓延火灾试验,测量试验区域内关键位置的空气温度、钢构件温度和位移。试验结果表明：试验中火源房间内的火灾过程呈现4个明显的发展阶段,受火70min时室内火灾达到全盛,测得火灾烟气层最高温度730℃;受火82min时火灾从火源房间蔓延至邻近房间,导致了邻近房间内各受火钢构件温度峰值出现在不同时刻,同时,各构件历经扩散热烟气加热、直接受火加热和冷却降温3个阶段,呈现反复升降温的受火过程;受火过程中,钢构件温度变化显著滞后于火场温度,受火钢柱先后升温产生向上的轴向变形。与传统室内火灾相比,蔓延火灾扩大了火场范围和钢结构受火范围,对结构安全和人员安全造成更大威胁,因此在进行结构抗火设计时应得到充分考虑。     

Research on fire resistance test of a steel frame building under spreading fire

为研究蔓延火灾下钢框架结构建筑室内火灾温度场、钢构件温度分布和位移的发展规律，对1个足尺的两层钢框架结构进行蔓延火灾试验，测量试验区域内关键位置的空气温度、钢构件温度和位移。试验结果表明：试验中火源房间内的火灾过程呈现4个明显的发展阶段，受火70min时室内火灾达到全盛，测得火灾烟气层最高温度730℃；受火82min时火灾从火源房间蔓延至邻近房间，导致了邻近房间内各受火钢构件温度峰值出现在不同时刻，同时，各构件历经扩散热烟气加热、直接受火加热和冷却降温3个阶段，呈现反复升降温的受火过程；受火过程中，钢构件温度变化显著滞后于火场温度，受火钢柱先后升温产生向上的轴向变形。与传统室内火灾相比，蔓延火灾扩大了火场范围和钢结构受火范围，对结构安全和人员安全造成更大威胁，因此在进行结构抗火设计时应得到充分考虑。     

Synthesis and characterisation of biodiesel from Nigerian physic nut,castor bean,dika nut and sandbox seed oils

Biodiesel fuels were synthesised from Nigerian physic nut seed (Jatropha curcas), castor bean seed (Ricinus communis), dika nut (Irvingia gabonensis) and sandbox seed (Hura crepitans) oil. The direct base-catalysed transestetification process was employed in the biodiesel production using methanol and sodium hydroxide (NaOH) as alcohol and catalyst, respectively. The transesterification process involved 500 ml of J. curcas, castor bean seed, dika nut and sandbox seed oils, 100 ml of methanol and 1.0% of NaOH by weight for each oil. The process was carried out at different reaction temperatures in order to examine the effect of temperature on biodiesel yield of the oils. An average maximum biodiesel yield of 89.00% at 50 °C, 61.50% at 45 °C, 74.33% at 50 °C and 88.50% at 55 °C were obtained for Jatropha, castor, dika nut and sandbox oils, respectively. The calorific values of diesel decreased from 42.7 to 42.475, 41.48, 42.330 and 42.13 MJ/kg with a blend of 10% of physic nut, castor bean, dika nut and sandbox seed biodiesel, respectively. The calorific values of the produced biodiesel from physic nut, castor bean, dika nut and sandbox seed oils are 40.45, 30.50, 39.00 and 37.00 MJ/kg, respectively. The cetane number, kinematic viscosity at 40 °C and pour point of the produced biodiesel are 59.4, 4.20 mm²/s and?1°C for physic nut biodiesel; 50, 10.75 mm²/s and?45°C for castor biodiesel; 52, 3.20 mm²/s and?6°C for dika nut biodiesel and 50, 4.20 mm²/s and 6 °C for sandbox seed biodiesel, respectively. The results showed that the addition of biodiesel to diesel generally increases the density, kinematic viscosity, flash point and pour point but, on the other hand, reduces the calorific value of the produced blend.     

层次分析法在高层建筑火灾风险评估中的应用

本文介绍了层次分析法在高层建筑火灾进行评估时的步骤及方法,利用层次分析法将定量和定性的方法有机的结合起来,克服了高层建筑火灾风险评价因子难以量化的缺点,使不同的评价因子能够在同一水平下进行比较分析,通过举例给出结构模型及判断矩阵,根据判断矩阵进行层次单排序和一致性检验,从而确定火灾影响因子的权重,利用各影响因子的权重值对建筑进行防火设计或提出整改措施,对高层建筑火灾风险进行评估,     

Performance characteristics of palm kernel biodiesel and its blend in a CI engine

The full load performance characteristics of a diesel engine fuelled with palm kernel biodiesel and its blend with diesel fuel are presented in this paper. The biodiesel was synthesised from Nigerian palm kernel oil through a direct base catalysed transesterification process using sodium hydroxide and methanol as the catalyst and alcohol, respectively. The produced biodiesel was blended with neat diesel fuel at a ratio of 20% biodiesel to 80% diesel by volume. The engine torque, brake power, brake specific fuel consumption and brake mean effective pressure were determined for each of the fuels at 400 rpm intervals between 1200 and 3600 rpm. In other to establish a baseline for comparison, the engine was first run on neat diesel. The test results interestingly revealed that the fuel blend (B20) produced higher torque at low and medium engine speeds than neat diesel fuel and unblended biodiesel (B100). This suggests that it can be a suitable fuel for heavy duty engines that are required to develop high torque at low engine speeds. It was also observed that diesel fuel developed higher torque and brake power than the unblended biodiesel (B100) at all tested speeds and showed the least brake specific fuel consumption possibly because of its higher heating value. In all, the palm kernel biodiesel and its blend (B20) exhibited performance characteristic trends very similar to that of diesel fuel thus confirming them as suitable alternative fuels for compression ignition engines.     

可燃液体泄漏火灾分析

通过对可燃液体泄漏火灾的分析,介绍了可燃液体火灾的特点及可能产生泄漏的设备及原因.建立可燃液体火灾的数学模型,量化描述可燃液体的燃烧状态,并对上述分析的应用进行说明.     

The effect of engine emission on canola biodiesel blends with TiO2

The role of nanoparticles and nanofluid additives for biodiesel has gained consistent position in the current trend as they contribute to increase the performance of the engine with lower emission. In addition, additives also help to increase the engine reliability and lifespan. In this work, the effects of canola biodiesel blends of 20% proportions with diesel were investigated at 100% of engine load. The fuel is tested in a multi-cylinder water-cooled direct ignition (DI) engine. There are numerous notable works on nanofluid; however, the addition of TiO₂ nanoparticle as additive to produce canola biodiesel fuel is very limited. With the addition of the TiO₂ nanoparticle on Canola biodiesel blend in the DI engine, the exhaust property of gases such as CO, HC and NO_X is reduced. Furthermore, the combustion characteristics of the engine are improved. The canola biodiesel blends also resulted in lower NO_x emission as well as low smoke.     

Effect of temperature on the biodiesel yield from Nigerian physic nut,castor bean,dika nut and sandbox seed oils

Biodiesel fuels were synthesised from Nigerian physic nut seed (Jatropha curcas), castor bean seed (Ricinus communis), dika nut (Irvingia gabonensis) and sandbox seed (Hura crepitans) oil. The direct base-catalysed transestetification process was employed in the biodiesel production using methanol and sodium hydroxide (NaOH) as alcohol and catalyst, respectively. The trans esterification process involved 500 ml of J. curcas, castor bean seed, dika nut and sandbox seed oils, 100 ml of methanol and 1.0% of NaOH by weight for each oil. The process was carried out at different reaction temperatures in order to examine the effect of temperature on biodiesel yield of the oils. An average maximum biodiesel yield of 89.00% at 50°C, 61.50% at 45°C, 74.33% at 50°C and 88.50% at 55°C were obtained for Jatropha, castor, dika nut and sandbox oils, respectively. The result showed that the biodiesel yield from the various oils increased with temperature up to certain points beyond which it decreased.