Effects of sawdust soil amendment on the soil, growth and yield of Solanum esculentum Linn. in waste engine oil-polluted soil

This study investigated the effects of sawdust as a soil amendment on certain growth parameters of Solanum esculentum Linn. grown in soil polluted with various concentrations of waste engine oil, and changes in the physicochemical proper- ties of the soil. The purpose was to assess the soil remediation potentials of sawdust in waste engine oil-polluted soil. The experiment was divided into three regimes： control （air-dried soil without waste engine oil and with clean sawdust）, pol- luted （waste engine oil-contaminated soil）, and amended （oil-polluted soil amended with sawdust）. Enough 3-kg soil samples were sieved and air-dried to prepare five treatment levels of waste engine oil-contaminated soil （30 mL, 1%; 60 mL, 2%; 90 mL, 3%; 120 mL, 4%; and 150 mL, 5%）, as well as five additional treatment levels （the same amounts ofoil contamination） in soil amended with sawdust. The treatment levels were replicated five times in a completely randomized design. A nursery bed was planted with a hybrid tomato variety （Roma V F） obtained from National Horticultural Research Institute （NIHORT） in Ibadan, Nigeria. During the maturation period, the growth parameters such as plant height, number of leaves, and number of branches per plant were determined and then the harvested plants were oven dried at 70 ℃for 48 hours to determine their dry weights. The effects of the sawdust amendment on the soil were assessed by determining the soil pH （glass electrode pH meter）, total nitrogen （Kjeldahl method）, total phosphorus （Bray-1 solution）, and potassium （on the leacheate by a flame photometer）. Chromium, lead, and cadmium contents were determined using an atomic absorption spectrophotometer. Analysis of variance and a Duncan multiple-range test were employed to test significant differences in the soil properties of the three regimes. The growth performance ofSolanum esculentum Linn. in the amended regime （soil with sawdust） at the 150-mL waste engine oil-contamination level was significantly higher than in the polluted regime （soil without sawdust）. After plant harvest, the pH of the soil was shown to be clearly affected by the addition of waste engine oil. The control soil （air-dried only, no sawdust, no oil） had the highest pH value, 6.60, which was significantly different from the pH values at other levels of waste engine oil contamination. However, when amended with sawdust, the control soil had a significantly lower pH value than the unamended control soil. This study further demonstrates that sawdust has the potential of amending waste engine oil-contaminated soil for increasing tomato growth performance because it is capable of increasing the soil nutrient content and reducing the soil total hydrocarbon content.

Engine performance and combustion characteristics of a direct injection compression ignition engine fueled waste cooking oil synthetic diesel

Biodiesels produced from various feedstocks have been considered as alternative fuels used in internal combustion engines without major modifications.This research focuses on producing biodiesel from waste cooking oil(WCOSD)by the catalytic cracking method using MgO as the catalyst and comparing the engine operating characteristics of the test engine when using WCOSD and traditional diesel(CD)as test fuels.As a result,the brake power of the test engine fueled WCOSD,and traditional diesel is similar.However,the engine fuel consumption in the case of using WCOSD is slight increases in some operating conditions.Also,the nitrogen oxides emissions of the test engine fueled WCOSD are higher than those of CD at all tested conditions.The trend is opposite for hydrocarbon emission as the HC emission of the engine fueled by WCOSD reduces 26.3%on average.The smoke emission of the test engine in case of using WCOSD is lower 17%on average than that of CD.However,the carbon monoxide emissions are lower at the low and medium loads and higher at the full loads.These results show that the new biodiesel has the same characteristics as those of commercial biodiesel and can be used as fuel for diesel engines.

Combined Effect of a Catalytic Reduction Device with Waste Frying Oil-Based Biodiesel on NOx Emissions of Diesel Engines

Internal combustion engines with application in automobiles and other relevant industries constitute significant environmental pollution via the release of toxic exhaust gasses like carbon monoxide (CO), hydrocarbons (HC), particulate matter (PM), and nitrogen oxide (NOx). Engine researchers and manufacturers are challenged to develop external and internal measures to ensure environmentally friendly solutions to accommodate and conform to the growing list of emission standards. Therefore, this work presents an experimental investigation of the NOx emission profile of a diesel engine that is fuelled and fitted with waste frying oil-based biodiesel and catalytic converter. Using a single-cylinder, four-stroke air-cooled CI engine at a constant speed of 1900 rpm and different loadings of 25%, 50%, 75%, and 100%;fitted with a catalytic converter at the exhaust outlet of the engine and linked to a dynamometer and a gas analyser, an experiment was conducted at biodiesel/diesel volume blends of B0 (0/10), B5 (5/95), B20 (20/80), B30 (30/70), B70 (70/30), B100 (100/0);and 30% concentration (v/v), 0.5 litre/hr flow rate of aqueous urea from the catalytic converter. The results show an increasing NOx emission as the biodiesel component increased in the blend. The catalytic converter showed a downward NOx reduction with a significant 68% reduction in efficiency at high exhaust gas temperatures. It is concluded that the combined utilisation of waste frying oil-based biodiesel and the catalytic converter yields substantial NOx emission reduction.

Use of waste plastic oil as a fuel in reactivity-controlled compression ignition engines:a bibliometric investigation from 2017-23

Waste plastic oil,generated through the pyrolysis of plastic without oxygen,known as plastic-to-fuel conversion,stands as a promising alternative fuel.This research employs bibliometric analysis,a quantitative method,to comprehensively assess publications in the domain of waste plastic oil integration within reactivity-controlled compression ignition engines.Utilizing Scopus as the primary repository post-2017,the study categorizes information into pivotal aspects,including influential journals,countries,authors,affiliations,document types,thematic areas,sponsors and keywords.The analysis reveals significant contributions from diverse nations,prominently India,China,Turkey and Malaysia.Noteworthy is the prevalence of Energy,Engineering and Chemical Engineering as thematic focal points,with the journal Fuel leading the count followed by the journal Energy emerging as a prominent conduit.Institutional contributions are prolific,led by Gandhi Institute of Technology and Management University and Vellore Institute of Technology.Renowned authors‘Gugulothu S.K’and‘He Z’play a pivotal role in shaping the discourse.The National Natural Science Foundation of China stands out as a primary patron.This bibliometric analysis provides a structured understanding of waste plastic oil integration in reactivity-controlled compression ignition engines,laying the groundwork for future research avenues.The study identifies potential research platforms beyond Scopus,including Web of Science,CrossRef,Science Direct and Google Scholar,as valuable repositories for further exploration.Moreover,after careful observation of the research articles published by the top 10 authors as found in the study,it was found that the authors share a few common characteristics that helped them in advancing the understanding and application of waste plastic oil in reactivity-controlled compression ignition engines.These are also summarized in the present study with supporting data.

Diffusion and Regeneration Mechanism of Waste Composite Oils Rejuvenator in Aged Asphalt

The physical performance of recycled asphalt was used as the main evaluation index to study the optimal range of a self-made rejuvenator.Through the penetration,viscosity and gel permeation chromatography(GPC)tests,the diffusion degree of the rejuvenator under different temperatures and time process was analyzed,and the diffusion efficiency of the rejuvenator was evaluated from the macro and micro perspective.The regeneration mechanism of the rejuvenator in the aged asphalt was also analyzed using the Fourier transform infrared spectroscopy(FTIR),scanning electron microscope(SEM)and chemical composition tests.The research results showed that the optimum rejuvenator content was about 3%.Higher temperature and longer time were beneficial to improving the permeability and diffusion of the rejuvenator.During the aging process,the light components were reduced,and more macromolecular asphaltenes were generated as well as a large number of carbonyl and sulfoxide.After diffusion and regeneration,the light components in the asphalt were supplemented,the wrinkles and gullies of the aged asphalt were almost improved to the surface state of the matrix asphalt.

Utilization of Waste Cooking Oil as Diesel Fuel and Improvement in Combustion and Emission

Due to high price of Straight Vegetable Oil （SVO） for bio-diesel production, the use of Waste Cooking Oil （WCO） will be cost effective. Furthermore, utilization of WCO will refrain waterways pollution and endanger ecosystem. In Malaysia, more than 50-tone of WCO from various sources was produced every day. This study evaluates combustion performance and exhaust emission characteristics of several WCOs with different sources. Modification on fuel properties has been done to improve the combustion and exhaust emission of using WCO as diesel fuel. Regular diesel fuel also has been used for comparison in the test. A 0.6 liter, single-cylinder, air-cooled direct injection diesel engine was used to perform this experiment. Experiment was done at variable engine loads at constant speed.

基于性能演变的富油胶粉再生剂-老化沥青融合行为分析

富油胶粉(ORR)再生剂是由餐饮废油(CWO)与胶粉(RP)在一定的工艺下共混制备的环保型生物再生剂,其综合利用了CWO和RP的优势,有助于实现老化沥青再生过程中的高低温性能均衡.然而,油胶两相的特征导致ORR再生剂与老化沥青的融合行为较为复杂,不利于洞察ORR再生剂的应用潜力.本研究设计了再生剂-老化沥青融合试验,依据不同取样深度老化沥青样品的性能演变分析了温度和时间影响下ORR再生剂-老化沥青的融合效率及特征,并通过红外光谱检测技术进行了验证.同时,对比了ORR再生剂和CWO与老化沥青融合行为的差异,以期更加明晰地展现ORR再生剂-老化沥青的融合特征.结果表明,升高温度及延长时间有利于ORR再生剂-老化沥青的融合.与130℃融合温度相比,在150℃融合温度下延长融合时间更有利于ORR再生剂与老化沥青的融合.此外,130℃的融合温度下,ORR再生剂中降解RP成分进入老化沥青滞后于CWO成分.但在150℃的融合温度下,降解RP成分进入老化沥青滞后于CWO成分的现象并不明显.整体来说,ORR再生剂与老化沥青的融合效率不及CWO,但两者的差异并不显著.建议在150℃以上拌合ORR再生剂与沥青混合料回收料(RAP),以确保ORR再生剂尽可能充分发挥再生作用.研究成果可以促进ORR再生剂的工程应用,研究方法也可以为类似研究提供参考.

餐厨废大豆油改性沥青性能研究

公路建设消耗大量的石油资源,给节约资源、保护环境带来一定的压力。生物沥青的研发一方面促进了生物质资源的再生利用,另一方面直接或间接减少了石油沥青的开采。以餐厨废大豆油为添加剂,制备了废大豆油改性沥青。通过针入度、软化点和黏度等常规性能试验以及多重应力蠕变与恢复试验(MSCR)、线性振幅扫描试验(LAS)等流变性能探究了废大豆油对基质沥青路用性能的影响。结果表明:由于废大豆油自身轻质组分多、黏度小等物化特征,废大豆油提高了沥青的针入度,降低了沥青的软化点及黏度,并且废豆油掺量越多,这种改性效果越明显。掺入6%的废豆油能使70^(#)和90^(#)基质沥青的针入度分别提高93.2%和68.6%,使软化点分别降低7.9℃和4.9℃,使黏度分别降低31.3%和22.9%。黏度的降低改善了沥青的施工和易性,6%掺量的废豆油可使70^(#)和90^(#)沥青的拌合温度降低9.4℃和6.6℃,压实温度降低10.8℃和8.2℃。此外,废大豆油增加了沥青的不可恢复蠕变柔量,降低了变形恢复率。因此,废豆油使沥青黏性成分增加,抗高温蠕变性能降低,但增加了重复荷载下沥青的疲劳寿命。实际应用中,废豆油掺量可根据地区温度差异进行调整,应在不过多损害高温性能的同时提高低温性能或施工简易性。

一种废机油型乳化炸药水相配方的研究与应用

在研究废机油资源化应用的基础上,对国外某特大型矿山使用的乳化炸药的成本进行优化,制备了以少量氯化钠代替硝酸钠作为水相添加剂的废机油型乳化炸药,并对其水相析晶点、储存期、泵送次数、抗颠簸性能、爆速及爆后岩石块度进行基础性试验研究。结果表明:添加氯化钠可以降低水相析晶点10℃左右;制备的乳化炸药储存稳定性良好,满足多次泵送和长距离运输的需求;爆速可以到达4600 m/s以上;殉爆距离为14 cm。虽性能略有降低,但不影响正常使用,爆破后的岩石块度符合矿山铲运要求。相比原有配方,废机油型乳化炸药的成本可以节约49.59美元/t,具有一定的实用价值和经济效益。

基于分子动力学的废植物油再生沥青扩散行为研究

为研究不同废植物油掺配量、扩散温度及时间对废植物油与老化沥青相互扩散行为的影响,提出了考虑沥青老化程度随沥青膜深度变化的三层分子扩散模型,并结合傅里叶红外光谱(FTIR)测试及宏观尺度的软化点试验,分析废植物油再生剂与老化沥青之间的相互扩散行为。结果表明:废植物油再生剂通过补充老化沥青中的轻质组分、减少沥青质的团聚从而实现老化沥青的再生。温度的升高、废植物油掺量及扩散时间的增加均会增强废植物油与老化沥青的相互扩散效率,其中温度的影响最为显著;但随着温度增高,其对于扩散效率的增幅程度降低。皮尔逊相关性分析结果显示,模拟与宏观之间扩散系数相关性显著,三层分子扩散模型能够有效表征再生剂与老化沥青的相互扩散行为。

废植物油再生沥青流变性能研究

为有效提升废植物油的再生利用效率,研发出基于废植物油生产的再生剂,以便实现对沥青的再生利用。针对老化沥青在不同废植物油再生剂作用下的特性,包括闪点、质量损失、针入度、软化点、延度、黏度,高低温稳定性、频率特性等流变性能指标,构建植物油基础油(代号YJ)掺量与其再生沥青物理指标、流变性能指标之间的对应函数。研究发现,老化沥青的针入度受生催化剂影响,后者的加入提高了针入度,再生沥青针入度与YJ掺量之间有着较好的线性关系。加入再生剂后,软化点降低,二者呈线性关系,且掺量越高,改善越明显。随着YJ掺量的增加,再生沥青的初始模量不断降低。当YJ掺量为10%时,老化沥青含再生剂时,可显著改善老化沥青在低温条件下的抗塑性变形能力,使再生沥青逐渐达到与原样沥青同等的初始模量水平。在YJ掺量5%时,可恢复老化沥青疲劳性能至原样沥青水平。老化沥青的低温抗裂能力随着植物油再生剂的加入而有所提高,抗裂效果与YJ掺量是正相关的。研究进一步表明,植物油再生剂不利于老化沥青的抗变形能力。

试验室发动机废机油回收技术研究

发动机试验过程中要对废旧机油进行回收,保障试验的有效、合规开展,但现有的人力方式大大降低试验效率,文章开展试验室发动机废机油回收技术研究。文章首先剖析了现有发动机人力回收的问题所在;然后,提出可移动式废旧发动机机油回收小车设计方案,并按照设计原理打造出实物;最后,通过实践应用进行效益分析,验证了设计方案的可行性,提升了试验室发动机试验的效率,为国内外试验室发动机废机油回收提供技术参考。

废旧塑料/植物油复合再生沥青流变性能研究

为研究废旧塑料(PE)与植物油(Plant oil,PO)复合再生沥青流变性能,选用70#A级沥青作为基质沥青,采取室内老化的方式制备老化沥青,并通过正交试验获取废塑料、植物油最佳的掺量水平以及最佳制备温度,开展复合再生沥青流变性能研究。试验结果表明:植物油掺量6%、PE掺量6%、制备温度160℃时,复合再生沥青的三大指标较优;植物油掺入老化沥青后显著改善老化沥青的低温性能,降低老化沥青的黏度,但相比基质沥青高温性能有明显降低;而经过废塑料复合改性再生后,提高了植物油再生沥青的高温性能,增加了植物油再生沥青的黏性,同时对再生沥青的低温性能也有增益作用。复合再生沥青的高温性能、疲劳性能、低温性能明显优于植物油再生沥青。

废弃机油残留物对不同沥青高温性能的影响和改性机理

为了探究废弃机油残留物(WEOB)对不同沥青的改性效果和指标性能,选取基质沥青和SBS改性沥青进行了试验,对2种不同沥青胶结料进行了WEOB改性,研究改性沥青的高温性能和改性机理。分析比较了不同WEOB掺量下沥青改性前后的高温性能,结合相应试验结果,对改性机理进行了深入分析。首先,采用气相色谱-质谱联用(GC-MS)试验分析了WEOB中的化学组分。其次,利用软化点、旋转黏度(RV)、温度扫描(TS)和频率扫描(FS)评价了WEOB改性沥青的高温性能。最后,借助傅里叶红外变换光谱(FTIR)的化学官能团分析和荧光显微镜微观形貌观测揭示了WEOB改性沥青机理。结果表明:WEOB中的轻组分对基质沥青和改性SBS沥青的高温性能有重要影响,轻组分有助于更多沥青质的溶解,软化了基质沥青,WEOB中轻质组分改变了基质沥青的组分含量,使沥青的弹性性能下降,使其丧失了部分高温性能,而SBS在WEOB提供的富余轻质组分环境中继续发生溶胀吸附,增强了聚合物相网状结构,使沥青分子的热运动受到更有效的限制;基质沥青改性前后未出现新的特征吸收峰,因此该改性过程属于物理变化,SBS沥青改性后,出现了马来酸酐(MAH)的特征峰,生成了SBS接枝MAH的三元体枝接产物(SBS-g-MAH),提高了沥青与SBS之间的相容性,增强了其高温抗变形能力。

改性废机油常温浮选磷灰石矿的试验研究

为减轻废机油对环境的污染,以废机油为基础,经氧化改性制得新型捕收剂,并考察了其在低品位磷灰石矿浮选中的应用情况。以重铬酸钾为氧化剂,在通气量为0.15 m^(3)/h、氧化时间为24 h、氧化温度为110℃、重铬酸钾用量为废机油质量的0.2%时,获得最佳的氧化效果。红外光谱和气质联用分析结果表明,经氧化改性后,废机油中的C=C双键部分被氧化为羟基和羧基等官能团,属于脂肪酸类捕收剂。实际矿石分选结果表明,针对P_(2)O_(5)品位为1.72%的某磷灰石矿,在矿浆温度为15℃的条件下,当水玻璃用量2000 g/t、改性废机油捕收剂用量400 g/t时取得较好的分选效果,经一次粗选可获得精矿P_(2)O_(5)品位为26.01%、精矿回收率为95.12%的磷灰石精矿,并且在15~40℃温度范围内,浮选效果基本一致。经氧化改性的废机油可作为磷灰石潜在的浮选捕收剂。

废机油再生SBS改性沥青性能及再生机理

为研究废机油对老化苯乙烯-丁二烯-苯乙烯嵌段共聚物(styrence-butadiene-styrene,SBS)改性沥青的再生效果及再生机理。采用沥青加速老化试验模拟长期老化过程制备老化SBS改性沥青,分别添加不同含量的废机油制备再生沥青,并结合沥青物理性能、流变性能试验评价再生SBS改性沥青性能。在此基础上,采用红外光谱试验、4组分分析试验、荧光显微分析试验探究废机油再生SBS改性沥青机理。研究结果表明:老化后SBS改性沥青针入度与延度降低,软化点与黏度增加,废机油的掺入将会增加老化SBS改性沥青针入度与延度,降低软化点与黏度,且与废机油掺量成正比;废机油的使用将会降低再生SBS改性沥青的高温流变性能,提高再生SBS改性沥青的疲劳寿命;废机油能够降低老化SBS改性沥青劲度模量,对蠕变速率指标影响不显著;SBS改性沥青在老化过程中SBS发生破坏,沥青中的羰基与亚砜基含量增加,而废机油的掺入将会降低老化沥青中羰基与亚砜基含量,属于物理再生过程;SBS改性沥青老化后,饱和分、芳香分含量减少,胶质、沥青质含量增加,而废机油掺入后影响则反之;废机油的掺加将会使断裂的SBS分子部分溶胀,恢复沥青性能。

不同废油对老化SBS沥青流变性能的影响

为了探究不同废油对长期老化后SBS沥青流变性能和微观结构的影响,选用厨余油、废生物油、废机油作为再生剂掺入老化SBS沥青中。通过动态剪切流变仪进行了温度扫描、频率扫描、多应力重复蠕变(MSCR)试验、线性振幅扫描(LAS)、弯曲梁蠕变(BBR)试验,对全温度域内再生沥青的流变性能进行了综合评价。采用四组分分析试验与荧光显微镜对不同废油再生SBS沥青的化学组成和微观结构进行了观测,分析了不同废油的再生机理。结果表明:不同废油均能够补充沥青在老化过程中损失的轻质组分,软化沥青,降低沥青硬度与脆性,使得再生沥青高温流变性能和弹性恢复性能低于老化后沥青,且废机油对于老化沥青高温性能的影响最小;不同废油可提升再生沥青的抗疲劳性能,厨余油再生沥青疲劳寿命相比老化沥青提升了110%以上,废生物油与废机油再生沥青的疲劳寿命也高于老化沥青;3种废油再生沥青的低温抗裂性能均有不同程度的恢复,在降低劲度模量的同时蠕变速率增大,废生物油对老化沥青低温性能恢复效果最好,劲度模量相比老化沥青降低了40%;不同废油的再生机理类似,即能够补充老化沥青因热氧作用损失的轻质组分,调节老化沥青的化学组分,改变沥青的胶体结构;废油的加入对老化SBS沥青中降解的聚合物没有明显影响,不能修复断裂的SBS分子。

废机油改性乳化沥青冷再生混合料疲劳性能

为改善冷再生沥青混合料(cold recycled asphalt mixture,CRAM)的耐久性能,提出将废机油改性乳化沥青应用于CRAM。在探究废机油改性乳化沥青冷再生混合料(waste engine oil modified cold recycled emulsified asphalt mixture,WEO-CRAM)力学性能和路用性能的基础上,采用间接拉伸疲劳试验研究了WEO-CRAM的疲劳寿命,并应用Weibull分布对疲劳试验结果进行分析,建立了疲劳方程。结果表明:CRAM冷再生沥青混合料的劈裂强度随废机油掺量的增加逐渐增加,不同再生沥青路面(recycled asphalt pavement,RAP)掺量的混合料均对应一个最佳废机油再生剂掺量。与普通CRAM相比,WEO-CRAM的抗裂性能至少提高了13%,且废机油对混合料的高温性能和水稳定性影响不大。基于Weibull分布建立的疲劳方程可以有效地评估WEO-CRAM的疲劳寿命。在不同应力比下,WEO-CRAM具有良好的抗应力变化敏感性和抗疲劳破坏能力,在应力比为0.45时的疲劳寿命较CRAM提高了35%。

Emissions of intermediate volatility organic compound from waste cooking oil biodiesel and marine gas oil on a ship auxiliary engine

Ship auxiliary engines contribute large amounts of air pollutants when at berth.Biodiesel,including that from waste cooking oil(WCO),can favor a reduction in the emission of primary pollutant when used with internal combustion engines.This study investigated the emissions of gaseous intermediate-volatile organic compounds(IVOCs)between WCO biodiesel and marine gas oil(MGO)to further understand the differences in secondary organic aerosol(SOA)production of exhausts.Results revealed that WCO exhaust exhibited similar IVOC composition and volatility distribution to MGO exhaust,despite the differences between fuel contents.While WCO biodiesel could reduce IVOC emissions by 50%as compared to MGO,and thus reduced the SOA production from IVOCs.The compositions and volatility distributions of exhaust IVOCs varied to those of their fuels,implying that fuel-component-based SOA predicting model should be used with more cautions when assessing SOA production of WCO and MGO exhausts.WCO biodiesel is a cleaner fuel comparing to conventional MGO on ship auxiliary engines with regard to the reductions in gaseous IVOC emissions and corresponding SOA productions.Although the tests were conducted on test bench,the results could be considered as representative due to the widely applications of the test engine and MGO fuel on real-world ships.

胶粉/废机油复合改性沥青的制备及高温流变性能优化

研究主要目的是将胶粉和废机油这两种汽车工业废料用于道路工程中,开发一种可持续环保的沥青胶结料。首先,采用中心组合设计方法进行试验设计,确定制备胶粉/废机油复合改性沥青制备参数;其次,开展旋转黏度、动态剪切流变试验、多重应力蠕变试验评价不同制备工艺条件下复合改性沥青高温流变性能。结果表明在胶粉改性沥青中掺入5%~10%废机油有利于增加胶粉改性沥青的流动性。采用中心组合设计方法确定的废机油掺量、拌合温度、拌合时间最佳参数分别为5%、160℃、20 min。与胶粉改性沥青相比,优化后复合改性沥青的黏度降低了27.1%,其流动性和可泵性提高。与基质沥青相比,优化后复合改性沥青的58℃未老化车辙因子和老化车辙因子均高出了约54%。