Optimization of process for the production of bio-oil from eucalyptus wood

The pyrolysis of eucalyptus wood was carried out in a batch reactor to optimize the yield of bio-oil.Effect of various parameters like feed(particle) size,temperature,presence of catalyst and heating rate on the yield of bio-oil was investigated.The optimum conditions for high yield of bio-oil are for the particle size 2 mm~5 mm(average l/d=12.84/2.03 mm) at 450 ℃ in high heating rate.The reaction kinetics and the quality of bio-oil produced are independent of the presence of different catalysts like mordenite,kaoline clay,fly ash and silica alumina.The physical properties like odour,colour,PH,viscosity,heating value were determined.The FT-IR analysis of bio-oil indicates the presence of different functional groups such as monomeric alcohol,phenol,ketones,aldehydes,carboxylic acid,amines,and nitro compounds.The composition of the bio-oil at different conditions was analyzed using GC-MS and found that the components are temperature dependent but independent of catalysts used.     

微波条件下固体酸催化剂催化酯化生物油的研究

以乙醇和乙酸的酯化作为反应模型,考察固体酸催化剂阳离子交换树脂、SO₄²-/ZrO₂和分子筛在微波加热条件下的酯化活性。结果表明,三类固体酸催化剂的活性顺序为Amberlite树脂﹥SO₄²-/ZrO₂﹥HZSM-5,催化剂活性与酸度一致;酯化反应中水的含量对催化剂的活性有不同程度的影响,水含量较高时催化剂SO₄²-/ZrO₂酯化活性明显变差,而阳离子交换树脂仍具有较高的酯化活性。采用阳离子交换树脂对生物油进行微波催化酯化提质后,原生物油中含有的大量不同种类的羧酸被有效地转化成各种酯类,酯类化合物由原油中的4种增加到13种。与传统加热条件下生物油催化提质比较,生物油微波提质具有明显优势,提质后生物油组分得到优化。     

Application of thermal analysis for evaluating the digestion of microwave pre-treated sewage sludge

The effect of microwave pre-treatment (MwP) on anaerobic digestion of sewage sludge was studied by means of thermal analysis and evolved gas analysis. The effect of the pre-treatment at low energy input (<1000 kJ L^?1) on sludge solubilisation was studied with the aid of response surface methodology. The pre-treatment process was subsequently studied at energies of 488–2700 kJ L^?1 to evaluate the improvement in biogas production under mesophilic conditions. Organic matter modifications were studied using a Setaram TGA92 analyser at atmospheric pressure coupled to an MSC200 quadrupole mass spectrometer from Balzers. Particle size analysis was carried out using a Laser Diffraction Particle Size Analyser LS 13 320 Beckmann Coulter for evaluating the effect of MwP on sludge particles. Results showed an increase in organic matter solubilisation with the increase in the energy applied. Modifications in the specific surface area of the organic matter due to the MwP resulted in increments in methane yields. However, an accumulation of complex compounds was observed in thermal profiles at the maximum energy input (2700 kJ L^?1). Semi-continuous digestion experiments were evaluated using as substrate pre-treated sludge at the optimum energy value (975 kJ L^?1). Results showed a significant increase in methane yield (43 %) when evaluating the process at hydraulic retention times (HRTs) of 25–10 days.     

Pyrolysis characteristics and kinetics of sewage sludge for different sizes and heating rates

The pyrolysis characteristics and kinetics of sewage sludge for different sizes (d < 0.25 mm, 0.25 mm < d < 0.83 mm, and d > 0.83 mm) and heating rates (5, 20, and 35 °C/min) were investigated in this article. The STA 409 was utilized for the sewage sludge thermogravimetric analysis. FTIR analysis was employed to study the functional groups and intermediates during the process of pyrolysis. Meanwhile, a new method was developed to calculate pyrolysis kinetic parameters (activated energy E, the frequency factor A, and reaction order n) with surface fitting tool in software MATLAB. The results show that all the TG curves are divided into three stages: evaporation temperature range (180–220 °C), main decomposition temperature range (220–650 °C), and final decomposition temperature range (650–780 °C). The sewage sludge of d < 0.25 mm obtains the largest total mass loss, especially at the heating rate of 5 °C/min. By FTIR analysis, the functional groups including NH, C–H, C=C, etc., are all found in the sewage sludge. There is a comparison between the FTIR spectra of sludge heated to 350 °C (temperature associated to maximum devolatilization rate in the second stage) and the FTIR spectra of sludge heated to 730 °C (temperature associated to maximum devolatilization rate in the third stage). In the second stage, the alcohols, ammonia, and carboxylic acid in the sludge have been mostly decomposed into gases, and only a little bit of compounds containing CH and OH of COOH exist. The pyrolysis kinetic parameters of second stage are as follows: the reaction orders are in the range of 1.6–1.8 and the activation energy is about 45 kJ/mol. The frequency factor increases with the increase of heating rate and sewage sludge size.     

Sustainability of biodiesel production in Malaysia by production of bio-oil from crude glycerol using microwave pyrolysis: a review

Biodiesel being one of the most promising renewable biofuels has seen rapid increase in production capacity due to high demand for diesel replacement; along with oversupply of its by-product, crude glycerol. Developing new industrial usage for glycerol is essential to defray the cost and sustainability of biodiesel industry and to promote the biodiesel industrialization. One of the approaches is by the transformation of glycerol into a liquid, referred as bio-oil through pyrolysis technology. Bio-oils produced by pyrolysis processes can be upgraded to produce transportation fuels or for power generation. However, current state of pyrolysis technologies are still major hurdles their development with respect to its commercial applications. Recently, microwave technology has attracted considerable attention as effective method for significantly reducing reaction time, improving the yields and selectivity of target products. Hence, this review strives extensively towards addressing the application of microwave-assisted technology applied to the pyrolysis process as a way of cost-effective and operationally feasible processes to directly utilize crude glycerol. The present review will focus on the pyrolyzed liquid product (bio-oil) derived by employing the microwave-assisted pyrolysis method. This review concludes that microwave-assisted glycerol conversion technology is a promising option as an alternative method to conventional glycerol conversion technology.     

Thermal analysis of soil amended with sewage sludge and biochar from sewage sludge pyrolysis

The main objective of the present study is to study the behaviour of sewage sludge and biochar from sewage sludge pyrolysis after addition to soil in a context of a temperate agricultural soil. For this, an incubation experiment was designed during 200 days. Carbon mineralization of soil amended with sewage sludge and biochar at two different rates (4 and 8 wt%) was evaluated. Differential thermal analysis, thermogravimetry and the first derivate of the TG were performed in oxidizing conditions on soil samples before and after incubation. Biochar obtained from sewage sludge pyrolysis at 500 °C was more stable in soil than original sewage sludge. After incubation experiment, the reduction of soil organic matter content was significantly lower in soil amended with biochar than in soil amended with sewage sludge. The thermostability index WL₃/WL₂ decreases after incubation in soil amended with biochar, however it increases in case of soil treated with sewage sludge.     

Thermal characteristics of the combustion process of biomass and sewage sludge

The combustion of two kinds of biomass and sewage sludge was studied. The biomass fuels were wood biomass (pellets) and agriculture biomass (oat). The sewage sludge came from waste water treatment plant. The biomass and sludge percentage in blends with coal were 10 %. The studied materials were characterised in terms of their proximate and ultimate analysis and calorific value. The composition of the ash of the studied fuels was also carried out. The behaviour of studied fuels was investigated by thermogravimetric analysis (TG, DTG and DTA). The samples were heated from an ambient temperature up to 1,000 °C at a constant three rates: 10, 40 and 100 °C min^?1 in 40 mL min^?1 air flow. TG, DTG and DTA analysis showed differences between coal, biomass fuels and sewage sludge. 10 % addition of studied fuels to the mixture with coal changed its combustion profile in the case of sewage sludge addition. The combustion characteristics of fuel mixtures showed, respectively, qualitative summarise behaviour based on single fuels. Evolved gaseous products from the decomposition of studied samples were identified. This study showed that thermogravimetric analysis connected with mass spectrometry is useful techniques to investigate the combustion and co-combustion of biomass fuels, and sewage sludge, together with coal. Non-isothermal kinetic analysis was used to evaluate the Arrhenius activation energy and the pre-exponential factor. The kinetic parameters were calculated using Kissinger–Akahira–Sunose model.     

Evaluation on the non-isothermal combustion kinetics of lignite and sewage sludge through microwave pretreatment

Journal of Thermal Analysis and Calorimetry - Lignite and sewage sludge powder were pretreated through microwave heating at a power level of 119&nbsp;W. The non-isothermal combustion...     

污泥焚烧过程中Cd的迁移与转化特征

在一维固定燃烧炉上进行了污泥层燃模拟实验,重点研究了不同焚烧温度、停留时间、含水率及不同空气过剩系数条件下Cd的迁移和转化特征,并利用4种固体吸附剂CaO、Al2O3、粉煤灰和高岭土对污泥焚烧过程中Cd的排放进行吸附去除.研究结果表明,随着焚烧温度的升高,底渣中Cd有一定的挥发,并且焚烧底渣中Cd的可氧化态和易还原态会向残渣态转化,有利于降低焚烧底渣中Cd的生物可利用性.随着焚烧时间的延长,对焚烧过程中Cd的挥发影响不大,但可使焚烧底渣中Cd的易还原态和可氧化态向残渣态转化.焚烧过程中含水率对重金属Cd的残留率影响较大,当含水率达超过75%后,底渣中Cd残留率会明显降低,并且随着含水率的增加,底渣中Cd的可氧化态会向易还原态转化,而残渣态的比例变化不大.空气过剩系数在1~1.5之间时,焚烧底渣中Cd的含量、残留率及Cd可氧化态所占的比例变化不大,当从1.5升至2时,底渣中Cd的含量及残留率大幅度降低,并且底渣中Cd基本上以残渣态存在.污泥焚烧过程中4种固体吸附剂的加入有利于Cd的残留并固定在焚烧底渣中,并且随着固体吸附剂添加比例的增多,Cd的残留率也逐渐增加,吸附剂粉煤灰和高岭土要优于CaO和Al2O3.     

Heating process characteristics and kinetics of sewage sludge in different atmospheres

The treatment of wastewater generates a by-product, sewage sludge, the disposal of which poses problems. There are, however, a number of options for making use of this residue, including its conversion into a valuable fuel. The aim of this paper is to describe the process of the heating of sewage sludge under different atmospheres of helium and oxygen and to obtain the kinetic parameters by means of a mathematical model, a heating rate of 10 °C/min being used. Measurements were taken by thermogravimetry and mass spectrometry, and proximate and elementary analyses were made of the sludges and their calorific values were determined. Visual observation of the heating profiles shows four stages in the heating process, which have been characterized. The model proposed was found to adequately describe the weight loss of the sludges studied, while making it possible to obtain the kinetic parameters for the differentiated stages in the thermal process but not to establish any clear tendency of the evolution of these parameters with the increase in oxygen in the heating atmosphere.     

Hydrogen production from bio-oil by chemical looping reforming

Hydrogen is a green energy carrier. Chemical looping reforming of biomass and its derivatives is a promising way for hydrogen production. However, the removal of carbon dioxide is costly and inefficient with the traditional chemical absorption methods. The objective of this article is to find a new material with low energy consumption and high capacity for carbon dioxide storage. A metal organic framework (MOF) material (e.g., CuBTC) was prepared using the hydrothermal synthesis method. The synthesized material was characterized by X-ray diffraction, ?196 °C N₂ adsorption/desorption isotherms, and thermogravimetry analysis to obtain its physical properties. Then BET, t-plot, and density functional theory (DFT) methods were used to acquire its specific surface area and pore textural properties. Its carbon dioxide adsorption capacity was evaluated using a micromeritics ASAP 2000 instrument. The results show that the decomposition temperature of the synthesized CuBTC material is 300 °C. Besides, high CO₂ adsorption capacity (4 mmol g^?1) and low N₂ adsorption capacity were obtained at 0 °C and atmospheric pressure. These results indicate that the synthesized MOF material has a high efficiency for CO₂ separation. From this study, it is expected that this MOF material could be used in adsorption and separation of carbon dioxide in chemical looping reforming process for hydrogen production in the near future.     

Study of the pyrolysis liquids obtained from different sewage sludge

Pyrolysis of sewage sludge in fluidized bed to produce bio-oil is under study as a useful way to valorise this waste. Sewage sludge is the waste produced in the wastewater treatment plants. Its composition may change due to the origin and to the non-standardized treatments in the wastewater treatment plants. The pyrolysis of three samples of anaerobically digested sewage sludge obtained from three different urban wastewater treatment plants was studied in this work. The organic and inorganic matter composition, and the volatile and ash content of these sewage sludge samples were different. The influence of these parameters on the pyrolysis product distribution and on some characteristics of these products was studied. It was determined that the ash content of the raw material had an enormous influence on the sewage sludge pyrolysis. An increase in the ash content of the sewage sludge caused an increase in the gas yield and a decrease in the liquid and the solid yield with the operational conditions studied. The increase of the volatile content of the sewage sludge samples caused an increase in the liquid yield. The H₂ proportion was the most influenced non-condensable gas. It increased significantly with the ash content. The viscosity of the pyrolysis oils decreased when the ash content augmented. On the other hand, the water content depended on the organic composition of the sewage sludge samples. The chemical composition of the pyrolysis oils was also affected by the sewage sludge ash content above all the proportion of polyaromatic hydrocarbons and nitrogen-containing aromatic compounds. These compound groups increased with the augment of the sewage sludge ash content. The oxygen-containing aliphatic compounds and the steroids decreased with the ash content, although its proportion in the sewage sludge liquid was also influenced by the organic matter composition of the sewage sludge samples.     

蒸馏温度对核桃壳生物油馏分组分分布的影响

通过改变蒸馏温度对生物油进行常压蒸馏并将馏分分为油水两相，研究了馏分的组分分布变化。结果表明，在120-300℃随着蒸馏温度的升高，生物油馏出率不断增加；蒸馏温度低于240℃的油相馏分中萘、甲苯等芳烃类化合物和乙酸等羧酸类化合物明显富集，以120℃油相馏分为例，芳烃类和羧酸类化合物的相对含量是生物油原油的13.86倍和3.15倍；当蒸馏温度高于240℃时苯酚、愈创木酚等酚类化合物大量馏出，使得油相馏分的产率明显增加；同时，所获水相馏分中的水分含量皆高于60%，水分的富集效果明显；在馏分中检测到了2-乙基乙酸丁酯和环戊酮等原油中未检测到的组分并且馏分中水分总量高于生物油原油，这些都表明生物油在蒸馏过程中发生了酯化、缩聚等化学反应。通过对油相馏分的组分分布进行分析，发现改变蒸馏温度可以有效富集生物油中的高价值化合物，如苯酚、愈创木酚、4-甲基愈创木酚、4-乙基愈创木酚和4-丙基愈创木酚的相对含量在300℃的油相馏分中分别比生物油提高了109%、160%、84%、53%和444%。     

Studying the effect of microwave heating on the digestion process and identification of proteins

The impact of microwave irradiation on the in‐solution digestion processes and the detection limit of proteins are systematically studied. Kinetic processes of many peptides produced through the trypsin digestion of various proteins under microwave heating at 50°C were investigated with MALDI‐MS. This study also examines the detection limits and digestion completeness of individual proteins under microwave heating at 50°C and at different time intervals (1, 5 and 30 min) using LC‐MS. We conclude that if the peptides without missed cleavage dictate the detection limit, conventional digestion will lead to a better detection limit. The detection limit may not differ between the microwave and conventional heating if the peptides with missed cleavage sites and strong intensity are formed at the very early stage (i.e., less than 1 min) and are not further digested throughout the entire digestion process. The digestion of Escherichia coli lysate was compared under conventional and short time (microwave) conditions. The number of proteins identified under conventional heating exceeded that obtained from microwave heating over heating periods less than 5 min. The overall results show that the microwave‐assisted digestion is not complete. Although the sequence coverage might be better, the detection limit might be worse than that under conventional heating.     

Microwave-assisted reactions： Three-component process for the synthesis of 2-amino-2-chromenes under microwave heating

2-Amino-2-chromenes are class of heterocycles that posses considerable interest as pigments,cosmetics,potential agrochemicals and being the main constituents of many natural products.Although,they are generally prepared either under conventional heating,benign reagents or very recently,a three component condensation in poly-ethylene glycol-water in the presence of nanosized magnesium oxide,most of these methods require prolonged reaction time,reagents in stoichiometric amounts and generate moderate yield...     

Use of drinking water sludge in the production process of zeolites

This study reports the synthesis of zeolites A, X, and P, cancrinite, and sodalite using sludge generated in a drinking water plant. Two experimental steps were carried out: (1) fusion and (2) hydrothermal treatment. Crystallization was achieved by means of a 2³ experimental design with central point with the following factors: temperature, time, and solid/liquid ratio. The sludge presented Si and Al contents (SiO₂/Al₂O₃ = 1.7) which allow the synthesis of zeolites with high cation exchange capacity. The content of organic matter was considerable (loss on ignition 26.1 %), but is eliminated in the fusion step at 550 °C. This process also permits the conversion of the initial aluminosilicates into zeolite precursors (sludge–NaOH mix of 1:0.785 g/g). Hydrothermal treatment then permits the crystallization of the aforementioned zeolites. These materials showed high cation exchange capacities as compared to other commercial and experimentally synthesized zeolites, and can be used in the removal of heavy metals such Cd²⁺, Pb²⁺, Cu²⁺, Fe²⁺, and ammonium present in water, providing an interesting new option in wastewater treatment and remediation of soils.     

Correlation between heating values and thermogravimetric data of sewage sludge, herbaceous crops and wood samples

The thermal behaviours of a sewage sludge sample, woody (black locust, poplar and willow) and herbaceous (energy grass and wheat straw) biomass as well as mixed (sewage sludge and black locust in ratios 1:1 and 1:3) samples were compared under inert and oxidative atmosphere. The thermogravimetric experiments of each sample demonstrate that the beginning temperature of decomposition is similar in inert and oxidative atmospheres, i.e. the primary bond scissions are not affected by the atmosphere. Nevertheless, oxygen increases the decomposition rate and the volatile evolution of all samples at higher temperatures. Thermogravimetry/mass spectrometry (TG/MS) experiments have been performed to determine the mass loss of the samples and the formation of volatile products as a function of temperature in inert atmosphere. Wood and herbaceous biomass samples evolved various organic products (aldehydes, ketones, acids, furan derivatives, etc.) beside water and gaseous products. Sewage sludge released mainly water, carbon oxides, methane, hydrogen, hydrocarbons, ketones, acids as well as sulphur- and nitrogen-containing products. High heating value and low heating value of the samples have been determined by a bomb calorimeter. Principal component analysis (PCA) has been used to find statistical correlation between the data. The results unambiguously support the correlation between the thermogravimetric parameters (e.g. DTG_max) and the heating values of the samples.     

The kinetics of gasification of char derived from sewage sludge

Gasification of char derived from sewage sludge was studied under different oxidizing atmospheres containing CO₂, O₂ or H₂O. The gasification tests were carried out in thermobalance at different temperatures and oxidizing reagent concentrations. The most efficient were the gaseous mixtures containing oxygen. The reaction took place at temperature 400–500 °C, whilst in the case of CO₂ and steam much higher temperatures (700–900 °C) were necessary to complete the conversion. Two rate models for gas–solid reaction were applied to describe the effect of char conversion on reaction rate. The shrinking core model for reaction-controlled regime was found to be the best for predicting the rate of char gasification in CO₂ and O₂ atmosphere. The experimental data for steam gasification of the char were fitted best by the first-order kinetics. The kinetic parameters estimated from the experimental data are in accordance with the literature for lignocellulosic char gasification and are the first published for sewage sludge char gasification.     

离子液体作用下微波辐照生物质快速热解制备生物质油(英文)

以离子液体1-丁基-3-甲基咪唑氯([Bmim]Cl)和1-丁基-3甲基咪唑四氟化硼([Bmim]BF4)为催化剂,在微波加热作用下,研究了稻草和锯屑的热解。微波加热20 min,稻草和锯屑的生物油产率分别为38%和34%。考察了微波加热时间、微波功率和离子液体用量对生物质油产率的影响。当以相同的离子液体为催化剂时,稻草微波热解得到的生物质油产率大于锯屑的。生物油成分主要有糠醛、醋酸和1-羟基-2-丁酮等,其含量主要取决于生物质原料和加入的离子液体的类型。