木质纤维素类生物质热解转化研究进展

综述了木质纤维素类生物质热解技术的研究进展,总结了不同生物质原料的热解机理,分析了产物的组成和性质,研究了产物的调控、改性和应用.指出未来的研究方向应该集中在以下几方面:技术改进,致力于改进生物质热解技术,提高能源转化效率和产物选择性;产品多样化,除了生物质热解产生的主要能源产品,如生物炭、生物油和生物气,还应着眼于开发高价值的化学品和材料,包括生物基化学品、特殊化学品和高性能材料;集成系统,应尝试将生物质热解与其他能源转化技术相结合,形成多能源联供系统,与生物质发酵、光催化、电解和储能等技术集成,以提高整体能源系统的效率和可持续性.     

Production and Characterization of Bio-Chars from Biomass via Pyrolysis

This article deals with slow pyrolysis of oak wood and agricultural residues such as hazelnut shell and wheat straw at high temperature (950–1250 K) in a cylindrical reactor. The aim of this work is to study the effect of the treatment conditions such as temperature, particle size, and lignin and inorganic matter contents on bio-char yield and reactivity. When the pyrolysis temperature increased, the bio-char yield decreased. A high temperature and smaller particles increase the heating rate resulting in a decreased bio-char yield. The higher lignin content in hazelnut shell results in a higher bio-char yield in comparison with oak wood and wheat straw. Bio-chars from hazelnut shell and wheat straw are more reactive in gasification than bio-chars from oak wood because of the higher ash content. The bio-char obtained are carbon rich, with high heating value and relatively pollution-free potential solid biofuel.     

城市生活垃圾堆肥剩余物的燃烧特性及其焚烧处理

生活垃圾综合处理厂在堆肥过程中产生堆肥剩余物,占总垃圾量的10%～20%,热值较高适于焚烧处理.文章对城市生活垃圾堆肥剩余物的组成、工业分析及元素分析进行分析研究,表明该类堆肥剩余物具有热能回收利用价值.采用TGA方法研究垃圾堆肥剩余物的燃烧特性,结果表明,垃圾的燃烧过程包括水分析出、挥发分燃烧和焦炭燃烧三段进行.挥发分在320℃左右剧烈燃烧,焦炭在420～450℃左右开始强烈燃烧,燃尽温度达750℃左右.在实际流化床焚烧炉上焚烧结果表明,垃圾堆肥剩余物能够在800～950℃内稳定燃烧,并且NOx、SO2、CO、HCl以及重金属等污染物的排放浓度达到国家环保排放标准.为了减少焚烧飞灰量,建议采用炉排炉焚烧此类垃圾,以降低飞灰的处置成本.     

苇沟大型猪场猪粪沼渣在黄瓜栽培上的应用

用絮凝后的猪粪沼渣和沼水在黄瓜栽培上应用试验结果表明，用沼渣作基肥效稍优于等量Ｎ，Ｐ，Ｋ化肥，用沼水作追肥肥效明显低于等Ｎ化肥。沼渣中所含的Ｃａ，Ｆｅ，Ｃｕ，Ｍｇ，Ｍｎ，Ｚｎ，Ｍｏ等元素与黄瓜植株中所含的元素种类基本一致，长期应用沼渣可保持土壤肥力平衡，应用絮凝沼渣与化肥混合配成的复肥作基肥后，瓜中许多元素的含量低于其他处理，此现象可能与沼渣絮凝剂和加工工艺有关。     

利用沼气技术综合治理酒精厂废液

论述了年产万吨酒精厂用红薯干为主要生产原料,采用生物厌氧,兼氧消化,好氧,物化处理等技术,综合治理酒精糟液的先进工艺,实现了日处理浓度有机污水400－500t,COD,BOD,SS降解净化率均在99％以上,出水达到GB8978－1996规定的第二类污染物二级排放标准。全年生产沼气255万－270万m^3,可获直接经济效益260余万元人民币。     

沼渣底施对黄瓜生长及土壤微生物数量的影响

采用盆栽试验,研究了沼渣肥用量对黄瓜不同生育时期生长情况和土壤中细菌、真菌两种微生物数量的影响。结果表明,不同添加量的沼渣肥都能够显著促进黄瓜生长,其中以5.0%沼渣的综合应用效果最好,该处理对黄瓜收获期的根重、地上部重、植株干重、株高、叶数和茎粗分别比未施肥对照组高130.51%,141.87%,72.88%,26.70%,39.32%和35.11%。沼渣肥的施用也显著改变了土壤中微生物的数量,使土壤中细菌数量增加、真菌数量降低,对生育前期土壤微生物的数量影响很大,随着生育期的延长而逐渐降低。土壤中微生物含量与黄瓜生物量相关性分析表明,土壤细菌数与黄瓜生物量成正相关,土壤真菌数量与黄瓜生物量成负相关。田间试验表明,施用沼渣比常规处理产量增加8.3%,比空白对照增产19.2%。     

链霉素菌渣中温厌氧发酵产沼气性能研究

为实现链霉素菌渣的无害化、资源化利用,文章以链霉素菌渣为原料,在菌渣含固率为2%,温度为30±2℃的条件下进行60 d的厌氧发酵试验。试验结果表明:链霉素菌渣的累积产气量为18.20 L,中温产气能力为364.07 mL/g;在稳定产气阶段,发酵液的氨氮、VFAs含量均维持在较低水平,pH值大于7.0;厌氧发酵结束后,发酵液的VS去除率达64.32%;以金黄色葡萄球菌作为指示菌,在厌氧发酵后的沼液中未检测到链霉素残留。     

醋糟厌氧发酵特性的研究

以醋糟为厌氧发酵原料,分别进行了连续进料试验和全进全出料试验。连续进料试验结果表明,在每天进料量保持不变的情况下,日产气量稳定,平均产气率为0.918 m3/(m3.d),最高产气率可达1.111 m3/(m3.d)。经过计算可知,8.52 kg醋糟可产1 m3沼气。全进全出料发酵试验结果表明,醋糟厌氧发酵的体积上浮和膨胀非常明显。当进料浓度为4%时,料液最大膨胀体积为322.68 cm3,为发酵料液体积的28.8%。醋糟厌氧发酵具有降解速率快,滞留期短等特点。     

梨渣与猪粪混合厌氧消化产气试验研究

试验研究了梨渣和猪粪在分批厌氧发酵和连续厌氧发酵工艺中的产气性能.分批厌氧发酵考察不同接种量、渣粪比以及发酵温度对梨渣产气量和甲烷含量的影响,结果表明,接种量为30％和40％时发酵可以正常启动;梨渣中加入猪粪后产气性能提高,渣粪比为1:∶1时,甲烷含量在60％以上;高温条件下的总产气量比中温条件下高32％,但所产沼气中甲烷含量偏低.连续厌氧发酵试验表明,梨渣的添加比例从15％提高到50％时,干物质产气率从207 L/kg降低到109 L/kg,甲烷含量从81.2％降低到57.0％.     

电镀污泥焚烧后的灰渣分析

焚烧法是防止污泥中重金属污染的有效方法，电镀污泥焚烧处理后的灰渣中含有大量的重金属，需要对灰渣中的成分进行试验研究。对电镀污泥在管式炉内进行了不同焚烧温度和焚烧时间的试验后，将高温焚烧后的电镀污泥灰渣进行了X射线衍射（xRD）和能谱分析（EDX），得到了电镀污泥焚烧后的灰渣成分与焚烧温度和焚烧时间的关系。图5表1参8     

程序升温下秸秆类生物质燃料热解规律

用热重分析仪对秸秆类生物质的热解行为进行了热重分析（TG）和差分热分析（DTG）。试验中利用程序升温法对物料进行加热升温,加速率分别为10K/min,２０Ｋ／min和３０K/min;加热终温为1173K,样品料径为250－1000um,高纯氮气做保护气,通过对TC,DTG曲线分析,研究了加热速度,温度,加热时间等对热过程的影响,给出了热解反应动力学参数,结论对秸秆类生物的再利用技术研究和装置优化有重要的指导价值。     

玉米秸秆沼渣热裂解及热动力学研究

采用热重法(TG)-微分热重法(DTG)-差热分析法(DTA)研究玉米秸秆沼渣热解过程及热裂解反应动力学特征和机理。研究结果表明玉米秸秆沼渣的失重过程分为吸附水蒸发阶段和秸秆裂解、挥发性物质蒸发阶段。热解过程中,加热速率对玉米秸秆沼渣热解有显著作用。使用FWO、KAS和Popescu方法计算出其热解活化能分别为233、359、358 kJ/mol。对41种常用热裂解动力学机理函数分析确定其热裂解动力学机理为三级方程g(α)=(1-α)-2。扫描时电子显微镜(SEM)分析表明,热裂解可破坏玉米秸秆沼渣的木质纤维束状结构,降低木质纤维中的木质素和半纤维素的质量分数,但效果随升温速度的增大而变差。     

Oily Products from Mosses and Algae via Pyrolysis

In this study, the fuel properties of mosses and algae, and the effect of pyrolysis temperature on the yield of bio-oil from moss and alga samples, were investigated. The yield of bio-oil from pyrolysis of the samples increased with temperature. The yields were increased up to 750 K in order to reach the plateau values at 775 K. The maximum yields were 39.1, 34.3, 33.6, 37.0, 35.4, 48.2 and 55.3% of the sample for Polytrichum commune, Dicranum scoparium, Thuidium tamarascinum, Sphagnum palustre, Drepanocladus revolvens, Cladophora fracta and Chlorella protothecoides, respectively. The bio-oil yield for Chlorella protothecoides (a microalga sample) rose from 5.7 to 55.3% as the temperature rose from 525 to 775 K, and then gradually decreased to 51.8% and was obtained at 875 K with a heating rate of 10 K/s. Formulas can be developed to calculate higher heating value (HHV) of different moss and alga samples. The calculated HHV using these new correlations showed mean differences ranging from ?2.3% to +0.06%. The equation developed in this study showed good agreement with experimental results on moss and algae samples. The HHVs for bio-oils from mosses 21.5–24.8 MJ/kg and the HHVs for bio-oils from algae and microalga 32.5 and 39.7 MJ/kg, respectively, were obtained at temperature ranging from 775 to 825 K. In general, algae bio-oils are of higher quality than bio-oils from mosses. In general, microalgae bio-oils are higher quality than bio-oil from wood.     

沼渣热解动力学、热力学分析及热解产物特性研究

采用热重分析（TG）分析沼渣的热解特性,研究沼渣的热解动力学并计算指前因子A、焓变ΔH、吉布斯自由能ΔG、熵变ΔS等热力学参数。进一步考察温度对沼渣热解产物分布与性质的影响。其热解过程可分为3个失重阶段,其中第2阶段为主要失重阶段,采用Flynn-Wall-Ozawa（FWO）法、Friedman法和Kissinger-Akahira-Sunose（KAS）法计算的平均活化能分别为410.00、471.32和420.01 kJ/mol,热力学参数计算结果表明沼渣热解过程具有稳定的能量输出。沼渣热解油的产率随温度上升先增加后降低。气体产物的高位热值（HHV）从400 ℃时的6.82 MJ/Nm³增加到700 ℃时的8.54 MJ/Nm³。红外光谱（FTIR）、拉曼（Raman）光谱表明热解温度升高生物炭结构的有序性增加。     

秸秆气固燃料二元联产的可行性与经济性研究

以玉米秸秆和水稻秸秆为研究对象,通过测定二者厌氧发酵后的沼气、沼渣产量及热值,探讨秸秆气固燃料二元联产的综合能源利用效率与经济效益。结果表明,由于发酵后秸秆沼渣中木质素含量增大,沼渣热值也有所增大;沼渣成型燃料密度、机械耐久性等特性均优于原秸秆;秸秆气固燃料二元联产综合能源利用效率较秸秆直接燃烧可提高40%～50%(以发电量计);因免除收集、运输和粉碎等成本,秸秆沼渣生产成型燃料的综合成本较秸秆压块单独生产模式可节省46.4%。     

Producing Bio-oil from Olive Cake by Fast Pyrolysis

Abstract

This article reports on physico-chemical properties of olive cakes to evaluate them as a raw material in energy production through thermo-chemical pyrolysis conversion process. The present study focuses on the actions related to the possibilities to utilize in particularly olive cake as an agricultural residue. Olive cake is a very promising material for the production of bio-oil. Liquid, solid, and gaseous products were obtained from olive cake by pyrolysis. If the purpose were to maximize the yield of liquid products resulting from biomass pyrolysis, a low temperature, high heating rate, and short gas residence time process would be required. Flash pyrolysis gives high oil yields. The heating was carried out from 298 K to 1,050 K in the absence of oxygen. The yields of liquid products were obtained from the olive cake by pyrolysis for the runs of different heating rates: 10 K/s, 20 K/s, and 40 K/s. The highest bio-oil yields from the olive cakes were 31.0% at 700 K, 36.0% at 700 K, and 41.0% at 700 K obtained from 10 K/s, 20 K/s, and 40 K/s heating rate runs, respectively. The highest bio-oil yields olive stone shells were 27.0% at 700 K, 31.0% at 700 K, and 34.5% at 750 K obtained from 10 K/s, 20 K/s, and 40 K/s heating rate runs, respectively.     

生物油燃烧技术研究进展

生物油可以在锅炉中单独燃烧或者与化石燃料混合燃烧用于供热和发电,可以与乙醇、甲醇和柴油等混合燃烧以驱动柴油机发电,也可以直接应用于燃气轮机中.文章分析了由于生物油燃料特性的限制而引起的燃烧应用问题和相应的解决方法.分析表明,生物油与化石燃料在锅炉和燃气轮机中混合燃烧最具有大规模应用的可能性,在柴油机中燃烧是最有开发前景的应用技术.     

藻类异养转化制备生物油燃料技术

通过异养转化细胞工程技术获得了高脂肪含量的异养小球藻细胞,其脂类化合物含量高达细胞干重的55%,是自养藻细胞(14%)的4倍。利用这些高脂肪含量的异养藻快速热解获得高产量的生物油,产油率为57.9%(%藻干重),是自养藻细胞产油率(16.6%)的3.4倍。异养藻细胞的生物油热值高达41MJ/kg,分别是木材生物油和自养藻生物油的2倍和1.4倍。与木材或农作物秸秆的生物油和自养藻生物油相比,异养藻细胞的生物油具高热值(41MJ/kg)、低密度(0.92kg/l)、低粘度(0.02Pa·s)的特点。     

Bio-oils from arid land plants: Flash pyrolysis of Euphorbia characias bagasse

The devolatilization of the bagasse obtained by solvent extraction of dried Euphorbia characias, a bushy plant growing in arid land of the Mediterranean area, was investigated under rapid heating conditions at atmospheric pressure using a bench-scale fluidized bed pyrolyser. Particle heating rates exceeded 10⁴°C s⁻¹. Bagasse was fed continuously at the rate of 6 g h⁻¹ directly into a sand bed fluidized by nitrogen operating in the temperature range of 400°–750°C. The yields of oils, gases and chars are reported. A maximum oil yield of 44% (wt/wt) (moisture free bagasse) was obtained at 500°C. Yields of gases, CO, CO₂, C₁–C₄ hydrocarbons increased with the rise in temperature, reaching a maximum at 750°C. Elemental analyses showed that the composition of oils and chars was dependent on pyrolysis temperature. The nitrogen content is fairly high; an upgrading process could be necessary for its remotion before the use of the bio-oil as combustible. The other characteristics of oils fall in the range of oils derived from other biomass feedstocks. Chars have a high HHV (15.36 MJ kg⁻¹ at 500°C), representing a valuable fuel.