生物质合成气制备及合成液体燃料研究进展

主要介绍了国内外生物质气化制备合成气工艺以及国内外生物质合成气合成液体燃料的工艺技术.生物质直接气化技术在早期得到了较好的发展,但生物质收集困难,限制了其发展.近几年国内外开发了生物质两段气化工艺技术.该技术通过快速裂解把生物质裂解为能量密度相对较高的快速裂解油(生物油),通过收集生物油制备合成气路线可以降低整个系统的...     

生物油的精制及其研究进展

生物质是唯一可以转化为液体燃料的、对环境友好的、清洁的可再生资源。通过高压液化或热裂解方法可将生物质制备成类似石油的黏稠状物质-生物油。生物油的高含氧量、低热值和化学不稳定等特性在一定程度上影响了其广泛应用,因此必须对生物油进行精制,以改善生物油的品质。从催化加氢、催化裂解、催化酯化、烯烃改性等方面阐述了生物油的精制技术及其研究进展。     

木质生物质在不同溶剂作用下的液化反应研究进展

生物质液化技术可将低品位的固体生物质转化成高品位的液体燃料或化学品,是生物质高效利用的主要方式。首先分析了不同生物质组分液化过程中的机理,在此基础上,以木质生物质液化溶剂的选择为出发点,讨论了水、醇类以及混合溶剂作用下的液化反应,同时比较了催化剂对液化过程及产品组成的影响,指出醇类溶剂液化在液化油产品质量、液化过程分子结构的调控方面具有较大的优势,在高品质液化油、燃油添加剂合成等方面具有较高的应用前景。     

生物质能源转化技术与应用(Ⅲ)——生物质热解液体燃料油制备和精制技术

生物质能源是唯一可再生、可替代化石能源转化成气态、液态和固态燃料以及其它化工原料或者产品的碳资源。随着化石资源的枯竭和人类对全球性环境问题的关注,生物质能源替代化石能源利用的研究和开发,已成为国内外众多学者研究和关注的热点。本系列讲座主要讲述以生物质资源为主要原料,通过不同途径转化为洁净的、高品位的气体、液体或固体燃料。本讲主要综述了生物质高压液化、快速热解液化制备液体燃料油技术现状、工艺及设备,并在总结生物质热解液体燃料油特性的基础上,总结了生物热解液体燃料油的物理法精制技术(包括脱水、添加溶剂和乳化)和化学法精制技术(包括催化加氢、催化裂解、催化酯化、水蒸气重整)的研究现状,并对其精制机理、优缺点进行了分析。随着制备和精制技术的深入研究,生物质热解液体燃料油可望替代汽油、柴油等化石燃料而越来越受到人们的关注。     

生物质快速裂解液化技术的研究进展

综述了生物质能转化的技术途径,生物质热裂解的４种方式,着重介绍了生物质快速裂解直接液化的各种著名工艺和生物质燃料油的特点及其开发和利用。指出了目前生物质裂解技术以及生物质油深加工的难点和发展方向。     

生物质制备生物油裂解反应器研究进展

生物质热裂解是生物质在隔绝空气的条件下,快速加热裂解,裂解蒸汽经快速冷却制得棕褐色液体产物。将生物质热解生成生物油,不仅便于运输和储存,而且还可以作为生产化工产品的原料。主要介绍了国内外生物质纤维素裂解制备生物油工艺、裂解反应器的特点等。就我国目前的技术,建议开发高效裂解工艺、新型高效反应器、研究反应机理以及开发高效催化剂等,从而降低生物质裂解油成本。     

生物质快速热解液化技术的研究进展

本文论述了生物质热解关键技术和热解制备生物油的工艺原理,同时综述了国内外快速热解反应器的现状.重点分析了传统的生物质快速热解关键技术--加料技术、气--固快速分离技术及反应温度、升温速率等因数的影响,提出了目前生物质热裂解液化技术的难点和液化燃料油的利用和开发技术的发展方向.     

生物质液化及提质改性研究进展

综述了近年来国内外生物质热化学转化技术的研究状况。介绍了生物质液化技术现状及生物质油精制提炼方法,包括苯酚液化、多元醇液化、弗托合成、催化加氢、催化裂解、催化酯化等。指出了现存问题和未来发展方向。     

生物质油加氢脱氧精制研究进展

随着石油能源渐趋匮乏,生物质高温裂解制备生物质油备受关注。而生物质油中氧含量高达40%,这将影响生物质油的稳定性、极性、热值、粘度和酸性等,应必须对其进行加氢脱氧精制处理。文中介绍了裂解生物质油的组成分布和特点,阐述了裂解生物质油加氢脱氧精制的反应过程和影响因素。     

生物质油加氢脱氧精制研究进展

随着石油能源渐趋匮乏,生物质高温裂解制备生物质油备受关注。而生物质油中氧含量高达40%,这将影响生物质油的稳定性、极性、热值、粘度和酸性等,应必须对其进行加氢脱氧精制处理。文中介绍了裂解生物质油的组成分布和特点,阐述了裂解生物质油加氢脱氧精制的反应过程和影响因素。     

生物质高压液化制生物原油研究进展

介绍了生物质液化过程的最新研究进展;分析了原料种类、溶剂、催化剂、反应温度、反应压力、反应时间、反应器类型对高压液化过程以及产品组成和收率的影响;对生物质液化的机理进行了剖析;对生物质液化制生物原油过程进行了展望,认为降低生物原油的生产成本、降低生物原油中的氧含量是生物质液化的发展方向。     

Detailed CFD modelling of fast pyrolysis of different biomass types in fluidized bed reactors

In the present study, an Eulerian‐Eulerian computational fluid dynamics (CFD) model, combined with a comprehensive biomass reaction scheme, was used to simulate fast pyrolysis of four different biomass types in the fluidized bed reactors. The study focuses on the influence of biomass components of different biomass types on the yields, formations, and contents of compositions of pyrolysis products. The result showed that the bio‐oil yield of cellulose‐rich biomass was higher than other biomass types, and char was mainly produced by the fast pyrolysis of LIG‐C of biomass. Moreover, the contents of bio‐oil components were affected by the fast pyrolysis of biomass components. Further, the energy recovery coefficient (ERC) of bio‐oil obtained from pyrolysis of different biomass types was also calculated and analyzed in this paper.

     

Bio‐oil from whole‐tree feedstock in resol‐type phenolic resins

Renewable chemicals are of growing importance in terms of opportunities for environmental concerns over fossil‐based chemicals. Lignocellulosic biomass can be converted into energy and chemicals via thermal and biological processes. Among all the transformation processes available, fast pyrolysis is the only one to produce a high yield of a liquid‐phase product called bio‐oil or pyrolysis oil. Bio‐oil is considered to be a promising substitute for phenol in phenol formaldehyde (PF) resin synthesis. In this work, bio‐based phenolic resins have been formulated, partially substituting phenol by bio‐oils from two Canadian whole‐tree species. The new resins are produced by replacing 25, 50, and 75% of phenol with bio‐oil for each species (three bioresins per species). The aim of this study is to synthesize renewable resins with competitive price and satisfactory quality. The results obtained have shown that substitution degree up to 50% provided reactivity and performance equal or superior to the pure PF resin. They also present a good storage stability, improved shear strength, and thermal stability comparable to the pure PF. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 40014.     

Direct catalytic upgrading of biomass pyrolysis vapors by a dual function Ru/TiO2 catalyst

The results of catalytic treatment of vapors exiting a g/min pyrolysis unit before product condensation to the liquid phase using a Ru/TiO₂ catalyst for oak and switchgrass pyrolysis are reported. The pyrolysis is conducted at 500°C and the catalysis at 400°C at atmospheric pressure with a hydrogen partial pressure of 0.58 atm. It is found that the catalytic treatment provides significant conversion of light oxygenates to larger, less oxygenated, molecules and, simultaneously, bio‐oil phenolics are also converted to less oxygenated phenolics with methoxy methyl groups transferred to the ring. The activity of the catalyst gradually diminished with increasing biomass fed to the system. Untreated pyrolysis oil forms a single liquid phase with some tarry material, consistent with the literature, whereas the treated liquid product forms separate oil and aqueous phases, the latter of which is about 80% water. The oil from the treated vapors has a lower initial viscosity with only a small increase upon accelerated aging compared to the untreated product oil, which has a dramatic increase in viscosity after aging. This is indicative of poor oil stability for untreated oil that is further confirmed by large increases in molecular weight, while the treated oil has a small increase in molecular weight after accelerated aging. In an effort to understand compatibility with refinery streams, the solubility of the oils in tetralin was examined. The untreated oil was found to have very limited solubility in tetralin, whereas the treated oil phase was completely soluble except for a small aqueous phase that appeared. There are a number of challenges in developing a high yield process for pyrolysis based conversion of biomass to transportation fuels. The Ru/TiO₂ catalyst used here shows promise for conducting multiple types of favorable reactions in the presence of the full spectrum of primary pyrolysis products that creates significant product stability under mild conditions. This could lead to higher liquid yields of stable, refinery compatible, product oil. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2275–2285, 2013     

The continuous flash pyrolysis of biomass

A continuous atmospheric pressure flash pyrolysis process for the production of organic liquids from cellulosic biomass has been demonstrated at a scale of 1–3 kg/hr of dry feed. Organic liquid yields as high as 65–70% of the dry feed can be obtained from hardwood waste material, and 45–50% from wheat straw. The fluidized sand bed pyrolysis reactor operates on a unique principle so that char does not accumulate in the bed and treatment of the sand is not necessary. The product gas, about 15% of the yield, has a medium heating value. The liquid product is an acidic fluid, which pours easily and appears to be stable. A preliminary economic analysis suggests that if the pyrolysis oil can be used directly as a fuel, its production cost from wood waste is probably competitive with conventional fuel oil at the present time.     

生物质热解液化制备生物油技术研究进展

介绍了国内外生物质热解液化工艺、主要反应器及其应用现状;简述了生物质催化热解、生物质与煤共热解液化、微波生物质热解、热等离子体生物质热解几种新型热解工艺;并对目前生物质热解动力学研究进行了总结;对未来生物质热解液化技术的研究进行了展望。     

我国非木质植物原料热解及液化研究进展

综述了几类非木质植物原料热解及液化的研究进展,介绍了液化方法及影响液化产物得率和质量的因素,同时对液化产物的表征方法、性质和应用范围作了简单的论述,并介绍了世界上几种流行的热解工艺,最后指出了开展非木质植物原料热解及液化的基础研究工作具有现实的意义。