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11.
Photosynthetic suspension cultures of higher plants offer an alternative approach to biomass production, potentially yielding
cellulosic material and protein on a continuous year-round basis. A bench-top hybrid photobioreactor was developed to study
photomixotrophic and photoautotrophic growth of Glycine max as a model system. Maximum biomass doubling times for photomixotrophic
and photoautotrophic growth were 1.87 and 3.92 d, respectively. The presence of exogenous sugars resulted in photomixotrophic
growth, reduced chlorophyll levels, and a reduction in photosynthetically-evolved oxygen. Depletion of carbohydrates from
the medium coincided with the beginning of stationary phase and an increase in oxygen evolution by the cells. A second growth
phase, prolonging cell viability, could be initiated by increasing the carbon dioxide from 2 to 5%, just before the onset
of stationary phase. Biomass from bioreactor cultured cells proved resistant to enzymatic attack without pretreatment. Composition
of the biomass was 7.8% lignin, 20.7% α-cellulose, 23% hemicellulose, 5.5% starch, 14.5% protein and 6.5% nucleic acids. 相似文献
12.
神府烟煤以及贵阳贫煤分别与木屑掺烧灰沉积特性研究 《燃料化学学报》2003,48(9):1055-1062
利用CCD相机和沉积探针组成的在线监测系统,在50 kW下行炉上研究了木屑与神府烟煤以及贵阳贫煤的掺烧灰沉积特性。灰渣沉积过程可分为三个阶段:缓慢增长阶段、快速增长阶段和稳定阶段。烟煤掺烧灰沉积厚度随着木屑掺烧比例的增加而增加,贫煤掺烧灰沉积厚度则随着木屑掺烧比例增加而减小。烟煤中掺烧木屑比例为0、6.7%、15%和22%时,渣层稳定厚度分别为1.37、3.85、11.50、20.56 mm,稳定相对热流密度分别为0.44、0.41、0.30、0.26。贫煤掺烧木屑比例为6.7%、15%和22%时,稳定厚度分别为18.65、10.97和9.78 mm,稳定相对热流密度分别为0.29、0.31、0.33。掺烧木屑之后,灰渣初始层中Ca、K元素显著增加。在相同温度下,随着木屑掺烧比例的增加,灰中熔融相比例增加,因为木屑灰分中含有较多的Na2O、K2O等碱金属氧化物,而Al2O3、SiO2等含量较少,降低了灰的熔融温度。 相似文献
13.
Patricia MerdyEmmanuel Guillon Jacques DumonceauMichel Aplincourt 《Analytica chimica acta》2002,459(1):133-142
Comparative studies using various analytical and spectroscopic techniques have been carried out on three samples of lignin: two samples of natural lignin that have been extracted using different processes, and one sample of synthetic lignin. This paper discusses the general features common to all three kinds of lignin, as well as the differences between, on one hand, the two natural lignins coming from different extraction processes, and, on the other hand, the natural lignins and the synthetic one. The advantages of each technique in explaining the structure of these three different lignins are emphasised. 相似文献
14.
轻工业纤维素生物质过程残渣能源化技术 总被引:1,自引:0,他引:1
以农产品为原料的轻工业大都是典型的流程工业,在通过转化过程将原料转化为食品、饮料、添加剂、调味料、纸和中成药等产品的同时产生被称为过程残渣的固体废物与废料,如白酒糟、酒精糟、醋糟、甘蔗渣、中药渣、油粕、酱渣、菌渣和造纸黑液可熔渣等.这些残渣产生于特定的生产过程,富含纤维素、蛋白质或木质素,因此代表一种已经被集中的生物质资源.它们同时含水50%-80%、易腐烂变质、甚至呈弱酸碱性,因此是重要的环境污染源.本文着眼于轻工生物质过程残渣的高值化利用,分析指出富含纤维素的白酒糟、醋糟、甘蔗渣、中药渣、茶渣和造纸边角料等适合作为生物质能源而被转化利用,并根据资源特征提出了可能的技术路线.通过分别对热化学路线涉及的脱水干燥、燃烧发电与气化发电技术和集成乙醇发酵、沼气发酵的复合转化技术进行技术综述,最后针对不同规模的富含纤维素轻工生物质过程残渣能源化提供了技术选择建议. 相似文献
15.
16.
硬木热解过程中颗粒内部二次反应的数值研究Ⅱ.数值模拟结果 总被引:1,自引:4,他引:1
为了研究生物质(硬木)热解过程中颗粒内部的二次反应,对流化床环境下单颗粒生物质热解模型进行了求解。计算针对典型大颗粒和典型小颗粒在流化床反应器反应条件下的热解过程,对不同大小颗粒内部各种产物的生成、消耗、积累以及逃逸行为进行了定量描述。计算结果表明:对于直径为2mm的小颗粒,颗粒内二次裂解的份额可以忽略,但是对于直径10mm的大颗粒,热争过程中有超过20%的一次焦油参加了颗粒内部二次反应,颗粒内二次裂解显著地改变了热解产物分布,改变了热解产物的品质。 相似文献
17.
Development of a multicriteria assessment model for ranking biomass feedstock collection and transportation systems 总被引:1,自引:0,他引:1
Amit Kumar Shahab Sokhansanj Peter C. Flynn 《Applied biochemistry and biotechnology》2006,129(1-3):71-87
This study details multicriteria assessment methodology that integrates economic, social, environmental, and technical factors
in order to rank alternatives for biomass collection and transportation systems. Ranking of biomass collection systems is
based on cost of delivered biomass, quality of biomass supplied, emissions during collection, energy input to the chain operations,
and maturity of supply system technologies. The assessment methodology is used to evaluate alternatives for collecting 1.8×106 dry t/yr based on assumptions made on performance of various assemblies of biomass collection systems is based on cost of
delivered biomass, quality of biomass supplied, emissions during collection, energy input to the chain operations, and maturity
of supply system technologies. The assessment methodology is used to evaluate alternatives for collecting 1.8×106 dry t/yr based on assumptions made on performance of various assemblies of biomass collection systems. A proposed collection
option using loafer/stacker was shown to be the best option followed by ensiling and baling. Ranking of biomass transport
systems is based on cost of biomass transport, emissions during transport, traffic congestion, and maturity of different technologies.
At a capacity of 4×106 dry t/yr, rail transport was shown to be the best option, followed by truck transport and pipeline transport, respectively.
These rankings depend highly on assumed maturity of technologies and scale of utilization. These may change if technologies
such as loafing or ensiling (wet storage) methods are proved to be infeasible for large-scale collection systems. 相似文献
18.
生物质热解油气化试验研究 总被引:14,自引:1,他引:14
生物质是一种环境友好可再生资源,可以通过多种途径转化为液体燃料。生物质热解液化即是在缺氧状态下对生物质进行快速加热,然后再对热解产物进行快速冷凝,最后获得一种称为生物油的液体燃料的技术。该技术以及生物油的特点主要有:热解液化温度为500℃,远低于生物质热解气化所 相似文献
19.
The effect of ammonium nitrate concentration in the citric acid biosynthesis by Aspergillus niger NC-12 in single-stage continuous cultures with biomass retention was investigated. Experiments were carried out in a BIOMER
laboratory fermenter with 5 dm3 working volume. At the initial stage of each cultivation, the substrate in the bioreactor contained 1.5 g NH4NO3 dm−3. After 120 h onwards, the bioreactor was fed continuously at a constant dilution rate of 0.009 h−1. NH4NO3 concentration in the feed was varied from one culture to another, ranging between 0.5 g dm−3 and 2.5 g dm−3. Promising results were obtained when NH4NO3 concentration of 1.5 g dm−3 was used. The observed concentration of citric acid (c
P) and yield of citric acid with respect to the introduced sucrose (Y
P/S) were 117.88 g dm−3 and 78.59 %, respectively. The efficiency coefficient of citric acid biosynthesis (K
ef) was very high, amounting to 83.38.
Presented at the 33rd International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 22–26 May
2006. 相似文献
20.
《Journal of polymer science. Part A, Polymer chemistry》2018,56(14):1516-1519
Polyamide composed of furan dimer, which is prepared from biomass‐derived organic molecule 2‐furfural, is synthesized. The reaction of 2,2′‐furan dimer 5,5′‐dicarbonyl chloride with several 1,ω‐diamines was carried out with a solution or interfacial polycondensation leading to the corresponding polyamide. Measurement of the melting point was performed resulting to exhibit a higher temperature compared with the related polyamide bearing a single furan ring composed of furan‐2,5‐dicarboxylic acid (FDCA). Thermal analyses (TG–DTA) also indicated higher temperatures of decomposition than those of FDCA‐derived polyamide. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1516–1519 相似文献