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The PIROGAS process consists in replacing, in part or in total, the hot blast blown through the blast furnace tuyeres by reducing gas heated to a temperature of about 2000°C. The heating or the overheating and, eventually, the production of the reducing gas, can be achieved directly in the plasma heater. Up to 80% of the coke required for a conventional blast furnace operation can be replaced by substitute fuels. The PIROGAS process makes it possible to optimize the ratio between fossil fuels and electric power consumption to achieve an economic optimum. Trials carried out on an experimental blast furnace have shown that an operation with co'~e consumption as low as 105 kg of coke/ton of hot metal can be easily attained. Furthermore, it appeared during these trials that the quality of the hot metal can be instantaneously modified by appropriate action on reducing gas temperature and composition. Thus, the control of the process becomes easier and more rapid. Trials carried out on a full size commercial blast furnace have confirmed that the plasma heater in no way disturbs the operation of the blast furnace and, reciprocally, the unavoidable fluctuations in blast furnace operation do not perturb the functioning of the plasma heater. Plasma heaters have a high thermal efficiency (80%) and their electrical behaviour is excellent (power factor 0.92; no harmonics). 相似文献
976.
木质纤维素资源丰富,高效制取可利用的纤维素水解糖是实现其高附加值产品生产的关键,能够促进后续生物基产品的开发和产业化进程。预处理和水解糖化技术将木质纤维素转化为含有单糖的纤维素水解液,利用活性碳和离子交换等方法净化脱毒后的水解液再经浓缩、结晶等步骤最终可获得纤维素水解糖晶体。文章综述了木质纤维素水解糖制取中原料的预处理、水解糖化、净化脱毒和浓缩结晶等关键技术的最新研究进展,并展望了今后的发展趋势。 相似文献
977.
研究了乳酸精制过程中硫酸浓度、酸解温度对脱除总糖的作用,得出了酸解最佳工艺条件为:硫酸浓度98%,酸解温度为95℃,此时,残糖脱除率为96.2%。 相似文献
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979.
基于近红外光谱的梨果糖浓度无损检测系统 总被引:1,自引:0,他引:1
应用近红外光谱漫发射技术设计了梨果的糖浓度无损便携式检测系统,建立了近红外光谱和梨的糖浓度值之间的关系。以850nm激光二极管作为背景光源,905nm作为特征光源,设计了用于梨的糖浓度无损检测的便携式仪器。将校正集样本结合偏最小二乘法进行建模,并对预测集进行预测。同时使用标准仪器测得梨果糖度标准值,得到了标准糖度值和预测值之间的相关图。其中校正集相关系数为0.99186,RMSEC为0.00175,由此模型进行预测时所得到的预测集相关系数为0.8262,RMSEP=0.00808。实验初步证明,文中所设计仪器可对同一种类的梨的糖浓度进行无损测量。 相似文献
980.
Zareian M Ebrahimpour A Bakar FA Mohamed AK Forghani B Ab-Kadir MS Saari N 《International journal of molecular sciences》2012,13(5):5482-5497
l-glutamaic acid is the principal excitatory neurotransmitter in the brain and an important intermediate in metabolism. In the present study, lactic acid bacteria (218) were isolated from six different fermented foods as potent sources of glutamic acid producers. The presumptive bacteria were tested for their ability to synthesize glutamic acid. Out of the 35 strains showing this capability, strain MNZ was determined as the highest glutamic-acid producer. Identification tests including 16S rRNA gene sequencing and sugar assimilation ability identified the strain MNZ as Lactobacillus plantarum. The characteristics of this microorganism related to its glutamic acid-producing ability, growth rate, glucose consumption and pH profile were studied. Results revealed that glutamic acid was formed inside the cell and excreted into the extracellular medium. Glutamic acid production was found to be growth-associated and glucose significantly enhanced glutamic acid production (1.032 mmol/L) compared to other carbon sources. A concentration of 0.7% ammonium nitrate as a nitrogen source effectively enhanced glutamic acid production. To the best of our knowledge this is the first report of glutamic acid production by lactic acid bacteria. The results of this study can be further applied for developing functional foods enriched in glutamic acid and subsequently γ-amino butyric acid (GABA) as a bioactive compound. 相似文献