应用XPS研究煤中有机硫在脱硫时的存在形态

应用Ｘ－射线光电能谱（ＸＰＳ）研究了几种煤中有机硫在脱硫过程中的存在形态。通过模型化合物（ｍｏｄｅｌｃｏｍｐｏｕｎｄｓ）中硫的２Ｐ层电子的ＸＰＳ结合能，可用来估算煤中硫的归属，如硫醇，硫醚及噻吩类硫，南桐东林煤中有机硫以噻吩型硫为主，亦存在少量硫醇以醚型硫，兖州北宿１６层煤则以噻粉硫硫氧化合物的为主，用乙醇超临界抽提及高能辐射处理２种煤样，均能脱除一定量的有机硫，初步认为乙醇超临界提法能脱除煤中硫     

煤的生物加工

借助计算机对国际上关于煤及有关的有机化合物的微生物转化方面的文献进行了调研和述评,以便确定可能应用于煤生物加工的候选微生物和生物技术。关于煤生物加工的大多数文献都是论及通过脱除黄铁矿来脱硫,并提出了一些生物加工流程。最近还发表了脱除煤中有机硫和金属的几篇报告。到目前为止,还没有评述脱除煤中其他元素(如氧和氮)的文献。然而,用微生物降解了类似煤中某些重要含氧和合氮官能团的模型基质。这些微生物可能有希望用于煤的生物加工。     

国外煤炭燃前脱硫综述

<正> 一、微生物脱硫能够应用于煤脱硫领域的微生物种类很多,目前广泛采用的是硫杆菌属的氧化亚铁硫杆菌和氧化硫硫杆菌。Brierly 于70年代末期从酸性热温泉和富硫土壤中分离出了嗜热铁氧化菌。80年代末,美国大西洋研究公司成功地从自然生物种群中分离出了 CB1和CB2,这两种微生物对脱除煤中的噻吩硫等有机硫有特效。国外微生物脱除煤中无机硫的研究十分     

煤及其模型化合物电解氧化脱硫的热力学分析

根据煤的分子结构理论及热力学原理，对铁矿和有机含硫模型化俣物在标准状态下电解氧化硫的理论分解电压进行了计算，分析了电化学法脱除煤中有机硫和黄铁矿的可能性及脱硫深度，讨论了提高脱硫效率和选择性的可能途径。     

脱硫微生物的菌种驯化培养

生物脱硫具有低成本、可脱有机硫等优点,不足之处是菌种生长不稳定,需要不断进行驯化培养以提高菌种的脱硫活性。实验采用不同的硫源对脱硫微生物进行了驯化,考察了不同培养基中的微生物的驯化和生长,再将微生物菌种分别接种到煤、黄铁矿和柴油培养基中进行培养。结果表明,在以煤为硫源的培养基中,微生物生长具有较大起伏,不利于菌种的驯化,8d后的脱硫率为10.2%;而在柴油和黄铁矿中培养的微生物则较单一,有利于菌种的驯化,8d后的脱硫率分别为23%和17.4%。     

好氧微生物抑制煤自燃机理研究现状及展望

综述了微生物对煤脱硫、降解方面的研究现状，利用好氧微生物处理煤可降低煤中硫含量(黄铁矿)、破坏煤中羟基、羰基、羧基等活性基团以及消耗O₂、产生CO₂气体等特性，提出用生物技术来延缓煤氧化进程、阻断煤氧化路径从而抑制煤自燃的设想。基于利用微生物对煤表面环境状态以及微观结构改变的特性，从煤氧化反应本身为切入点防控煤自燃。针对好氧微生物改性驯化对煤中硫含量、活性基团的影响，对现阶段常用的煤炭脱硫、降解类微生物(如嗜酸氧化亚铁硫杆菌、黄孢原毛平革菌等)进行分析，总结了可用于抑制煤自燃的微生物生长特性及其差异性，最终提出可用多种功能微生物分步协同作用来抑制煤自燃的思路，对煤自燃新型绿色阻化剂的开发进行了展望。     

高硫煤热解脱硫技术研究现状

归纳了煤中硫赋存形态,阐述了热解脱硫研究的意义;根据热解过程脱硫方式,将热解脱硫分为不同气氛下热解脱硫和添加物共热解脱硫。不同气氛下热解脱硫方面,分析了惰性、氧化性、还原性3种气氛下热解脱硫效果,结果表明,还原性气氛下脱硫效果最佳,且被脱除的硫多以H2S形态逸出;炼焦煤热解形成焦炭,还原性氢仅与表面含硫化合物反应,脱硫效果有限,因此难以工业化应用。添加物共热解脱硫方面,分析了有机和无机添加物共热解的脱硫效果,结果表明,某些有机和无机添加物与煤共热解时具有脱硫效果,但对于脱除哪类形态硫及各形态硫脱除机理研究甚少;最后提出了热解脱硫技术研究的可能性方向。     

两种微生物对山西晋城中高硫煤脱硫最佳工艺条件研究

燃烧含硫煤炭会释放硫氧化物,导致雾霾、酸雨等环境问题,因此,煤中硫的降低或脱除至关重要。选用能够降解多环芳烃的恶臭假单胞菌和能够降解长链烷烃的茫崖诺卡氏菌对含硫量为2.66%的山西晋城中高硫煤进行微生物脱硫,通过单因素实验和正交实验探究了煤样粒度、煤浆质量浓度、脱硫时间、细菌接种量、培养基pH和培养温度对微生物脱除煤中硫的影响。利用红外光谱仪、X射线衍射仪和扫描电镜对原煤和脱硫后煤样进行了分析表征。结果显示恶臭假单胞菌最佳脱硫条件是：煤样粒度0.075 mm～0.125 mm,煤浆质量浓度0.008 g/mL,培养时间10 d,细菌接种量0.2 mL/mL,培养基pH 6.0、培养温度30℃。茫崖诺卡氏菌的最佳脱硫条件除了培养基pH为7.0与恶臭假单胞菌培养基pH不一样外,其他条件均一致。恶臭假单胞菌和茫崖诺卡氏菌在最佳脱硫条件下的脱硫率分别为38.0%和39.8%,脱硫后煤样中的全硫质量分数分别为1.65%和1.60%,表明经微生物脱硫后煤样含硫量均符合发电用煤S4等级(1.50%t)≤2.00%)。与原煤相比,脱硫后煤样的黄铁矿峰强度有所降低,部...     

一种高有机硫煤的化学药剂脱硫研究

选择复合脱硫剂在酸性条件下研究脱硫条件（煤浆浓度、处理时间、复合脱硫剂的浓度及溶液酸度）对高有机硫煤总硫、无机硫和有机硫脱硫率的影响．研究表明,煤浆浓度越低、处理时间越长、复合脱硫剂的浓度越大、处理溶液的酸度越大,总硫、无机硫和有机硫的脱硫率越大,最后对处理液和脱硫精煤进行了组分分析,探讨了酸性条件下复合脱硫剂脱除煤中总硫的反应及脱硫机理．     

氢气氛下半焦有机硫的脱除动力学

研究了半焦颗粒在氢气氛下有机硫脱除的本征动力学行为.实验采用微分反应器,研究结果表明,半焦颗粒的脱硫与气氛、温度和半焦硫含量有关.通过比较粒子反应模型和随机孔模型,粒子反应模型仅适合于处理半焦颗粒氢气气氛脱硫的初始阶段,而随机孔模型符合整个脱硫过程.实验和理论分析揭示了脱硫过程中煤中有机硫形态的转化.     

微生物浸滤法脱除煤中的黄铁矿

本文首先叙述了煤中黄铁矿的分布赋存规律。在此基础上，指出了微生物浸滤法脱除黄铁矿硫的产生背景及工艺过程，重点分析了常用的微生物的特征及其作用机理。最后，评述了微生物浸滤法脱除煤中黄铁矿硫的现状及发展动向。     

A MECHANISTIC MODEL FOR MICROBIAL UPTAKE OF HYDROCARBONS IN FLOCCULATING AND NONFLOCCULATING SYSTEMS

Hydrocarhon uptake was studied in three microbial systems with different flocculation characteristics. An integrated mechanistic model, based on different substrate sources, has been developed for both flocculating and nonflocculating hydrocarbon fermentation systems. Simulated growth kinetics were compared with experimental results. The model illustrates the role of microbial characteristics in uptake kinetics and identifies the controlling parameters to better understand microbial uptake of hydrocarbons.     

ON THE SPECIFIC RESISTANCE OF CAKES OF MICROORGANISMS

The mean specific resistance of the cakes of various microorganisms was evaluated by measurement of either a change in the amount of permeate with time or of steady-state flux under constant pressure. The mean specific resistance was different with different shapes and sizes of microorganisms. The large differences arose from different packing structures of the cake. The effect of a filter aid on the filtration rate and cake structure was studied experimentally and theoretically. The effects of a filter aid were best explained by a series model, in which a cake layer composed of microbial cells and a layer of randomly distributed microbial cells and filter aid are packed on the membrane surface in series with respect to the directions of permeation.     

OPTIMAL CONTROL OF THE PENICILLIN G FED-BATCH FERMENTATION: AN ANALYSIS OF A MODIFIED UNSTRUCTURED MODEL

This paper presents the application of optimal control theory in determining the optimal glucose feed rate profile for the penicillin G fed-batch fermentation, using a modified unstructured mathematical model based on balancing methods. This updated model allows for a smooth transition between maintenance and endogenous metabolism, while all variables take on physically acceptable values under all conditions

It is illustrated that the resulting computational algorithm is independent of the exact nature of the metabolism (maintenance or endogenous). In this scheme, the unusual optimization of some free initial states is included. However, as shown by simulations, the nature of the metabolism might be a key factor in concluding whether or not altering the substrate feeding strategy has an important influence on the final amount of product

Mathematical and microbial insight leads to the construction of an alternative suboptimal heuristic     

SCALING IN SITU BIOREMEDIATION PROBLEMS BY APPLICATION OF MULTIPHASE, MULTICOMPONENT TRANSPORT THEORY

A methodology for scaling in situ bioremediation problems is presented. This methodology is based on multiphase, muiticomponent transport theory and employs inspectional analysis and numerical sensitivity studies. A general mathematical model that describes subsurface aerobic biotransformation of organic chemical species in a multiphase setting is first presented. This general model is applied to the specific case of microbial enhanced vapor-vacuum extraction (MEVVE) in a one-dimensional zone of immobile liquids. The resulting simplified MEVVE model considers rate-dependent interphase mass transfer, a flowing gaseous phase, a single hydrocarbon pseudo-component, and either oxygen or hydrocarbon limited microbial activity. By inspectional analysis a set of dimensionless groups are derived that represent the various model parameters. A scries of numerical sensitivity studies are presented that examine the impact of selected dimensionless groups on overall system biotransformation rates. This analysis demonstrates that overall biotranformation rates can be significantly limited not only by insufficient transport of oxygen in the gaseous phase, but also by interfacial mass transfer resistance between nonaqueous phase liquid globules and adjacent fluids. Finally, an examination of the selected dimensionless groups reveals the parameter requirements for properly scaled MEVVE tests. These results indicate the need for further investigation of the importantance of fluid distributions in the pore space and their impact on the design of laboratory and field tests.     

Drag reduction effectiveness,shear stability and biodegradation resistance of guargum-based graft copolymers

Guargum is a seed galactomannan and is known to be a shear stable drag reducing agent. However, the aqueous solutions of guargum are very susceptible to microbial degradation. In the present investigation, seven graft copolymers of guargum and polyacrylamide have been synthesized and their drag reduction effectiveness, shear stability, and biodegradation resistance have been determined. It has been shown that the drag reduction effectiveness and shear stability of the graft copolymer depend upon the length of the graft and number of grafts in the molecule. None of the graft copolymer solutions show any microbial degradation up to 10 days.     

SELF-FORCING OF A CHEMOSTAT WITH SELF-SUSTAINED OSCILLATIONS FOR PRODUCTIVITY ENHANCEMENT

The effects of self-forcing simple limit-cycle type self-sustained oscillations (SSO) on a single chemostat with the aim to enhance its productivity was investigated using four different microbial systems with increasing complexities. It was demonstrated via simulation that for a chemostat with monod-type growth and with substrate-and-product-inhibited growth and product formation, it is possible to increase its productivity several fold by self-forcing the chemostat with SSO without incurring extra costs normally associated with external periodic forcing. Despite significant difference in the models used to simulate the chemostats, all four systems show a similar pattern of behavior in their productivity-vs.-mean residence time plots.     

尿素质量控制的应用研究

研究质量控制理论在大庆石化总厂化肥厂的应用，论述了质量管理的有关理论及使用方法、捷径。并对应用中的缺陷提出一些改进性建议。在此基础上建立了一套完整的质量控制自动模式，以期完善质量控制体系，提高企业质量控制的自动化水平。     

发酵罐中剪切环境与菌体形态和代谢

结合青霉素发酵过程,考察了产黄青霉形态与剪切环境的关系;在搅拌槽内流场研究的基础上,分析了现有各种表征发酵罐内总体剪切环境的参数的合理性,提出了菌体对高强度剪切呈现出“印象衰减”效应这一新观点.据此而得的特征剪切强度,可用于发酵罐中轴向、径向叶轮组合搅拌的设计.     

Drag-reduction efficiency,shear stability,and biodegradation resistance of carboxymethyl cellulose-based and starch-based graft copolymers

Graft copolymers of carboxymethyl cellulose and starch with polyacrylamide have been synthesized by grafting acrylamide onto carboxymethyl cellulose and starch, respectively, using a ceric-ion-initiated solution polymerization technique. These graft copolymers have been tested for their drag-reduction effectiveness, shear stability, and biodegradability. It has been shown that grafting enhances the drag-reduction effectiveness and shear stability and also that these factors are very much dependent on the length and number of grafts in the molecule. None of the graft copolymer solutions shows any microbial degradation up to 10 days.