隐球酵母Zwy-2-3循环利用油脂发酵废弃细胞产油

为提高资源利用效率,降低微生物油脂发酵成本,解决微生物油脂发酵中废弃酵母细胞和发酵废液处理排放的问题,研究隐球酵母(Cryptococcus podzolicus)Zwy-2-3利用栎类淀粉发酵产油情况,并探讨发酵废液和废弃酵母细胞酶解液作为氮源的循环利用.结果显示,以葡萄糖60 g/L和总氮0.18 g/L的废弃酵母细胞酶解液发酵时,循环3次其油脂产量分别达到6.79 g/L、6.66 g/L、6.72 g/L,均高于对照组;而将发酵废液回收用作废弃酵母细胞酶解的缓冲液时,其生物量、油脂产量同对照组相当;将该方法应用于栎类淀粉水解液同步糖化发酵产油脂的实验,循环3次后其生物量、油脂产量分别为13.04 g/L、7.13 g/L,比对照组提高了9.85%、10.03%,且3次循环的油脂含量较为稳定.油脂组分分析结果显示,菌株Zwy-2-3利用栎类淀粉同步糖化和废弃细胞循环酶解液发酵生产的微生物油脂不饱和脂肪酸的含量达到93%以上,与植物油组成相似.综上,酶解废弃酵母细胞可有效应用于酵母产油发酵,可为非粮淀粉生产的微生物油脂应用于生物柴油生产奠定基础.     

催化氧化法处理对硝基酚钠生产废水的研究

研究了催化氧化法处理对硝基酚钠生产废水的工艺参数，COD去除率可达90％，探讨了从酚钠母注人中盐析酚的条件，回收量为15．86Kg酚钠／m^3废液，提出了综合治理酚钠废水的工艺流程。     

麦草碱性亚硫酸钠法制纸浆碱回收

本文通过对麦草碱性亚硫酸钠制纸浆的废液进行湿裂化处理,把废液中的硅化合物变为SiO_2固体分离除去,以排除硅化合物在碱回收过程中造成的传热性能差、液体不易流送等干扰.对处理后的液体(黄液)进行汽提.燃烧、吸收等试验,找出了最佳工艺条件.研究结果表明,汽提可除去绝大部分S~(2-),燃烧可防止有机化合物的循环积累.黄液中的NaHCO_3及Na_2CO_3在吸收SO_2过程中可顺利地转化为Na_2SO_3直接用于蒸煮,同时避免了环境污染.     

从测试化学耗氧量的废液中回收制备硫酸银

本文提出一种铜置换出废液中银的方法,避免了废水中的杂质与银共析出,简化了制取纯银工艺,制取的银含量达99.9％以上。自制的纯银还可制成达化学试剂(A.R)标准的硫酸银试剂,作COD_(Cr)测定的循环利用。     

化学沉淀结合Fenton法预处理脱硫废液的原理与效果分析

脱硫废液因含有高浓度氰化物、硫氰化物、硫化物等有毒组分而影响焦化废水处理的生物工艺.以焦化企业产生的实际脱硫废液为研究对象,选用化学沉淀-Fenton氧化的串联方法尝试预处理及分析方法的可行性,通过单因素实验,考察了硫酸亚铁投加剂量、反应前后溶液pH值、反应时间3种条件对脱硫废液中总氰及易释放氰去除效果的影响,在优化条件下对经硫酸亚铁沉淀后的脱硫废液残液进行Fenton氧化实验.结果表明,当硫酸亚铁投加量为理论值的1.2倍,H2O2投加量为COD当量的0.3倍时,可使脱硫废液的COD去除率达到76.65%,使初始浓度分别为327.7、704.6和2087.3 mg.L-1的氰化物、硫氰化物及硫化物基本得到去除,为后续生物处理创造了有利条件.化学沉淀结合Fenton法是脱硫废液预处理效率高且实用的方法.     

闭路循环应用于金属表面处理行业的环境影响分析──生命周期分析的实例

本研究应用生命周期分析（lifecycleanalysis）的方法,对瑞典某金属表面处理工厂采用闭路循环工艺后的环境影响进行了分析。分析证明：闭路循环确可降低重金属对空气和水的污染,但增加了对不可再生能源的消耗,因而在采用该工艺时应特别关注能源问题．以期得到最好的环境效益。     

钢铁酸洗废液的资源化处理技术

钢铁酸洗废液中含有大量的酸和铁盐，已被各国作为危险废物进行管理，多年来，研究者已经研究出多种有效、可行的资源化处理方法和技术，从技术成熟性、工艺特性、工艺关键、过程控制、应用前景和发展方向等方面介绍了技术上比较成熟和具有良好前景的7种主要方法，以利于保护环境和酸洗废液资源化处理技术的进步。     

美国难处理金矿石预处理工艺的环境控制技术对比分析

在世界采金业综合评估的初步研究基础上。美国矿山局的一项研究评估了难处理金矿石加工预处理阶段的环境控制技术费用．考察了三种类型的难处理金矿石预处理的方法──焙烧、加压氧化和生物氧化．发现空气排放量焙烧法和加压氧化法情况下需要控制技术的主要污染类型，而废液排放在生物氧比法中受到更大关注．还发现，难处理金矿石预处理方怯的环境控制技术费用部分与总费用之比，除需要硫酸装置的焙烧炉情况外，其基本费用比高于运行费用比．　焙烧当存在若干种有毒元素时可能需要最复杂的环境控制技术设备，因而需要较高的捕获污染物费用．加压氧化需要少量污染物控制技术．焙烧、加压氧化和生物氧化都需要含砷废液处理．本研究发现，包括环境控制技术费用在内的多种因素决定预处理方法的选择．该选择过程中要考虑的因素是废物排放、矿石矿物学、金回收率和基本费用．当评估为本研究中所包括的若干种难处理金矿石作业选择的方案时，发现预处理工艺选择决定于冶金学考虑而不决定于环境控制技术费用．     

锌镀层退镀废液中锌酸治理回收技术

本研究以锌镀层退底废液中锌配备顺收为例探讨从盐酸体系中分离酸－金属的工艺特点，选取了高效又价廉的国产萃取剂（Ｎ－２３５）和反萃剂（生石灰），建立了新的回收处理工艺路线，中试结果证明此工艺在技术上和设备上是可行的。     

酸阻滞技术的研究与应用

本文提出酸阻滞法从废液中分离，回收重金属和酸的新技术工艺，从十多种国产树脂中成功地筛选出两种可作为酸阻滞剂，有较好的分离效果。但洗脱时酸脱尾严重，当选择穿透比在０．６左右时，可以解决酸脱尾现象，使脱尾酸损失由３０％降到７％，而酸的回收率由６０％提高到９０％，采用该工艺对几种废液进行处理，重金属回收液中酸去除率大于９５％，而回用酸中金属去除率大于７０％，该工艺既可回收重金属，同时也可回收酸。     

Optimization of fermentation process for saccharide-based fuel ethanol production by Saccharomyces cerevisiae北大核心CSCD

低成本、高产量的发酵工艺是实现工业燃料乙醇经济和环境可持续性发展的关键,而不需要重大基础设施改变或投资.为获得酿酒酵母(Saccharomyces cerevisiae)利用甘蔗汁生产燃料乙醇的最优发酵工艺,首先对发酵体系的氮源条件进行优化;其次,在单因素试验基础上,以乙醇发酵效率为响应值,通过响应面法优化了燃料乙醇生产的发酵工艺,并通过补料分批发酵技术在5 L发酵罐中进一步扩大发酵.结果表明,以1.0 g/L (NH)SO和1.0 g/L酵母提取物作为发酵氮源,乙醇发酵效率和得率比对照可分别提高4.80%、9.52%.响应面设计获得的最优发酵工艺条件为在总糖浓度150.0 g/L、酵母提取物浓度2.0 g/L、发酵时间24.5 h、pH5.0、外加(NH)SO浓度1.0 g/L时,最高乙醇发酵效率可达到91.10%.在5 L发酵罐中采用补料分批发酵获得的最终乙醇浓度达到98.92 g/L,发酵效率维持在90%左右,乙醇生产力最高达到3.81 g Lh.本研究获得了一种高效生产糖质燃料乙醇的发酵工艺,可在较短时间内获得高浓度乙醇且消耗较少氮源,结果可为进一步利用糖质原料进行高效生物炼制及高浓度乙醇工业化生产提供参考.(图6表6参30)     

高密度沉淀-活性砂过滤工艺在钢铁工业废水处理中的应用

采用调节池-高密度沉淀池-活性砂滤池-消毒为主要处理工艺,处理钢铁工业废水并回用,介绍该工艺技术特点、主要构筑物的技术参数以及运行效果。工程监测结果表明,该工艺对总硬度、浊度及COD的去除率分别达到60%、85%及62%以上,出水水质各项指标均达到《城市污水再生利用工业用水水质标准》(GB/T19923-2005)要求。处理系统运行稳定,耐冲击能力强。     

鲜甘薯发酵生产燃料乙醇中的降粘工艺

鲜甘薯高浓度发酵生产燃料乙醇的瓶颈之一是醪液粘度高,容易堵塞管路,严重影响工业化生产和增加能源消耗,同时也会降低乙醇发酵效率.为解决此问题,进行了添加降粘酶系及其作用条件优化研究,结果如下:1)确定最适降粘酶系为四川禾本生物工程有限公司的纤维素酶,粘度由1.7×104mPa.s降到8.8×102mPa.s,并且降低了生产成本;2)确定降粘酶作用前高温处理条件:110℃,20 min;3)最适降粘酶对不同品种鲜甘薯高浓度发酵的降粘效果表明降粘酶对大部分品种鲜甘薯降粘效果较好,粘度均约为1.0×103mPa.s以下,最低粘度只有2.7×102mPa.s,粘度下降率均在95%以上;4)在确定最适降粘酶系和其作用前高温条件后,将其应用于工业化生产,加入降粘酶2 h后发酵醪液的粘度由1.8×105mPa.s下降到2.7×103mPa.s,发酵后终粘度仅为7.9×102mPa.s,发酵时间仅为23 h,乙醇浓度达到10.56%(V/V),进一步验证了该降粘酶系应用于工业化鲜甘薯燃料乙醇生产的实际意义.表8参19     

Preliminary study of groundwater denitrification using a composite membrane bioreactor

A composite membrane bioreactor (CMBR) integrating the immobilized cell technique and the membrane separation technology was developed for groundwater denitrification. The CMBR had two well mixed compartments with one filled with the nitrate- containing influent and the other with a dilute ethanol solution; the compartments were separated by the composite membrane consisting of a microporous membrane facing the influent and an immobilized cell membrane facing the ethanol solution. Nitrate and ethanol molecules diffused from the respective compartments into the immobilized cell membrane where nitrate was reduced to gaseous nitrogen by the denitrifying bacteria present there with ethanol as the carbon source. The microporous membrane was attached to one side of the immobilized cell membrane for retention of the disaggregated bacteria. Relative to the single dose of external ethanol, the two-dose supplementation produced better treatment results as evidenced by the lower concentrations of NO3--N and ethanol (as measured by total organic carbon) of the effluent. The batch treatment in CMBR removed most of the nitrate in the influent and attained a stable denitrification rate of 0.1 g·m^-2·h^-1 for most of the 96-h cycles during the 30-cycle study. The effluent was essentially free of ethanol and nitrite nitrogen.     

Biomanagement of paper mill sludge using an indegenous (Lampito mauritii) and two exotic (Eudrilus eugineae and Eisenia foetida) earthworms

Paper mills have severe problem in disposing effluent or semisolid sludge despite repeated recycling. It requires treatment prior to disposal of sludge. In recent years biological treatment methods received much attention and considered as efficient low-cost treatment. One such method is vermiculture treatment. The present study was carried out to dispose the paper mill sludge biologically using 2 exotic species (Eudrilus eugineae and Eiseniafoetida) and an indigenous species (Lampito mauritii) of earthworm. The paper mill sludge in various concentration 25%,50% and 75% were subjected to vermitub treatment for a period of 60 days. During the period of study data were collected on reproductive strategies of earthworm and chemical analysis of wastes before and after treatment. Results obtained indicate that 25% concentration of sludge was ideal and of the three worms used Eiseniafoetida proved to be the best worm for biomanagement.     

Effect of wetland plant fermentation broth on nitrogen removal and bioenergy generation in constructed wetland-microbial fuel cells

● Fermentation broth facilitates N removal and energy yields in tertiary CW-MFC. ● Carbon sources are preferred for nitrogen removal over electricity generation. ● A mutual promotion relationship exists between acetic and humic acid in N removal. ● Humic acid boosts the abundances of functional genes relate to nitrogen metabolism. Constructed wetlands (CWs) are widely used as a tertiary treatment technology, and the addition of carbon sources can significantly improve advanced nitrogen removal. However, excessive carbon sources would lead to an increase in the effluent chemical oxygen demand in CWs, and microbial fuel cells (MFCs) can convert these into electricity. In this study, constructed wetland-microbial fuel cells (CW-MFCs) were built to achieve simultaneous nitrogen removal and electricity generation, using wetland plant litter fermentation broths as carbon sources. The total nitrogen removal in the groups with fermentation broth addition (FGs) reached 83.33%, which was 19.64% higher than that in the CG (group without fermentation broth), and the mean voltages in the FGs were at least 2.6 times higher than that of the CG. Furthermore, two main components of the fermentation broths, acetic acid (Ac) and humic acid (HA), were identified using a three-dimensional excitation emission matrix and gas chromatograph and added to CW-MFCs to explore the influence mechanism on the treatment performance. Denitrification and electrogenesis presented the same tendency: Ac&HA > Ac > CG’ (groups without Ac and HA). These results indicate that Ac and HA increased the abundance of functional genes associated with nitrogen metabolism and electron transfer. This study demonstrated that CW-MFC fermentation broth addition can be a potential strategy for the disposal of secondary effluent and bioelectricity generation.     

Combinatorial effects of distillery and sugar factory effluents in crop plants

Under the reutilization and recycling strategy of industrial effluents, treated distillery and sugar factory mixed effluent was used in petridish culture experiments to investigate its effect on seed germination and seedling growth in wheat, garden pea, black gram and mustard. The seed germination and seedling growth were significantly reduced with increase in concentration of the effluent. The fresh matter was found significantly increased in barley (1.16 g per seedling in 25% dilution level of effluents in comparison to 0.93 in control), while other higher dilution levels reduce it. Wheat, garden pea, black gram, mustard invariably showed inhibition in fresh weight. Dry weight was found consistently reduced or unchanged in different treatments. Total chlorophyll contents in barley were significantly increased in different treatments (2.351 and 2.721 mg/g fresh weight of tissue at 25, 50% dilution levels in comparison to 1.781 of control) while in other crop it was reduced alloverthe treatments. Amylase activity in wheat, garden pea, black gram and mustard was reduced in all the treatments. Only in barley its level was enhanced from 0.76 to 0.85, 0.96, 0.81 in 25, 50, 75% dilution levels of the effluent mixture respectively Based on the data of different crops barley was found to be highly tolerant as the 25 and 50% dilution levels of combined effluents. It showed no change in germination %, while seedling growth was increased in lower dilution levels of combined effluent as compared to control Barley>garden pea>wheat>black gram>mustard gradually showed increased level of sensitivity respectively Most detrimental effects were seen in mustard. This toxicity might be due to excess of nutrients, beyond the limits of tolerance. Therefore, the higher concentration of mixed effluent was not advisable for irrigation purpose, however it could be used for irrigation purpose after proper treatment and dilution (one part treated effluent and five parts of available irrigation water), as this dilution level was found growth and yield promotory     

Biomanagement of petrochemical sludge using an exotic earthworm Eudrilus eugineae

Petrochemical industry have severe problem in disposing effluent and semisolid sludge despite repeated recycling. It requires further treatment prior to disposal of sludge. In recent years biological treatment methods received much attention and considered as an efficient low-cost treatment. One such method is vermiculture treatment The end product of vermicompost is rich in essential micro and macronutrients along with microorganisms in a very simple form. Adding cast, not only improves the soil structure and fertility but also leads to improvement in overall plant growth and thus increase their yield. The present study was carried out to dispose the petrochemical sludge biologically using an exotic earthworm Eudrilus eugineae. The petrochemical sludge at various concentrations 25, 50 and 75% were subjected to vermicomposting treatment for a period of 60 days. During the period of study, data were collected on life form of earthworm and chemical analysis of the sludge before and after treatment. The microbial analysis was carried out fortnightly. The results indicate that 25 and 50% concentration of sludge was ideal for the vermicomposting, whereas the higher concentration inhibits the vermicomposting.     

木质纤维素生产燃料乙醇的关键技术研究现状

木质纤维素是自然界广泛存在且廉价的可再生资源.其主要成分纤维索、半纤维素是潜在的燃料乙醇生产原料.虽然由木质纤维素生产燃料乙醇的技术路线已具可行性,但存在着具体工艺环节复杂、生产能耗高等局限,严重阻碍了其规模化生产.目前纤维素燃料乙醇生产主要围绕预处理、酶解、发酵三大关键步骤进行技术攻关,其中预处理的能耗和效率、发酵过程的五碳糖利用等问题成为该工艺的重要制约因素.本文在综述国内外纤维素乙醇生产关键步骤的基础上,着重分析了各种物理、化学和生物预处理的优缺点以及新兴的预处理思路,归纳了各类纤维素乙醇生产菌的特点,包括耐高温和五碳糖的利用,并介绍了当前主要的发酵方式和优化措施,以期为木质纤维素生产乙醇提供新的研究思路.表5参86     

一次性餐盒材料中全氟辛酸和全氟辛烷磺酸沥出性研究

利用高效液相色谱-串联质谱检测方法对一次性餐盒材料中可沥出性全氟辛酸(PFOA)和全氟辛烷磺酸(PFPS)进行了研究.分别选取水、3%乙酸(W/W)、15%乙醇(V/V)和正己烷4种浸取液模拟餐盒材料在使用过程中可能接触到的水性、酸性、酒精类和油脂类条件.材料经4种溶液浸提后,浸取液用固相萃取净化和浓缩,目标分析物PFOA和PFOS采用内标法进行定量.研究表明,一次性餐盒材料在模拟条件下中有以PFOA为主的伞氟类化合物从材料中沥出,其中酸性环境对PFOA的浸取率最高(2296 ng·m~(-2)), 为其它3种方法的82.8倍;4种浸提条件下PFPS的沥出率都比较低,浓度仪为0.7 ng·m~(-2)-5.4 ng·m~(-2).