967 resultados para Waste paper


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造纸行业是造成我国水环境有机污染物的重要污染源之一,其水污染的特点是小厂多、草浆多、工艺落后、污染扩散面广、造成废 水排放量大,每年排放的废水量约39亿立方米,占全国工业废水排放量的1/6,其中有机污染物(以BOD5计)160万吨左右,约占全 国工业废水中有机污染物总量的1/4。尤以占全国制浆造纸行业90%以上的碱法草浆造纸厂的蒸煮黑液量大面广,除含有机物外,还 含有木质素、残碱、硫化物、氯化物等污染物,属于PH值高、色度深、难于治理的高浓度有机废水,对水体污染特别严重,各地要 求治理呼声很高,急待研究并尽快找出各种有效的治理途径。对于碱法草浆蒸煮,黑液高浓度废水的治理,有各种方法,根据国内 的研究进展和我们已有试验工作表明,最经济有效,具有实用价值,在生产上可获得成功是厌氧处理法。近10多年来,国外关于高 效厌氧处理技术研究进展迅速,并出现了多种多样的工艺设备,如高效厌氧生物反应器,并在实用化方面取得了很大成绩,建立了 生产性装置,达到了高负荷运行,效果良好。本试验是根据我们已有研究基础,针对我国国情,对小型制浆造纸厂水污染防治除了 开发碱回收及各种综合利用技术外,要特别加强废水(废液)实用技术研究的指导思想,本试验采用改进型的上流式厌氧污泥床反应 器,设计了两种试验方案,通过试验结果如下。1. 试验方案I—碱法草浆黑液酸化和厌氧发酵I号UASB反应器动态模型试验结果表 明:(1). 采用中温35℃±1℃高效厌氧反应器USAB内装有填料(陶粒)和三相分离器,具有保持高浓度生物量和防止污泥流失的特点 ,污泥浓度Vs 可达30%以上,因而具有高效、节能、产能、滞留期短的优点,当进水CODcr在7500-10000mg/l,HRT由7天缩短到3天 ,有机容积负荷在1.22gCODcr/l·d-3.43gCODcr/l·d时,CODcr平均去除率可达55%-45.5%,最高CODcr去除率可达60.2-63.5%, BOD5去除率可达75.9-83.2%,沼气容积产气率可达0.29-0.67l/l·d,每克CODcr转化为沼气产率达0.39-0.48l/gCODcr·d,CH4含量 65.8-75.5%。厌氧发酵出水再用化学法进行后处理脱除难降解的木质素,CODcr总去除率达80%以上。(2). 动态试验结果表明:采 用酸化—厌氧发酵处理黑液工艺合理,技术路线可行。2. 试验方案II—黑液用化学法(Hcl)去除木质素进行厌氧发酵,II号UASB反 应器动态模型试验结果表明:(1). 采用中温35℃±1℃高效厌氧反应器UASB(内有软填料),当进水CODcr7000-13000mg/l左右,HRT 由6天缩短到1天,有机负荷由0.98gCODcr/l·d增加到11gCODcr/l·d时,COD平均去除率均可稳定在70-77%,BOD5去除率为87.3- 93.1%,沼气容积产气率0.21-2.6l/l·d,每克CODcr转化为沼气产率为0.39-0.48l/gCODcr·d,高的可达0.53l/gCODcr·d,转化 率较高,CH4含量63-70%。(2). 试验证明碱法草浆黑液物化预处理—厌氧发酵处理的技术路线也是可行的,工艺合理、效果较好。 在有条件的工厂可采用。3.厌氧发酵阶段几大类群微生物计数表明:(1). 当发酵工艺和运行处于相对稳定状态时,微生物群体的 组成也达到相对的稳定,各类微生物之间保持动态平衡关系。当产乙酸菌的数量为107-108个/ml时,产甲烷菌的数量为105-106 个/ml,当产乙酸菌数量为106-107个/ml时,产甲烷菌的数量为103-105个/ml。(2).稳态运行条件下,黑液预处理为甲烷发酵创造 了有利的生态环境,获得了较好的处理效果和较高的COD转化为沼气的产率0.39-0.48l/g·CODcr·d,反应器中形成较为稳定而数 量较下水污泥中高1-2个数量级的厌氧发酵微生物区系组成。这一结果为黑液厌氧发酵提供了微生物理论依据。Paper industry is one of the important pollution source of water environment in our country. Its character of water pollution is many small factories, much grass pulp, disadvantageous technique, large preading area of pullution. Its effluent makes up 1/6 of whole country's industry wastwater. Its organic pollutant accounts 1/4 of whole country's. Alkaline grass paper pulp effluent with pollutants such as ligoin, remaining alkali sulfide, chloride besides organic material, is a kind of high concentrate organic wastewater which has high PH walug, dark colour and is difficult in treatment. There is urgent require to find ways to treat the wastewater. There are different ways to treat alkaline paper grass pulp effluent. According to the research advances and our experiment work, the most economical and useful way is anaerobic degradation which was advanced quick in last ten years. In the control of waste water of small pulp paper mill, the study of wastewater utilization technology should be emphasized, besides alkaline retrieving and different kinds of comprehensive utilization technology. Our experiment used modified UASB(Upflow Anaerobic Sludge Blanket Reactor). Two kinds of plan were disgned. The results are lined below. 1. The first experiment plant-aciding black pulp effluent and methanogenic digestion. The dynamic model experiment results of I-UASB reactor showed: (1)The mesophilic(35℃±1℃)high effect UASB reactor having haydite and threee state seperation in it had the character of keeping high bioimass concentration and preventing losss of sludge. It had advantages of high effect, energe saving, energe prodcing and short HRT(Hydroulic retention time). When the influent COD was 7500-10000mg, HRT was shortened from 7 days to 3days, organic loading rate was 1.22g-3.43COD/l· d, the average COD removal efficiency was 55%-45%. The highest COD efficiency was 60.2-63.5%, BOD removal of 75.9 -83.4% was achieved. Biogass production rate were up to 0.29-0.67l/l·d. Biogass converted efficiency from every gram of COD could reach 0.39-0.48l/gCOD·d. Methane content was 65.0-75.5%. Chemical method was used to deplate lignin in anaerobic digestion effluent. Total COD removal efficiency could be more than 80%. (2)Using aciding annaerobic digestion to treat the black effluent was reseanable in technique and technology. 2. The second experiment plan-anaerobic digestion was used after the chemical method was used to deplate lignin in the black effluent. The result of dynamic experiment of II-UASB reactor showed: (1)High effect mesophilic (35℃±1℃)UASB reactor having soft slaffing in was used. When influent COD was about 7000-13000mg/l, HRT was shortened from 6 days to 1 day and organic loading rate was increased from 0.90 to 11g COD /l·d, average COD removal efficiency remained stable on 70-77%. BOD, removal efficiency was between 87.3-93.1%. Biogass production rate was 0.2-2.6l/l ·d .Biogass converted efficiency from a gram of COD was 0.39-0.481/gCOD·d with the high value of 0.53l/gCOD·d. Methane content was 63-70%. (2)The way that using physical, chemical Pre-treatment-anaerobic digestion to treat alkaline black effluent is feasible and can be used in some factories when the condition exists. 3. Counting of several class of microoganisms in anaerobic digestion stage showed: (1)As the disgestion was in stable motion, the compositon of microorganic colony could get relative stable. Dynamic balance was remaining among different kinds of microorganism such as methanogenic bacteria, Acidogenic bacteria, sulfate reducing bacteria, and heterotrophic bacteria. (2)Under stable motion, the pre-treatment of black effluent produced favourable eco-enviroment for methanegenic digestion. Good treatment effect and high biogass convertent efficiency from COD(0.39-0.48l/g·COD· d)were gotten. Some stable and high quantity(10-100times more than sewage sludge)microorganism colony were formed in the reactor. This result provided theoretical basis for anaerobic digestion of black effluent.

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垃圾卫生填埋是国内外城市垃圾的主要处置方法。垃圾渗滤液是渗入填埋场垃圾的降水混合垃圾降解过程中产生的物质而形成的混合物,是垃圾填埋场向环境排放的主要污染物。渗滤液由于其所含高浓度有机和无机污染物,且其中很多物质有生物毒性或难生物降解,难于治理。特别是到填埋晚期,渗滤液中高浓度的氨氮更是增加了治理的难度。渗滤液场外硝化-原位反硝化是填埋场氮管理的新途径。本文利用从环境中筛选出优势硝化功能菌对渗滤液中的高浓度氨氮进行生物硝化,经硝化后的渗滤液回灌至以垃圾柱模拟的生物反应器填埋场,在填埋场内实现原位反硝化。 上述目标通过以下两部分来实现: 第一部分:渗滤液场外硝化。首先从污水厂的硝化污泥中富集并筛选出硝化功能菌,在模拟氨氮废水中优化。将驯化的硝化功能菌接种于连续式完全混合反应器(CSTR)进行高氨氮渗滤液硝化研究。在200余天的连续运行中,反应器硝化和有机物去除效果良好。在最大氨氮负荷和有机物负荷分别为0.65 g N l-1 d-1 和3.84 g COD l-1 d-1时,氨氮和COD去除率分别高于99%和57%。实验过程中发现,游离氨(FA)和溶解氧(DO)浓度对反应器中亚硝酸盐的积累影响很大。 第二部分:渗滤液原位反硝化。本文利用一个垃圾填充柱模拟生物反应器填埋场,研究了硝化渗滤液回灌对垃圾降解的影响,和回灌的硝化渗滤液中TON(总氧化态氮)对填埋场生物反应器产甲烷作用的影响。最后利用变性梯度凝胶电泳(DGGE)分析了硝化渗滤液回灌对垃圾填埋场菌群结构的影响。结果表明:回灌的TON被完全还原,反硝化为主要反应,最大TON负荷为28.6 mg N kg-1 TS d-1。当垃圾柱TON负荷大于11.4 mg N kg-1 TS d-1时,出现了产甲烷抑制,抑制作用随TON负荷的增加而加强。在此过程中,反硝化逐渐代替产甲烷作用成为填埋场内垃圾降解的主要反应,且更多产生的是清洁的氮气,而非温室气体甲烷。直到实验结束时,回灌硝化渗滤液的垃圾柱的甲烷产量仅相当于对照的2.5%,并且回灌的硝化渗滤液还加速了填埋场垃圾的降解与稳定。通过DGGE进行菌群结构分析发现,由于TON对填埋场的长期作用,反硝化菌增多而产甲烷菌减少。 Landfill still remains the chief method for MSW management around the world. Leachate is a mixture of rainfall permeating through landfill and organic and inorganic matters generated during decomposition of the wastes in the landfills, characterized as highly complicated and refractory wastewater. Ex-situ nitrification and sequential in-situ denitrification represents a novel approach to nitrogen management at landfills. In the present paper, nitrification was carried out in a continuous stirred tank reactor (CSTR) inoculated with nitrifying bacteria which were isolated from municipal WWTP of Chengdu city. The nitrified leachate from CSTR was recirculated to a lab-scale municipal solid waste (MSW) column where in-situ denitrification took place. The above object was achived through two parts as following: First, ex-situ nitification of leachate. After acclimated in simulated wastewater for 3 month, nitrifying bacteria isolated from WWTP nitrifying sludge were added to the CSTR for nitrification. The results over 200 days showed that the maximum nitrogen loading rate (NLR) and the maximum organic loading rate (OLR) was 0.65 g N l-1 d-1 and 3.84 g COD l-1 d-1, respectively. The ammonia and COD removal was over 99% and 57%, respectively. Moreover, the effects of free ammonia (FA) and dissolved oxygen (DO) on nitrification were investigated. Second, in-situ denitrification was studied in a municipal solid waste (MSW) column. Variation of nitrified leachate and its effects on the decomposition of municipal solid waste (MSW) were studied in a lab-scale MSW column to which nitrified leachate was recirculated. Additionally, DGGE was employed to investigate the microbial community of both MSW columns. The results suggested: complete reduction of total oxidized nitrogen (TON) was obtained with maximum TON load of 28.6 mg N kg-1 TS d-1 and denitrification was the main reaction responsible. Methanogenesis inhibition was observed while TON load was over 11.4 mg N kg-1 TS d-1 and the inhibition was enhanced with the increase of TON load. Denitrification gradually took over methanogenesis to become the main reaction responsible for decomposition of MSW while nitrogen gas, a clean byproduct, was generated instead. Till the end of the experiment, the average weekly methane production in the denitrification column was as low as 2.5% of that of the control, and the rate of decompition and stability of MSW was accelerated by the recirculation of the nitrified leachate.Owing to long term exposure of nitrified leachate to landfill, denitrifying bacteria increased and methanogen decreased.

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During the past. decades, large-scale national neutron sources have been developed in Asia, Europe, and North America. Complementing such efforts, compact hadron beam complexes and neutron sources intended to serve primarily universities and industrial institutes have been proposed, and some have recently been established. Responding to the demand in China for pulsed neutron/proton-beam platforms that are dedicated to fundamental and applied research for users in multiple disciplines from materials characterization to hadron therapy and radiography to accelerator-driven sub-critical reactor systems (ADS) for nuclear waste transmutation, we have initiated the construction of a compact, yet expandable, accelerator complex-the Compact Pulsed Hadron Source (CPHS). It consists of an accelerator front-end (a high-intensity ion source, a 3-MeV radio-frequency quadrupole linac (RFQ), and a 13-MeV drift-tube linac (DTL)), a neutron target station (a beryllium target with solid methane and room-temperature water moderators/reflector), and experimental stations for neutron imaging/radiography, small-angle scattering, and proton irradiation. In the future, the CPHS may also serve as an injector to a ring for proton therapy and radiography or as the front end to an ADS test facility. In this paper, we describe the design of the CPHS technical systems and its intended operation.

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铝类絮凝剂对细颗粒泥沙絮凝沉降有重要作用 ,常应用于浑水澄清、农业污水处理等研究中。在AlCl3 浓度为 0~ 1 7mmol/L ,泥沙浓度为 1 0g/L时 ,用吸管法研究了AlCl3 对细颗粒泥沙絮凝沉降的影响 ,结果表明 :在液面下同一深度 ,泥沙浓度随时间呈指数衰减 ;悬液经多次搅拌后再沉降 ,其沉速减缓 ;当AlCl3 浓度为 0 9~ 1 7mmol/L时 ,出现明显的清浑水交界面 ,交界面随时间等速下降 ,平均沉速为 4 75 6cm/min ,对应的絮团平均粒径为 0 0 31 5mm ;土娄土絮凝临界粒径为 0 0 2 7mm。

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The solution of non-volatile solutes can be concentrated to saturation by membrane distillation. If the solute is easy to crystalize, the membrane distillation-crystallization phenomenon will appear during the membrane distillation of saturated solutions. It is possible that crystalline products are separated from concentrated solutions by a membrane process. In this work the PVDF capillary membrane, which was improved on hydrophobicity by using LiCl instead of a water-soluble polymer as an additive, has been used for treating the waste water of taurine. The crystalline product has been obtained from the waste water by the membrane distillation-crystallization technique. The results have shown good prospects for a membrane distillation application for treatment of industrial waste water.

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A pre-column derivatization method for the sensitive determination of aliphatic amines using the labeling reagent 1,2-benzo-3,4-dihydrocarbazole-9-ethyl chloroformate (BCEOC) followed by HPLC with fluorescence detection and APCI/NIS identification in positive-ion mode has been developed. The chromophore of 2-(9-carbazole)-ethyl chloroformate (CEOC) reagent was replaced by the 1,2-benzo-3,4-dihydrocarbazole functional group, which resulted in a sensitive fluorescence derivatizing reagent, BCEOC, that could easily and quickly label amines. Derivatives were stable enough to be efficiently analyzed by HPLC and showed an intense protonated molecular ion corresponding m/z [M + H](+) with APCI/MS in positive-ion mode. The collision induced dissociation of the protonated molecular ion formed characteristic fragment ions at m/z 264.1, m/z 246.0 and m/z 218.1, corresponding to the cleavages of CH2CH2O-CO, CH2CH2-OCO, and N-CH2CH2O bonds. Studies on derivatization conditions demonstrated that excellent derivatization yields close to 100% were observed with a 3 to 4-fold molar reagent excess in acetonitrile solvent, in the presence of borate buffer (pH 9.0) at 40 degrees C for 10 min. In addition, the detection responses for BCEOC derivatives were compared with those obtained with CEOC and FMOC as labeling reagents. The ratios I-BCEOC/I-CEOC and I-BCEOC/I-FMOC were, respectively, 1.40-2.76 and 1.36-2.92 for fluorescence responses (here, I was the relative fluorescence intensity). Separation of the amine derivatives had been optimized on an Eclipse XDB-C-8 column. Detection limits calculated from an 0.10 pmol injection, at a signal-to-noise ratio of 3, were 18.65-38.82 fmol (injection volume 10 mu L for fluorescence detection. The relative standard deviations for intraday determination (n = 6) of standard amine derivatives (50 pmol) were 0.0063-0.037% for retention times and 3.36-6.93% for peak areas. The mean intra-and inter-assay precision for all amines were <5.4% and 5.8%, respectively. The recoveries of amines ranged from 96 to 113%. Excellent linear responses were observed with correlation coefficients of >0.9994. The established method provided a simple and highly sensitive technique for the quantitative analysis of trace amounts of aliphatic amines from biological and natural environmental samples.