制浆造纸废水深度处理技术SR-AOPs

<正>采用由高级氧化塔、离子沉淀池、V型砂滤池组成的基于亚铁离子(Fe~(2+))活化过硫酸盐(PS)产生硫酸根自由基(SO)的高级氧化工艺(SR-AOPs),对CODCr浓度为85~110mg/L的制浆造纸废水二级出水进行深度处理。在PS用量1.5 mmol/L、Fe~(2+)用量2.25 mmol/L、     

Fenton法处理造纸废水反渗透浓水的研究

采用Fenton法处理造纸反渗透(RO)浓水,通过正交实验确定了Fenton反应各种因子的影响大小,探讨了 H2O2浓度、Fe2+浓度、反应时间和体系pH值等条件对CODCr去除效果的影响,实验结果表明,采用Fenton高级氧化法处理RO浓水,当体系pH值为4、H2O2浓度为5 mmol/L、Fe2+浓度为2.5 mmol/L、反应时间1.5h时,CODCr去除率可以超过60％,出水CODCr可降低至100mg/L以下,可满足造纸废水排放标准的要求.     

IC-氧化沟-Fenton法处理废纸造纸废水工程实例

天津某造纸厂采用内循环(IC)反应器-表面曝气氧化沟-Fenton氧化法工艺处理废纸造纸废水,处理规模为25000 m3/d。运行结果表明,此工艺能有效处理废纸造纸废水,出水pH值≤7.2、CODCr≤52 mg/L、BOD5≤10 mg/L、SS≤8 mg/L,出水水质达到GB 3544—2008制浆造纸工业水污染物排放标准的要求。     

造纸中段废水深度处理技术研究

采用"磁预处理+催化聚合+絮凝+快速滤池"的组合工艺深度处理造纸中段废水,重点探讨了催化聚合反应机理及其运行参数.结果显示:在进水CODCr为268mg/L、色度为260倍的条件下,当m(H2O2)∶m(催化聚合剂)=1∶3,催化聚合剂的加入量150mg/L,絮凝剂Al2(SO4)3加入量为250mg/L时,最终出水的CODCr在50mg/L左右,色度在10倍以内,CODCr和色度的去除率分别为85%和96%.     

微电解与Fenton氧化联合降解印染退浆废水研究

本研究采用改性微电解材料与Fenton氧化、混凝工艺联合处理印染退浆废水。研究结果表明:微电解/Fenton/混凝为最佳组合工艺,出水B/C为0.44。利用该工艺处理COD_(Cr) 5315 mg/L、PVA 0.68 g/L、B/C 0.10的印染退浆废水,废水pH调至4、微电解材料一次投加量465 g/L、停留时间60 min,并测定微电解出水Fe2+含量,以确定在最佳Fenton反应条件(n(H_2O_2)/n(Fe~(2+))=15∶1,pH=4,反应1 h)下30%H_2O_2投加量。将Fenton反应出水pH调至8,利用残余的Fe~(2+)、Fe~(3+)进行混凝沉淀30 min,然后生化3 d,印染退浆废水的CODCr去除率达到96.65%,PVA去除率达到86.76%,符合印染污水间接排放标准。     

IC厌氧反应器-改良型氧化沟-浅层气浮工艺处理制浆造纸废水

采用IC厌氧反应器-改良型氧化沟-浅层气浮工艺处理制浆造纸废水,介绍和分析了整个工艺的主要构筑物及其调试运行方法.当进水CODCr为4000 mg/L、BOD5为1350 mg/L、SS为2000mg/L时,出水CODCr,≤60 mg/L、BOD5≤20 mg/L、SS≤30 mg/L,达到GB3544-2008造纸工业水污染物排放标准的污染物排放限值.     

基于硫酸根自由基的高级氧化技术深度处理造纸废水的研究

采用零价铁(ZVI)活化过硫酸钠(PS)产生硫酸根自由基的高级氧化技术处理造纸废水二级出水(CODCr为160 mg/L,色度为200度),考察了常温下pH值、ZVI用量、PS用量等因素对CODCr降解率及色度去除率的影响,并对其降解过程动力学进行了探讨,初步确定了硫酸根自由基氧化降解造纸废水的工艺条件,通过采用GC-MS检测分析了废水处理前后的物质变化情况。结果表明,在酸性至中性条件下,硫酸根自由基皆可有效降解有机污染物;在ZVI用量为8 g/L、PS用量为4 g/L时,室温条件下反应3h后,初始pH值为3和未调节pH值废水的CODCr降解率分别达到57.5%和34.2%,色度去除率分别达到83%和89%;通过GC-MS检测分析可知二级出水中含35种有机污染物,经过硫酸根自由基氧化降解后废水中苯类物质得到了一定的降解,相对含量有一定的变化,但种类基本没变。     

Fe0-H2O2法深度处理草类制浆造纸中段废水

采用Fe0-H2O2法对制浆造纸中段废水二级处理后的出水进行了深度处理,考察了pH值、Fe/C比、H2O2投加量和载气等不同的操作条件,结果表明:在pH值为3.0、Fe/C(体积比)为2、H2O2投加量为50 mg/L的条件下对污染物去除有利,温度能够加快反应速度;载气不仅能够提高反应效率,且节省H2O2用量。Fe0-H2O2工艺对中段废水的色度去除率超过98%、对CODCr的去除率在77%以上,紫外吸收光谱表明该工艺可有效去除或降解氯化木素。     

废纸制浆造纸废水深度处理中型试验

采用"磁化+两级反应沉淀"工艺深度处理废纸制浆造纸废水,处理规模为600m3/d的中型试验结果表明,该处理系统在进水CODCr92～131mg/L、色度55～65倍、电导率2387～2527μS/cm、总硬度314～347mg/L的情况下,出水水质稳定,出水CODCr44～57mg/L、色度在5～10倍、电导率1428～1514μS/cm、总硬度122～138mg/L,出水水质满足《制浆造纸工业水污染物排放标准》(GB3544-2008)中"水污染物特别排放限值"要求。同时,废水中有机污染物及电导率、总硬度高效去除,可有效拓展废水的回用途径。     

水解酸化-接触氧化处理造纸中段废水

在实验室采用简单预处理-水解酸化-生物接触氧化工艺对麦草制浆造纸中段废水进行模拟研究,以确定厌氧、好氧生化反应器的最佳运行参数和运行影响因素.结果表明,采用本工艺处理CODCr值为2400mg/L的造纸中段废水,出水达到国家GB 3544-2001排放标准.     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.