供气式低压射流曝气氧化沟废水处理工程的调试

介绍FAS-Jet供气式低压射流曝气系统的改良型氧化沟对瓦楞纸废水的处理工艺,以氧化沟为核心的系统的处理能力15000m3·d-1,并对整个调试过程进行了详细的介绍和分析。运行结果表明,该工艺设计合理,运行稳定可靠,出水CODCr≤120mg·L-1,SS≤50mg·L-1,BOD530mg·L-1,出水水质达到造纸工业水污染物排放国家标准(GB3544-2008)。     

混凝强化微电解工艺深度处理造纸中段废水

采用混凝强化微电解工艺深度处理造纸中段废水,通过考察废水CODCr、色度的去除效果,得到其最佳工艺条件:常温下,pH值4.0,用铁量40g·L-1,活性炭用量8g·L-1,反应时间60min,PAC用量120mg·L-1,PAM用量1mg·L-1。结果表明:出水色度36倍,去除率90%;CODCr96mg·L-1,去除率66%,达到造纸行业废水排放标准。     

低压射流曝气氧化沟系统处理苇浆造纸中段废水

采用供气式低压射流曝气系统改良型氧化沟工艺处理苇浆造纸中段废水,对整个工艺及调试运行过程进行了详细介绍。实际运行结果表明,该工艺设计合理,运行稳定可靠,总排放口出水CODCr≤150mg/L、SS≤50mg/L、BOD5≤30mg/L,出水水质可达到《造纸工业水污染物排放标准》(GB3544—2008)的要求。     

粉煤灰联合混凝剂处理废纸造纸废水的试验

以PAC为混凝剂、PAM为助凝剂联合处理经过粉煤灰预处理后的造纸废水,探讨粉煤灰协同PAC、PAM处理造纸废水的工艺。研究结果表明:在中性条件下,粉煤灰用量150g·L-1,搅拌1h,对造纸废水处理效果最为明显,上清液再用含铝量10%的PAC和1g·L-1的PAM处理,投加量分别为1mL·L-1和1.5mg·L-1,出水CODCr小于100mg·L-1,达到造纸行业排放标准。     

OCC造纸废水处理工程实例

介绍某纸业公司采用预处理-IC厌氧反应器-曝气池-Fenton工艺处理OCC造纸废水的情况。工程实践表明,该工艺处理效果良好,出水水质pH值≤7.2,COD_(Cr)≤55 mg·L~(-1),SS≤9 mg·L~(-1),出水指标达到《制浆造纸工业污染物排放标准》(GB 3544-2008) 的排放标准要求。     

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。     

宣纸生产中黑液的物化处理

宣纸是我国手工纸中最著名的一种,其生产废水中檀皮蒸煮黑液的CODCr浓度相当高,达42000mg·L-1。实验采用微电解-絮凝-吸附的组合工艺对其进行处理,主要考查了各阶段处理的主要影响因素及其处理效果关系。结果表明:经过整个工艺3个阶段的处理,最终出水的CODCr为3481.9mg·L-1,去除率达91.7%,色度为10倍,去除率高达97.5%。这是一个有效的预处理工艺,并能节约大量的稀释用水。     

杨木化机浆制浆造纸废水处理工艺运行实例

以水解酸化-IC-曝气池-混凝沉淀的处理工艺,对某制浆和造纸联合生产企业生产废水进行处理。长期运行数据显示,采用该工艺对此废水进行处理,厌氧去除率可达65%左右,厌氧出水COD平均浓度为3000 mg·L~(-1);好氧单元的去除率80%左右,出水浓度为350 mg·L~(-1);深度处理COD平均去除率80%,平均出水浓度72 mg·L~(-1),可以稳定达到《制浆造纸工业水污染物排放标准》(GB 3544-2008)所要求的排放标准。     

印染废水处理及回用工程实例

采用截留池/水解酸化/好氧生化/混凝沉淀/无阀滤池的组合工艺处理印染水洗废水,工程运行结果表明:进水CODCr≤800 mg/L,SS≤200 mg/L,色度≤200倍,电导率≤3 000μS/cm,处理后出水CODCr≤150 mg/L,SS≤10 mg/L,色度≤15倍,电导率≤3 000μS/cm,系统出水可简单回用于印染前处理(退浆或碱减量)和深色布染色工艺。     

曝气生物滤池对皮革废水中氨氮去除的研究

皮革废水经物化和普通接触氧化处理后往往因为氨氮高而难以达标排放,本文探讨了采用曝气生物滤池(BAF)进一步降解经物化和普通接触氧化后出水中氨氮污染物的可行性及处理效果.研究结果表明,在BAF进水CODcr为200～250 mg·L-1、氨氮为80～100 mg·L-1时,经BAF曝气4 h处理后出水的CODcr和氨氮分别达到86 mg·L-1、10 mg·L-1以下.     

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.     

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.     

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.     

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.     

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.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.