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1.
周耘  武书彬 《中国造纸》2019,38(5):75-81
以广州造纸集团有限公司经Fenton法处理废水后的污泥为原料,采用酸浸还原回收Fenton污泥中的Fe,进一步制备高效絮凝剂聚合硫酸铁(PFS)。研究表明,Fenton污泥自然沉降至固含量8%~9%时,先用硫酸中和反应2 h,再加铁屑还原反应2 h,可制备质量分数为25. 0%~26. 7%的硫酸亚铁(FeSO_4)溶液;该溶液经氯酸钠氧化,成功制备出盐基度为10. 8%的聚合硫酸铁(PFS)。并初步评价了所制备的PFS对广州造纸集团有限公司废水处理系统厌氧出水的絮凝效果。结果表明,当PFS用量为5 mL/L时,出水COD_(Cr)可降至260 mg/L,COD_(Cr)去除率达71. 0%。  相似文献   

2.
以改性玉米淀粉、二甲基二烯丙基氯化铵(DMDAAC)与丙烯酰胺(AM)为原料,采用接枝聚合法制备两性废水处理助剂,并用于制革综合废水混凝-接触氧化法的后期处理.结果表明:反应温度50℃、反应时间4h、原料摩尔比n(AM)∶n(DMDAAC)=1∶3、引发剂用量2×10-4mol/kg时,该处理剂的接枝效率可达93.38%,制得的产品能显著降低制革废水色度和具有良好的絮凝效果.  相似文献   

3.
采用PAC-PAM絮凝法、Fenton氧化法对栲胶实际废水进行了处理。通过对其模拟废水进行单因素试验并确定各反应的最佳条件。将确定的最佳反应条件应用于栲胶废水的絮凝-Fenton氧化处理。结果表明,絮凝试验的最佳反应条件为:PAC投加量2.0 g/L,PAM投加量20 mg/L,进水pH=7,搅拌速度120 r/min,搅拌时间40 min。Fenton氧化试验的最佳反应条件为:反应时间40 min,初始pH=3,H_2O_2投加量1.64 mL/L,n(Fe~(2+))∶n(H_2O_2)=1∶3;栲胶废水通过絮凝处理后,出水COD的去除率达到70.0%左右,色度去除率达到93.8%。经Fenton氧化后,COD去除率达到约88.7%,出水COD为180 mg/L左右,色度为8倍。满足了国家污水综合排放标准(GB 8978-2002),且Fenton氧化法处理成本较低,满足实际应用的可行性。  相似文献   

4.
以Al-Zr-SiO_2固体酸为催化剂制备环氧大豆油,考察反应时间、催化剂用量、反应温度、n(H_2O_2)∶n(双键)对环氧化反应的影响,并通过响应面试验对环氧化反应工艺条件进行优化。得到环氧化反应最佳工艺参数为,大豆油∶甲酸∶过氧化氢=1∶0.5∶2.5(摩尔比),Al-Zr-SiO_2固体酸催化剂用量为0.8%,反应温度为70℃,反应时间为4 h,在该条件下所得大豆油的环氧值为6.57%。  相似文献   

5.
马明玉  谢益民  洪卫 《中华纸业》2011,32(18):29-32
采用铁系仿酶Fe-多元羧酸复合物(简称Fe—cA)预处理二沉池出水,然后分别用聚合硫酸铁(PFS)、Al2(SO4)3、PAC三种絮凝剂进行絮凝处理。通过检测废水的COD、色度和TOC等指标,发现PFS的效果最佳。确定最优条件为:废水pH值6~7,PFS的投放量为200mg/L,PAM用量2mg/L,沉降时间3h。最终出水COD可降至80mg/L,色度为30倍,TOC降低至20mg/L。达到了饰4浆造纸工业水污染物排放标准》(GB3544-2008)的排放要求。铁系絮凝剂PFs用于造纸废水深度处理效率高、成本低、绿色环保,具有很好的应用前景。  相似文献   

6.
以玉米淀粉和丙烯酰胺为原料、硝酸铈铵为引发剂,通过接枝共聚反应对淀粉进行改性,合成了淀粉/丙烯酰胺接枝共聚物(SAM),即改性淀粉絮凝剂。将合成的SAM絮凝剂用于造纸废水絮凝处理,讨论了SAM絮凝剂用量、废水的温度和p H值等因素对处理效果的影响。研究显示,在丙烯酰胺与淀粉质量比为2∶1、引发剂浓度2.0 mmol/L、反应温度40℃、反应时间3 h、反应体系p H值4.0的条件下,SAM絮凝剂合成反应的接枝率达到68.5%;红外光谱分析表明丙烯酰胺成功接枝在玉米淀粉基质中。将SAM絮凝剂用于处理混合造纸废水,当SAM絮凝剂用量为12 mg/L、废水p H值7~9、温度30℃条件下,CODCr去除率为88.4%,浊度去除率为91.2%,BOD5去除率为85.5%,处理后废水透光率为93.3%。  相似文献   

7.
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(Fe2+)活化过硫酸盐(PS)产生硫酸根自由基(SO4-·)的高级氧化工艺(SR-AOPs)深度处理制浆造纸废水二级出水(CODCr为85~110 mg/L).结果表明,SR-AOPs对制浆造纸废水二级出水有很好的处理效果,最优工艺条件为:PS用量1.5 mmol/L,Fe2+用量2.25 mmol/L,n(PS)∶n(Fe2+) =2∶3.在该条件下,出水CODCr为31.2 mg/L,CODCr去除率达到70%,出水SS低于5 mg/L,SO42-浓度为203.5 mg/L,出水水质达到GB3544-2008制浆造纸废水排放标准,废水处理成本约为2.831元/t.  相似文献   

8.
张安龙  李颖  周瑜 《中华纸业》2006,27(5):68-70
利用漂白粉和Fenton试剂(H2O2/Fe2+)处理碱法草浆中段废水.实验表明,漂白粉的最佳工艺条件为:用量1000mg/L,反应前调节pH值为2.0,反应时间2n.Fenton试剂的最佳工艺条件为:H2O2/Fe2+为6:1,H2O2用量为150mg/L,pH值为5.0,反应时间3~4h.  相似文献   

9.
采用絮凝-Fenton氧化处理E段漂白废水。通过正交实验确定了最佳操作参数。Al2(SO4)5-Fen%on氧化配合处理E段漂白废水的最佳操作条件为:Al2(SO4)3用量0.6g/L,氧化反应的pH值为5,H2O2用量1.Og/L,FeSO4用量0.8g/L,在此条件下废水COD的去除率可达90.64%。CPAM-Fenton氧化配合处理E段漂白废水的最佳操作条件为:CPAM用量0.8mg/L,氧化反应pH值6,H202用量1.5g/L,FeSO4用量1.2g/L,在此条件下废水COD的去除率可达82.43%。  相似文献   

10.
徐长绘 《针织工业》2014,(12):46-50
介绍了无机混合酸改性黏土的制备方法,通过正交试验确定了改性黏土制备的最佳工艺。并将改性黏土用于印染废水处理,测试并分析了初始p H值、改性黏土加入量、废水浓度以及温度对废水脱色率的影响。同时,对改性黏土进行吸附动力学、吸附热力学研究。结果表明,改性黏土制备的最佳工艺为:固液比1∶10,加热温度100℃,加热时间为60 min,搅拌速度为1 000 r/min;废水处理最佳工艺为:50m L自制印染废水中(20 mg/L亚甲基蓝),改性黏土的加入量为150 mg、p H值为9~11、静置沉淀时间为2h、废水初始浓度低于30 mg/L、反应温度为30~50℃;吸附符合二级动力学模型和Langmuir等温吸附曲线,吸附过程为吸热、自发的过程。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

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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.  相似文献   

18.
<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the  相似文献   

19.
《印刷工业》2014,(11):95-95
According to Printing and Printing Equipment Industries Association of China(PEIAC)'s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.  相似文献   

20.
《印刷工业》2014,(8):103-103
正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press  相似文献   

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