光催化氧化-UASB-A/O处理食品添加剂废水

针对添加剂废水中含有少量乳链菌肽及高含量Cl-的特点,采用“光催化氧化-上流式厌氧污泥床-A/O”组合工艺对废水进行处理.经过5个月的调试,在系统进水COD为12 680 mg·L-1、BOD5为5 213 mg·L-1、NH3-N的质量浓度为121 mg·L-1的情况下,出水COD为97 mg· L-1、BOD5为27 mg· L-1、NH3-N的质量浓度为13 mg·L-1,去除率分别为99.2％、99.5％和89.3％,排水水质达到了GB 8978- 1996规定的第2类污染物最高允许排放一级标准.     

物化-接触氧化-过滤工艺处理漂染废水工程实例

采用物化-接触氧化-过滤工艺处理以活性染料为主的漂染废水,设计规模为10000 m3·d-1,进水水质为COD480 mg·L-1,BOD5 200 mg·L-l,P(SS)300 mg·L-1,色度300倍,pH 8～10:经该工艺处理后,出水水质为COD≤90 mg·L-1,BOD5 28 mg·L-1,ρ(SS)29 mg·L-1,色度39倍,pH 8.1,达到了国家污水综合排放标准(GB8978-1996)-级排放标准的要求.     

A2/O工艺处理混合污水脱氮中试研究

采用A2/O工艺处理生活污水和粪便的混合污水,进行了不同HRT、DO、混合液回流比和污泥回流比等条件下的脱氮效果的研究,进行了6种不同工况下的脱氮和有机物去除效果的研究.结果表明,当好氧池水力停留时间(HRT)为5 h、好氧池DO为3 mg·L-1、混合液回流比R为120%和污泥回流比r为80%时,A2/O工艺能获得较好的脱氮效果和有机物去除效果.     

低温城市生活污水再生全流程中A/O高效除磷研究

研究了低温条件下污水再生全流程中A/O生物除磷系统的稳定运行.结果表明,在低温条件下(10～14℃),不同污泥负荷对出水效果影响显著,在系统NSCOD(COD污泥负荷)为0.6 kg·kg-1·d-1,DO质量浓度为1～2 mg·L-1 时,系统仍有较好的处理效果,出水ρ(TP)＜0.7 mg·L-1,除磷率达到84％～96％,出水COD＜60 mg·L-1,COD去除率达到80％～88％;试验发现A/O系统进水碱度、VFA充足,无需外投加碱度和VFA即可获得较好的除磷效果;pH、ORP能够反映聚磷菌的活性,pH是聚磷菌活性的表征,pH较高时磷的去除效果显著,聚磷菌活性高;随着磷的去除效果不断增强,聚磷菌的活性逐渐升高,厌氧池内ORP值降低;A/O除磷系统可以实现对污水中氮素最大限度的保留,实现亚氮、硝氮的最小积累,为后续的自养脱氮提供稳定适宜的进水.     

宾县生活污水处理厂主要构筑物设计

本设计主要任务是根据宾县生活污水的水质水量等实际情况,选择CASS工艺,做主要构筑物的设计计算。该污水厂的污水处理流程为:从进水到格栅,沉砂池,进入CASS反应池,消毒接触池,最后出水;污泥的流程为:从CASS反应池排除的剩余污泥首先进入浓缩池,进行污泥浓缩,然后将经过浓缩的污泥送至贮泥池,经过压缩机之后处置。要求处理的水质达到《城镇污水处理厂污染物排放标准》GB18918-2002中的一级(B)排放标准,其中进水指标:BOD5=200mg·L-1,COD=300mg·L-1,NH3-N=30mg·L-1;出水指标:BOD520mg·L-1,COD60mg·L-1,NH3-N8mg·L-1。     

改良型A2/O工艺在生活污水处理中的应用

采用改良型A2/O工艺处理陕西科技大学西安校区生活污水,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COD≤60 mg· L-1、ρ(TN)≤20 mg· L-1、ρ(TP)≤1.0mg·L-1、ρ(SS)≤20 mg·L-1、BOD5≤20 mg·L-1,出水水...     

组合填料A/O工艺处理有毒难降解腈纶废水的研究

以腈纶废水为研究对象,考察了水力停留时间、溶解氧、硝化液回流量等因素对组合填料膜A/O工艺处理腈纶废水的影响.结果表明,当停留时间为14h、溶解氧质量浓度为3.5 mg·L-1、硝化液体积回流比为200％时,COD去除率达到60％以上,TOC去除率达到60％以上,BOD5去除率可达90％以上,特征污染物DMAC(二甲基...     

EGSB反应器处理高浓度豆制品废水的研究

在中温(32～37℃)条件下,采用小试规模膨胀污泥床(EGSB)反应器处理高浓度豆制品废水(污水COD为1000～13000mg·L-1),连续运行180d,研究了进水COD、有机负荷(OLR)以及水力停留时间(HRT)等因素对废水处理效果的影响.研究利用好氧污泥接种成功培养出了高活性的厌氧颗粒状污泥.结果表明,EGSB反应器处理高浓度食品废水能够达到很好的效果,当进水COD有机负荷为2～6.75 kg·m3·d-1,HRT为48 h时,COD、BOD,去除率为85%左右;当进水COD为10000mg·L-1,最佳HRT为24h,此时相对应的OLR约为10-2kg·m-3d·d-1.稳定运行期间,厌氧反应器消耗每克COD的CH4产率为0.08～0.14 L·g-1,甲烷含量为60%～75%.试验达到了较好的处理效果和较高的产气率,表明应用EGSB处理高浓度豆制品废水是高效、可行的.     

小型一体化MBR系统处理"农家乐"污水实例

采用小型一体化MBR系统处理"农家乐"污水,设计规模为4.0 m3·d-1.在进水COD、BOD5分别为400、200 mg·L-1,SS、NH3-N、动植物油的质量浓度分别为120、40、25 mg·L-1,pH为6～9时,处理后出水的COD,BOD5分别为40.8mg·L-1,SS、NH3-N、动植物油的质量浓度分别为2.4、1.6、2.5nag·L-1,pH为6～9.出水水质达到污水综合排放标准(GB8978-1996)中一级排放标准.     

O/A/O工艺处理化工综合含氮废水运行优化研究

采用初曝池-兼气池-好氧池( O1/A/O2)工艺处理化肥、季戊四醇生产综合含氮废水,在进水COD、NH4+-N的质量浓度平均分别为624和59.3 mg·L-1时,出水COD在100 mg·L-1以下,平均为34.5 mg· L-1,去除率达93.2％;出水氨氮的质量浓度在15 mg·L-1以下,平均为0.8 mg·L-1,去除率高达98.7％;达到了GB 8978- 1996的一级标准.分析了系统反硝化能力较差、TN去除效率较低的原因,提出应减小硝化液回流比、适当调低O1池DO含量、充分利用厂区季戊四醇废液作为外加碳源等措施.     

氢气纯度分析方法准确性的探讨

ONACCURACYOFANALYSISOFOFHYDROGEN1前言我公司目前应用的氢气纯度分析方法有两种,一种是爆炸反应法,另一种是焦性没食子酸吸收法。几年来,人们对两种分析方法的准确性曾有过褒贬不一的评论。这里我们也谈谈自己粗浅的观点。2爆炸法测定氢气纯度一定量的氢气样品与适量的空气之均匀混合物因反应后生成液体水而引起气体体积减少,减少的体积等于参加反应气体体积之和。其中l／3为氧气,2／3为氢气。根据氢气取样量和反应前后混气体体积之差,以及氢气在反应中的体积比例关系,可计算出样品的氢气纯度。计算公式式中：A一混…     

COMPARISON OF METHODS OF ANALYSIS OF GYPSUM1

The different analytical methods proposed for the evaluation of gypsum have been subjected to an experimental test. A combination method, consisting of a fusion with KHCO₃ and determination of CaO by KMnO₄ titration, the SO₃ by Andrews method of titration of BaCrO₄ has been found to give very reliable results with the least consumption of time.     

SEDIMENTATION OF BINARY MIXTURES OF PARTICLES OF UNEQUAL DENSITIES AND OF DIFFERENT SIZES

A model is developed for the sedimentation from a suspension of two particle species of unequal densities and of different sizes. The composition and the thickness of various layers in the sediments are predicted using graphical and analytical methods. The model predictions were in excellent agreement with experimental results, when the particle size ratio was ≥ 108. When size ratio of the particles was 2.60 and 4.31 the agreement occurred in about 50 percent of the cases.     

HEASUREHENT OF INSTANTANEOUS RATES OF LOSS OF VOIATILE COMPOUNDS DURING DRYING OF DROPS

A novel technique serves to monitor instantaneous rates of loss of a volatile solute from a suspended drop during drying. A highly sensitive electron capture detector is used to monitor concentrations of SF6 released into a flowing gas stream from a suspended, drying drop. Simultaneously, the appearance and morphological development of the drop are monitored with a video camera. This provides the wherewithal of relating instantaneous rates of loss of the volatile solute to particular events during the development of particle morphology.

Initial experiments have been carried out with drops of aqueous solutions of glucose, sucrose, maltodextrin and coffee extract. The results clearly display the onset of the volatiles-retentive selective diffusion phenomenon. There is also substantial loss of the volatile component later in the drying process, when the drops undergo repeated ex ansion, bursting and cratering due to the formation of internaf bubbles. These experiments appear to be the first quantitative demonstration of major losses accompanying changes in drop morphology.     

茶多酚提取方法进展

本文综述了国内外现有茶多酚提取方法的现状以及近期的研究进展，并对其优缺点进行了评价。这将有助于中低档茶的综合利用和茶多酚的进一步开发应用。     

几种针状焦性能对比

针状焦分石油系和煤系两大类,这主要取决于针状焦的原料来源。在同一系列中由于原料不同和工艺条件不同 ,针状焦的各自性能也不相同。针状焦是生产超高功率石墨电极和高功率石墨电极的主要原料 ,针状焦的性能对石墨电极的质量有至关重要的影响。所以对针状焦性能以及其对石墨电极质量影响的研究十分必要的。以下是常用的几种进口针状焦和国产针状焦的性能对比。１原料性能分析对比原料试样包括４种针状焦 ,其中两种为进口针状焦：三菱针状焦和新日化针状焦;另两种为国产针状焦：鞍山针状焦和锦州针状焦。其中除锦州针状焦是石油系针状焦外…     

ANALYSIS OF RECENT MEASUREMENTS OF THE VISCOSITY OF GLASSES

Viscosity of Simple Soda-Silicate 500° to 1400°C Comparison of the results given by English with those of Washburn, Shelton and Libman, indicates a discrepancy in the absolute values of log₁₀ viscosity amounting to 0.6, those of Washburn et al., being relatively too high. If correction for this is made, the isothermal curves of log₁₀ viscosity as a function of soda content are smooth up to 50% Na₂O, showing no inflection. The observations as a function of temperature T are all represented within accidental error by an equation of the type where all three constants vary regularly with the composition. Change of Viscosity of Glass (6SiO₂, 2Na₂O) due to Molecular Substitution of CaO, MgO and Al₂O₃ for Na₂O The effect is clearly brought out by plotting (from the results of English) the change of log₁₀η due to the substitution as a function of temperature. The curves each show a sharp bend at a temperature between 840° and 1050°C, which is designated the aggregation temperature T_a. If we divide these curves by the corresponding percentage substituted, we get curves for each oxide which are straight and parallel below the aggregation temperatures, the slopes (increase of change of log₁₀η per 100°C) being −0.056 (CaO), −0.055 (MgO), −0.018 (A1₂O₃) per per cent oxide substituted. For substitution of 1/2 molecule the slopes are −0.325 (CaO), −0.23 (MgO) and −0.18 (Al₂O₃) per 100°. At the aggregation temperature the change of log₁₀η per per cent is a minimum, 0.03 to 0.06 for CaO, 0.12 for MgO, 0.07 for Al₂O₃. Evidence of Aggregation in Glasses, from viscosity Measurements The sharp bends in the plots of change of log₁₀η due to substitution of an oxide for Na₂O, suggest the beginning of molecular aggregation at these temperatures. These aggregation temperatures are close to the devitrification temperatures, but the effect on the viscosity curves cannot be due to actual devitrification since it does not change with time. Taking the aggregation temperatures as equal to devitrification temperatures, additional isotherms are roughly sketched into the equilibrium triangle of the system Na₂O-CaO-SiO₂. Change of Viscosity of Glass (4SiO₂, 2Na₂O) due to of Substitution of B₂O₃ for SiO₂ The change of log₁₀η (from the results of English) is plotted as a function of temperature, and also the change of log₁₀η per per cent B₂O₃. The curves are more complex than for the substitution for Na₂O.     

环氧树脂羟基值测定方法的研究

利用乙酸酐、吡啶和浓硫酸混合的乙酰化试剂测定环氧树脂中羟基值含量的方法具有操作简便、滴定终点明显和分析结果误差小等优点。     

骑式摩托车油箱喷涂工艺的改进

面对日益激烈的市场竞争,摩托车油箱外观质量越来越成为影响销售的因素之一。文章介绍了改进工艺后的油箱涂装,该涂装体系提高了油箱外观的丰满度,降低了油箱涂装的生产成本。     

聚酰亚胺的合成法

本文评述了缩聚型聚酰亚胺的主要合成方法和近年来国际上在合成中所做的探索。