活性炭颗粒载体厌氧同步去除COD和含氮污染物

以活性炭颗粒为填料构建厌氧污水处理系统。以葡萄糖作为单一碳源,当进水中葡萄糖的质量浓度为500 mg/L时,COD的去除率最高为87.9%。系统对NH4+-N和NO3--N的最高去除率分别为60.3%和95.2%;同时出水中NO2--N没有明显的积累,始终低于0.55 mg/L。这表明以活性炭为填料的厌氧污水处理系统能有效降低反硝化菌及其代谢产物对厌氧消化菌的抑制,实现COD和含氮污染物的协同、高效去除。     

废聚苯乙烯泡沫制备颗粒活性炭

研究了以废聚苯乙烯泡沫为原料制备颗粒活性炭的工艺过程。在将聚苯乙烯炭化(600~650℃)后,采用物理活化法(水蒸气)进行了系列实验,活化时间为60 min,活化温度范围800~950℃。实验结果表明,聚苯乙烯炭化物是制备颗粒活性炭的良好原料。不定型颗粒产品灰分低于0.20%,微孔发达,碘值在1200 mg/g以上;定型活性炭比表面积在1400 m2/g以上,碘值达到1100 mg/g。     

Control of bio-regenerated granular activated carbon by spreadsheet modelling

The optimisation of water purification with biological activated carbon (BAC) is described. Procedures are suggested to control biofilm growth and to use bio-indicators to predict TOC (total organic carbon) and COD (chemical oxygen demand) removal efficiencies. Empty bed contact time (EBCT) was a major physical control parameter. Dissolved oxygen (DO), pH and nutrients of the influent were controlled according to the abundance of bacteria, protozoa and rotifers. Numbers of micro-organisms in BAC beds were determined. Certain genera of ciliated protozoa, representing healthy environmental conditions, were employed as biological indicators for system performance during biological regeneration of exhausted granular activated carbon (GAC). There was a strong positive correlation between the abundance of some protozoa in the liquid phase of the BAC bed and COD concentration in the effluent. Mathematical spreadsheet models were constructed to estimate COD removal efficiency of BAC filters with different loading rates, DO, pH, nutrient requirements and populations of micro-organisms. © 1998 SCI     

活性炭工艺去除水中典型药品的效能与机理

药品和个人护理品（PPCPs）因其潜在的环境和健康风险受到了广泛关注。实验选取8种典型药品为对象,采用中试规模的活性炭工艺研究了其去除效果和影响因素。结果表明,活性炭工艺对安替比林、达舒平、舒必利、磺胺甲口恶唑、泰妙菌素和氧苄胺嘧啶等的去除率为50%～90%,对林肯霉素和氨糖美辛的去除率均小于35%。典型药品的去除率受到滤速、有机物和pH等因素的影响,其中,氨糖美辛、林肯霉素和泰妙菌素等的去除率受滤速影响较大;磺胺甲口恶唑的去除率受pH影响较大。有机物对典型药品去除率的影响既有促进作用,又有抑制作用。典型药品的物化性质对其去除行为有重要影响,这有利于从分子水平上认识活性炭工艺对典型药品的去除机理。     

微波辐射下活性炭催化甲烷裂解制氢

采用石英管固定床反应器,在微波加热条件下分别研究了气氛条件、甲烷分压以及铁粉对活性炭催化裂解甲烷的影响,并与传统电加热方式下的甲烷裂解特性进行了对比研究。结果表明,活性炭在不同气氛条件下表现出不同的升温特性,活性炭在氮气和氢气中的升温效果优于甲烷气氛。铁粉的掺入有利于提高活性炭反应温度,从而促进甲烷的转化率。对反应前后的活性炭进行了扫描电镜和比表面积分析,结果表明甲烷裂解后产生的大量积炭覆盖在活性炭表面,导致比表面积和孔容减小,平均孔径增大。进而推测活性炭活性降低的主要原因是由于积炭堵塞了活性炭微孔,减少了甲烷与活性炭微孔中的活性中心位的接触。     

固定化生物活性炭纤维处理餐饮污水

采用固定化生物活性炭纤维技术处理餐饮污水,在原水COD、油的平均质量浓度分别为961、254 mg/L时,经过砂滤、曝气、生物活性炭纤维柱后,COD去除率为84%,油的去除率为91%。试验结果表明:固定化生物活性炭纤维技术对餐饮废水有较好的处理效果,出水水质稳定,可达标排放。     

Kinetics of removal of p-toluene sulphonic acid from concentrated solution by granular activated carbon

The removal of p-toluene sulphonic acid (p-TSA) from concentrated solution by granular activated carbon (GAC) was studied in batch experiments. The first order rate constant was found to be 5.5010 × 10^?5 s^?1 for a solution of 1000 mg dm^?3. In order to establish the rate limiting step the pore and film diffusion coefficients were calculated from the half time equations. Film diffusion was found to be rate limiting. The average value of the external mass transport rate constant was 2.91 × 10^?6 cm s^?1. The adsorption isotherm was adequately described by the Langmuir model and belongs to type ‘H’ of Giles' classification.     

Substrate-inhibited microbiological regeneration of granular activated carbon

A kinetic model of the microbiological regeneration of activated carbon is presented for the case where the adsorbate is inhibitory to the microbial-growth-associated bio-oxidation process. The model is used to predict the regeneration time for specified combinations of microbial species (using growth kinetic constants determined in a carbon-free system) and carbon type (adsorption isotherm). In addition to the foregoing parameters, computer simulations show that the spent carbon adsorbate loading, the carbon mass-to-fermentation broth volume ratio and the inoculum size also have a significant effect on the time required for batch in situ regeneration of a carbon column. Experimental results are given for a granular carbon-phenol-bacteria (P. putida) system at several operating conditions; the observed regeneration times are in good agreement with predicted values. Once-regenerated carbon retained 47 percent of the phenol equilibrium adsorption capacity of fresh carbon. No further loss of adsorption capacity was found for carbon which subsequently was regenerated two more times, i.e., for a total of three sequential microbiological regenerations.     

A comparative adsorption/biosorption of phenol to granular activated carbon and immobilized activated sludge in a continuous packed bed reactor

The potential use of Mowital B30H resin immobilized dried activated sludge as a substitute for granular activated carbon for removing phenol from aqueous solution was examined in a continuous packed bed reactor as a function of flow rate and inlet phenol concentration. The working sorption pH value was determined as 1.0 for both the sorbents, and packed bed sorption studies were performed at this pH value. The maximum specific uptakes, total adsorbed quantities, and total removals of phenol related to the effluent volumes were determined by evaluating the breakthrough curves obtained at different flow rates and different inlet phenol concentrations for each sorbent. At the lowest flow rate of 0.8 mL/min and at the inlet phenol concentration of 500 mg/L, the maximum specific uptakes and total removals of phenol were 84.0 mg/g and 27.6%, respectively, for granular activated carbon and 9.0 mg/g and 9.3%, respectively, for immobilized dried activated sludge. Data confirmed that total removals of phenol decreased with increasing flow rate and inlet phenol concentration for both immobilized dried activated sludge and granular activated carbon systems.     

颗粒活性炭用于盐湖卤水净化脱色的研究

为降低色度对盐化工产品质量的影响,提高盐湖卤水综合利用的产品附加值,采用颗粒活性炭对盐湖卤水净化脱色.通过静态吸附实验,探讨了活性炭的用量、温度、pH对脱色率的影响.研究结果表明:每50 mL卤水加入6 g颗粒炭,在pH=2,90℃下吸附9 h,卤水脱色率达到70%.卤水自身的高离子强度和高粘度使得水分子流动性差,进而严重制约吸附效率的提高.投入大量的吸附剂和延长吸附时间亦能提高吸附效率,但成本也随之增加,在实际应用中意义不大.改善吸附工艺条件是提高吸附效率的关键所在.     

超声波强化活性炭颗粒吸附PFOA和PFOS

研究了20 kHz超声波强化活性炭颗粒吸附不同种类水溶液中全氟辛烷磺酸（PFOS）和全氟辛酸（PFOA）的动力学。结果表明：平衡吸附被证实符合BET多层等温吸附,最大单层吸附容量为qmPFOS>qmPFOA;在PFOS和PFOA初始浓度为50 mg/L时超声波辐照下活性炭颗粒吸附符合表观拟二级动力学关系,平衡吸附容量和起始吸附速率分别为qePFOS>qePFOA和 hPFOS> hPFOA;在去离子水（MQ）中的PFOS和PFOA 最大单层吸附平衡容量qm和平衡吸附容量qe及起始吸附速率h和吸附动力学常数K均大于预处理或未预处理后的垃圾渗滤地表水（Pre-GW和GW）中对PFOS和PFOA的平衡吸附量和吸附动力学常数;20 kHz超声波强化活性炭颗粒吸附PFOS和PFOA效果明显,其吸附动力学常数增强因子为7.7和4.4。     

Sulfate removal from acid mine drainage using polypyrrole-grafted granular activated carbon

A novel method of removing sulfate from acid mine drainage (AMD) water was developed by depositing polypyrrole into the pores of wood-based activated carbon (RGC) using in situ chemical oxidative polarization. This polypyrrole-tailored activated carbon hosted positively charged polypyrrole functionality that offered sorption capacity for sulfate. Specifically, in batch tests, the polypyrrole-grafted RGC achieved a sulfate loading of 48 mg/g, this being 8 times higher than for pristine RGC. Rapid Small Scale Column Tests appraised the polypyrrole-tailored RGC for removing 773 mg/L sulfate from AMD water. The more favorably tailored carbon removed sulfate to half-breakthrough at 24 bed volumes (BV). This compared to 1.5 BV for pristine activated carbon. Per mass and charge balance, 9% of the nitrogen in the polypyrrole functionality was active for capturing sulfate. On this tailored carbon, the nitrogen content was 12.9%, as characterized by X-ray photoelectron spectroscopy. With this polypyrrole tailoring, the carbon’s pore volume distributions diminished to one-third, as characterized by argon adsorption.     

Adsorption of flavour esters on granular activated carbon

This article reports on the liquid phase adsorption of flavour esters onto granular activated carbon. Ethyl propionate, ethyl butyrate, and ethyl isovalerate were used as adsorbates, and Filtrasorb 400 activated carbon was chosen as the adsorbent. Sips, Toth, Unilan, and Dubinin‐Radushkevich isotherm equations which are generally used for heterogeneous adsorbents were used to fit the data. Although satisfactory in fitting the data, inconsistency in parameter values indicated these models to be inadequate. On the other hand the Dubinin‐Radushkevich model gave more consistent and meaningful parameter values and adsorption capacities. By employing the Dubinin‐Radushkevich equation, the limiting volume of the adsorbed space, which equals the accessible micropore volume, was determined, and found to correlate with the value from carbon dioxide adsorption.     

粘结剂在褐煤制备粒状活性炭中的应用

考察了在褐煤半焦压块活化制备活性炭的过程中,煤焦油、废蜜糖、淀粉和纤维素四种粘结剂在成型造粒以及产品性能方面的不同作用,提出用无污染物质作为粘结剂是褐煤制备活性炭的发展方向。     

Trace element distributions of a granular activated carbon

Elemental distributions obtained by energy dispersive X-ray fluorescence (EDXRF) analysis, combined with scanning electron microscopy (SEM), are presented for used and virgin samples of a commercial granular activated carbon (GAC) Calgon F400 manufactured from bituminous coal. Distributions of Al, Si, K and Fe reveal the presence of large inclusions of a clay mineral such as illite, approximately 10–360 μm in diameter. We also find mineral inclusions of Fe alone, about 6–80 μm in diameter. The elemental distributions for S are diffuse and do not indicate the presence of iron sulfide compounds, although pyrite is the major iron mineral in bituminous coal feedstocks used for Calgon F400. The Mössbauer spectrum of Calgon F400 confirms the presence of iron oxides and iron metal, as probable products of pyrite during manufacture of the GAC. In samples of F400 used for potable water purification, Cl and Ca are characterized by diffuse distributions; results of quantitative EDXRF analysis indicate these elements are associated with compounds adsorbed from water on the surface of Calgon F400.     

Sulfur removal from model diesel fuel using granular activated carbon from dates’ stones activated by ZnCl2

Samples of granular activated carbon (GAC) were produced from dates’ stones by chemical activation using ZnCl₂ as an activator. Textural characteristics of GAC were determined by nitrogen adsorption at 77 K along with application of BET equation (Brunauer, Emmett and Teller) for determination of surface area. Pore size distribution and pore volumes were computed from N₂ adsorption data by applying the nonlinear density function theory (NLDFT). FT-IR spectra of GAC samples were also obtained to determine the functional groups present on the surface. GAC samples were used in desulfurization of a model diesel fuel composed of n-C₁₀H₃₄ and dibenzothiophene (DBT) as sulfur containing compound. More than 86% of DBT is adsorbed in the first 3 h which gradually increases to 92.6% in 48 h and no more sulfur is removed thereafter. The adsorption data were fitted to both Freundlich and Langmuir equations to estimate the adsorption parameters. The optimum operating conditions for GAC preparation based on high adsorption capacity are T_carb = 700 °C, θ_carb = 3.0 h and R = 0.5. Moreover, the efficiency of sulfur removal by GAC is reduced when applied to commercial diesel fuel. Finally, linear regression of experimental data was able to predict the critical pore diameter for DBT adsorption (0.8 nm) and validating the reported impact of average pore diameter of activated carbon on the adsorption capacity.     

微生物反应器处理含镍废水的研究

从受污环境中分离筛选出对Ni~(2+)有去除活性的产朊假丝酵母菌y188。采用响应曲面法对游离细胞去除废水中Ni~(2+)的条件进行优化。在35℃,pH=7.0,130 r/min振荡培养25 min的条件下,y188细胞对模拟废水中Ni~(2+)的去除率达到98.49%。以y188为菌种、废弃煤渣颗粒为载体组建固定化细胞生物反应器。该反应器在15—45℃,pH=2—8的条件下均保持良好的除Ni~(2+)活性,对Ni~(2+)质量浓度为10 mg/L的模拟废水可连续处理8批,Ni~(2+)的去除率保持在91%以上,对Ni~(2+)质量浓度为13.74 mg/L的实际废水连续处理6批,Ni~(2+)的去除率保持在93%以上。出水Ni~(2+)质量浓度均1.0 mg/L,达到国家电镀污染物排放标准。显微观察结合解吸实验表明,y188细胞在30 min内对废水中Ni~(2+)的去除主要是吸附除Ni~(2+)。     

蔗渣活性炭去除糖蜜酒精废水COD的实验研究

通过单因素与正交实验,研究了蔗渣活性炭处理糖蜜酒精废水的工艺条件及其影响因素.结果表明,最佳工艺条件为蔗渣活性炭投加质量0.30 g、吸附时间120 min、溶液的pH=7.3(中性)和温度为30℃(常温),在此条件下糖蜜酒精废水COD去除率达74.3%.     

活性炭催化过氧化氢氧化脱附其表面吸附的二苯并噻吩

主要研究了活性炭催化过氧化氢氧化脱附其表面吸附的二苯并噻吩。比较了使用H₂O₂水溶液,H₂O₂+HCOOH水溶液和H₂O₂+CH₃COOH水溶液对活性炭进行催化氧化再生的性能,并考察了催化条件对活性炭再生性能的影响。结果表明：3种不同的催化氧化再生方法都能使活性炭获得不同程度的再生,其中,使用H₂O₂+HCOOH水溶液进行催化氧化再生的活性炭再生效果最好,达90％以上。使用H₂O₂+HCOOH水溶液对活性炭进行再生时,H₂O₂浓度、HCOOH浓度、反应温度和时间对活性炭再生性能均有影响,选择合适的催化条件,可使再生性能达到最佳。