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1.
A hybrid selective noncatalytic reduction/selective catalytic reduction (SNCR/SCR) system that uses two types of technology, low-temperature SCR process and SNCR process, was designed to develop nitrogen oxide (NOx) reduction technology. SCR was conducted with space velocity (SV) = 2400 hr?1 and hybrid SNCR/SCR with SV = 6000 hr?1, since the study focused on reducing the amount of catalyst and both achieved 98% NOx reduction efficiency. Characteristics of NOx reduction by NH3 were studied for low-temperature SCR system at 150 °C using Mn-V2O5/TiO2 catalyst. Mn-added V2O5/TiO2 catalyst was produced, and selective catalyst reduction of NOx by NH3 was experimented. NOx reduction rate according to added Mn content in Mn-V2O5/TiO2 catalyst was studied with varying conditions of reaction temperature, normalized stoichiometric ratio (NSR), SV, and O2 concentration. In the catalyst experiment according to V2O5 concentration, 1 wt.% V2O5 catalyst showed the highest NOx reduction rate: 98% reduction at temperature window of 200~250 °C. As a promoter of the V2O5 catalyst, 5 wt.% Mn was added, and the catalyst showed 47~90% higher efficiency even with low temperatures, 100~200 °C. Mn-V2O5/TiO2 catalyst, prepared by adding 5 wt.% Mn in V2O5/TiO2 catalyst, showed increments of catalyst activation at 150 °C as well as NOx reduction. Mn-V2O5/TiO2 catalyst showed 8% higher rate for NOx reduction compared with V2O5/TiO2 catalyst in 150 °C SCR. Thus, (5 wt.%)Mn-(1 wt.%)V2O5/TiO2 catalyst was applied in SCR of hybrid SNCR/SCR system of low temperature at 150 °C. Low-temperature SCR hybrid SNCR/SCR (150 °C) system and hybrid SNCR/SCR (350 °C) showed 91~95% total reduction rate with conditions of SV = 2400~6000 hr?1 SCR and 850~1050 °C SNCR, NSR = 1.5~2.0, and 5% O2. Hybrid SNCR/SCR (150 °C) system proved to be more effective than the hybrid SNCR/SCR (350 °C) system at low temperature.

Implications:?NOx control is very important, since they are the part of greenhouse gases as well as the cause of acid rain and ozone hole. A technology, so-called hybrid SNCR/SCR process, was tested using Mn-V2O5/TiO2 monolithic catalyst for NOx reduction, and the method is promising. The results of this study would provide some ideas to parties such as policy makers, environmental engineers, and so on.  相似文献   

2.
为高效回收抗生素菌渣中的蛋白质,采用不同沉淀法分离青霉素菌渣中的蛋白质。首先,考察不同沉淀法对蛋白质的沉淀效果,选出最优蛋白质沉淀方法;然后,开展单因素实验并基于响应曲面法选择分离青霉素菌渣中蛋白质的最优工艺参数;最后,利用最优工艺条件对青霉素菌渣进行蛋白质分离实验验证。结果表明,三氯乙酸(TCA)沉淀法沉淀效果最好,其分离青霉素菌渣中蛋白质的最优工艺条件为:TCA的质量分数为20%、水解液pH为3.0、沉淀时间为10 h和离心转速为10 000 r·min−1;此条件下的预测蛋白质沉淀率为89.5%,实际蛋白质沉淀率为89%。该研究结果可为菌渣蛋白质高效回收提供参考。  相似文献   

3.
菇渣的厌氧发酵特性   总被引:1,自引:0,他引:1  
为提高菇渣的利用效率,以菇渣为发酵原料,在35 ℃下,进行初始干物质浓度为6%、8%、10%和12%的厌氧发酵,考察了初始干物质浓度对产甲烷性能及有机质降解的影响。结果表明:初始干物质浓度在10%时发酵效果最佳,此时累计产甲烷量、VS产气率和VS产甲烷率分别为4 034.71 mL、235.15 mL·g -1和134 mL·g -1,VS降解率为43.19%;菇渣的沼气产率与VS降解率成正比;淀粉、脂肪和蛋白质的降解率分别为99.01%、70.78%和17.16%;总纤维素的降解率为30.37%,以半纤维素降解为主。实验结果说明,菇渣具有较高的产气性能;产生的沼气主要来源于微生物对碳水化合物的降解。  相似文献   

4.
通过选取涵盖技术性能、经济效益、环境影响和社会影响4个方面的评估指标体系,建立了关于抗生素制药菌渣的处理处置技术评估层次分析-模糊数学综合筛选模型,其中,层次分析法用于确定一级指标、二级指标的权重,专家打分法与定量法相结合构成了模糊数学综合评估模型。采用评估模型对堆肥、厌氧消化、水煤浆、制备酵母膏/粉代用品、吸附材料、焚烧及填埋7种技术进行了综合评估。结果显示,社会影响和环境影响两项指标权重较大,均为0.338 9,经济效益权重为0.153 5,技术性能权重为0.068 7。堆肥技术为Ⅳ级,厌氧消化、制备酵母膏/粉代用品、水煤浆、吸附材料等技术为Ⅲ级,焚烧技术为Ⅱ级,填埋技术为Ⅰ级。最后,结合各种技术的一级指标和二级指标的得分结果,对各种技术存在的具体问题进行了分析。  相似文献   

5.
Characteristics of leachate from pyrolysis residue of sewage sludge   总被引:3,自引:0,他引:3  
Hwang IH  Ouchi Y  Matsuto T 《Chemosphere》2007,68(10):1913-1919
The pyrolysis residue (SP) of sewage sludge (SS) produced at 500 degrees C was subjected to batch and column leaching tests to investigate the release of its organic and inorganic constituents and metals. For comparison, incineration ash (SI) obtained from a SS incinerator was also tested. Pyrolysis and incineration reduced organic matter of SS from 0.78 kg kg(-1)-dry SS to 0.16 and 0.01 kg kg(-1)-dry SS, respectively. Heavy metals remained in SP without being volatilized, although Cd and Pb were transferred into the off-gas during incineration. In the batch leaching test with the leaching liquid-to-solid mass ratio (L/S)=10, the pH of the SS, SP, and SI filtrates was 6.3, 7.9, and 11.0, respectively. The total organic carbon concentrations were in the order SS (877 l mg l(-1))>SP (99 mg l(-1))>SI (26 mg l(-1)). The SP and SI filtrates met the landfill standard for the Cd and Pb concentrations (<0.3 mg l(-1)). In the column tests, although the SP contained more organic matter than that of SI, its carbon discharge into the leachate under aerobic conditions was similar to that of SI under anaerobic conditions. The leaching of heavy metals, such as Cd, Cr, Pb, and Zn, was also suppressed in SP during the active decomposition of organic matter. We demonstrated that pyrolysis reduces the potential release of pollutants from sewage sludge in landfill, making it a promising method of treating sewage sludge before landfilling.  相似文献   

6.
从矿山废水中经富集分离到一株能以黄原酸盐为惟一碳源的黄原酸盐降解菌,初步鉴定为铜绿假单胞菌属.菌株降解黄原酸盐的最佳条件为:pH为8,温度30℃,振荡速率120 r/min.当黄原酸盐浓度达到1500 mg/L时,24 h后浓度降解率为95.7%,COD去除率为84.7%.黄原酸盐浓度越高,COD去除率越高.当加入0.2 g/L的葡萄糖时可大大提高菌对黄原酸盐的降解率.  相似文献   

7.
一株有机浮选药剂——黄原酸盐降解菌的特性研究   总被引:10,自引:0,他引:10  
从矿山废水中经富集分离到一株能以黄原酸盐为惟一碳源的黄原酸盐降解菌,初步鉴定为铜绿假单胞菌属。菌株降解黄原酸盐的最佳条件为:pH为8,温度30℃,振荡速率120r/min。当黄原酸盐浓度达到1500mg/L时,24h后浓度降解率为95.7%,COD去除率为84.7%。黄原酸盐浓度越高,COD去除率越高。当加入0.2g/L的葡萄糖时可大大提高菌对黄原酸盐的降解率。  相似文献   

8.
细菌浸出电解锰废渣中锰的机制研究   总被引:1,自引:0,他引:1  
从电解锰废渣中分离出一株高效浸锰菌,经鉴定为沙雷氏菌(Serratia sp.).考察了电解锰废渣培养液、MnO2培养液在有菌和无菌条件下的锰浸出情况,以及有菌液和无菌液在加入不同还原剂后的锰浸出情况.结果表明,在初始pH为6.0、固液质量比为1:10、温度为37 ℃的浸出条件下,在电解锰废渣培养液中,无菌条件下的锰浸出率远小于有菌条件下的,反应72 h后,无菌、有菌条件下的锰浸出率分别为8.030 00%、78.670 00%;无论在有菌还是无菌条件下,MnO2培养液中的锰浸出率都较低,反应72 h后,无菌、有菌条件下的锰浸出率分别为0.000 39%、0.041 00%;有菌液加入ZnS、FeS、FeSO4、Fe2(SO4)3、CuS还原剂后,反应72 h的锰浸出率分别为73.340 00%、70.980 00%、69.680 00%、10.260 00%、1.670 00%;无菌液中加入4种还原剂(不包括CuS)后的锰浸出率都相当低, 反应72 h后,锰浸出率相对较高的是FeS和ZnS,均为0.006 20%,锰浸出率相对最低的是Fe2(SO4)3,为0.005 00%;沙雷氏菌对电解锰废渣中锰的浸出既不是直接氧化浸出作用,也可能不是间接产酸浸出作用,而可能是一种催化还原作用.  相似文献   

9.
针对抗生素菌渣中抗生素残留难处理的问题,采用好氧堆肥法将其制成有机肥料,以实现其无害化处理及资源化利用。通过将复合菌剂添加到好氧堆肥体系中,研究其对堆体理化性质、肥效、毒性和微生物群落的影响。结果表明,添加复合菌剂最高温度可达70.55 ℃,比对照组高温期延长了5 d,减少了氮源流失,有机质降解率提高了5.56%,土霉素降解率高达98.86%,使堆肥产品达到安全水平。此外,复合菌剂提高了堆肥中放线菌门(Actinobacteria)和厚壁菌门(Firmicutes)的相对丰度,与堆体升温正相关的嗜热菌属(Thermophilic bacteria genera)丰度显著增加(P<0.01),而致病细菌相对丰度下降。细菌群落相关性分析结果表明,接种菌剂既增加了微生物活性,降低了细菌群落的复杂度,又为优化建立新的和更加健康的堆肥细菌群落奠定了基础。本研究可为抗生素降解菌渣在堆肥中的应用提供参考。  相似文献   

10.
尹朗  赵丹  张素佳  王海波 《环境工程学报》2016,10(10):5453-5458
通过454高通量测序对北方A和B两实际饮用水管网系统中生物膜细菌群落特征进行表征,并研究了其对管网腐蚀产物组成的影响。结果表明,A管网生物膜细菌群落丰度和多样性高于B管网生物膜。在门水平上,两管网生物膜细菌群落主要为变形菌门Proteobacteria,但B管网生物膜中的相对丰度(67.10%)高于A(46.50%)。在纲水平上,A管网生物膜主要为β-变形菌纲Betaproteobacteria,B管网生物膜中主要为β-变形菌纲Betaproteobacteria和δ-变形菌纲Deltaproteobacteria。在属水平上,A管网生物膜中腐蚀相关菌群主要为硝酸盐还原菌和铁还原菌,其腐蚀产物主要为α-FeOOH和Fe3O4,而B管网生物膜中硫酸盐还原菌特别是脱硫弧菌属Desulfovibrio含量较高,其可能与管垢中绿锈含量高有关。  相似文献   

11.
在自行设计制备的真空热解炉中进行了废印制线路板的热解实验,得到固体、液体和气体产物。着重研究了热解固体渣中金属铜和非金属玻璃纤维的物理分选、热解固体渣分析及有氧煅烧对玻璃纤维纯度的影响。结果表明,物理分选效率很高,金属铜的回收率和纯度接近100%;热解固体渣含30.35%的铜、56.21%的玻璃纤维和13.45%的炭黑;有氧煅烧去除炭黑可得到高纯度的玻璃纤维。  相似文献   

12.
京杭运河杭州段水体污染和细菌群落结构特征   总被引:1,自引:0,他引:1  
为了解人类活动对城市河道水体污染和细菌群落的影响,选取京杭运河杭州段进行了分季节采样研究。测定了水体的环境与水质参数,分析了细菌丰度、胞外酶活性和群落结构变化。结果显示,从上游到下游,水体中高锰酸盐指数、氨氮、总氮以及细菌丰度和β-葡萄糖苷酶活性大体呈递增趋势,冬季水体总体污染水平及细菌丰度均显著高于其他季节。水体中细菌的主要种类集中在变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、拟杆菌门(Bacterioidetes)、厚壁菌门(Firmicutes)和蓝藻门(Cyanobacteria),所占比例分别为37.8%、24.3%、18.9%、10.8%和8.1%,属于黄杆菌(Flavobacterium)、厚壁菌(Firmicutes bacterium)和放线菌(Actinobacterium)的细菌是水体中大多数时间的优势细菌。限制性排序分析显示,水体细菌群落结构从上游到下游差异明显,高锰酸盐指数和总氮是关键影响因子。杭州市区由人类活动产生的污染物输入是京杭运河杭州段的主要污染源,水体细菌群落对水体污染物的变化有着明显的响应。  相似文献   

13.
为探究农村小管径重力流灰水管道系统生物膜的细菌群落结构特征,建立了一套模拟真实农村环境条件下水量变化且具有3组坡度参数(5‰,10‰,15‰)的小管径灰水管道实验设备,利用Illumina HiSeq高通量测序技术,分析了连续运行60 d后的管道生物膜的细菌群落特征。结果表明:ProteobacteriaActinobacteriaBacteroidetes为优势菌门,优势菌属为PaenarthrobacteEnsiferSpingopyxis,坡度变化会显著影响生物膜细菌群落组成;小管径重力流灰水管道生物膜中存在一定丰度的反硝化细菌和硝化细菌,具有生物脱氮功能。通过PICRUSt功能预测发现,高坡度(15‰)的灰水管道具有更高的硝化和反硝化基因丰度。进一步分析可知,小管径灰水管道采用高敷设坡度的设计方案可能具有更强的生物脱氮能力。  相似文献   

14.
Environmental Science and Pollution Research - A large amount of kitchen waste is produced all over the world. Biochemical disposal is an effective method for the reduction and safe utilization of...  相似文献   

15.
Aim of the present study was an attempt to find a correlation between physicochemical structure of veterinary drugs and the maximum residue limit (MRL) for muscle tissue of food producing animals. Direct correlation and analysis in quintile groups for 52 physicochemical parameters were performed. An internal validation using leave-one-out cross-validation was performed. In the quintile groups, there were 11 arithmetic expressions created for the limited group of individual parameters (13 from 52 analyzed), which showed a significant linear or quadratic correlation between the number of quintile group and the mean value of MRL within the quintile. The results obtained suggest that there is no direct correlation between individual physicochemical parameters and MRL value in muscle tissue; however, such correlation can be determined for arithmetic expressions created on the basis of several physicochemical parameters, using quintile group analysis.  相似文献   

16.
典型铬渣简易掩埋场铬渣及土壤铬污染特征和处置分析   总被引:6,自引:1,他引:6  
通过钻孔采样分析,研究了典型铬渣简易掩埋场地下铬渣及土壤铬中Cr6 、总Cr的分布特征和污染状况,结果表明,铬渣简易掩埋场铬污染程度严重,引起了周边和地下深部较大面积的土壤污染,深度达到了地下的基岩.铬含量在土壤层剖面中分布呈现规律性变化,即随土壤深度增加,Cr6 、总Cr含量逐渐下降,但绝大多数超过了危险废物毒性鉴别标准.从铬污染程度上看,总体上存在铬渣>土壤>人工填土.在此基础上,提出了铬渣及污染土壤的处置方式,为铬渣污染治理和资源化利用提供科学依据.  相似文献   

17.
利用氨碱法生产纯碱产生的废弃物——碱渣为主要原料制备免烧砖,研究了碱渣、粉煤灰、钢渣和石粉等不同含量对免烧砖强度的影响,优化了配比。研究表明:碱渣、粉煤灰、钢渣、石粉质量配比为4:3:2:1时,免烧砖的7 d和28 d的抗压强度分别达到了14.0 MPa和20.6 MPa,吸水率为13.4%;扫描电镜表征结果,免烧砖内部颗粒分布均匀,界面结合良好;X-射线衍射表征其主要矿相为CaCO3、Ca2SiO3Cl2、Ca3Si6O12(OH)6·5H2O。实验结果表明,免烧砖能有效利用碱渣,工艺简单,成本低。  相似文献   

18.
Dynamics of fipronil residue in vegetable-field ecosystem   总被引:4,自引:0,他引:4  
Zhou P  Lu Y  Liu B  Gan JJ 《Chemosphere》2004,57(11):1691-1696
Fipronil insecticide has been widely used to control vegetable pests in China recently. The research was conducted to evaluate the fate of fipronil in vegetable-field ecosystem and provide the scientific basis of using this insecticide. Developed on the analytical methods of fipronil residue and its four metabolisms, the degradation dynamics of their residue in a vegetable and the soil of the vegetable fields was studied. The results showed that (1) degradation of fipronil was faster in pakchoi (half-life 2.6 days) than in soil (half-life 7.3 days); (2) degradation reaction occurred in soil was governed mainly by photodegradation and oxidization accompanying with production of the metabolites, MB46513 and MB46136. Reduction and hydrolyzation played little role in the degradation process. In pakchoi, degradation was mainly contributed by reduction though oxidization and hydrolyzation occurred simultaneously. The metabolite products were MB45950, MB46136 and RPA200766; (3) the final residue in pakchoi was at a level of 0.003 mg kg−1, which was much lower than the USA’s upper limit of 0.04 mg kg−1 in rice. Therefore, a dosage of 24 g hm−2 was suggested and considered as safe to human beings and animals.  相似文献   

19.
氰化渣资源化优选模型的研究   总被引:1,自引:0,他引:1  
依据层次分析法原理,从经济、环境和资源化3个影响因素建立氰化渣资源化途径优选的递阶层次结构模型。以山东某黄金开发公司氰化法提炼黄金产生的氰化渣为研究案例,从氰化渣组成成分与含量分析的角度出发,结合氰化渣各资源化途径的独特要求,探讨氰化渣资源化特性与资源化途径的密切关系,拟合出氰化渣的各种资源化特性,作为结构模型中的资源化因子。然后分别对模型中的3个影响因素进行定性和半定量化处理,最终实现氰化渣资源化途径优选的决策评价,为政府部门和环境管理者提供决策参考。  相似文献   

20.
两段式热解厨余垃圾实验研究   总被引:5,自引:2,他引:3  
通过厨余垃圾的工业分析,发现其挥发分比例较高,适合热解利用;采用热重分析方法分析了不同条件下厨余垃圾的热解特性,提出了厨余垃圾两段式热解转化利用的思路,得出了厨余垃圾热解的合适工艺条件。在自行设计建造的一段回转炉、二段焦化罐中对厨余垃圾热解,并分析了产物的组成和性质。  相似文献   

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