流化床垃圾焚烧炉工艺改进的探讨

对流化床垃圾焚烧炉的工艺改进进行了分析 ,在焚烧炉内更有利于脱除酸性气体 ,当垃圾热值达 4 5 0 0kJ/kg时 ,部分吹入氧气可使燃烧温度达 1 30 0℃以上。用空心球代替流动砂可以取消流动砂的循环环节     

基于膨胀特性的厌氧流化床反应器的设计和运行控制

生物流化床的床层膨胀行为直接与生化反应区的水动力学和效率相关 ,床层膨胀特性是进行合理设计和运行的重要依据。目前流化床设计一般没有考虑生物膜的影响 ,但生物颗粒的流化行为有别于光滑载体 ,因此需要对曳力系数Cd 和膨胀特性方程中的ui 进行必要的修正。在综合分析基础上 ,探讨了优化两相流化床设计和运行的程序和方法     

沸腾炉大气污染物初始排放因子的研究

以20台沸腾炉(≤60MW)的燃料特性分析数据和大气污染物的排放实测数据为基础,研究了颗粒物(PM)、SO2和NOX初始排放因子EFP0M、EF0SO2、EF0NOX的变化规律,并利用SPSS13.0统计分析软件,分析了EFP0M、EFS0O2、EF0NOX与影响因子间的相关性。结果表明,在沸腾炉运行负荷≥80%的条件下,EF0PM基本不受锅炉出力(W)、燃煤灰分质量分数(Aar)及过量空气系数(α)的影响,EFP0M与W、Aar、α不具有相关性;EF0SO2主要受燃煤硫质量分数(Sar)的影响,两者具有显著正相关关系;W、α、燃煤干燥基挥发分质量分数(Vdaf)对EF0NOX具有显著影响,EF0NOX与α具有显著正相关关系,而EF0NOX与W、Vdaf具有显著负相关关系;EFS0O2和EF0NOX影响因子由强到弱的顺序为:①EFS0O2:SarαW;②EF0NOX:VdafαW燃煤氮质量分数(Nar)。     

Persistency of highly toxic coplanar PCBs in aquatic ecosystems: uptake and release kinetics of coplanar PCBs in green-lipped mussels (Perna viridis Linnaeus)

The bioaccumulation potential of three highly toxic coplanar PCB isomers [3,3',4,4'-tetrachlorobiphenyl (T(4)CB); 3,3',4,4',5-pentachlorobiphenyl (P(5)CB); and 3,3',4,4',5,5'-hexachlorobiphenyl (H(6)CB)] was investigated using green-lipped mussels (Perna viridis Linnaeus) as a bioindicator, through a transplantation experiment at two locations in Hong Kong waters. By contrast to the relatively rapid uptake and release of many other PCB isomers, the non-ortho chlorine substituted coplanar PCB congeners exhibited slow uptake and clearance. The kinetic parameters of coplanar PCBs based on lipid weight-related data, and the degree of bioaccumulation based on the proportion of coplanar PCBs in total PCBs in mussels, clearly indicate that coplanar PCBs are highly bioaccumulative in lower organisms. On the assumption that mussels are unlikely to be particularly unusual with respect to their bioaccumulation of coplanar PCBs, it appears most likely that these highly toxic and persistent PCB congeners are concentrated by all aquatic organisms, and may reach higher consumers (including humans) in quantities of toxicological concern.     

Comparison of seven indicator PCBs and three coplanar PCBs in beef, pork, and chicken fat

The risk assessment of polychlorinated biphenyls (PCBs) is difficult since complex congeners were used in many industrial applications for a long period of time and the residue monitoring in foods of animal origin and the environment were not established in comparable systems. The relationships of determined concentrations in indicator PCB congeners (mono- and di-ortho PCBs) and coplanar PCB congeners (non-ortho PCBs) in livestock products are presented in this study. The concentrations of seven indicator PCBs were compared with three coplanar PCBs in beef, pork, and chicken fat. Distributions of concentration for the indicator PCBs in three different animal species were similar except for that of PCB-118 (2,3',4,4',5-pentachlorobiphenyl) in pork fat. The congeners with the highest concentration were PCB-138 (2,2',3,4,4',5'-hexachlorobiphenyl) in beef and pork fat and PCB-28 (2,4,4'-trichlorobiphenyl) in chicken fat. The bioaccumulation and metabolism of PCBs in animal species represent different congener profiles in livestock products. The percentage of the total concentration of three coplanar PCBs was about 2% of the total concentration of the seven indicator PCBs. Relatively high concentration of mono-ortho and di-ortho PCBs in fat samples of livestock products may be calculated with the concentration of coplanar PCBs that can be usually determined on a sequential procedure with dioxin analysis. Therefore, the relationship of the amounts between seven indicator PCBs and three coplanar PCBs may be useful to derive the composition and level of contaminants in beef, pork, and chicken.     

TEQ(S) and body burden for PCDDs, PCDFs, and dioxin-like PCBs in human adipose tissue

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), mono-ortho and non-ortho polychlorinated biphenyls (dioxin-like PCBs) were determined in samples of human fat tissue from nine Italian obese patients. The toxicity equivalent (TEQ) values ranged from 9 to 25pgTEQg(-1) lipid (WHO-TEF values, 2005 [Van den Berg, M., Birnbaum, L.S., Denison, M., De Vito, M., Farland, W., Feeley, M., Fiedler, H., Hakansson, H., Hanberg, A., Haws, L., Rose, M., Safe, S., Schrenk, D., Tohyama, C., Tritscher, A., Tuomisto, J., Tysklind, M., Walker, N., Peterson, R.E., 2006. The 2005 World Health Organization reevaluation of human and mammalian Toxic Equivalency Factors for dioxins and dioxin-like compounds. Toxicol. Sci. 93, 223-241]), the contribution of dioxin-like PCBs was more than 30% of the total TEQ values. The obese body burdens varied from 6 to 11ngTEQkg(-1) body weight (BW), exceeding the estimated steady-state body burden 5ngTEQkg(-1) BW, based on lipid adjusted serum concentrations from several populations in the mid-1990s, calculated in the risk assessment US EPA document.     

基于k-Means算法的生活垃圾焚烧设施烟气二恶英防控

为深入探究生活垃圾焚烧设施二恶英的防控方法,采用k-Means算法对华南某生活垃圾焚烧发电厂焚烧设施的运行状态和不同炉内状态下二恶英排放特征及控制机理进行研究。结果表明,该厂3台焚烧炉具有显著不同的运行状态 (类别1和2) (p<0.05) ,在不同状态下,其常规污染物及二恶英排放特征差异显著 (p<0.05) ,类别1炉内状态较差,其排放的CO质量浓度是类别2状态下的2倍,二恶英的质量浓度是类别2状态下的1.5倍。类别1和类别2状态下二恶英的主导生成机理分别为“前驱物合成反应”和“从头合成反应”。为降低二恶英的排放,该厂首先应保证烟气流量大于10.5×10⁴ m³·h⁻¹ (均值11.8×10⁴ m³·h⁻¹) ,其余参数最优范围为：烟气含氧量大于7.0% (均值8.6%) 、CO质量浓度低于9.0 mg·m⁻³ (均值3.5 mg·m^-3) 、烟气湿度小于23.7% (均值21.3%) 、烟气温度为140~154 ℃ (均值145.7 ℃) 。当通过运行控制手段无法保持上述参数控制范围时,应分析原因并考虑停炉检修。本研究结果可为优化焚烧过程、降低二恶英排放、生活垃圾焚烧发电厂长期稳定运行的判别和精细化管理提供参考。     

A comparison of TEQ contributions from PCDDs,PCDFs and dioxin-like PCBs in sewage sludges from Catalonia,Spain

Eight sewage sludges from rural, urban and industrial wastewater treatment plants (WWTPs) in Catalonia (Spain) were analysed for polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) to determine the present levels of contamination. A method based on an automated cleanup system followed by an isotope-dilution high-resolution mass spectrometric analysis was employed. Total toxicity equivalent (WHO-TEQ) values were calculated using the toxicity equivalent factors (WHO-TEFs) proposed by WHO for dioxin-like PCBs, PCDDs and PCDFs. The WHO-TEQ(PCDD/F) values for these samples ranged from 4.9 to 20.8 pg/g dry weight (d.w.), with a mean value of 9.3 pg/g d.w., whereas WHO-TEQ(PCB) levels ranged between 1.9 and 6.6 pg/g d.w., with a mean value of 4.2 pg/g d.w. The WHO-TEQ(PCB) contribution varied from 13% to 50%, suggesting that PCB contribution on the toxicity of the samples must be taken into account. Moreover, these contemporary PCDD, PCDF and PCB concentrations were compared with previous data obtained from sewage sludge samples collected during the 80s. Our findings show that contemporary PCDD, PCDF and PCB levels have declined since the 80s.     

油田油泥与煤在流化床中的混烧

基于小型流化床焚烧实验平台,通过含油污泥与煤混合燃烧,分析气体污染物排放浓度以及灰渣特性。含油污泥与煤混烧后NOx、SO2的排放浓度均低于危险废物焚烧排放标准。根据灰渣中组分分析,煤中碱金属化合物能抑制SO2的排放。渣样的浸出毒性均在标准范围内,灰样的浸出毒性高于渣样,主要因为飞灰中更容易富集挥发和易溶形态的重金属。基于小试实验的结果,油泥在小型流化床上的燃烧不充分导致了CO排放浓度较高,且灰的灼减率较高,因此,在后续中试以及示范工程中,应保证油泥的充分燃烧,为灰渣的综合利用提供理论基础。     

厌氧流化床处理白酒废水运行参数的研究

研究了床层膨胀率、HRT、温度以及有机容积负荷冲击等因素对AFB反应器COD去除率的影响。结果显示:温度为32±2℃,进水COD 6 000 mg/L,pH7.2条件下,AFB反应器处理白酒废水的优化运行参数为床层膨胀率为36%,回流比1∶7,水力停留时间8 h,此时废水COD去除率可达80%左右;同时该反应器在有机容积负荷达到36.1 kg COD/(m3.d)时COD去除率明显下降。     

Characterisation and fingerprinting of PCBs in flue gas and ash from waste incineration and in technical mixtures

Congener patterns of mono- to deca-chlorinated biphenyls (PC1-10B) were evaluated in (a) waste incineration flue gases collected in the post-combustion zone of a laboratory-scale fluidized-bed reactor, (b) ashes from two different MSW incineration plants, and (c) published data of eight Aroclor formulations. The congener patterns of the flue gases, ashes, and Aroclor mixtures clearly differed from each other, likely reflecting differences in formation pathways. The flue gas congener patterns were largely dominated by the least chlorinated congeners, whereas the ashes displayed more evenly distributed patterns. The most abundant congeners indicated a preference for 3,3',4,4'-oriented substitution, which may be related to de novo-type formation involving perylene. Principal component analysis confirmed that congener patterns differed among the three matrices and also distinguished flue gases collected at 200 °C from those collected at 300 °C and 450 °C. This distinction could be partly explained by the degree of chlorination, although the substitution status of the ortho-position, and substitution in the 3,3',4,4'-positions also seemed to be influential. Injecting biphenyl into the post-combustion zone of the reactor did not alter the patterns, indicating that availability of the backbone structure is not a limiting factor for PCB formation.     

SBR式流化床船用生活污水处理设备及其处理效果

介绍了SBR式流化床船用生活污水处理设备的组成结构，对该设备进行了启动试验和污水处理效果试验，结果表明该设备具有启动方便、反应时间短的特点。当处理周期为2h时，处理设备的出水水质完全满足《船用生活污水处理系统技术条件》（GB10833-89）的要求。     

SBR式流化床船用生活污水处理设备及其处理效果

介绍了SBR式流化床船用生活污水处理设备的组成结构,对该设备进行了启动试验和污水处理效果试验,结果表明该设备具有启动方便、反应时间短的特点.当处理周期为2 h时,处理设备的出水水质完全满足<船用生活污水处理系统技术条件>(GB10833-89)的要求.     

厌氧流化床微生物燃料电池及其串并联性能

在高650 mm、有效容积1 280 mL的液固厌氧流化床单室无膜空气阴极微生物燃料电池（MFC）中,研究了燃料电池串并联产电和有机污水处理性能,同时考察了电极面积、活性炭装填体积、温度等因素对产电性能的影响。结果表明,将燃料电池串联,总电压等于3个单级电池的电压之和,约为2 100 mV,最大功率为0.12 mW,而单级电池最大功率为0.05 mW。并联时,输出电压为800 mV,和单级电池输出电压大体相当,而电流为单级电流的2倍。阳极面积增加1倍,产电量增大了30%;电压随活性炭装填体积的增大而增大;温度为40℃时,燃料电池的产电性能最好。     

Global pollution monitoring of polychlorinated dibenzo-p-dioxins (PCDDs), furans (PCDFs) and coplanar polychlorinated biphenyls (coplanar PCBs) using skipjack tuna as bioindicator

In order to elucidate the global distribution of dioxins and related compounds, such as PCDDs, PCDFs and coplanar PCBs, levels of these compounds were determined in the muscle of skipjack tuna (Katsuwonus pelamis) collected from the offshore waters and open seas near Japan, Taiwan, Philippines, Indonesia, Seychelles and Brazil, and the Japan Sea, the East China Sea, the South China Sea, the Indian Ocean and the North Pacific Ocean. PCDDs, PCDFs and coplanar PCBs were detected in almost all the specimens collected from all the locations surveyed, indicating widespread contamination by these compounds in the marine environment. Higher concentrations of dioxins and coplanar PCBs were detected in the samples from temperate Asian regions, plausibly due to larger usage and anthropogenic generation in highly industrialized countries around the East China Sea and the South China Sea, such as Japan, Korea, Taiwan, Hong Kong and coastal China.     

Levels of PBDEs, PCDDs, PCDFs, and coplanar PCBs in edible fish from California coastal waters

The levels of polychlorinated dibenzo-dioxins (PCDDs), polychlorinated dibenzo-furans (PCDFs), coplanar polychlorinated biphenyls (coPCBs), and polybrominated diphenyl ethers (PBDEs) were measured in fish collected from San Francisco Bay in 2000 and from the California coast in 2001. The samples were composites of only the edible portions of the fish (skin on, skin off, or whole body minus head and guts) of comparable size and from distinct geographical areas. Sixty-five composite samples were analyzed for PCDD/PCDF/coPCBs, and 43 composite samples were analyzed for PBDEs. For all fish of all species from all sampling areas, the mean concentration of the sum of BDEs 47, 99, 100, 153, and 154 was 302 ng/g lipid weight, with BDE 47>100>99 approximately 154>153. For all fish of all species from all sampling areas, the mean PCDD/PCDF International Toxic Equivalent (I-TEQ) was 33.1 pg/g lipid. For the three coPCBs (77, 126, 169), the mean I-TEQ for all fish of all species from all sampling areas was 109 pg/g lipid. The highest concentrations of both PCDD/PCDF/coPCBs and PBDEs were found in the highly populated areas of San Francisco Bay, the Los Angeles area, and San Diego Bay.     

Evaluation of mitogen-induced responses in marine mammal and human lymphocytes by in-vitro exposure of butyltins and non-ortho coplanar PCBs

The effects of exposure to butyltin compounds (BTs: tributyltin; TBT, dibutyltin; DBT and monobutyltin; MBT) and non-ortho coplanar PCBs (IUPAC 77, 126 and 169) on marine mammals and human lymphocyte were evaluated. Peripheral blood mononuclear cells (PBMCs) isolated from Dall's porpoises (Phocoenoides dalli), bottlenose dolphins (Tursiops truncatus), a California sealion (Zalophus californianus), a larga seal (Phocoa largha) and humans (Homo sapiens) were exposed at varying concentrations of BTs and coplanar PCBs. Concanavalin A (Con A)-stimulated mitogenesis found significantly suppressed (P<0.01) when the cells were exposed at 300 nM (89 ng/ml) of TBT and 330 nM of DBT (77 ng/ml), while MBT showed little cytotoxicity at treatment levels of up to 3,600 nM (620 ng/ml). BTs concentrations in the liver of Dall's porpoises from Japanese coastal waters ranged between 81-450 ng/g for TBT and 200-1,100 ng/g (wet wt.) for DBTs, which is greater than the cytotoxic levels registered in this study. In contrast, non-ortho coplanar PCBs did not suppress cell proliferation at concentrations of up to 30 nM (10 ng/ml). The residue levels of coplanar PCBs in the blubber of Dall's porpoises were 0.12-1.3 ng/g, which were one order of lower than those levels that do cell proliferation. When cells were exposed to a mixture of TBT/DBTand coplanar PCBs, the proliferation was significantly reduced to 33 nM DBT plus 34 nM CB-77 and 33 nM DBT plus 28 nM CB-169 mixtures, respectively. The investigations relating the contaminant-induced immunosuppression in marine mammals have been focused on persistent organochlorines such as PCBs. pesticides and dioxin compounds. However, this study suggested the possibility of BTs could also pose a serious threat to the immune functions in free-ranging marine mammals and humans.     

Leaching characteristics of PCDDs/DFs and dioxin-like PCBs from landfills containing municipal solid waste and incineration residues

To investigate the leaching characteristic of persistent organic pollutants (POPs), such as non-ortho and mono-ortho substituted chlorobiphebyls (dioxin-like PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs), in leachate from municipal solid waste (MSW) landfill sites containing incineration residues, raw leachate samples were collected twice from 12 selected MSW landfill sites. The samples were divided into their liquid and solid phases using GF/B (pore size 1.0 microm), and the concentrations of POPs then determined. The concentrations of PCDDs/DFs ranged from 0.65 to 5.88 pg-TEQ/l (average 2.86 pg-TEQ/l), and those of dioxin-like PCBs from 0.05 to 0.32 pg-TEQ/l (average 0.18 pg-TEQ/l). The major congeners of leached PCDDs/DFs and dioxin-like PCBs in liquid and solid phases were OCDD (about 60%), 2,3',4,4',5-PeCBs (about 30%), and 2,3,4,4',5-PeCBs (about 54%). The relationship between landfill age and the leaching concentration of PCDDs/DFs, and effects of dissolved organic carbon (DOC) on the leaching of PCDDs/DFs are also discussed. Finally, a leaching prediction model of PCDDs/DFs from MSW landfills has been suggested using parameters, such as hydrophobic neutral organic carbons, total dissolved solid, and the ratio of non-biodegradable wastes in landfill sites.