污泥与煤和煤矸石共燃特性研究

利用STA 409 PC型同步热分析仪,对煤、煤矸石和污泥不同质量比样品的燃烧过程进行了热重分析。结果表明,单一煤和煤矸石的DTG曲线都只有一个明显的失重峰,污泥的DTG曲线有两个明显的失重峰,而混合物的DTG曲线都有两个失重峰。通过分析不同样品的混燃过程,发现随着煤所占质量比的增加,最大失重峰速率所对应的温度都有所降低。煤、煤矸石、污泥及其混合物的活化能为16.93kJ/mol～109.89kJ/mol。随着污泥所占质量比的增加,混合物的着火温度有所降低,当达到70%时,污泥与煤混合物的着火点接近单一污泥的着火点。     

磷对泥/煤混燃灰熔融特性的影响及矿物相演变规律

采用灰熔点仪、X射线荧光仪(XRF)研究了无机非金属P2O5对城市污水污泥与烟煤的混烧灰熔融特性的影响,利用X射线衍射仪(XRD)、X射线光电子能谱仪(XPS)研究在各混烧温度下灰中含磷矿物在晶体和非晶体间的演变。结果表明,对于Al_2O_3含量较多且熔点较高的灰样,磷含量的增加可显著降低其灰熔点,P2O5含量在0-4%时影响最大,使其灰熔点降低126℃;但对碱性含量高的灰样的影响较小。低温灰中主要以磷酸铝(AlPO_4)晶体为主,温度升高后,与硬石膏(CaSO_4)等含钙矿物和赤铁矿(Fe_2O_3)反应生成晶体Ca_3(PO_4)_2和玻璃相(Fe_2O_3)_(0.252)(P_2O_5)_(0.748),磷含量增加可使灰中玻璃相(Fe_2O_3)_(0.252)(P_2O_5)_(0.748)增加,是磷降低灰熔点的主要原因。     

Simultaneous determination of fluoroquinolone and tetracycline antibacterials in sewage sludge using ultrasonic-assisted extraction and HPLC-MS/MS

A reliable method was proposed for the simultaneous determination of five fluoroquinolones (FQs) and two tetracyclines (TCs) in sewage sludge using ultrasonic-assisted extraction (USE) followed by SPE cleanup and high-performance liquid chromatography-mass spectrometry (HPLC-MS)/MS analysis with electrospray ionisation (ESI) in a positive mode. The USE conditions (e.g. extraction solvent, pH, and extraction cycles) and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) parameters were optimised. Quantification was performed by internal standard calibration in multiple reaction monitoring mode. Recoveries of the antibacterials ranged from 41 to 123%, with relative standard deviations within 17%. The sample-based limits of quantification were 10–63?ng?g^?1 dry weight (dw) for FQs (ciprofloxacin, enrofloxacin, lomefloxacin, norfloxacin, and ofloxacin) and 250–500?ng?g^?1 dw for TCs (tetracycline and oxytetracycline). The method was applied to determine the antibacterials in sewage sludge and sediment samples were collected from the Pearl River Delta, China. Ciprofloxacin, norfloxacin, and ofloxacin were frequently detected, ranging from 1052 to 17740?ng?g^?1 dw in dewatered sludge samples, 585–3545?ng?g^?1 dw in untreated solids, and 98–258?ng?g^?1 dw in an urban stream sediment sample, respectively. Lomefloxacin and enrofloxacin were also occasionally detected.     

酸洗污泥与煤共燃烧过程中重金属的迁移分布研究

采用高温管式炉系统进行酸洗污泥与煤共燃烧实验。对共燃烧后As、Cr、Ni、Cd、Cu、Mn、Pb、Zn、Sb、Se重金属元素在烟气、飞灰及炉渣中的分配率进行分析。结果表明,Cd、Se、Zn是易挥发重金属,主要分布在烟气和飞灰中。Cd在烟气中的最大分配率为61%;Se在烟气中的分配率为38.58%~94.612%;Zn在低、高温段分别主要分布在烟气和飞灰中。As、Cu、Pb、Sb是半挥发重金属,Pb在炉渣中的分配率较稳定,分配率为42.67%~64.76%,在烟气和飞灰中的分配率波动较大,其分配率分别是14.176%~45.79%和9.78%~32.55%;Sb在烟气中的最大分配率为37.64%;温度升高反而会抑制As、Cu挥发,这与高温下As、Cu易与矿物质反应生成络合物有关。Ni、Cr、Mn属于难挥发重金属,绝大部分残留在炉渣中,且分配率对温度变化不敏感。赋存于炉渣中的Cr、Ni分别超过95%和97%;随着温度升高,Mn在炉渣中的分配率由71.46%增加到96.89%。     

长江三角洲地区污水厂污泥中全氟有机酸污染特征

对长江三角洲地区污泥的分析结果表明：脱水剩余污泥中总全氟有机酸（PFAs）的浓度范围为122-1098ng／g,其中三氟乙酸（TFA）和五氟丙酸（PFPrA,除S13未检出外）一般是污染水平最高的两种PFAs,分别为107-562ng／g和4．41-395ng／g,占总PFAs的12％-93％和0．7％-61％,这充分说明在以后的监测中需要将超短链PFAs纳入检测范围．尽管全氟辛酸（PFOA）和全氟辛磺酸（PFOS）的浓度一般低于超短链的TFA和PFPrA,甚至在某些情况下还会低于部分中长链PFCAs,但在绝大多数情况下它们依然是两种主要的PPAs类污染物,浓度分别为2．78-66．9ng／g和1．27-80．4ng／g,占总PFAs的0．7％-8．8％和1％-20％．一般而言,全氟羧酸（PFCAs）的检出率较高,可达92．3％-100％,但是对全氟烷基磺酸（PFSAs）而言,除PFOS的检出率为100％外,全氟丁磺酸（eFBS）和全氟己磺酸（PFHxS）的检出率较低,仅分别为15．4％和7．8％．此外,不同的污水处理工艺可能会严重影响污水处理过程中PFAs污染水平和归趋,造成这种现象的原因可能是不同工艺条件下污泥的吸附性能不同,也可能是不同处理工艺对其前体物的降解转换率不同．     

Comparison of three digestion methods for the determination of the aqua regia soluble content of lead,cadmium and chromium in sewage sludges by ETAAS

A procedure for the determination of the aqua regia soluble content of lead, cadmium and chromium in a sewage sludge reference material (CRM 145R) by electrothermal atomic absorption spectrometry (ETAAS) is described. A comparison of the dissolution procedure proposed in the certification report, to an oven-assisted digestion and a proposed microwave digestion procedure is performed. In the ETAAS method developed, 1 g of Pt proved to be an appropriate modifier for each of the above heavy metals. Possible sources of error at each analytical step are addressed. The metal contents obtained with the proposed method are in a good agreement at 95% significance level with the certified values given for CRM 145R.     

钾对秸秆混煤燃烧特性影响的研究

选用经酸洗法脱灰的煤和秸秆制得实验样品。采用TG/DTG/DTA技术研究了不同秸秆含量下碱金属钾对秸秆与煤混合燃烧特性的影响。研究结果表明,KOH促进脱灰煤和脱灰混合样品的着火燃烧,使其最大燃烧速率温度及燃尽温度降低,但提高了脱灰秸秆的着火温度。秸秆混煤燃烧反应符合一级反应模型,KOH的添加对混煤燃烧具有催化作用,使混合燃烧反应活化能降低10kJ/mol。     

煤与生物质混烧灰荷电特性研究

对玉米秸分别与两种煤以不同比例混烧生成的混烧灰进行了荷电特性研究。利用法拉第杯荷电量检测系统和静电低压撞击器(ELPI)测量了混烧灰的总体荷质比及分级荷质比,并借助于成分分析及形貌分析结果讨论了其影响机理。结果表明,随着生物质掺入量在混烧燃料中的增加,混烧灰的成分组成发生变化,使得其介电常数变大,比电阻增大,表面吸附能力增强,从而使混烧灰的总体荷质比有一定的上升趋势。对混烧灰的分级荷质比测量结果表明,排除灰样粒径的影响,生物质的掺入使得混烧灰的荷电能力得以增强,但影响相对较小,颗粒粒径是影响混烧灰荷电能力的主要因素。     

水热污泥与煤在混燃过程中的协同效应特性研究

以城市污泥衍生的水热污泥(SS-derived hydrochar)为对象,结合傅里叶红外光谱分析(FT-IR)、X射线荧光光谱分析(XRF)和X射线衍射分析(XRD)等对比研究了水热污泥与三种不同品阶煤(褐煤、烟煤和无烟煤)在有机/无机结构与燃料特性上的异同;同时,通过热重(TG)与偏差分析(Deviation)考察水热污泥与各阶煤在不同混合比例条件下的协同燃烧行为及其作用机制。结果表明,污泥经过水热处理后其有机结构和燃烧行为均提升至与煤相似的水平,该过程不仅改善污泥的燃烧特性,并增强其与煤之间的协同燃烧效应。水热污泥中适量的轻质组分与(碱)碱土金属能在混合燃烧过程中加速煤的失重速率,其对三种煤的促进作用可达4.4%-16.1%(褐煤)、1.9%-9.4%(烟煤)和4.8%-12.1%(无烟煤)。总体而言,水热污泥与褐煤混合而成的燃料在燃料性能上具有较大的优势,并且其混合比例以30%(水热污泥):70%(褐煤)与50%(水热污泥):50%(褐煤)为宜。     

污泥与煤共热解过程中磷元素的挥发规律研究

污泥灰分中磷元素含量明显高于煤,其中主要的晶体态含磷化合物为磷酸铁钙和少量的磷酸铝。利用高频加热反应装置考察了污泥-神府煤混合物快速热解过程中磷元素挥发规律。结果表明,污泥-神府煤混合物热解后磷元素主要存在于热解焦中。磷元素挥发比例随污泥添加比例的增加先升高后降低,随热解温度的升高而增加。热解温度不高于1 100 ℃时,混合物中以有机磷的挥发为主,磷元素挥发比例不高于3.2%。热解温度高于1 200 ℃后无机磷中磷元素挥发明显,1 300 ℃下最高有33.0%的磷元素随热解气体挥发出。     

污泥干燥预处理后与神府煤共成浆性的研究

以萘系阴离子表面活性剂为分散剂,考查了污泥干燥条件和粒径对神府煤成浆性的影响。结果表明,将污泥干燥后再制浆,明显提高了污泥煤浆的成浆浓度;升高干燥温度,有利于提高污泥煤浆的成浆浓度。干燥温度对污泥的可磨性影响较大。干燥温度越高,干燥污泥可磨性越好,球磨的污泥平均粒径越小,制得的污泥煤浆表观黏度越低;温度高于105℃,污泥的可磨性无明显差别,污泥煤浆的表观黏度亦无明显变化。污泥粒径越小,颗粒越细,一定程度上提高了煤粉的堆积效率,使污泥煤浆的表观黏度降低。     

生物质与煤混燃灰的比电阻特性实验研究

以玉米秸、麦秸、锯末纯燃并以不同比例与煤混燃,利用DR型高压粉尘比电阻实验台对灰样比电阻R进行测量, 以AAS对灰样化学成分进行分析。结果表明,纯生物质燃料灰R值为10⁸Ω·cm~10¹0Ω·cm,属于中比电阻。混燃灰样的R值均为10⁸Ω·cm~10¹2Ω·cm。麦秸与煤的混燃灰中,掺混率R_t对比电阻R的影响不明显;玉米秸与煤的混燃灰中,在110℃以下,R_t越高,R越低;在110℃以上,R_t越高,R越大。生物质与煤的混燃改变了燃料的燃烧特性及熔融特性,使灰的物理特性和化学成分、含量发生变化,造成混燃灰比电阻与煤灰比电阻的规律存在一定的差异。     

Thermogravimetric study of aerobic biodegradation of sanitary sewage sludge and lubricating oil

The present study describes the aerobic biodegradation process of a mixture of sanitary sewage sludge and lubricating oil. TG/DTG curves confirmed that the applied aerobic biological treatment decreased the organic material content and caused significant modifications in the thermal behavior of the studied substrates after the functioning period.     

污水污泥空气气化特性的研究

利用外热式下吸固定床气化实验装置,以空气为气化剂对五种不同性质污泥的气化特性进行了研究。结果表明,升高气化温度有利于提高气化气的品质,气化气中CO、CH₄和H₂的含量和气化气热值随气化剂流量的减小而增加。污泥厌氧消化过程使气化气品质降低;污水处理工艺对污泥气化气组成和热值亦产生影响,其中连续SBR工艺的未消化污泥气化气中CO、CO₂的含量最高,而H₂、CH₄和C_mH_n的含量最低;活性污泥法的未消化污泥气化气中H₂和C_mH_n含量最高;A²/O工艺的未消化污泥气化气中CO、CO₂的含量最低,而CH₄的含量最高,且三个污水工艺污泥的气化气热值依次升高。     

一种煤与两种城市污水污泥混合热解的热重分析

采用热重分析法对一种煤和两种城市污水污泥（S1和S2）及其混合物进行了热解实验研究,揭示了煤和污泥在氮气中的热解特性及污泥对煤热解特性的影响。煤和污泥的热解特性参数不同,主要表现在总失重率、失重速率及挥发分析出温度区间等。煤与污泥S1混合有助于增加样品的热解总失重率,提高失重速率;污泥S1与煤的挥发分析出区间部分重合,污泥灰中含的无机物对煤的热解起到催化效果;煤和S2污泥混合后热解反应过程中无明显相互作用;煤与城市污水污泥混合物的相互作用与样品特性和混合比例有关。     

高效液相色谱-质谱联用法同步测定城市污水处理厂活性污泥中的多类抗生素残留

采用超声萃取、固相萃取及高效液相色谱-质谱联用技术(LC-MS),建立了活性污泥中3类共9种抗生素(包括5种磺胺类、3种四环素类及1种大环内酯类)的同时分析方法.样品经甲醇-Na2,EDTA/Mcllvaine缓冲液(1∶1,体积比)超声萃取,HLB固相萃取柱净化富集后,以Symmetry C18反相柱为分析柱,0.2...     

Gas chromatographic-mass spectrometric study of the oil fractions produced by microwave-assisted pyrolysis of different sewage sludges

The pyrolysis of sewage sludge was studied in a microwave oven using graphite as microwave absorber. The pyrolysis temperature ranged from 800 to 1000 degrees C depending on the type of sewage sludge. A conventional electrical furnace was also employed in order to compare the results obtained with both methods. The pyrolysis oils were trapped in a series of condensers and their characteristics such as elemental analysis and calorific value were determined and compared with those of the initial sludge. The oil composition was analyzed by GC-MS. The oils from the microwave oven had n-alkanes and 1-alkenes, aromatic compounds, ranging from benzene derivatives to polycyclic aromatic hydrocarbons (PAHs), nitrogenated compounds, long chain aliphatic carboxylic acids, ketones and esters and also monoterpenes and steroids. The oil from the electric oven was composed basically of PAHs such as naphthalene, acenapthylene, phenanthrene, fluoranthene, benzo[a]anthracene, benzofluoranthenes, benzopyrenes, indenepyrene, benzo[ghi]perylene, and anthanthrene. In contrast, these compounds were not produced in the case of microwave-assisted pyrolysis.     

The effect of acid treatment on the pyrolysis behavior of sewage sludges

One sewage sludge (SLA) from Ávila region (Spain) was selected and used as raw material in order to study the influence of acid treatment on the pyrolysis behavior of sewage sludges. SLA was heat treated with acid solutions at pH 1 and pH 2 leading to SLA-1 and SLA-2, respectively. Characterization of samples has showed that acid treatment leads to metals removal and modifications in the organic matter composition of sewage sludge. Pyrolysis of three samples showed that SLA and SLA-1 have a similar pyrolysis behavior whereas SLA-2 shows a slightly extended temperature interval for pyrolysis, beginning at lower temperature and finishing at higher temperatures.     

Pyrolysis study of sewage sludge by TG-MS and TG-GC-MS coupled analyses

The pyrolysis of an urban plant sewage sludge carried out under He atmosphere was studied by thermogravimetric-mass spectrometric (TG-MS) and thermogravimetric-gas chromatographic-mass spectrometric (TG-GC-MS) analyses. The sludge was thermally degraded with a heating rate of 10°C min^–1 in the 20–1000°C interval; its mass loss is 51.8% up to 600°C and 61.4% up to 1000°C. Gas chromatographic analyses of the gas released during major thermogravimetric events allow the identification of various chemical species. Water, carbon mono- and di-oxide, several hydrocarbons (up to C5, both saturated and unsaturated) were the major detected species. Minor amount of pollutant species, such as cyano-compounds, were also detected. Among the released species hydrocarbons constituted the major fraction (53%), thus suggesting their immediate exploitation as fuel gas. The pyrolysis behaviour of this sample was then compared with other sewage sludge arising from wastewater treatment plants subjected to anaerobic digestion as found in literature data.     

Mass spectrometric study of organocyclosiloxanes

Organocyclosiloxanes of various chemical structures were studied by mass spectrometry using different ionization methods. The electron ionization mass spectra contain no peaks of molecular ions, and the main fragment ions are formed due to complicated rearrangements in a molecular ion, which provides no comprehensive view about the molecular structure. The desorption spectra exhibit peaks of quasimolecular and fragment ions, which characterize both molecular weights and chemical structures of the compounds under study. Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1746–1749, September, 2007.