强化污泥厌氧消化的前处理技术研究进展

厌氧消化前采用不同的预处理方法是增强厌氧消化性能的关键,预处理能促进污泥内微生物细胞的分解,加速胞内物质的释放,加快污泥的水解速率.综述了当前研究和应用较多的物理、化学和生物法等污泥预处理技术,如热处理、冻融法、超声波处理法、酸碱法、加盐法、凝聚与絮凝调理、生物酶处理等,分析了各种方法的原理、特点和处理效果.     

超声波对污泥脱水及厌氧消化影响的研究进展

超声波技术作为污泥厌氧消化预处理手段被广泛关注.超声波能改变污泥的性质,改善污泥厌氧消化的性能,但是其处理效果受到频率、强度、作用时间和发生方式等因素的影响,只有在合适的条件下,预处理效果才能达到最佳.本文着重介绍了超声波的频率、强度、作用时间和发生方式对污泥脱水性能、污泥沉降性能、微生物活性和污泥产气等多方面的影响.由于脱水性能和厌氧消化的改善所需要超声波的条件不一样,所以有必要通过进一步实验使预处理效果最优化;同时,为了进一步降低能耗,有效利用超声波与其它预处理技术相结合将是未来的研究方向.     

改善污泥厌氧消化性能的预处理技术

厌氧消化是污泥稳定化处理的主要技术之一。通过采用一定的预处理技术,破坏细胞结构,释放有机质,促进污泥的水解速率,从而改善污泥厌氧消化性能。该文综述了几种国内外目前研究较为广泛的预处理技术,主要包括热预处理法、转动球磨法、高压喷射法、超声波预处理法、酸预处理法、碱预处理法和氧化法等技术,并分别探讨了各种技术的作用原理、特点、处理效果及应用前景。     

微波/碱/活性炭纤维联用预处理污泥的厌氧消化效果

试验考察了在碱性条件下,以活性炭纤维为催化剂,微波诱导氧化预处理对污泥厌氧消化效果的影响。试验结果表明,预处理能有效地提高污泥的厌氧消化性能。经过预处理后,污泥在厌氧消化过程中平均日产气速率是50.5mL/d,比原污泥增加了64%;污泥总产气量比未预处理前增加了63.7%;厌氧消化后污泥的总COD去除率达到50.4%,比未经过预处理的大10.4%。消化过程中污泥单位VSS的产气率由没经过预处理的215.7mL/gVSS提高到272.2mL/gVSS。     

微波预处理剩余污泥的研究进展

介绍了微波预处理污泥的作用机理及作用过程,包括污泥絮体破解、污泥细胞破碎及有机物的释放、有机物水解、美拉德反应等,总结了微波预处理污泥的作用效果（物理特性、化学特性、生物特性）、影响微波预处理效果的因素（污泥特性、处理条件）和微波预处理污泥对其后续厌氧消化的影响。指出了目前研究中存在的主要问题是试验规模偏小,预处理方式为间歇处理,在对污泥中有毒有害有机物和病原微生物的去除研究方面还需加强。提出今后应重点开展微波组合工艺对污泥中有毒有害有机物和病原微生物去除的基础研究,同时积极开发相关设备,开展微波预处理污泥的连续和中试研究,推动微波技术在污泥资源化、减量化和无害化处理中的应用。     

水热预处理对剩余污泥有机物释放的影响

针对剩余污泥中有机能源利用率低的问题,研究了水热预处理对剩余污泥有机物释放及污泥厌氧消化过程中累积产气量的影响。结果表明:水热处理是一种有效的污泥预处理方法,当水热温度为200℃、水热时间为1 h时,污泥减量度达76.56%,污泥SCOD为原泥的34倍,大大减少了污泥固相有机物含量。经水热处理后,污泥厌氧消化最大产气量为2 950 m L,较原泥提高了69%;厌氧消化后,水热预处理污泥SCOD减少量为原泥的30倍。     

剩余污泥消化后预处理高浓度生产废水

将好氧装置的剩余污泥加入污泥消化池,当池内污泥变黑并探测到有可燃气体时,加入生活污水和生产废水对消化污泥进行培养驯化,培养驯化期间应逐步减小生活污水水量,增加高浓度生产废水水量.用经过驯化的消化污泥预处理生产废水,有机物的去除率＞30%,pH也由5～6被提高到7以上.将好氧装置产生的剩余污泥消化后预处理高浓度的生产废水,剩余污泥被再利用,并且也有利于降低整套污水处理装置的运行成本.     

污泥厌氧消化预处理技术综述

综述了目前研究比较广泛的污泥预处理技术,包括酸碱法、超声波法、热解法、γ-射线辐照法、臭氧氧化法、高铁酸钾氧化法、电化学氧化法、生物酶法以及联合法等技术,分别分析了它们的原理、特点、处理效果以及应用前景。     

污泥厌氧消化预处理技术综述

综述了目前研究比较广泛的污泥预处理技术,包括酸碱法、超声波法、热解法、γ-射线辐照法、臭氧氧化法、高铁酸钾氧化法、电化学氧化法、生物酶法以及联合法等技术,分别分析了它们的原理、特点、处理效果以及应用前景.     

城市污水处理厂剩余污泥厌氧消化试验研究

探讨了影响污泥厌氧消化的各种因素,包括温度、pH值、污泥投配率、有机负荷等,以期寻找出最佳的污泥厌氧消化条件,获得最高的污泥降解率和最高的产气量;为比较不同停留时间和有机负荷对污泥厌氧消化效率的影响,实验中维持进料含固率不变,探讨相关的污泥厌氧消化效率。     

浅议城市污水处理厂污泥处理技术路线

通过分析我国城市污水处理厂产生的不同类型污泥的特性,介绍了污泥"减量化"、"无害化"和"资源化"的技术措施及三者之间的关系,重点对减量化的工艺予以综述,提出了不同的减量化理念。在污泥资源化利用方面,通过详细介绍3个典型的污泥处理案例,将厌氧消化产沼气工艺、高温热水解-厌氧消化联合工艺和建材化水泥窑煅烧工艺进行了对比,阐述了不同工艺具有的优缺点。     

剩余污泥厌氧发酵制氢效率的研究进展

剩余污泥中存在大量的微生物,微生物的细胞质富含丰富的有机质(包括糖、蛋白质和脂肪等),但微生物的细胞质被细胞壁包裹,限制了污泥的厌氧发酵。想要改变污泥中有机物的可利用性,必须采用适当的预处理技术,破坏细菌的细胞壁使有机质溶出,以利于后续厌氧发酵产氢。系统介绍了物理﹙微波、超声波和热预处理﹚、化学﹙酸、碱预处理﹚、生物﹙酶预处理﹚等预处理方式及其他因素对污泥厌氧发酵产氢率的影响。     

污水厂污泥厌氧消化产短链脂肪酸研究进展

污泥厌氧消化产短链脂肪酸是实现污泥资源化的重要途径,短链脂肪酸不仅是产甲烷的底物、污水脱氮除磷的碳源,而且可以作为原料产生一系列高附加值的产品。本文介绍了污泥厌氧消化产有机酸的机理,重点阐述了污泥性质、温度、pH值、碳氮比（C/N）、水力停留时间（HRT）和固体停留时间（SRT）等影响污泥厌氧消化产酸的主要因素及研究进展,指出这些因素通过改变底物性质、微生物活性及二者接触反应时间等对产酸过程产生影响,其中温度和pH值是研究热点,目前大多数研究者认为高温和碱性条件更有利于污泥产酸。此外,还论证了这些影响因素对于实现污泥产酸最大化的重要意义,提出各因素之间的相互关系以及通过调控温度、pH值、碳氮比等发酵影响因素来控制产酸类型是今后值得研究的方向。     

草屑厌氧消化预处理耦合水热炭化研究

厌氧消化（AD）耦合水热炭化（HTC）技术对园林废弃物的可持续资源化利用具有显著优势和意义。采用草为研究对象,进行了7~28 d的AD预处理,深入探究了AD预处理耦合HTC对水热炭特性及其热解和产物释放特性的影响。其中,AD促进HTC过程主要发生脱羧反应;通过改变木质纤维素构成比例和结构特征有效调控水热炭的功能特性。此外,AD打破了生物质内部致密的刚性结构,促进了水热炭丰富孔隙的形成和比表面积的增加。在生物可降解程度为17.52%（AD 7 d）时,水热炭性能最佳,质量产率、高位热值（HHV）、能量产率和能量密度分别达62.75%、23.81 MJ·kg^-1、80.31%和1.28。此外, TG-MS分析结果揭示了AD预处理提高了炭的热稳定性以及热解产物中能源气体的生成,有助于热解气的提质和利用。     

Effect of ultrasonic assisted KOH pretreatment on physiochemical characteristic and anaerobic digestion performance of wheat straw

In this study, ultrasonic field was applied during potassium hydroxide (KOH) pretreatment of wheat straw (WS). Three concentrations of KOH (2%, 4%, and 6%) were tested during pretreatment. The results showed that there was a significant influence of the ultrasonic assisted KOH pretreatment (KOH_Upt) on physiochemical characteristics of WS during pretreatment as well as on digester performance. The pretreatment time was optimized to 36 h for all KOH concentrations. The highest total volatile fatty acid (TVFA) productions (3189 mg·L⁻¹) from 6%KOH_Upt samples were observed. Similarly, the SEM analysis and FTIR observation revealed that KOH_Upt effectively disrupted the physical morphology of WS and successful breaking of lignin and hemicellulose linkage between carboxyl groups. Moreover, the highest biogasification (555 ml·(g VS_loaded)⁻¹) and biomethane productions (282 ml·(g VS_loaded)⁻¹) from 4%KOH_Upt digesters, with 69% of biodegradability, indicated significant availability of organic matter from KOH_Upt. The R² values (0.993–0.998) in Modified Gompertz Model indicated that the model was feasible to predict methane yield for this study. Similarly, the B_o values for 4%KOH_Upt (283.30 ± 2.74 ml·(gVS_loaded)⁻¹) were also in agreement to the experimental methane yield. These results suggested that ultrasonic addition during KOH pretreatment of WS can effectively increase the organic yield during pretreatment. Moreover, the increase in methane production from 4% KOH_Upt suggested that digester performance can be improved with lower KOH concentrations using this pretreatment.     

不同温度下氢氧化钠预处理对玉米秸秆甲烷产量的影响

利用农作物秸秆进行厌氧发酵生产沼气是解决我国农村能源紧张的重要途径,然而秸秆中难以降解的木质纤维结构导致在发酵过程中甲烷转化率较低。利用自行设计的可控性恒温发酵装置,以玉米秸秆为发酵原料,分析了在不同温度条件下氢氧化钠（NaOH）预处理对秸秆木质纤维结构以及厌氧发酵产气效率的影响。结果表明,NaOH预处理能够显著降低玉米秸秆的木质纤维素含量,与未预处理的秸秆相比,经NaOH处理后的秸秆纤维素含量降低了24.4%～33.2%,半纤维素含量降低了14.2%～52.4%,木质素含量降低了9.3%～29.3%。在6%、8%和10%浓度中,经8%NaOH处理的秸秆在55℃下的甲烷产量最高,达到188.7 ml CH₄·（g VS）^-1,较未处理的增加了84.2%,因此可作为提高秸秆厌氧发酵产气效率的预处理方法。     

Effect of ultrasonic assisted KOH pretreatment on physiochemical characteristic and anaerobic digestion performance of wheat straw

In this study, ultrasonic field was applied during potassium hydroxide (KOH) pretreatment of wheat straw (WS). Three concentrations of KOH (2%, 4%, and 6%) were tested during pretreatment. The results showed that there was a significant influence of the ultrasonic assisted KOH pretreatment (KOH_Upt) on physiochemical characteristics of WS during pretreatment as well as on digester performance. The pretreatment time was optimized to 36 h for all KOH concentrations. The highest total volatile fatty acid (TVFA) productions (3189 mg·L^-1) from 6% KOH_Upt samples were observed. Similarly, the SEM analysis and FTIR observation revealed that KOH_Upt effectively disrupted the physical morphology of WS and successful breaking of lignin and hemicellulose linkage between carboxyl groups. Moreover, the highest biogasification (555 ml·(g VS_loaded)^-1) and biomethane productions (282 ml·(g VS_loaded)^-1) from 4%KOH_Upt digesters, with 69% of biodegradability, indicated significant availability of organic matter from KOH_Upt. The R² values (0.993-0.998) in Modified Gompertz Model indicated that the model was feasible to predict methane yield for this study. Similarly, the Bo values for 4%KOH_Upt (283.30 ± 2.74 ml·(gVS_loaded)^-1) were also in agreement to the experimental methane yield. These results suggested that ultrasonic addition during KOH pretreatment of WS can effectively increase the organic yield during pretreatment. Moreover, the increase in methane production from 4% KOH_Upt suggested that digester performance can be improved with lower KOH concentrations using this pretreatment.     

污水处理厂剩余污泥的中温厌氧消化特性研究

对天津某污水处理厂的剩余污泥进行中温厌氧消化试验,研究了在不同HRT下的产气量、有机物去除率等指标,结果表明:剩余污泥经过中温消化,在HRT分别为30、20、10 d时,产气率分别为0.022、0.027、0.033 L/(g[VS].d);CODCr的去除率为18.8%～38.1%;由COD物料衡算得知,基质中40%的固态有机物被分解转化,COD甲烷转化率最高约为32.0%;对剩余污泥基质的元素组成进行分析,经计算推导出基质的模拟分子式为C9.87H16.72O33.81N。研究结果为污水处理厂剩余污泥厌氧消化工艺选择合适的工艺条件提供了理论参考。     

Effect of aerobic pretreatment on anaerobic digestion of olive mill wastewater (OMWW): An ecoefficient treatment

Anaerobic digestion experiments of olive mill wastewater (OMWW) without pretreatment were carried out and signs of inhibition in the biological process were observed after a time equal to 1.5 times the Hydraulic Residence Time (HRT) due to the presence of a high inhibitors concentration in OMWW. Based on these findings, OMWW was subjected to an aerobic pretreatment in order to reduce the concentration of phenolic compounds and decrease Total Chemical Oxygen Demand (TCOD), achieving a reduction of 78% and 90% of the initial polyphenols concentration and 18% and 21% TCOD reduction when the substrate was aerated for 5 and 7 days respectively.Finally, anaerobic digestion experiments using OMWW aerated for 5 and 7 days as substrate were conducted to determine the influence of aeration time on methane yields and TCOD reduction. The results yield 5 days as the aeration time that achieves best results, given that this stabilizes the anaerobic process, can reduce the TCOD by 65% and generates almost 0.39 m³ methane/kg removed TCOD.Anaerobic digestion of OMWW will be economically feasible if the waste is pretreated by aerobic digestion, since the period of return of investment obtained under these conditions does not exceed 6 years.