Effects of adding chicken manure to cattle manure on aerobic compost process parameters at low temperature

The research was aimed at studying the effect of adding certain proportion chicken manure to cattle manure on compost below 0℃ with aerobic compost method, which was suitable for northern cold climate. The results indicated that the mixed compost completed 3 days earlier than the single compost, the temperature of the mixed compost rose to 50.7℃ at the 1st day,and achieved its highest temperature 74.4℃ at the 3rd day. The temperature of the single compost rose to 40.0℃ at the 1st day,rose to 55.6℃ at the 3rd day,and achieved its highest temperature 70.1℃ at the 5th day. Adding chicken manure had no impact on the variety trend of the process parameters such as moisture content, pH and C/N ratio, hut increased the variety range of these parameters.

Kinetics model of aerobic phase in hybrid anoxic-oxic process

Kinetics models of COD degradation,biomass growth of the anoxic-oxic ( A/O) system as well as NH3-N degradation in aerobic phase were presented according to the mass balance theory,reaction-diffusion theory and Fick law. Then these models were testified by comparson with experimental results. It is demonstrated that the variation trends of theoretical and experimental values for COD degradation and biomass growth are similar. The deviation rate between theoretical and experimental values is always under 20% even it increases along with the fluctuation of influent organic loading. In terms of NH3-N degradation,nitrification can also be well simulated by the model as the substrates of influent are sufficient. It indicates that the model can accurately reflect the reaction in hybrid A/O process. Models presented herein provide a theoretical basis for the design, operation and control of hybrid A/O process.

Multi-stage Process of the Bulqiza Chromitites, Eastern Ophiolitic Belt, Albania

The ultramafic massif of Bulqiza,which belongs to the eastern ophiolitic belt of Albania,is the most important area for metallurgical chromitite ores.The massif consists of a thick(>4 km)rock sequence,with a generalized

Removal of nitrogen and phosphorus in a combined A^2/O-BAF system with a short aerobic SRT

A bench-scale anaerobic/anoxic/aerobic process-biological aerated filter （A^2/O-BAF） combined system was carded out to treat wastewater with lower C/N and C/P ratios. The A^2/O process was operated in a short aerobic sludge retention time （SRT） for organic pollutants and phosphorus removal, and denitrification. The subsequent BAF process was mainly used for nitrification. The BAF effluent was partially returned to anoxic zone of the A^2/O process to provide electron acceptors for denitrification and anoxic P uptake. This unique system formed an environment for reproducing the denitdfying phosphate-accumulating organisms （DPAOs）. The ratio of DPAOs to phosphorus accumulating organisms （PAOs） could be maintained at 28% by optimizing the organic loads in the anaerobic zone and the nitrate loads into the anoxic zone in the A^2/O process. The aerobic phosphorus over-uptake and discharge of excess activated sludge was the main mechanism of phosphorus removal in the combined system. The aerobic SRT of the A^2/O process should meet the demands for the development of aerobic PAOs and the restraint on the nitrifiers growth, and the contact time in the aerobic zone of the A^2/O process should be longer than 30 min, which ensured efficient phosphorus removal in the combined system. The adequate BAF effluent return rates should be controlled with 1--4 mg/L nitrate nitrogen in the anoxic zone effluent of A^2/O process to achieve the optimal nitrogen and phosphorus removal efficiencies.

Springback analysis and strategy for multi-stage thin-walled parts with complex geometries

Springback of a SUS321 complex geometry part formed by the multi-stage rigid-flexible compound process was studied through numerical simulations and laboratory experiments in this work.The sensitivity analysis was provided to have an insight in the effect of the evaluated process parameters.Furthermore,in order to minimize the springback problem,an accurate springback simulation model of the part was established and validated.The effects of the element size and timesteps on springback model were further investigated.Results indicate that the custom mesh size is beneficial for the springback simulation,and the four timesteps are found suited for the springback analysis for the complex geometry part.Finally,a strategy for reducing the springback by changing the geometry of the blank is proposed.The optimal blank geometry is obtained and used for manufacturing the part.

Kinetics of aerobically activated sludge on terylene artificial silk printing and dyeing wastewater treatment

Aerobically activated sludge processing was carried out to treat terylene artificial silk printing and dyeing wastewater (TPD wastewater) in a lab-scale experiment, focusing on the kinetics of the COD removal.The kinetics parameters determined from experiment were applied to evaluate the biological treatability of wastewater.Experiments showed that COD removal could be divided into two stages,in which the ratio BOD/COD (B/C) was the key factor for stage division.At the rapid-removal stage with B/C>0.1,COD removal could be described by a zero order reaction. At the moderate-removal stage with B/C<0.1,COD removal could be described by a first order reaction. Then Monod equation was introduced to indicate COD removal. The reaction rate constant (K) and half saturation constant (Ks) were 0.0208-0.0642L/(gMLSS)h and 0.44-0.59(gCOD)/L respectively at 20℃-35℃.Activation energy (Ea) was 6.05×10^4 J/mol.By comparison of kinetic parameters, the biological treatability of TPD wastewater was superior to that of traditional textile wastewater.But COD removal from TPD-wastewater was much more difficult than that from domestic and industrial wastewater,such as papermaking, beer, phenol wastewater, etc.The expected effluent quality strongly related to un-biodegradable COD and kinetics rather than total COD. The results provide useful basis for further scaling up an defficient operation of TPD wastewater treatment.

Microbial Function, Enzymatic Activities and Diversity in an Anaerobic-Anoxic-Aerobic Reactor System

Enzymatic activities of beta-glucosidase (β-GLC), leucine-aminopeptidase (LAP), and alkaline phosphatase (APA), corresponding to nutrient eliminations, and the microbial community structures were analyzed in an anaerobic-anoxic-aerobic reactor system. Results showed that most activity of β-GLC (64.2 μmol/(L·h)) associated with the largest fraction of small-molecular-weight carbohydrates was found in the aerobic reactor, indicating the existence of coupled hydrolysis-uptake mechanism in the aerobic bacteria. Similar activities of LAP presented in the anoxic and aerobic environments, whose increases accompanied by increments in nitrogen uptake rates greatly accelerated the processes of aerobic nitrification and anoxic denitrification. The highest APA activity displayed in the anaerobic reactor, however, dephosphorization performance was mainly achieved under aerobic condition. Microbial community fingerprints generated by polymerase chain reaction amplification and denaturing gradient gel electrophoresis (PCR-DGGE) revealed that Proteobacterium, Actinobacterium, and Nitrospira were the predominant classes in the activated sludge and there was no evidence of community variations among each function reactor in the system with biomass recycling.

鸡粪堆肥过程中氮素损失研究综述

好氧堆肥是实现鸡粪资源化处理最主要的技术手段之一。然而在鸡粪堆肥过程中氮素损失较为严重,在降低肥效的同时,还引起严重的面源污染。本文总结影响鸡粪堆肥过程氮素损失的主要原因,并综述初始C/N、初始含水率、翻堆频率、添加剂种类对鸡粪堆肥过程氮素损失的影响,得出减少鸡粪堆肥氮素损失的最适初始C/N为20~25、初始含水率为60%~65%、翻堆频率为7天1次。复合添加剂较单一添加剂更能降低堆肥过程中的氮素损失。最后提出鸡粪堆肥未来方向的研究展望,为今后进行鸡粪堆肥过程中氮素损失的研究提供理论依据。

苯酚对好氧颗粒污泥处理建筑涂料废水的影响及机制

苯酚是建筑涂料常被使用的物质,然而苯酚对好氧颗粒污泥(AGS)处理建筑涂料废水过程内污泥颗粒化进程及运行效能的影响很少被研究。为填补相关研究工作空白,本研究考察了苯酚浓度对AGS处理建筑涂料废水过程内污泥颗粒化及运行效能的影响并分析了相关机制。结果表明低于0.2 mg/L苯酚对AGS影响不明显,而超过2.0 mg/L苯酚降低了AGS颗粒化进行并降低了AGS处理建筑涂料废水的效能。机制分析表明高浓度苯酚降低了AGS内污泥浓度,并减少了有机质占比,此外高浓度苯酚提高了胞外聚合物(EPS)包括SB-EPS和LB-EPS的含量。超过2.0 mg/L苯酚降低了AGS处理废水的运行效能,其在20.0 mg/L苯酚组别内,COD、NH_(4)^(+)-N和总氮(TN)去除率下降至81.6%~83.5%、81.6%~84.5%和50.8%~51.9%。此外,高浓度苯酚降低了比耗氧速率,降低了微生物代谢,进而导致营养盐去除受抑制。研究结果为AGS处理含苯酚的建筑涂料废水提供了一定的数据支撑。

高效包埋好氧颗粒污泥在农药废水处理中的应用研究

为了高效处理有毒有害的农药废水,研究了包埋好氧颗粒污泥对实际农药废水的处理效果,并对比了包埋好氧颗粒污泥、市政好氧污泥及两者混合体系在实际农药废水活性污泥法处理中的表现。结果表明:在实际农药废水处理中,市政好氧污泥的硝化速率和COD降解速率分别为0.67 mg[N]/(g[SS]·h)和3.54 mg[COD]/(g[SS]·h),两者混合体系的平均硝化速率和COD降解速率分别为5.0 mg[N]/(g[包埋颗粒]·h)和49.05 mg[COD]/(g[包埋颗粒]·h),而包埋好氧颗粒污泥的平均COD降解速率为91.14 mg[COD]/(g[包埋颗粒]·h),并且具有更好的硝化性能,平均硝化速率为18.8 mg[N]/(g[SS]·h)。包埋好氧颗粒污泥对农药废水表现出较强的耐冲击负荷能力,说明了包埋好氧颗粒污泥的投加对提高农药废水氨氮降解效果显著。

Synergistic catalysis of the N-hydroxyphthalimide on flower-like bimetallic metal-organic frameworks for boosting oxidative desulfurization

Synergic catalytic effect between active sites and supports greatly determines the catalytic activity for the aerobic oxidative desulfurization of fuel oils.In this work,Ni-doped Co-based bimetallic metal-organic framework(CoNi-MOF)is fabricated to disperse N-hydroxyphthalimide(NHPI),in which the whole catalyst provides plentiful synergic catalytic effect to improve the performance of oxidative desulfurization(ODS).As a bimetallic MOF,the second metal Ni doping results in the flower-like morphology and the modification of electronic properties,which ensure the exposure of NHPI and strengthen the synergistic effect of the overall catalyst.Compared with the monometallic Co-MOF and naked NHPI,the NHPI@CoNi-MOF triggers the efficient activation of molecular oxygen and improves the ODS performance without an initiator.The sulfur removal of dibenzothiophene-based model oil reaches 96.4%over the NHPI@CoNi-MOF catalyst in 8 h of reaction.Furthermore,the catalytic product of this aerobic ODS reaction is sulfone,which is adsorbed on the catalyst surface due to the difference in polarity.This work provides new insight and strategy for the design of a strong synergic catalytic effect between NHPI and bimetallic supports toward high-activity aerobic ODS materials.

好氧颗粒污泥处理锅炉脱硫废水的性能及机制探究

为了探究好氧颗粒污泥(AGS)对锅炉脱硫废水处理效能及作用机制,以AGS和锅炉脱硫废水为探究对象,构建了AGS和传统A~2/O工艺,在中温条件下比较了AGS和传统A~2/O工艺对锅炉脱硫废水处理效能的影响,并解析相关作用机制。结果表明,相较于传统A~2/O工艺,AGS处理锅炉脱硫废水具有更优的污染物和营养盐去除,在AGS工艺内,化学需氧量(COD)、NH_(4)^(+)-N和总氮(TN)的去除率分别高达94.6%~97.8%、94.3%和74.3%。AGS工艺内胞外聚合物(EPS)含量高于传统A~2/O工艺。在内聚物聚羟基脂肪酸酯(PHA)富集方面,AGS展示出更大富集量,可高达5.87 mmol/g,但糖原质的代谢水平下降。AGS内微生物群落主要是Proteobacteria、Bacteroidetes、Firmicutes,其中Bacteroidetes和Nitrospirae的相对丰度显著高于传统A~2/O工艺。研究结果为锅炉脱硫废水的高效处理提供一定的技术支撑。

不同工艺处理辛辣类调味品废水及辣椒素抑制性研究

针对辛辣类调味品废水对微生物产生抑制导致生化处理困难的现状,进行了AAOO短时好氧工艺与A^(2)O工艺的中试实验,比较2种工艺在去除COD、NH_(4)^(+)-N、TP上的差异,并研究了辣椒素对未强化活性污泥的抑制作用。结果表明:AAOO短时好氧工艺较A^(2)O工艺处理辛辣类调味品废水优势明显,对COD、NH_(4)^(+)-N、TP和辣椒素的平均去除率分别达到95.6%、90.1%、96.7%和90.9%;AAOO短时好氧工艺分池培养优势菌种以实现高效脱氮除磷,装置连续稳定运行80 d,出水COD、NH_(4)^(+)-N、TP数值稳定在55、6.5、0.5 mg/L以下,满足GB 8978-1996中一级排放标准;AAOO装置出水生物抑制性物质浓度稳定在0.6 mg/L以下,说明该工艺对辣椒素类废水有一定的抗冲击能力。研究结果可为处理辛辣类废水提供重要参考及AAOO短时好氧工艺的应用提供思路。

好氧脱氮菌剂的制备及其强化餐厨废水脱氮研究

针对餐厨废水高有机物、高氨氮的问题,采用计算机辅助菌种选择技术从餐厨垃圾中分离得到了好氧脱氮菌株。试验结果:在培养温度为35℃、间歇震荡和培养时间108 h的条件下,好氧脱氮菌株在培养液中的活菌数达到8.83×10^(7) cfu/mL。在SBR反应器中加入自制的含有菌剂的污泥,反应器出水氨氮去除率达到82.10%~87.92%,与未加菌剂时的氨氮去除率62.37%~68.65%相比脱氮率提升了19.5%,表明本研究的好氧脱氮菌剂对废水脱氮具有强化效果。

A novel multistage anoxic/aerobic process with sludge regeneration zone (R-MAO) for advanced nitrogen removal from domestic sewage

To achieve advanced nitrogen removal from actual municipal sewage,a novel multistage anoxic/aerobic process with sludge regeneration zone(R-MAO)was developed.The reactor was used to treat actual domestic sewage and the nitrogen removal capacity of the sludge regeneration zone(R zone)was investigated during the long-term operation.The best performance was obtained at the R zone’s Oxidation-Reduction Potential(ORP)of-50±30 mV and hydraulic residence times(HRT)of 1.2 hr.The average effluent COD,TN,NH_(4)^(+)-N and NO_(3)^(−)-N of the R-MAO process were 18.0±2.3,7.5±0.6,1.0±0.5 and 4.6±0.4 mg/L,respectively,with the corresponding removal efficiency of COD,TN and NH_(4)^(+)-N were 92.9%±1.0%,84.1%±1.5% and 97.5%±1.1%.Compared to the sole MAO system,the TN removal efficiency of the R-MAO increased by 10.1%.Besides,under the optimal conditions,the contribution of the R zone in the R-MAO that removal COD,TN,NH_(4)^(+)-N and NO_(3)^(−)-N were 0.36,0.15,0.032 and 0.82 g/day.High-throughput sequencing results showed that uncultured_bacterium_f_Burkholderiaceae(5.20%),OLB8(1.04%)and Ottowia(1.03%)played an important role in denitrification in the R zone.This study provided effective guidance for the design and operation of the R-MAO process in domestic sewage treatment.

A novel predict-prevention quality control method of multi-stage manufacturing process towards zero defect manufacturing

Zero defection manufacturing (ZDM) is the pursuit of the manufacturing industry. However, there is a lack of the implementation method of ZDM in the multi-stage manufacturing process (MMP). Implementing ZDM and controlling product quality in MMP remains an urgent problem in intelligent manufacturing. A novel predict-prevention quality control method in MMP towards ZDM is proposed, including quality characteristics monitoring, key quality characteristics prediction, and assembly quality optimization. The stability of the quality characteristics is detected by analyzing the distribution of quality characteristics. By considering the correlations between different quality characteristics, a deep supervised long-short term memory (SLSTM) prediction network is built for time series prediction of quality characteristics. A long-short term memory-genetic algorithm (LSTM-GA) network is proposed to optimize the assembly quality. By utilizing the proposed quality control method in MMP, unqualified products can be avoided, and ZDM of MMP is implemented. Extensive empirical evaluations on the MMP of compressors validate the applicability and practicability of the proposed method.

好氧颗粒污泥技术处理化工园区工业污水

采用好氧颗粒污泥技术处理化工园区企业排放的工业污水,实现了污泥颗粒化。工艺启动和可靠性研究结果表明,直径不小于0.2 mm的球形或椭球形致密颗粒污泥占比约60%,为橙黄色,SV5接近300 mL/L。在冬季不加任何化学药剂的情况下,出水总氮小于10 mg/L。该技术运行平稳,水质波动适应性强,操作弹性大,吨水电耗为0.23 kW·h,与传统的A^(2)O相比,能耗节约明显,同时占地面积显著减小。

农业废弃物好氧发酵高温阶段工艺

以优化好氧发酵高温阶段工艺为目的,采用鸡粪和玉米秸秆为原料,选取高温阶段温度、时间、菌剂添加量为工艺参数进行单因素试验和正交试验,以酸碱度(pH)、电导率(EC)、碳氮比(C/N)和种子发芽指数为评价指标,对农业废弃物高温好氧发酵中高温阶段工艺开展研究。结果表明,高温阶段最佳工艺条件为菌剂添加量20 g/kg、温度75℃、发酵时间12 h。

污水生化处理工艺发展阶段化技术特征及未来趋势

百余年来,伴随人类社会和科技日新月异,污水生化处理技术也在实现快速发展与不断迭代,新工艺与新反应器、新功能微生物与新生化代谢途径不断被提出、发现和解析,并进一步推动了污水处理技术的进步与升级。回顾了过去百余年污水生化处理技术发展历程,就典型污水生化工艺,结合技术研发进展、技术成熟度及案例应用情况,给出了不同生化处理工艺代际划分与技术发展期“S曲线”,分析了近些年来新涌现出的一些革新性污水生化处理工艺的技术原理、技术特征,结合实际案例分析了工艺技术特征、技术优势与总体效能,从工艺强化、绿色低碳与集约高效等方面总结了未来污水处理发展的技术趋势,以期为“双碳背景”下排水系统提质增效工作、未来国内前瞻性污水厂工艺设计与运行提供参考和借鉴。

一体化设备堆肥处理园林绿化废弃物的工艺研究

随着北京市环境建设水平的提高,林地绿地面积持续增加,园林绿化废弃物产生量也不断增长。好氧堆肥能够将园林绿化废弃物分解转化成腐殖质,实现“落叶化土”“枯枝还田”。对一体化设备堆肥处理园林绿化废弃物的工艺参数进行了研究,获得了一体化设备处理园林绿化废弃物的最优工艺参数:(1)曝气:通风量为6 m^(3)/h,曝气间隔25 min,曝气时长5 min;(2)搅拌:堆肥的第4 d对物料搅拌1次;(3)粒径:树枝废弃物的最佳粒径为10~30 mm;(4)微生物菌剂:C/N为30~50时,微生物菌剂添加比例不低于4%。将研究成果用于示范工程中检测应用效果,结果表明:研究获得的工艺参数能有效指导实践,园林绿化废弃物堆肥15 d达到腐熟。