Enhanced Biogas Production from the Anaerobic Batch Treatment of Banana Peels

Waste disposal management and the energy crisis are important challenges facing most countries.The fruit-processing industry generates daily several tons of wastes,of which the major share comes from banana farms.Anaerobic digestion(AD)technology has been applied to the treatment of wastewater,animal slurry,food waste,and agricultural residues,with the primary goals of energy production and waste elimination.This study examines the effect of organic loading(OL)and cow manure(CM)addition on AD performance when treating banana peel waste(BPW).The maximum daily biogas production rates of banana peels(BPs)with a CM content of 10%,20%,and 30%at 18 and 22 g of volatile solids(gvs)per liter were 50.20,48.66,and 62.78 mL (gvs.d)^-1 and 40.49,29.57,and 46.54 mL (gvs.d)^-1,respectively.However,the daily biogas yield showed no clear interdependence with OL or CM content.In addition,a kinetic analysis using first-order and cone models showed that the kinetic parameters can be influenced by the process parameters.

Nitrous Oxide Production in a Sequence Batch Reactor Wastewater Treatment System Using Synthetic Wastewater

The rate of nitrous oxide emission from a laboratory sequence batch reactor (SBR) wastewater treatment system using synthetic wastewater was measured under controlled conditions. The SBR was operated in the mode of 4 h for aeration, 3.5 h for stirring without aeration, 0.5 h for settling and drainage, and 4 h of idle. The sludge was acclimated by running the system to achieve a stable running state as indicated by rhythmic changes of total N, dissolved oxygen, chemical oxygen demand, NO^-_2, NO^-_3, NH^+_4, pH, and N2O. Under the present experimental conditions measured nitrous oxide emitted from the off-gas in the aerobic and anaerobic phases, respectively, accounted for 8.6%-16.1% and 0-0.05% of N removed, indicating that the aerobic phase was the main source of N2O emission from the system. N2O dissolved in discharged water was considerable in term of concentration. Thus, measures to be developed for the purpose of reducing N2O emission from the system should be effective in the aeration phase.

Pretreatment of coking wastewater using anaerobic sequencing batch reactor (ASBR)

A laboratory-scale anaerobic sequencing batch reactor (ASBR) was used to pretreat coking wastewater. Inoculated anaerobic granular biomass was acclimated for 225 d to the coking wastewater, and then the biochemical methane potential (BMP)of the coking wastewater in the acclimated granular biomass was measured. At the same time, some fundamental technological factors, such as the filling time and the reacting time ratio (tf/tr), the mixing intensity and the intermittent mixing mode, that affect anaerobic pretreatment of coking wastewater with ASBR, were evaluated through orthogonal tests. The COD removal efficiency reached 38％～50％ in the stable operation period with the organic loading rate of 0.37～0.54 kg COD/(m3.d) at the optimum conditions of tf/tr, the mixing intensity and the intermittent mixing mode. In addition, the biodegradability of coking wastewater distinctly increased after the pretreatment using ASBR. At the end of the experiment, the microorganism forms on the granulated sludge in the ASBR were observed using SEM (scanning electron microscope) and fluoroscope. The results showed that the dominant microorganism on the granular sludge was Methanosaeta instead of Methanosarcina dominated on the inoculated sludge.

Study on the Treatment Strategy of Batches of the Wounded and Partial First-Aid Procedures in Public Emergencies in Tertiary General Hospitals

Objective: The purpose is to formulate treatment strategies of batches of the wounded and partial first-aid procedures, and further improve the emergency rescue capability of hospitals. Methods: This study analyzed the emergency treatment case that we participated in. In this case, we used various means to start the emergency plan, run the emergency procedures, optimize diagnosis, treatment, and rescue procedures, mobilize medical rescue resources, provide a reference for emergency command decisions, formulate a set of coping strategies of tertiary general hospitals on public emergencies. Results: Through the scientific and effective management of our hospital, 20 wounded have been discharged from the hospital and achieved the ideal effect of zero deaths in the hospital. Conclusions: The new mode of first-aid and health emergency management on the scene of modern disaster needs to find ways to minimize the loss of life and property brought by public emergencies, integrate the various sections of modern disaster medicine, integrate a large number of international and domestic basic and clinical research achievements of disaster first-aid, and upgrade to information, digital system.

Treatment of Wastewater with Modified Sequencing Batch Biofilm Reactor Technology

This paper describes the removal of COD and nitrogen from wastewater with modified sequencing batch biofilm reactor. The strategy of simultaneous feeding and draining was explored.The results show that introduction of a new batch of wastewater and withdrawal of the purified water can be conducted simultaneously with the maximum volumetric exchange rate of about 70%.Application of this feeding and draining mode leads to the reduction of the cycle time, the increase of the utilization of the reactor volume and the simplification of the reactor structure. The treatment of a synthetic wastewater containing COD and nitrogen was investigated. The operation mode of F(D) O ( i.e ., simultaneous feeding and draining followed by the aerobic condition) was adopted. It was found that COD was degraded very fast in the initial reaction period of time, then reduced slowly and the ammonia nitrogen and nitrate nitrogen concentrations decreased and increased with time respectively, while the nitrite nitrogen level increased first and then reduced. The relationship between the COD or ammonia nitrogen loading and its removal rate was examined, and the removal of COD, ammonia nitrogen and total nitrogen could exceed 95%, 90% and 80% respectively. The fact that nitrogen could be removed more completely under constant aeration (aerobic condition) of the SBBR operation mode is very interesting and could be explained in several respects.

碱激活PMS氧化法协同SBBR深度处理焦化废水研究

采用碱激活过一硫酸盐(PMS)氧化法协同序批式生物膜反应器(SBBR)工艺深度处理焦化废水,研究当以NaOH作为激活剂时,pH、PMS浓度和温度对碱/PMS体系去除焦化废水生化出水COD和色度的影响,之后考察SBBR工艺处理碱/PMS体系出水的效果。研究结果表明,碱/PMS体系深度处理焦化废水的最佳条件为温度25℃、pH=10、PMS投加浓度7 mmol/L、反应时间4 h,在此条件下色度和COD的去除率分别为96.1%和45.9%。电子顺磁共振实验表明碱/PMS体系存在^(1)O_(2)、O_(2)•-、∙OH和SO_(4)•-等活性氧物种。废水经碱/PMS体系处理后可生化性提高,之后经SBBR工艺进一步处理后出水COD<60 mg/L。总体而言,碱激活PMS氧化法协同SBBR工艺对COD的平均去除率达66.7%。焦化废水生化出水处理前后的三维荧光光谱分析表明,碱/PMS体系协同SBBR工艺能去除焦化废水生化出水中的芳香蛋白类物质和类腐殖酸物质。

成批大面积烧伤患者的组织救治效果分析

目的 分析成批大面积烧伤患者的组织救治效果。方法 19批(79例)烧伤面积>30%的大面积烧伤患者,均接受补液等药物治疗、气管切开、创面治疗以及其他治疗。记录治疗结果,并比较治疗前后患者的生长因子[血管内皮生长因子(VEGF)、S100钙结合蛋白A9(S100A9)、碱性成纤维细胞生长因子(bFGF)]水平、疼痛因子[P物质(SP)、前列腺素E2(PGE2)、环氧化酶2(COX-2)]水平。结果 79例患者治愈69例,死亡10例,其中4例死于创面感染,2例死于重度吸入性损伤,1例死于后期气管切开的无名动脉出血,1例死于肾衰竭,1例死于继发性肺炎,1例死于导管败血症。治疗后,患者的VEGF(265.73±18.49)μg/L、S100A9(176.49±10.18)μg/L、bFGF(274.85±18.63)μg/L均高于治疗前的(110.54±7.63)、(80.53±3.12)、(101.52±7.24)μg/L,差异有统计学意义(P<0.05)。治疗后,患者的SP、PGE2、COX-2分别为(46.53±5.11)ng/ml、(124.39±10.67)pg/ml、(53.47±3.42)ng/ml,均低于治疗前的(75.29±10.24)ng/ml、(238.74±20.15)pg/ml、(126.79±10.82)ng/ml,差异有统计学意义(t=22.337、44.576、57.429,P=0.000、0.000、0.000<0.05)。结论 针对成批大面积烧伤患者实施组织救治的效果显著,有利于减轻疼痛程度,调节生长因子水平,临床可进一步推广应用。

城市污水处理不同序批式活性污泥法的工艺特点和功能差异分析

城市污水处理是保障城市环境卫生和健康的重要环节,而序批式活性污泥法作为一种常用的污水处理技术,具有灵活、高效、适应性强的特点。然而,不同的序批式活性污泥法在工艺特点、功能差异、优缺点以及应用场景上存在差异。因此,对这些技术进行深入研究和比较,对于选择适合的污水处理工艺具有重要意义。

连续流反应器中好氧颗粒污泥快速培养研究进展

好氧颗粒污泥(aerobic granular sludge,AGS)是目前最有前景的污水生物处理技术之一,采用连续流反应器(continuous flow reactor,CFR)进行AGS快速培养的技术近年来受到广泛关注。文中通过综述间歇式反应器(sequencing batch reactor,SBR)工艺实现快速颗粒化的调控方法、CFR强化颗粒化及优化控制,总结了目前SBR工艺实现快速颗粒化的主要措施,以及采用基于SBR颗粒化的原理在CFR中实现快速颗粒化的可行方案,包括选择压优化、饱食/饥饿(feast/famine)条件以及晶核策略(crystal nucleus)等。最后对CFR工艺实现快速颗粒化的应用前景进行了展望,并提出探究SBR中强化颗粒化的策略,将有望在未来更加深入地研究AGS在CFR中的形成机理。

Stream Monitoring and Preliminary Co-Treatment of Acid Mine Drainage and Municipal Wastewater along Dunkard Creek Area

This study investigated coal-mine drainage(AMD)and municipal wastewater(MWW)contaminant concentrations and conducted the combined treatment in phases I and II:phase I,evaluating the effects of mixing the two based on the extent of acid neutralization and metals removal;phase II:conducting anaerobic batch reactor treatment of AMD and MWW under varying COD/sulfate ratios(0.04-5.0).In phase I,acid mine drainage water quality conditions are as follows:pH 4.5,acidity 467.5 mg/L as CaCO3,alkalinity 96.0 mg/L as CaCO3,Cl-11.8 mg/L,SO42-1722 mg/L,TDS 2757.5 mg/L,TSS 9.8 mg/L,BOD 14.7 mg/L,Fe 138.1 mg/L,Mg 110.8 mg/L.Mn 7.5 mg/L,Al 8.1 mg/L,Na 114.2 mg/L,and Ca 233.5 mg/L.Results of the mixing experiments indicated significant removal of selected metals(Fe 85~98%,Mg 0~65%,Mn 63~89%,Al 98~99%,Na 0~30%),acidity(77~95%)from the mine water and pH was raised to above 6.3.The Phase II results suggested under the wide range of COD/sulfate ratios,COD and sulfate removal varied from 37.4%-100%and 0%-93.5%respectively.During biological treatment,alkalinity was generated which leads to pH increase to around 7.6-8.5.The results suggested feasibility of the proposed technology for co-treatment of AMD and MWW.A conceptual design of co-treatment system which is expected to remove a matrix of pollutants has been provided to utilize all the locally available water resources to achieve the optimum treatment efficiency.The technology also offers an opportunity to significantly reduce capital and operating costs compared to the existing treatment methodologies used.Featured Application:In this study,we have measured the concentrations of contaminants in acid mine drainage(AMD)and municipal wastewater(MWW)and conducted the combined treatment in phases I and II.This is significant because in previous years there was a massive fish kill that is linked to the high total dissolved solids(TDS)and salinity content in the water.With the current proposed combined treatment technology,it shows high potential in reducing TDS and salinity content in the combined wastewater which will prevent similar accident(Dunkard creek fish kill in 2019)happening again.

Research Development and Application of Nitrogen and Phosphorus Removal in Sequencing Batch Biofilm Reactor

Frequent variations of the wastewater quality and quantity and other uncertain factors are the challenges faced by many wastewater treatment plants during the operation. Sequencing batch biofilm reactor（ SBBR） process provides a new idea for an effective solution to this problem. This paper introduces the basic processes and characteristics of the sequencing batch biofilm reactor（ SBBR） process,and summarizes the research status of this process in wastewater treatment. Factors affecting the nitrogen and phosphorus removal effect of the SBBR process are also analyzed.

Factors affecting biological denitrifying dephosphatation in anaerobic/anoxic/aerobic sequencing batch reactor

This study was conducted to verify and discuss the denitrifying dephosphatation under different levels of nitrate concentration and retention time of anoxic/aerobic process in a Sequencing Batch Reactor (SBR). The results of tests demonstrated that there were two kinds of phosphorus-accumulating organisms (PAOs) in the biological excess phosphorus removal (BEPR) system. One was non-DNPAOs that could only use oxygen as terminal electron acceptors, the other was denitrifying PAOs (DNPAOs) that could use both nitrate and oxygen as terminal electron acceptors. Phosphorus uptake efficiency could be attained under anoxic period ranging from 28.7%-96.7% in an anaerobic/anoxic/aerobic system. Experimental results showed that nitrate concentration and retention time of anoxic/aerobic process were the key factors affecting the course of denitrifying dephosphatation.

Characterization of the start-up period of single-step autotrophic nitrogen removal in a sequencing batch reactor

The characteristics of the start-up period of single-step autotrophic nitrogen removal process were investigated. The autotrophic nitrogen removal process used a sequencing batch reactor to treat wastewater of medium to low ammonia-nitrogen concentration, with dissolved oxygen (DO), hydraulic retention time (HRT) and temperature controlled. The experimental conditions were temperature at (30±2) °C, ammonia concentration of (60 to 120) mg/L, DO of (0.8 to 1.0) mg/L, pH from 7.8 to 8.5 and HRT of 24 h. The rates of nitrification and nitrogen removal turn out to be 77% and 40%, respectively, after a start up period going through three stages divided according to nitrite accumulation: sludge domestication, nitrifying bacteria selection and sludge adaptation. It is demonstrated that dissolved oxygen is critical to nitrite accumulation and elastic YJZH soft compound packing is superior to polyhedral hollow balls in helping the bacteria adhere to the membrane.

棉织物酶法轧堆精练工艺及处理效果

测试了精练酶BioPrep^(■)Fusion和碱性果胶酶的酶学特性,并对棉织物进行冷轧堆精练处理。通过测试毛细效应、润湿时间和果胶去除率,比较了不同的果胶酶冷堆精练工艺对棉织物处理效果的影响。再将不同果胶酶冷堆精练处理后的织物进行轧蒸氧漂与染色,并与碱法冷堆精练-轧蒸氧漂前处理效果对比。结果表明,精练酶BioPrep^(■)Fusion精练效果较好,当酶质量浓度为6 g/L时,冷堆精练后和轧蒸氧漂后的果胶去除率分别为85.7%和93.3%,毛细效应分别为10.9 cm和11.5 cm,润湿时间均小于5 s。

基于Arcpy的长顺县国储林实施方案小班设计图自动出图方法优化

林业制图的自动化是林业信息化进程中不可缺少的一部分,Arcpy作为基于Python语言开发的ArcGIS内置站点包,集成了ArcGIS大部分功能,为自动化制图提供了许多途径。利用Arcpy设计出图代码,对出图过程进行优化,自动检测出图要素与小班设计表是否重叠、计算图框平移距离等,在保证出图要素尽量居中的条件下实现与小班设计表的不重叠,为林业制图的美观化、自动化提供了一条新的途径。

浅谈多品种小批量产品热处理的节能减排

针对多品种小批量产品的热处理,以某船舶配套企业为例,从建立设计选材规范、设计要求标准化、热处理设备选型规范化、冷热工艺协调规范化、热处理工艺创新及通用化、组批生产管理规范的建立、热处理质量控制规范的建立等方面阐述了热处理节能减排的措施,这些措施经过实践检验,绩效显著,期望给大家以有益的启示。

外源微塑料输入对SBR系统污水处理性能的影响

采用序批式反应器(SBR)处理模拟生活污水,考察了外源微塑料聚酰胺(PA)和聚氯乙烯(PVC)输入对SBR系统污水处理效果及污泥性能的影响。结果表明,在30个运行周期内持续输入10 mg/L的PA对污水处理效果的影响较小,但当PA输入量增加到50~100 mg/L时,COD、NH^(+)_(4)-N和TP去除率均值分别比无外源PA输入时下降了2.1%~4.5%,8.3%~13.0%和11.8%~21.4%。当PVC输入量为100 mg/L时,对污水处理效果的影响最大,COD、NH^(+)_(4)-N和TP去除率均值分别比无外源PVC输入时降低了14.3%、23.2%、31.6%,去除速率也表现出明显的下降趋势。从污泥指标变化情况来看,外源PA、PVC输入会导致污泥量不同程度的减少,功能菌群代谢能力下降,进而导致污染物去除效果变差。因此,PA、PVC的持续输入将破坏SBR系统的稳定运行,对污水中的微塑料进行预处理对保持该系统的高效净水性能十分重要。

不同COD/N对主流同步短程硝化反硝化的影响

为了解决农村生活污水生物脱氮过程中碳源不足的问题,利用混合悬浮污泥和生物膜的多循环序批式反应器(Sequencing Batch Reactor,SBR)建立了同步短程硝化反硝化工艺,并详细分析了COD/N比例对该工艺的影响。当COD/N比例为4∶1时,总氮去除率和亚硝化率分别达到85.0%和95.6%;当COD/N比例为2∶1时,总氮去除率和亚硝化率分别为76.1%和83.8%;当COD/N比例降至1∶1时,总氮去除率降至31.0%,而亚硝化率仅1.2%,说明COD/N比例对同步短程硝化反硝化影响明显。当碳源充足时,NO^(-)_(2)-N可在缺氧段被全部去除,导致亚硝酸氮氧化菌(Nitrite Oxidizing Bacteria,NOB)的可利用底物(NO-2-N)远远低于氨氧化菌(Ammonium Oxidizing Bacteria,AOB)的可利用底物(NH^(+)_(4)-N),且生物膜内缺氧反硝化菌也能在好氧段进行反硝化,进一步减少了NOB的可利用底物。加上短污泥龄控制,悬浮NOB被持续冲刷排出。因此,多循环SBR内NOB抑制的核心点是高COD/N情况下反硝化菌与NOB竞争NO-2-N,通过强化反硝化抑制NOB的策略可在工程应用中予以借鉴。

华龙一号批量化示范工程固体废物处理系统工艺改进分析

华龙一号技术承载着中国核电技术向外出口的重任,其设计在保障安全可靠的同时,还需保证其经济性和先进性,废物最小化是华龙一号第三代先进堆型持续改进的目标。本文从华龙批量化示范工程固体废物系统(ZST系统)废物处理工艺系统改进入手对ZST系统功能进行了详细阐述,通过将华龙一号参考机组与华龙一号批量化示范工程所产生的工艺废物类型、工艺废物产生量、工艺废物处理工艺进行了全面对比分析与探讨,在结合同行电站和国外电厂放射性废物管理经验反馈的基础上,对废物包预期产生量进行了深入论证,分析结果表明华龙一号批量化示范工程较华龙一号参考机组在废物产生量上会有较大改观,在废物包性能符合国家相关标准要求的前提下,单台机组每年废物包产生量满足不超过50m3/a的要求,改进方案可行。