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啤酒废水处理再利用
重庆大学外文翻译题目:啤酒废水处理再利用n指导教师评定成绩(五级制):指导教师签字:附件C:译文啤酒废水处理再利用1,介绍尽管整个一年排放了大量的废水,酿造业的一个重要组成部分,任何国家的经济,事实上,啤酒是五十大多数消费的饮料在世界茶,碳酸盐,牛奶和咖啡,啤酒酿造涉及2个主要步骤,即,酿造和包装的完成产品。(例如,从酵母糖化糟,剩余,等)所产生的这些步骤是负责污染混合在一起时,废水此外,清洗罐,瓶,机器,产生高量水,据估计生产1升啤酒,3–10升废水的产生生产和特殊的丙型水使用。换句话说,大量水消耗在啤酒生产过程。同样,由于使用大量的水,啤酒工业全年排放大量高污染的废水。还必须指出废水个别工艺步骤变量。例如,洗瓶结果在一个大型的废水量,但它只包含一小部分的总有机物排放从酿酒工艺,另一方面,从废水发酵和fi滤波是高有机物/生化需氧量(生化需氧量),但一般量低,约占总数的3%,但97%的生化需氧量的废水量。啤酒厂废水排放可能在几个方面,包括以下内容:(1)直接进入航道(海洋,河流,溪流,美丽的),(2)直接进入市政下水道系统,(3)到水道或市政下水道系统后的废水进行了一些预处理,(4)到酿酒厂的污水处理厂处理。治疗(或治疗)啤酒废水进入水体可构成潜在的或严重的污染问题,水自废水含有有机化合物需要氧降解。例如,如果水的有机质含量高值fl流入河流,细菌在河流会氧化有机物消耗水中氧气的速度比氧气溶解在空气中的河。此外,规章变得越来越严格的成本和水,呼吁水循环是目前获得了很多动力。有许多文件,如审查fillaudeau等人。,处理好几个方面的啤酒废水处理。然而,审查本文献表明,只有在多年后的信息成为可在水回用处理。必须指出,然而,,污水回用是不常见的这种类型的该行业由于公众的看法和可能的产品质量恶化的问题。然而,未来再利用啤酒废水似乎是不可避免的,随着水资源短缺问题已成为一个严重的全球性环境问题。尤其是非常关键的在大多数发展中国家,如撒哈拉以南地区,旱灾是永久的,因此每一滴水都必须精确地保守。在本文中,潜在的机会,可用于处理啤酒废水再利用的应用进行了综述,即:(一)主要用于生产啤酒,和(二)二次水不接触到啤酒;e.g.utilities冷却,水用于包装过程和一般的清洁水。一旦技术的提高和观念已经改变,关于使用再生水,水比啤酒被认为可以减少的比例约为1:2。相关的挑战,如相关啤酒废水回用(或循环)进行了探讨。治疗,恢复和应用各种啤酒厂副产品(例如,谷物,花啤酒花,剩余污泥的酵母,硅藻土,残渣和废物标签)已被广泛记载的其他地方,因此不在本文探讨。因此,本文的组织如下:一个背景的立法和环境管理系统提出fi第一,之后连续的前后处理啤酒废水的方法。挑战和未来前景被列入讨论走向尽头。总结,然后提供给管理论文.n2.立法和环境管理系统像任何其他行业一样,酿造业受到广泛的政府规章。一些规定涉及的生产,分配,标签,广告,定价和贸易惯例,信用,容器的特点,和酒精含量要求。政府机构也征收各种税金许可费和其他类似的指控,并可能需要债券以确保遵守适用的法律和法规。此外,环境管理问题日益感兴趣的东西。有一个需要了解的重要的环境影响的社区,然后考虑相关的优点和缺点的各种层次的环境管理。这意味着,酿酒业也必须遵守许多环境保护法。事实上,啤酒行业已显示出越来越多的环保意识和可持续生产过程的需要。此外,大多数国家的政府在这些行业的经营已签署和理性fi了京都议定书旨在减少温室气体的排放量。通过环境管理系统(特快专递)等,(1)14001,(2)生态管理和审计计划(金),和(3)国际安全等级制度(ISR),啤酒应该能够主动管理对环境的影响。实际上,环境管理体系应该帮助酿酒重点放在有效和英法fi有效管理对当前和未来的环境影响。国际金融公司(国际金融公司)也有环境,健康和安全(安全)的指导方针的酿酒厂。3.传统方法的预处理啤酒废水通常具有较高的化学需氧量(化学需氧量)从所有的有机成分(糖,可溶性淀粉,酒精,挥发性脂肪酸,等等)。它通常有温度范围从25℃到38℃°°,但偶尔达到很高的温度。PH值范围之间的2和12,在fl严重的数量和类型的化学品,用于清洗和消毒(例如,烧碱,磷酸,硝酸,等。)。化学消毒,包括氯化合物,以确保表面是免费的任何有害的微生物酿造行业和大众消费的啤酒。氮磷水平主要取决于处理和原材料的数量目前在英法fl酵母厂。是一个例子,理化特性,啤酒废水,联合印度酒厂。事实上,啤酒废水的特点是有很大差异的参数中提到的。因此,需要一定程度的最大型啤酒厂废水预处理。如啤酒不排放到市政下水道,然后初级和二级处理的英法fl的要求。然而,如果酒厂是允许的排入市政下水道,预处理可能需要符合市政规章和/或减少负载的市政污水处理厂。在某些情况下,污水排放费对英法fl的体积,并在暂停和有机负荷,由市政府鼓励啤酒厂安装自己的处理设施。预处理的目的是改变了物理,化学,和/或生物特性的水,从而提高性能的上游的过程。因此,预处理是通过物理,化学,生物,或结合所有这些方法,单元操作包括在每个类别中,并详细示意图代表性的传统的废水处理过程中可以找到斯佩尔曼的标准手册废水算子。总结了通用的优点和缺点的各种污水处理过程如图所示,在文献。这些特征(表3)一般涉及建筑成本和易于操作。通常,复杂性和成本的污水处理技术的提高与质量的英法fl的产生。事实上,水管理和废物处理在啤酒行业被视为重要fi不能成本因素和重要方面的运作一个啤酒厂。3.1物理方法n在复位治疗方法使用的物理单元操作,其中的物理力量应用到去除污染物。物理方法去除粗固体物质,而非溶解性污染物。它可能是被动的过程,如沉积允许暂停污染物停留或fl燕麦顶自然一般,这些方法。取得了一些成功;最常造成不完全去除污染物和/或分离,例如,沉淀已被认为是不能令人满意,即使增加混凝剂和其他添加剂。3.2化学方法不同的化学物质可以被添加到啤酒废水改变水化学。化学预处理可能涉及PH值调整或凝血和fl遮掩。酸性或碱性废水影响污水处理和环境。值低表明增加酸度而高值表明增加碱度。酸碱废水需要保持在6和9保护生物。废钴2可用于中和碱废水督察系统和洗瓶机。废物二氧化碳也可以被用来作为一种廉价的酸化剂降低PH值碱性废水在厌氧反应器,从而取代传统使用的酸。中和4和2盐酸酸通常不推荐,因为他们的腐蚀性和硫酸盐和氯化物排放限制,这可能增加成本,有效的治疗操作。凝血和fl遮掩是物理化学过程通常用于消除胶体材料或颜色的水和废水。在水和废水处理,混凝意味着步骤,粒子是不稳定的混凝剂,这可能包括形成小总量的布朗运动(异向凝聚)。另一方面,随后的过程其中较大的总量(业主立案法团)是由剪力的作用,是当时称为fl遮掩。后有小颗粒形成较大的总量,胶体材料可以更容易地去除的物理分离过程,如沉淀。3.3生物方法废水生物处理过程中发挥中心作用的社会管理他们的废水。它是基于活动的范围广泛的微生物,使有机污染物降解的废水。事实上,啤酒废水有化学(非常高有机物含量)和微生物污染物一般是采用生物方法。因此,在啤酒废水进行了物理和化学预处理,然后进行生物处理的废水。比较物理或化学方法,生物的方法有三个优点:(1)治疗技术成熟,(2)高效制fi鳕鱼和生化需氧量的去除,范围从80到90%,和(3)投资成本低。然而,尽管生物处理过程是特别有效的废水处理,他们需要一个高能量输入。废水生物处理可以是有氧(空气/氧气供应)和厌氧(没有氧气)。有氧淹水过程图形显示。这些进程进行了讨论更多的细节在随后的章节。一般来说,有氧治疗已成功用于处理啤酒废水厌氧系统,最近已成为一个具有吸引力的选择。提出了一种一般比较好氧和厌氧生物处理系统的活性污泥。4.啤酒废水处理回用排出的废水生物处理过程可以进一步处理。在这部分的各种方法,可用于处理啤酒废水再利用进行了探索。要注意的是,然而,回收再生水为酿造水被认为是不恰当的和需要的饮用水标准的遵守。显示最重要的标准进行清洗,冷却和饮用水。在参数中,最重要的参数,循环水或需要测量是鳕鱼。鳕鱼是一个衡量的氧气当量的有机质含量的样本,这是容易氧化的强氧化剂。鳕鱼是一个合适的指数显示的数额在水中有机物。化学需氧量值的废水主要是生物降解和生物降解的有机组成部分,虽然无机化合物可明显fi不能在某些情况下。然而,一般来说,啤酒英法fluents是易降解的生化需氧量/化学需氧量比的范围为0.6–n0.7。有机成分的啤酒厂(英法fl表示阿斯科德)组成的糖,可溶性淀粉,酒精,挥发性脂肪酸,等等。4.1利用碳纳米管自重新发现的碳纳米管(碳纳米管)由1991饭,几个世界各地的研究人员在所有学科已经着手促进研究利用各种独特性能的这些材料。碳纳米管组成的蜂窝结构的石墨片为气缸直径为几纳米,但许多微米或厘米长度。许多方法和碳源生长碳纳米管一直积极推行在过去几年中,而这些概述了若干审查文件。通常有2种形式的碳纳米管根据一些卷起来的石墨层,形成管,即,单壁碳纳米管(单壁碳纳米管)和多壁碳纳米管(多壁碳纳米管)。该模型表征多壁碳纳米管和单壁碳纳米管中显示。独特性能的碳纳米管产生特殊的原子和电子结构。由于其独特的结构,机械,和电子性能,碳纳米管具有很大的潜力,在众多的应用前景,如化学传感器,fi场发射材料和催化剂载体。一些重要的应用碳纳米管对水处理讨论如下。4.2碳特征一个水处理厂有重大的影响fl特征性质的最终产品。即使在进入的过程是从一个城市饮用水水源,水中可能含有残余的味道,气味,消毒副产物,与自由和结合氯。分子与碳–硫债券往往气味和味道不好,但这些往往是优先吸附在碳。同样是真实的分子与芳香环。碳的得氯化能力从能力作为还原剂的反应与强氧化剂次氯酸钠和二氧化氯等。治疗单宁酸和气味去除工艺应用在酿造碳吸附使用。碳也用到消除色彩从麦芽用于啤酒和其他明确麦芽饮料。几个粒状和粉状产品还能用于这类应用。活性炭是一种有效的治疗,是保证水污染物,滋味,无异味。5.讨论和合成废水表现本节提供了一个讨论和综合审查fi表现的文章。本文包括一个比较和可能的一体化的过程和技术。简而言之,讨论主要涉及下列基本问题:(一)如何互相比较的过程和技术?(二)他们可以相互融合,如果是这样,还有什么潜在的挑战和利益fi禁忌?5.1比较的过程和技术这次审查强调需要处理啤酒废水,看着各种方法,可用于安全和有效地处理啤酒废水的再利用。此外,一些相关的挑战与这些方法进行了讨论。应该指出,强调此处处理啤酒废水的英法fl是昂贵的和相对复杂的活动;特别是与需要符合政府法规和环保。传统的分离方法如凝血/fl遮掩,离心,和重力分离出缺点包括不完整的去除。这些方法通常与低效率fin分离效率,运行成本高,规模大的设置,以及产生二次污染物。它还注意到生物处理是广泛应用的一种预处理方法。一般来说,有氧治疗已用于处理啤酒废水和最近,厌氧系统已成为一个具有吸引力的选择,除其他优势,因为他们的高化学需氧量的去除。尽管这些生物方法已广泛应用於治疗的特点是高有机物含量的啤酒废水,进一步的治疗是水回用。然而,这项审查表明了一些可喜的成果与淬火等离子,膜生物反应器,电化学方法,和微生物燃料电池。这些方法有很大的潜力可用于处理啤酒废水再利用和需要进一步调查,相对于不同的挑战和机会参与。例如,啤酒废水中可能是一个很好的电力来源的微型燃料电池发电由于其性质的高碳水化合物低–砂体铵氮浓度。作者还指出,最近的进展表明,许多最近的问题解决水质神往科技可以解决或大大改善使用碳纳米管作为吸附剂。因此,预计啤酒厂的行业也将奈fi从这些发现。然而,所需的知识,为大规模的设计和应用的过程中讨论这一审查也许是仍然缺乏。它进一步建议进行一些研究,建立估计资本成本的这些可喜的过程。另一方面,应用膜废水(例如,氮和反渗透)饮用水处理和废水回用,虽然确立,经历了加速发展的十年与改善膜质量和减少膜的成本。一个非常重要的发展趋势废水膜水处理是整合不同的预处理策略来提高他们的绩效。反渗透,特别是,已被证明是一种有效的有效和成本有效的方法处理啤酒废水的回用。显示了一个简要的一些研究进行了啤酒废水的化学需氧量减少,显示,和英法的fl是否适合作为小学或中学的基础上列出的体格生长。要注意的是,然而,这些研究不同的实验设计。5.2一体化的过程和技术。它可以被看到,不经常他的方法(除了反渗透)可以单独使用在啤酒废水处理中的应用具有良好的经济性和高的能量效率的英法fi耦合这些进程一起为两年或三阶段的过程中会更合适。随后,不同的工艺组合的建议和讨论。在可再生能源的需求在我们的社会是不断增加。因此,在微型燃料电池的建议是fi第一预处理阶段的每一个综合过程,特别技术。微型燃料电池的操作和功能优势的技术目前用于发电的有机物质。首先,直接转换为电能使基板高转换效率的英法fi,不同的生物过程反应器的代谢产物(例如,3)要用于锅炉产生能源。其次,微型燃料电池经营英法fi均在室温下。第三,一个不需要处理因为场外气体微型燃料电池中有丰富的二氧化碳,通常没有有用能源的内容。第四,微型燃料电池不需要能量输入曝气提供阴极是被动曝气。第五,微型燃料电池具有潜在的广泛应用地点缺乏电力基础设施和还可以与不同的燃料来满足能源需求。高效果fi效率也可以减少负载耦合阶段。使用其他技术的fi第一阶段的综合过程,也不提供任何可预见的利益指标。n电化学方法可以适合耦合在后一阶段的综合过程。消毒剂(通常称为消毒剂)这是目前在啤酒废水含有氯化合物。这些化合物产生的氯和氯电解过程中,此后,生成次氯酸的氧化有机化合物。氯是一种最广泛使用的消毒剂。这是非常适用的和非常有效的失活的病原微生物。因此,如果加上电化学方法在后期可以作为一个有机氧化和消毒阶段。血浆的方法非常有效,这个过程是昂贵的,由于高能源需求的气体,和能源成本的来源,如激光。因此,如果加上其他的方法,这个过程可以是非常昂贵的。碳纳米管表现出显著的吸附能力。结合碳纳米管与用友将导致大量的有机物去除。然而,碳纳米管的加入将迅速增加跨膜压力迅速由于形成碳纳米管蛋糕上的膜表面。在这种情况下,碳纳米管可能需要有足够大的直径,减少跨膜压力的影响。对膜生物反应器一般,防污减灾可能会做的耦合凝血和fl遮掩的过程。6.总结水是一种常见的元素在生活的所有的人和社会。水是基础,有时,许多伟大的文明的毁灭。今天,水仍然是至关重要的维持生命(人类和动物),农业,经济和工业活动,帮助社会发展。不到一个世纪以前,人们普遍认为,有足够的淡水资源在世界的每个人。然而今天,增加使用的淡水用于工业,农业,和国内使用造成严重水资源短缺在世界一些地区,特别是发展中国家。这些短缺刺激或恶化的国际会议fl或称水,已加入油作为主要商品引发战争。在场的污染物在水人类活动也加剧了情况。另一方面,废水回收和再利用已成为一个重要的选择,因为工业化和城市化加速了环境污染,使有限的资源用于给水。当妥善处理和回收,废水可以替代水源,可奈fi是有效减少需求的淡水。它可以得出这样的结论:的确,随着世界人口的增长和工业活动,加上严格的环保要求,水的成本增加。因此,要求水回用在啤酒行业预计将增加,以前所未有的速度。因此,越来越需要过程能够实现有效的fi有效处理在极端操作条件,同时优化运营成本可以预期的未来。从获得的信息,这项审查表明,以去除杂质有效地fi,整合不同的处理建议。免责声明:本文研究的内容是废水等作者的看法,谁负责的事实和数据的准确性提出的,不一定是fl等的fi社会观点或政策的任何机构或机构。本文并不构成一种,废水阳离子,也不是设计,投标,承包,施工,或许可证的目的。n译文原文ThetreatmentofbrewerywastewaterforreuseGeoffreyS.Simate,JohnCluett,SunnyE.lyuke,EvansT.Musapatika,SehliseloNdlovu,LubindaF.Walubita,AllexE.Alvarez1.IntroductionDespitedischarginglargevolumesofhighlypollutingeffuents,roughouttheyear,thebrewingindustryconstituteanimportanteconomicsegmentofanycountry.Infact,beeristhefifthmostconsumedbeverageintheworldbehindtea,carbonates,milkandcoffee.Beerbrewinginvolvestwomainsteps,i.e.,brewingandpackagingofthefinishedproduct.Theby-products(e.g.,spentgrainsfrommashing,yeastsurplus,etc)generatedfromthesestepsareresponsibleforpollutionwhenmixedwitheffluents.Inaddition,cleaningoftanks,bottles,machines,andfloorsproduceshighquantitiesofpollutedwater.Itisestimatedthatfortheproductionof1Lofbeer,3–10Lofwasteeffluentisgenerateddependingontheproductionandspecificwaterusage.Inotherwords,verylargequantitiesofwaterareconsumedduringthebeerbrewingprocess.Similarlyandbecauseofvoluminouswaterusage,thebreweryindustrydischargeslargevolumesofhighlypollutingeffluentsthroughouttheyear.Itmustalsobenotedthateffluentsfromindividualprocessstepsarevariable.Forexample,bottlewashingresultsinalargewastewatervolume,butitcontainsonlyaminorpartofthetotalorganicsdischargedfromthebreweryprocesses.Ontheotherhand,effluentsfromfermentationandfilteringarehighinorganics/biochemicaloxygendemand(BOD),butgenerallylowinvolume,accountingforabout3%ofthetotalwastewatervolumebut97%oftheBOD.Wastewaterfromabreweryplantmaybedischargedinseveralwaysincludingthefollowing:(1)directlyintoawaterway(oceans,rivers,streams,orlakes),(2)directlyintoamunicipalsewersystem,(3)intothewaterwayormunicipalsewersystemafterthewastewaterhasundergonesomepretreatment,and(4)intothebrewery'sownwastewatertreatmentplant.Thedisposalofuntreated(orpartiallytreated)brewerywastewaterintowaterbodiescanconstitutepotentialorseverepollutionproblemstothewaterbodiessincetheeffluentscontainorganiccompoundsthatrequireoxygenfordegradation.Forexample,ifwaterofhighorganicmattercontentvalueflowsintoariver,thebacteriaintheriverwilloxidizetheorganicmatterconsumingoxygenfromthewaterfasterthantheoxygendissolvesbackintheriverfromtheair.Furthermore,asregulationsbecomemoreandmorestringentandthecostofwaterincreases,thecallforwaterrecyclingiscurrentlygainingalotofmomentum.Therearemanypapers,suchasthosereviewedbyFillaudeauetal.,dealingwithseveralaspectsofbrewerywastewatertreatment.However,areviewofthisliteratureshowsthatonlyinlateryearshasinformationbecomeavailableonwatertreatmentforreuse.Itmustbenoted,however,thatwastewaterreuseisnotcommoninthistypeoftheindustryduetopublicnperceptionandthepossibleproductqualitydeteriorationproblems.However,thefuturereuseofbrewerywastewaterseemstobeunavoidable,astheissueofwatershortagehasbecomeaseriousglobalandenvironmentalproblem.Thisisparticularlyverycriticalinmostdevelopingcountriessuchasthesub-Saharanregionwheredroughtsareperpetual,thuseverydropofwatermustbepreciouslyconserved.Inthispaper,thepotentialopportunitiesthatmaybeavailablefortreatingbrewerywastewaterforreuseintwoapplicationsarereviewed,namely:(a)primarywaterusedintheproductionofbeer,and(b)secondarywaterthatdoesnotcomeincontactwithbeer;e.g.utilitiescooling,waterusedinthepackagingprocessandgeneralcleaningwater.Oncetechnologyimprovesandtheperceptionshavechangedregardingtheuseofrecycledwater,beertowaterratiosisperceivedmaybereducedtotheratioofabout1:2.Pertinentchallengesasrelatdtobrewerywastewaterreuse(orrecycling)arealsodiscussedinthepaper.Thetreatment,recoveryandapplicationsofvariousbrewerybyproducts(e.g.,spentgrains,spenthops,surplusyeast,kieselghursludge,trubandwastelabels)havebeenextensivelyDocumentedelsewhere,thusarenotdiscussedinthispaper.Accordingly,thepaperisorganizedasfollows:abackgroundofthelegislationandenvironmentalmanagementsystemsispresentedfirst,followedconsecutivelybybrewerywastewaterpre-andtreatment-methods.Challengesandfutureprospectsareincludedinthediscussiontowardstheend.Asummaryisthenprovidedtoconcludethepaper.2.LegislationandenvironmentalmanagementsystemsLikeanyotherindustry,thebrewingindustryissubjecttoextensivegovernmentregulations.Someoftheregulationsimposedinvolveproduction,distribution,labeling,advertising,tradeandpricingpractices,credit,containercharacteristics,andalcoholiccontentrequirements.Governmentalentitiesalsolevyvarioustaxes,licensefeesandothersimilarchargesandmayrequirebondstoensurecompliancewithapplicablelawsandregulations.Furthermore,themanagementofenvironmentalissuesisofgrowinginterestnowadays.Thereisaneedtounderstandtheimportantenvironmentalimpactsonthecommunityandthenconsidertheadvantagesanddisadvantagesassociatedwithvariouslevelsofenvironmentalmanagement.Thismeansthatthebrewingindustrymustalsocomplywithnumerousenvironmentalprotectionlaws.Infact,thebrewingindustryhasshownincreasingawarenessforenvironmentalprotectionandtheneedofsustainableproductionprocesses.Furthermore,mostnationalgovernmentswheretheseindustriesoperatehavesignedandratifiedtheKyotoProtocolaimedatreducinggreenhousegasemissions.Throughenvironmentalmanagementsystems(EMS)suchas,(1)ISO14001,(2)Eco-ManagementandAuditScheme(EMAS),and(3)InternationalSafetyRatingSystem(ISRS),breweriesshouldbeabletoproactivelymanagetheirimpactsontheenvironment.Infact,EMSshouldhelpbreweriesfocusoneffectiveandefficientmanagementofbothcurrentandfutureenvironmentalimpacts.TheInternationalFinanceCorporation(IFC)alsohasenvironmental,healthandsafety(EHS)guidelinesforbreweries.3.ConventionalmethodsofpretreatingbrewerywastewaternBrewerywastewatertypicallyhasahighchemicaloxygendemand(COD)fromalltheorganiccomponents(sugars,solublestarch,ethanol,volatilefattyacids,etc).Itusuallyhastemperaturesrangingfrom25°Cto38°C,butoccasionallyreachingmuchhighertemperatures.ThepHlevelscanrangebetween2and12andareinfluencedbytheamountandtypeofchemicalsusedincleaningandsanitizing(e.g.,causticsoda,phosphoricacid,nitricacid,etc.).Sanitizingchemicalswhichincludechlorinecompoundsensurethatthesurfacesarefreeofanymicroorganismsharmfultothebrewingindustryandthepublicconsumingthebeer.Nitrogenandphosphoruslevelsaremainlydependentonthehandlingofrawmaterialandtheamountofyeastpresentintheeffluent.isanexampleofthephysicochemicalcharacteristicsofbrewerywastewaterfromtheUnitedBreweriesinIndia.Infact,thebrewerywastewaterischaracterizedbylargevariationsintheparametersmentionedin.Asaresult,mostlargebreweriesrequiresomedegreeofwastewaterpretreatment.Incaseswherethebrewerydoesnotdischargetothemunicipalsewer,thenprimaryandsecondarytreatmentoftheeffluentisrequired.However,ifthebreweryispermittedtodischargeintoamunicipalsewer,pretreatmentmayberequiredtomeetmunicipalbylawsand/ortolessentheloadonthemunicipaltreatmentplant.Insomecases,sewerdischargefeesimposedoneffluentvolume,andonthesuspendedandorganicloads,bythemunicipalitymayencouragethebrewerytoinstallitsowntreatmentfacility.Pretreatmentismeanttoalterthephysical,chemical,and/orbiologicalpropertiesoffeedwater,thusimprovingtheperformanceofupstreamprocesses.Therefore,pretreatmentisdonebyphysical,chemical,orbiologicalmethods,orbyacombinationofallthesemethods.liststheunitoperationsincludedwithineachcategory,anddetailedschematicrepresentationofaconventionalwastewatertreatmentprocessescanbefoundinSpellman'sStandardHandbookforWastewaterOperators.isasummaryofthegenericadvantagesanddisadvantagesofvariouswastewatertreatmentprocessesasshowninliterature.Thesecharacteristicsgenerallyrelatetothecostofconstructionandeaseofoperation.Generally,thecomplexityandcostofwastewatertreatmenttechnologiesincreasewiththequalityoftheeffluentproduced.Infact,thewatermanagementandwastedisposalinthebreweryindustryareconsideredassignificantcostfactorsandimportantaspectsintheoperationsofabreweryplant.3.1PhysicalmethodsAmongthefirsttreatmentmethodsusedarephysicalunitoperations,inwhichphysicalforcesareappliedtoremovecontaminants.PhysicalMethodsremovecoarsesolidmatter,ratherthandissolvedpollutants.Itmaybeapassiveprocess,suchassedimentationtoallowsuspendedpollutantstosettleoutorfloattothetopnaturally.Ingeneral,thesemethodshaveyieldedlittlesuccess;mostoftenresultinginincompletecontaminantremovaland/orseparation.Forexample,sedimentationhasbeenfoundtobeunsatisfactoryevenwiththeadditionofcoagulantsandotheradditives.3.2.ChemicalmethodsDifferentchemicalscanbeaddedtothebrewerywastewatertoalterthewaterchemistry.ChemicalpretreatmentmayinvolvepHadjustmentorcoagulationandflocculation.Theaciditynoralkalinityofwastewateraffectsbothwastewatertreatmentandtheenvironment.LowpHindicatesincreasingaciditywhileahighpHindicatesincreasingalkalinity.ThepHofwastewaterneedstoremainbetween6and9toprotectorganisms.WasteCO2maybeusedtoneutralizecausticeffluentsfromclean-in-places(CIP)systemsandbottlewashers.ThewasteCO2canalsobeusedasacheapacidifyingagentfordecreasingthepHofalkalinewastewatersbeforetheanaerobicreactor,thusreplacingtheconventionallyusedacids.NeutralizationwithH2SO4andHClacidsisusuallynotrecommendedbecauseoftheircorrosivenatureandsulfateandchloridedischargelimitations,whichmayaddtothecostofeffluenttreatmentoperations.Coagulationandflocculationarephysicochemicalprocessescommonlyusedfortheremovalofcolloidalmaterialorcolorfromwaterandwastewater.Inwaterandwastewatertreatment,coagulationimpliesthestepwhereparticlesaredestabilizedbyacoagulant,andthismayincludetheformationofsmallaggregatesbyBrownianmotion(perikineticcoagulation).Ontheotherhand,thesubsequentprocessinwhichlargeraggregates(flocs)areformedbytheactionofshearisthenknownasflocculation.Aftersmallparticleshaveformedlargeraggregates,colloidalmaterialcanthenbemoreeasilyremovedbyphysicalseparationprocessessuchassedimentation,flotation,andfiltration.3.3.BiologicalmethodsBiologicalwastetreatmentprocessesplayacentralroleinthewaysocietymanagetheirwastewaters.Itisbasedontheactivityofawiderangeofmicroorganisms,convertingthebiodegradableorganicpollutantsinthewastewaters.Infact,breweryeffluentshavingbothchemical(withveryhighorganiccontent)andmicrobialcontaminantsaregenerallytreatedbybiologicalmethods.Therefore,afterthebrewerywastewaterhasundergonephysicalandchemicalpretreatments,thewastewatercanthenundergobiologicaltreatment.Comparedtophysicochemicalorchemicalmethods,biologicalmethodshavethreeadvantages:(1)thetreatmenttechnologyismature,(2)highefficiencyinCODandBODremoval,rangingfrom80to90%,and(3)lowinvestmentcost.However,thoughbiologicaltreatmentprocessesareparticularlyeffectiveforwastewatertreatment,theyrequireahighenergyinput.Biologicaltreatmentofwastewatercanbeeitheraerobic(withair/oxygensupply)oranaerobic(withoutoxygen).Theaerobicandanaerobicprocessesareshowngraphicallyin.Theseprocessesarediscussedinmoredetailsinthesubsequentsections.Generally,aerobictreatmenthassuccessfullybeenappliedforthetreatmentofbrewerywastewaterandrecentlyanaerobicsystemshavebecomeanattractiveoption.Presentsageneralcomparisonbetweenanaerobicandaerobicbiologicaltreatmentsystemssuchasactivatedsludge.4.TreatmentofbrewerywastewaterforreuseThedischargedwastewaterfromthebiologicalpretreatmentprocessescanbefurthertreated.Inthissectionvariousmethodsthatmaybeusedtotreatbrewerywastewaterforreuseareexplored.Itmustbenoted,however,thatrecyclingofregeneratedwaterasbrewingwaterisconsideredinappropriateandwouldrequirethatdrinkingwaterstandardsarecompliedwith.showsthemostimportantstandardsforrinsing,coolinganddrinkingwater.Amongtheparametersin,themostimportantparameterforrecyclingwaterorrequiredtobemeasuredistheCOD.CODisameasureoftheoxygenequivalentoftheorganicmattercontentofasamplethatisnsusceptibletooxidationbyastrongoxidant.TheCODisconsideredanappropriateindexforshowingtheamountoforganicsinwater.TheCODvalueofawastewatermainlyrepresentsthebiodegradableandnon-biodegradableorganiccomponents,althoughinorganiccompoundsmaybesignificantincertaincases.However,ingeneral,breweryeffluentsareeasilybiodegradablewithBOD/CODratiointherange0.6–0.7.Theorganiccomponentsinthebreweryeffluent(expressedasCOD)consistofsugars,solublestarch,ethanol,volatilefattyacids,etc.4.1theuseofcarbonnanotubesSincethe‘rediscovery’ofcarbonnanotubes(CNTs)in1991byIijima,severalresearchersworldwidecuttingacrossalldisciplineshaveembarkedonstimulatingresearchtoutilizethemyriaduniquepropertiesofthesenanomaterials.TheCNTsconsistofhoneycombstructuresofgraphenesheetsrolledupintocylinderswithadiameterofafewnanometers,butlengthofmanymicronorevencentimeters.Alotofmethodsandcarbonsourcesforthegrowthofcarbonnanotubeshavebeenactivelypursuedinthepastfewyears,andthesehavebeenoutlinedinseveralreviewpapers.TherearetypicallytwoformsofCNTsaccordingtothenumberofrolledupgraphenelayersthatformthetube,i.e.,single-walledcarbonnanotubes(SWCNT)andmulti-walledcarbonnanotubes(MWCNT).Themodelrepresentationsofmulti-walledCNTandsingle-walledCNTareshownin.TheuniquepropertiesofCNTsarisefromtheirspecialatomicandelectronicstructures.Owingtotheiruniquestructural,mechanical,andelectronicproperties,CNTspossessgreatpotentialinalargevarietyofpromisingapplicationssuchaschemicalsensors,fieldemissionmaterialsandcatalystsupports.SomeoftheimportantapplicationsofCNTswithrespecttowatertreatmentarediscussedbelow.4.2CarbonThecharacteristicsofawatertreatmentplanthaveagreatinfluenceonthecharacteristicpropertiesoftheendproduct.Evenwhentheincomingprocesswaterisfromamunicipaldrinkingwatersource,thewatermaycontainresidualtastes,odors,disinfectionby-products,andfreeandcombinedchlorine.Moleculeswithcarbon–sulfurbondsoftensmellandtastebad,buttheseareoftenpreferentiallyadsorbedoncarbon.Thesameistrueofmoleculeswitharomaticrings.Carbon'sde-chlorinatingcapabilityresultsfromitsabilitytoactasareducingagentthatreactswithstrongoxidizingagentssuchashypochlorousacidorchlorinedioxide.Thetreatmentoftannicacidforflavorandodorremovalisaprocessapplicationinbrewingwherecarbonadsorptionisused.Carbonisalsousedtoremovecolorfrommaltsforuseinclearbeersandotherflavoredmaltbeverages.Severalgranularandpowderedproductscanbeusedforthistypeofapplication.Activatedcarbonsareaneffectivetreatmenttoassurewaterthatiscontaminant,taste,andodorfree.5.DiscussionandsynthesisoffindingsnThissectionprovidesadiscussionandsynthesisofthereviewfindingsofthispaper.Thisdiscussionincludesacomparionandpossibleintegrationoftheprocessesandtechnologies.Inanutshell,thediscussionprimarilyaddressesthefollowingtwofundamentalquestions:(a)Howdotheprocessesandtechnologiescomparewitheachother?(b)Cantheybeintegratedwitheachother,andifso,whatarethepotentialchallengesandbenefits?5.1ComparisonofprocessesandtechnologiesThisreviewhighlightedtheneedfortreatmentofbrewerywastewater,andlookedatvariousmethodsthatmaybeusedtosafelyandcost-effectivelytreatbrewerywastewaterforreuse.Inaddition,somechallengesassociatedwiththesemethodswerediscussed.Itshouldbenotedandemphasizedhereinthatthetreatmentofbrewerywastewatereffluentisacostlyandrelativelycomplexactivity;particularlywiththeneedtomeetgovernmentalregulationsandenvironmentalfriendliness.Conventionalseparationmethodssuchascoagulation/flocculation,centrifugation,andgravityseparationexhibitshortcomingsincludingincompleteCODremoval.Thesemethodsaregenerallyassociatedwithlowseparationefficiency,highoperationcosts,largesetupsize,andthegenerationofsecondarypollutants.Itwasalsonoticedthatbiologicaltreatmentiswidelyappliedasapretreatmentmethod.Generally,aerobictreatmenthasbeenappliedforthetreatmentofbrewerywastewaterandrecently,anaerobicsystemshavebecomeanattractiveoption,amongotheradvantages,becauseoftheirhighCODcontentremoval.Thoughthesebiologicalmethodshavefoundwidespreadapplicationforthetreatmentofthecharacteristicallyhighorganiccontentofthebrewerywastewater,furthertreatmentisrequiredforwaterreuse.Nevertheless,thisreviewhasshownsomepromisingresultswithquenchedplasma,MBR,electrochemicalmethods,andmicrobialfuelcells.Thesemethodshavegreatpotentialtobeusedtotreatbrewerywastewaterforreuseandneedstobefurtherinvestigatedwithrespecttodifferentchallengesandopportunitiesinvolved.Forexample,beerbrewerywastewatermightbeagoodsourceforelectricitygenerationinMFCsduetoitsnatureofhighcarbohydratesandlowammonium–nitrogenconcentration.Theauthorshavealsonotedthatrecentadvancessuggestthatmanyoftherecentproblemsinvolvingwaterqualitycouldbesolvedorgreatlyamelioratedusingcarbonnanotubesassorbents.Therefore,itisexpectedthatthebreweryindustrywillalsobenefitfromthesediscoveries.However,theknowledgerequiredforthelarge-scaledesignandapplicationoftheprocessesdiscussedinthisreviewisperhapsstilllacking.Itisfurtherrecommendedtocarryoutsomestudiestoestablishestimatedcapitalcostsofthesepromisingprocesses.Ontheotherhand,theapplicationofmembranefiltration(e.g.,NFandRO)todrinkingwatertreatmentandwastewaterreuse,thoughwellestablished,hasundergoneaccelerateddevelopmentinthepastdecadewiththeimprovementinmembranequalityandthedecreaseinmembranecost.Averyimportanttrendinthedevelopmentofmembranefiltrationforwatertreatmentistheintegrationofdifferentpretreatmentstrategiestoimprovetheirperformance.TheRO,inparticular,hasbeenshowntobeanefficientandcosteffectiveprocessforthetreatmentofbrewerywastewaterforreuse.nshowsasummaryofsomeofthestudiesconductedonbrewerywastewater,showingtheCODreductions,andwhethertheeffluentissuitableasaprimaryorsecondarywaterbasedonthecriterialistedin.Itmustbenoted,however,thatthesestudieshaddifferentexperimentaldesigns.5.2IntegrationofprocessesandtechnologiesItcanbebeenseeninthatnoneofthemethods(apartfromRO)canbeusedindividuallyinbrewerywastewatertreatmentapplicationswithgoodeconomicsandhighdegreeofenergyefficiency.Couplingtheseprocessestogetherastwoorthreestageprocesseswouldbemoreappropriate.Subsequently,differentprocesscombinationsareproposedanddiscussed.Thedemandforrenewableenergyinoursocietyiseverincreasing.Therefore,theMFCsisrecommendedtobethefirstpretreat-mentstageofeveryintegratedprocessparticularlywithfiltrationtechniques.MFCshaveoperationalandfunctionaladvantagesoverthetechnologiescurrentlyusedforgeneratingenergyfromorganicmatter.First,thedirectconversionofsubstrateenergytoelectricityenableshighconversionefficiency,unlikethebiologicalprocessesreactorswherethemetabolizedproducts(e.g.,NH3)havetobeusedinboilersforenergygeneration.Second,MFCsoperateefficientlyatambienttemperature.Third,anMFCdoesnotrequiregastreatmentbecausetheoff-gassesofMFCsareenrichedincarbondioxideandnormallyhavenousefulenergycontent.Fourth,MFCsdonotneedenergyinputforaerationprovidedthecathodeispassivelyaerated.Fifth,MFCshavepotentialforwidespreadapplicationinlocationslackingelectricalinfrastructuresandcanalsooperatewithdiversefuelstosatisfyenergyrequirements.ThehighCODremovalefficiencycouldalsoreducetheloadinothercoupledstages.Theusesofothertechniquesasfirststagesinanintegratedprocessdonotofferanyforeseeablebenefits.Electrochemicalmethodscanbewellsuitedtobecoupledinthelatterstagesoftheintegratedprocess.Sanitizingagents(oftencalleddisinfectants)whicharepresentinbrewerywastewatercontainchlorinecompounds.Thesecompoundsproducechlorineduringelectrolysisand,thereafter,chlorinegenerateshypochlorousacidwhichoxidizesorganiccompounds.Chlorineisoneofthemostwidelyuseddisinfectants.Itisveryapplicableandveryeffectiveforthedeactivationofpathogenicmicroorganisms.Therefore,electrochemicalmethodsifcoupledinthelatterstagescanserveasanorganicoxidationanddisinfectingstage.Plasmamethodsthoughveryeffective,theprocessisexpensivebecauseofthehighenergyrequirementsbythegas,andthecostofenergysourcessuchaslaser.Therefore,ifcoupledwithothermethods,theprocessescanbeveryexpensive.CNTshaveshownremarkableadsorptionpower.CombiningCNTswithUFwillresultinsubstantialremovaloforganics.However,theadditionofCNTswouldrapidlyincreasethetransmembranepressurerapidlyduetotheformationofCNTcakeonthemembranesurface.Inthiscase,CNTsmayneedtobeoflargeenoughdiameterstoreducethetransmembranepressureeffect.AsfortheMBRorfiltrationingeneral,foulingmitigationcanpotentiallybedonebycouplingcoagulationandflocculationtotheprocess.n6.SummaryWaterisacommonelementinthelivesofallpeopleandsocieties.Waterhasbeenthefoundationandsometimes,theundoingofmanygreatcivilizations.Today,watercontinuestobeessentialforlifesustenance(bothhumanandanimals),agricultural,economicandindustrialactivitiesthathelpsocietytodevelop.Lessthanacenturyago,itwaswidelyassumedthattherewereenoughfreshwatersuppliesintheworldforeveryone.Yettoday,increaseduseoffreshwaterforindustrial,agricultural,anddomesticusehascreatedacutewatershortagesinsomeareasoftheworld,particularlythedevelopingcountries.Theseshortagesarestimulatingorworseninginternationalconflictsoverwater,whichhasjoinedoilasamajorcommoditytriggeringwars.Thepresenceofpollutantsinrawwaterduetohumanactivitieshasalsoexacerbatedthesituation.Ontheotherhand,wastewaterreclamationandreusehasbecomeanimportantoption,sinceindustrializationandurbanizationhaveacceleratedenvironmentalwaterpollution,makingitalimitedresourceforwatersupply.Whenproperlytreatedandrecycled,wastewatercanbeanalternativewatersourcethatcanbeneficiallyandcost-effectivelyreducethedemandsforfreshwater.Itcanbeconcludedthat,alongwiththegrowingworldpopulationandindustrialactivitiescoupledwithstringentenvironmentalrequirements,thecostofwaterisincreasing.Asaresult,thedemandforwaterreuseinthebreweryindustryisexpectedtoincreaseatanunprecedentedrate.Consequently,anincreasingneedofprocessescapableofachievinganefficienttreatmentunderextremeoperationalconditionsthatsimultaneouslyoptimizeoperationalcostscanbeexpectedinthefuture.Informationobtainedfromthisreviewshowsthatinordertoremoveimpuritiesefficiently,integrationofdifferentprocessesisrecommended.DisclaimerThecontentsofthispaperreflecttheviewsoftheauthorswhoareresponsibleforthefactsandaccuracyofthedatapresentedhereinanddonotnecessarilyreflecttheofficialviewsorpoliciesofanyagencyorinstitute.Thispaperdoesnotconstituteastandard,specification,norisitintendedfordesign,construction,bidding,contracting,orpermitpurposes.查看更多