随着(zhe)工农(nong)业(ye)生产(chan)的(de)发展和人(ren)民生活水(shui)平的(de)提高，含氮化合物的(de)排(pai)放量急(ji)剧增加，已(yi)成为环境的(de)主要污染(ran)(ran)源，并引起各界的(de)关注。经(jing)济(ji)有效地(di)控制(zhi)氨氮废水(shui)污染(ran)(ran)已(yi)经(jing)成为当今环境工作者(zhe)所面临(lin)的(de)重大(da)课题。

1氨氮废水的来源

含氮(dan)(dan)(dan)物(wu)(wu)质进入(ru)(ru)水(shui)(shui)(shui)(shui)环境(jing)的(de)(de)途(tu)径主(zhu)要包括自然(ran)过(guo)程和(he)(he)(he)人(ren)类活(huo)动(dong)两个方面。含氮(dan)(dan)(dan)物(wu)(wu)质进入(ru)(ru)水(shui)(shui)(shui)(shui)环境(jing)的(de)(de)自然(ran)来(lai)源(yuan)(yuan)和(he)(he)(he)过(guo)程主(zhu)要包括降水(shui)(shui)(shui)(shui)降尘、非市区径流和(he)(he)(he)生(sheng)(sheng)(sheng)(sheng)物(wu)(wu)固(gu)氮(dan)(dan)(dan)等(deng)。人(ren)类的(de)(de)活(huo)动(dong)也是水(shui)(shui)(shui)(shui)环境(jing)中氮(dan)(dan)(dan)的(de)(de)重要来(lai)源(yuan)(yuan)，主(zhu)要包括未处理或处理过(guo)的(de)(de)城市生(sheng)(sheng)(sheng)(sheng)活(huo)和(he)(he)(he)工(gong)(gong)业废水(shui)(shui)(shui)(shui)、各种浸滤(lv)液(ye)和(he)(he)(he)地(di)(di)表(biao)径流等(deng)。人(ren)工(gong)(gong)合(he)成的(de)(de)化(hua)学肥料是水(shui)(shui)(shui)(shui)体(ti)中氮(dan)(dan)(dan)营养元(yuan)素的(de)(de)主(zhu)要来(lai)源(yuan)(yuan)，大(da)(da)量未被农作物(wu)(wu)利(li)用(yong)的(de)(de)氮(dan)(dan)(dan)化(hua)合(he)物(wu)(wu)绝(jue)大(da)(da)部分被农田排水(shui)(shui)(shui)(shui)和(he)(he)(he)地(di)(di)表(biao)径流带入(ru)(ru)地(di)(di)下水(shui)(shui)(shui)(shui)和(he)(he)(he)地(di)(di)表(biao)水(shui)(shui)(shui)(shui)中。随着石油、化(hua)工(gong)(gong)、食品和(he)(he)(he)制(zhi)药等(deng)工(gong)(gong)业的(de)(de)发展，以(yi)及人(ren)民生(sheng)(sheng)(sheng)(sheng)活(huo)水(shui)(shui)(shui)(shui)平的(de)(de)不断提(ti)高，城市生(sheng)(sheng)(sheng)(sheng)活(huo)污(wu)水(shui)(shui)(shui)(shui)和(he)(he)(he)垃圾渗滤(lv)液(ye)中氨氮(dan)(dan)(dan)的(de)(de)含量急(ji)剧上升。近年来(lai)，随着经济的(de)(de)发展，越来(lai)越多(duo)(duo)含氮(dan)(dan)(dan)污(wu)染物(wu)(wu)的(de)(de)任意排放(fang)给环境(jing)造成了极大(da)(da)的(de)(de)危害。氮(dan)(dan)(dan)在(zai)废水(shui)(shui)(shui)(shui)中以(yi)有(you)机态氮(dan)(dan)(dan)、氨态氮(dan)(dan)(dan)(NH4+-N)、硝态氮(dan)(dan)(dan)(NO3--N)以(yi)及亚硝态氮(dan)(dan)(dan)(NO2--N)等(deng)多(duo)(duo)种形(xing)(xing)式(shi)(shi)存在(zai)，而氨态氮(dan)(dan)(dan)是最(zui)主(zhu)要的(de)(de)存在(zai)形(xing)(xing)式(shi)(shi)之一。废水(shui)(shui)(shui)(shui)中的(de)(de)氨氮(dan)(dan)(dan)是指以(yi)游离(li)氨和(he)(he)(he)离(li)子(zi)铵形(xing)(xing)式(shi)(shi)存在(zai)的(de)(de)氮(dan)(dan)(dan)，主(zhu)要来(lai)源(yuan)(yuan)于生(sheng)(sheng)(sheng)(sheng)活(huo)污(wu)水(shui)(shui)(shui)(shui)中含氮(dan)(dan)(dan)有(you)机物(wu)(wu)的(de)(de)分解，焦(jiao)化(hua)、合(he)成氨等(deng)工(gong)(gong)业废水(shui)(shui)(shui)(shui)，以(yi)及农田排水(shui)(shui)(shui)(shui)等(deng)。氨氮(dan)(dan)(dan)污(wu)染源(yuan)(yuan)多(duo)(duo)，排放(fang)量大(da)(da)，并且排放(fang)的(de)(de)浓(nong)度变化(hua)大(da)(da)。

　　2氨(an)氮废水的危(wei)害

　　水环境中存在过量(liang)的氨氮会造成多方面的有害(hai)影响：

　　(1)由于NH4+-N的(de)氧(yang)化(hua)(hua)，会(hui)造成(cheng)(cheng)水(shui)体中溶解氧(yang)浓度(du)降低(di)，导致水(shui)体发黑(hei)发臭，水(shui)质下降，对水(shui)生(sheng)(sheng)动植(zhi)物的(de)生(sheng)(sheng)存造成(cheng)(cheng)影响。在有(you)利(li)的(de)环境条件下，废水(shui)中所含的(de)有(you)机氮将会(hui)转化(hua)(hua)成(cheng)(cheng)NH4+-N，NH4+-N是还(hai)原力最强的(de)无机氮形态，会(hui)进一步转化(hua)(hua)成(cheng)(cheng)NO2--N和NO3--N。根据(ju)生(sheng)(sheng)化(hua)(hua)反应计量关系，1gNH4+-N氧(yang)化(hua)(hua)成(cheng)(cheng)NO2--N消(xiao)耗氧(yang)气3.43g，氧(yang)化(hua)(hua)成(cheng)(cheng)NO3--N耗氧(yang)4.57g。

　　(2)水中(zhong)氮(dan)素含量太多会导致水体富营养化，进而(er)造成(cheng)一系列的(de)(de)(de)严重(zhong)后果(guo)。由(you)(you)于(yu)(yu)氮(dan)的(de)(de)(de)存在，致使光(guang)合微生(sheng)物(wu)(wu)(大多数为(wei)藻(zao)(zao)类(lei))的(de)(de)(de)数量增(zeng)加，即水体发生(sheng)富营养化现象，结果(guo)造成(cheng)：堵(du)塞(sai)滤(lv)池，造成(cheng)滤(lv)池运转周(zhou)期缩短(duan)，从而(er)增(zeng)加了水处理的(de)(de)(de)费用;妨(fang)碍水上运动;藻(zao)(zao)类(lei)代(dai)谢的(de)(de)(de)最(zui)终(zhong)产(chan)(chan)物(wu)(wu)可产(chan)(chan)生(sheng)引(yin)起有色度(du)和味道(dao)的(de)(de)(de)化合物(wu)(wu);由(you)(you)于(yu)(yu)蓝(lan)-绿藻(zao)(zao)类(lei)产(chan)(chan)生(sheng)的(de)(de)(de)毒素，家畜(chu)损(sun)伤，鱼类(lei)死(si)亡;由(you)(you)于(yu)(yu)藻(zao)(zao)类(lei)的(de)(de)(de)腐烂，使水体中(zhong)出现氧亏(kui)现象。

　　(3)水(shui)中(zhong)(zhong)的NO2--N和(he)NO3--N对人和(he)水(shui)生(sheng)生(sheng)物有(you)较大的危害作(zuo)(zuo)用。长期饮(yin)用NO3--N含量超过10mg/L的水(shui)，会发生(sheng)高铁(tie)血红(hong)(hong)蛋(dan)白(bai)(bai)症，当(dang)血液中(zhong)(zhong)高铁(tie)血红(hong)(hong)蛋(dan)白(bai)(bai)含量达到(dao)70mg/L，即发生(sheng)窒息。水(shui)中(zhong)(zhong)的NO2--N和(he)胺(an)(an)(an)作(zuo)(zuo)用会生(sheng)成亚硝(xiao)胺(an)(an)(an)，而亚硝(xiao)胺(an)(an)(an)是“三致”物质。NH4+-N和(he)氯(lv)(lv)反应会生(sheng)成氯(lv)(lv)胺(an)(an)(an)，氯(lv)(lv)胺(an)(an)(an)的消(xiao)毒作(zuo)(zuo)用比自由氯(lv)(lv)小，因此当(dang)有(you)NH4+-N存在时，水(shui)处(chu)理(li)厂将需要更大的加氯(lv)(lv)量，从而

　　增加处理成本。近年来，含(han)氨氮废水(shui)随意排放造(zao)成的人畜饮水(shui)困难(nan)甚至中(zhong)毒事件时有发生，我国长江、淮河(he)、钱塘江、四川沱(tuo)江等(deng)流域都有过(guo)(guo)相(xiang)(xiang)关报道，相(xiang)(xiang)应地区曾出现(xian)过(guo)(guo)诸如蓝藻污染(ran)导致(zhi)数(shu)百万居民生活饮水(shui)困难(nan)，以及相(xiang)(xiang)关水(shui)域受到了“牵连(lian)”等(deng)重大(da)事件，因(yin)此去除废水(shui)中(zhong)的氨氮已成为环境(jing)工作者研究的热点之一(yi)。

　　3氨(an)氮废水(shui)处理(li)的主要技术

　　目前，国内外氨(an)(an)氮废(fei)水处理(li)有折(zhe)点氯化法、化学沉淀法、离子交换法、吹脱法和生(sheng)物脱氨(an)(an)法等多(duo)种方法，这些(xie)技(ji)术可分(fen)为物理(li)化学法和生(sheng)物脱氮技(ji)术两大类(lei)。

　　3.1生物(wu)脱氮(dan)法

　　微(wei)生(sheng)物(wu)去除氨氮(dan)过程(cheng)需经两个阶(jie)段。第一阶(jie)段为(wei)(wei)硝(xiao)(xiao)(xiao)化(hua)过程(cheng)，亚(ya)硝(xiao)(xiao)(xiao)化(hua)菌和硝(xiao)(xiao)(xiao)化(hua)菌在有(you)氧(yang)条(tiao)件下将(jiang)氨态(tai)氮(dan)转化(hua)为(wei)(wei)亚(ya)硝(xiao)(xiao)(xiao)态(tai)氮(dan)和硝(xiao)(xiao)(xiao)态(tai)氮(dan)的过程(cheng)。第二阶(jie)段为(wei)(wei)反(fan)硝(xiao)(xiao)(xiao)化(hua)过程(cheng)，污(wu)水中的硝(xiao)(xiao)(xiao)态(tai)氮(dan)和亚(ya)硝(xiao)(xiao)(xiao)态(tai)氮(dan)在无(wu)氧(yang)或低氧(yang)条(tiao)件下，被反(fan)硝(xiao)(xiao)(xiao)化(hua)菌(异(yi)养(yang)、自养(yang)微(wei)生(sheng)物(wu)均有(you)发现且种(zhong)类(lei)很多(duo))还原转化(hua)为(wei)(wei)氮(dan)气。在此过程(cheng)中，有(you)机物(wu)(甲醇、乙酸(suan)、葡(pu)萄糖(tang)等)作为(wei)(wei)电子供(gong)(gong)体被氧(yang)化(hua)而提(ti)供(gong)(gong)能量。常(chang)见的生(sheng)物(wu)脱氮(dan)流程(cheng)可以分(fen)为(wei)(wei)3类(lei)，分(fen)别(bie)是多(duo)级(ji)污(wu)泥系统(tong)(tong)、单(dan)级(ji)污(wu)泥系统(tong)(tong)和生(sheng)物(wu)膜系统(tong)(tong)。

　　3.1.1多级污泥系统

　　此流(liu)程可以得到相当好(hao)的BOD5去除效果(guo)和脱氮(dan)效果(guo)，其缺点是流(liu)程长、构筑物多、基建费(fei)用(yong)高(gao)、需要外加碳源(yuan)、运行费(fei)用(yong)高(gao)、出水中残留一定量甲醇等。

　　3.1.2单(dan)级污泥系统

　　单级污泥(ni)系(xi)统(tong)的(de)形式包括前置反硝化系(xi)统(tong)、后置反硝化系(xi)统(tong)及交(jiao)(jiao)替(ti)工(gong)(gong)(gong)作(zuo)(zuo)系(xi)统(tong)。前置反硝化的(de)生(sheng)物脱(tuo)氮(dan)流(liu)(liu)程(cheng)，通常(chang)称为A/O流(liu)(liu)程(cheng)与传统(tong)的(de)生(sheng)物脱(tuo)氮(dan)工(gong)(gong)(gong)艺(yi)流(liu)(liu)程(cheng)相(xiang)比，A/O工(gong)(gong)(gong)艺(yi)具有流(liu)(liu)程(cheng)简(jian)单、构(gou)筑(zhu)物少、基建费用低、不需外加(jia)碳源、出水(shui)水(shui)质(zhi)高等优点。后置式反硝化系(xi)统(tong)，因(yin)为混(hun)合液(ye)缺(que)乏有机物，一般还需要人工(gong)(gong)(gong)投加(jia)碳源，但脱(tuo)氮(dan)的(de)效果可高于(yu)前置式，理论上(shang)可接近100%的(de)脱(tuo)氮(dan)。交(jiao)(jiao)替(ti)工(gong)(gong)(gong)作(zuo)(zuo)的(de)生(sheng)物脱(tuo)氮(dan)流(liu)(liu)程(cheng)主要由两个串联池子组成，通过改换进水(shui)和出水(shui)的(de)方(fang)(fang)向，两个池子交(jiao)(jiao)替(ti)在缺(que)氧和好氧的(de)条件(jian)下运(yun)行(xing)。该(gai)系(xi)统(tong)本质(zhi)上(shang)仍是(shi)A/O系(xi)统(tong)，但其(qi)(qi)利用交(jiao)(jiao)替(ti)工(gong)(gong)(gong)作(zuo)(zuo)的(de)方(fang)(fang)式，避免了混(hun)合液(ye)的(de)回流(liu)(liu)，因(yin)而脱(tuo)氮(dan)效果优于(yu)一般A/O流(liu)(liu)程(cheng)。其(qi)(qi)缺(que)点是(shi)运(yun)行(xing)管理费用较高，且一般必须配置计算(suan)机控制自动操(cao)作(zuo)(zuo)系(xi)统(tong)。

　　3.1.3生物膜系统

　　将上述A/O系(xi)(xi)统(tong)中的缺(que)氧(yang)池和好(hao)氧(yang)池改为固定(ding)生(sheng)物(wu)膜反(fan)应器(qi)，即形(xing)成生(sheng)物(wu)膜脱氮系(xi)(xi)统(tong)。此系(xi)(xi)统(tong)中应有混合液回(hui)流，但不需污泥回(hui)流，在(zai)缺(que)氧(yang)的好(hao)氧(yang)反(fan)应器(qi)中保存了适应于(yu)反(fan)硝(xiao)化(hua)(hua)和好(hao)氧(yang)氧(yang)化(hua)(hua)及硝(xiao)化(hua)(hua)反(fan)应的两个污泥系(xi)(xi)统(tong)。

　　3.2物化除氮

　　物化(hua)(hua)除氮常用的物理化(hua)(hua)学(xue)方法(fa)有折(zhe)点氯化(hua)(hua)法(fa)、化(hua)(hua)学(xue)沉淀法(fa)、离子交换法(fa)、吹脱法(fa)、液膜法(fa)、电渗析(xi)法(fa)和(he)催化(hua)(hua)湿式氧(yang)化(hua)(hua)法(fa)等。

　　3.2.1折点氯化法

　　不连续点氯(lv)化法(fa)是氧化法(fa)处理氨(an)氮废水(shui)的(de)(de)一种，利用(yong)在(zai)水(shui)中的(de)(de)氨(an)与氯(lv)反应生成氮气而将水(shui)中氨(an)去除的(de)(de)化学(xue)处理法(fa)。该方(fang)法(fa)还(hai)(hai)可(ke)以(yi)起到(dao)杀菌作用(yong)，同时使一部分有(you)(you)机(ji)物(wu)无机(ji)化，但经氯(lv)化处理后的(de)(de)出(chu)水(shui)中留有(you)(you)余氯(lv)，还(hai)(hai)应进一步脱氯(lv)处理。

　　在含(han)有氨(an)的(de)水中投加次氯酸HClO，当pH值在中性附近时，随次氯酸的(de)投加，逐步进行下(xia)述主要反应：

　　NH3+HClO→NH2Cl+H2O①

　　NH2Cl+HClO→NHCl2+H2O②

　　NH2Cl+NHCl2→N2+3H++3Cl-③

　　投加氯(lv)(lv)量(liang)和氨氮之比(bi)(简称Cl/N)在(zai)5.07以(yi)下时，首先进行①式(shi)反应(ying)，生(sheng)成(cheng)一(yi)氯(lv)(lv)胺(NH2Cl)，水(shui)(shui)中(zhong)(zhong)(zhong)余(yu)氯(lv)(lv)浓度(du)(du)增大(da)，其后(hou)，随着(zhe)次(ci)(ci)氯(lv)(lv)酸投加量(liang)的(de)增加，一(yi)氯(lv)(lv)胺按②式(shi)进行反应(ying)，生(sheng)成(cheng)二(er)氯(lv)(lv)胺(NHCl2)，同时进行③式(shi)反应(ying)，水(shui)(shui)中(zhong)(zhong)(zhong)的(de)N呈N2被去除。其结果是，水(shui)(shui)中(zhong)(zhong)(zhong)的(de)余(yu)氯(lv)(lv)浓度(du)(du)随Cl/N的(de)增大(da)而(er)减小，当(dang)Cl/N比(bi)值达到某个(ge)数(shu)值以(yi)上时，因(yin)未反应(ying)而(er)残留(liu)的(de)次(ci)(ci)氯(lv)(lv)酸(即游离余(yu)氯(lv)(lv))增多，水(shui)(shui)中(zhong)(zhong)(zhong)残留(liu)余(yu)氯(lv)(lv)的(de)浓度(du)(du)再(zai)次(ci)(ci)增大(da)，这个(ge)最小值的(de)点(dian)称为(wei)不连续点(dian)(习惯称为(wei)折(zhe)点(dian))。此时的(de)Cl/N比(bi)按理论(lun)计算(suan)为(wei)7.6;废水(shui)(shui)处理中(zhong)(zhong)(zhong)因(yin)为(wei)氯(lv)(lv)与废水(shui)(shui)中(zhong)(zhong)(zhong)的(de)有(you)机物(wu)反应(ying)，C1/N比(bi)应(ying)比(bi)理论(lun)值7.6高些，通常为(wei)10。此外，当(dang)pH不在(zai)中(zhong)(zhong)(zhong)性(xing)范围时，酸性(xing)条件下多生(sheng)成(cheng)三氯(lv)(lv)胺，在(zai)碱性(xing)条件下生(sheng)成(cheng)硝(xiao)酸，脱氮效率降低。

　　在pH值(zhi)为6～7、每mg氨(an)氮(dan)氯(lv)投加量为10mg、接(jie)触0.5～2.0h的情(qing)况下(xia)，氨(an)氮(dan)的去除(chu)率为90%～100%。因此此法对低浓度氨(an)氮(dan)废水适用。

　　处(chu)理(li)(li)(li)时(shi)所需的(de)(de)实际氯(lv)(lv)气(qi)量(liang)取决(jue)于温度(du)、pH及氨氮(dan)浓(nong)度(du)。氧化每mg氨氮(dan)有时(shi)需要9～10mg氯(lv)(lv)气(qi)折(zhe)点，氯(lv)(lv)化法(fa)处(chu)理(li)(li)(li)后的(de)(de)出水在排放前一般需用活性(xing)炭或(huo)SO2进(jin)行反氯(lv)(lv)化，以(yi)除去水中残余的(de)(de)氯(lv)(lv)。虽然氯(lv)(lv)化法(fa)反应迅速，所需设备投资少(shao)，但液氯(lv)(lv)的(de)(de)安全使(shi)用和贮存(cun)要求高(gao)，且处(chu)理(li)(li)(li)成本也(ye)较高(gao)。若用次氯(lv)(lv)酸或(huo)二(er)氧化氯(lv)(lv)发(fa)生(sheng)装置(zhi)代替液氯(lv)(lv)，会更(geng)安全且运(yun)行费用可以(yi)降低，目前国内的(de)(de)氯(lv)(lv)发(fa)生(sheng)装置(zhi)的(de)(de)产(chan)氯(lv)(lv)量(liang)太小，且价格昂(ang)贵。因此氯(lv)(lv)化法(fa)一般适用于给水的(de)(de)处(chu)理(li)(li)(li)，不太适合处(chu)理(li)(li)(li)大水量(liang)高(gao)浓(nong)度(du)的(de)(de)氨氮(dan)废水。

　　3.2.2化(hua)学沉淀(dian)法

　　化(hua)学(xue)沉(chen)(chen)淀法是往水(shui)中投加某种化(hua)学(xue)药剂，与水(shui)中的溶解(jie)(jie)性(xing)物质(zhi)发生(sheng)反应(ying)，生(sheng)成难(nan)溶于水(shui)的盐类，形成沉(chen)(chen)渣易去除，从而(er)降低水(shui)中溶解(jie)(jie)性(xing)物质(zhi)的含量。当(dang)在含有NH4+的废水(shui)中加入PO43-和Mg2+离子时，会发生(sheng)如下(xia)反应(ying)：

　　NH4++PO43-+Mg2+→MgNH4PO4↓④生成难溶于(yu)水(shui)(shui)的(de)MgNH4PO4沉淀(dian)物(wu)，从而(er)达(da)到去除(chu)(chu)水(shui)(shui)中氨(an)氮(dan)的(de)目的(de)。采用的(de)常见沉淀(dian)剂是Mg(OH)2和H3PO4，适宜的(de)pH值(zhi)范围为9.0～11，投(tou)加质量比H3PO4/Mg(OH)2为1.5～3.5。废(fei)水(shui)(shui)中氨(an)氮(dan)浓度小于(yu)900mg/L时，去除(chu)(chu)率在90%以上(shang)，沉淀(dian)物(wu)是一种很好的(de)复合肥料。由于(yu)Mg(OH)2和H3PO4的(de)价(jia)格比较贵，成本较高，处理高浓度氨(an)氮(dan)废(fei)水(shui)(shui)可(ke)行，但该法向废(fei)水(shui)(shui)中加入(ru)了(le)PO43-，易造成二次(ci)污染(ran)。

　　3.2.3离子交(jiao)换法

　　离(li)子(zi)交(jiao)换(huan)(huan)法的实质是(shi)(shi)(shi)不溶(rong)性(xing)离(li)子(zi)化合物(wu)(离(li)子(zi)交(jiao)换(huan)(huan)剂)上的可交(jiao)换(huan)(huan)离(li)子(zi)与废水中的其它(ta)同(tong)性(xing)离(li)子(zi)的交(jiao)换(huan)(huan)反应，是(shi)(shi)(shi)一(yi)种(zhong)特殊的吸附(fu)过程(cheng)，通常是(shi)(shi)(shi)可逆(ni)性(xing)化学吸附(fu)。沸石是(shi)(shi)(shi)一(yi)种(zhong)天然离(li)子(zi)交(jiao)换(huan)(huan)物(wu)质，其价格远低于(yu)阳离(li)子(zi)交(jiao)换(huan)(huan)树(shu)脂，且(qie)对NH4+-N具有选择性(xing)的吸附(fu)能

　　力(li)，具(ju)有(you)(you)(you)较高的(de)阳离(li)(li)子(zi)交(jiao)换(huan)容(rong)(rong)量(liang)(liang)，纯丝(si)光沸石(shi)和斜发沸石(shi)的(de)阳离(li)(li)子(zi)交(jiao)换(huan)容(rong)(rong)量(liang)(liang)平均为(wei)每(mei)100g相(xiang)当于213和223mg物质的(de)量(liang)(liang)(m.e)。但实际(ji)天然(ran)沸石(shi)中(zhong)(zhong)含有(you)(you)(you)不纯物质，所(suo)以纯度较高的(de)沸石(shi)交(jiao)换(huan)容(rong)(rong)量(liang)(liang)每(mei)100g不大(da)(da)于200m.e，一般为(wei)100～150m.e。沸石(shi)作为(wei)离(li)(li)子(zi)交(jiao)换(huan)剂(ji)，具(ju)有(you)(you)(you)特殊的(de)离(li)(li)子(zi)交(jiao)换(huan)特性(xing)，对(dui)离(li)(li)子(zi)的(de)选择(ze)交(jiao)换(huan)顺(shun)序(xu)是：Cs(Ⅰ)>Rb(Ⅰ)>K(Ⅰ)>NH4+>Sr(Ⅰ)>Na(Ⅰ)>Ca(Ⅱ)>Fe(Ⅲ)>Al(Ⅲ)>Mg(Ⅱ)>Li(Ⅰ)。工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)设(she)计(ji)(ji)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)用(yong)(yong)(yong)中(zhong)(zhong)，废(fei)(fei)(fei)水(shui)(shui)(shui)(shui)pH值(zhi)(zhi)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)调(diao)整(zheng)(zheng)到(dao)(dao)6～9，重(zhong)(zhong)金(jin)(jin)(jin)属(shu)(shu)大(da)(da)体(ti)(ti)上(shang)(shang)(shang)没有(you)(you)(you)什(shen)(shen)么(me)(me)Rb(Ⅰ)>K(Ⅰ)>NH4+>Sr(Ⅰ)>Na(Ⅰ)>Ca(Ⅱ)>Fe(Ⅲ)>Al(Ⅲ)>Mg(Ⅱ)>Li(Ⅰ)。工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)设(she)计(ji)(ji)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)用(yong)(yong)(yong)中(zhong)(zhong)，废(fei)(fei)(fei)水(shui)(shui)(shui)(shui)pH值(zhi)(zhi)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)调(diao)整(zheng)(zheng)到(dao)(dao)6～9，重(zhong)(zhong)金(jin)(jin)(jin)属(shu)(shu)大(da)(da)体(ti)(ti)上(shang)(shang)(shang)没有(you)(you)(you)什(shen)(shen)么(me)(me)K(Ⅰ)>NH4+>Sr(Ⅰ)>Na(Ⅰ)>Ca(Ⅱ)>Fe(Ⅲ)>Al(Ⅲ)>Mg(Ⅱ)>Li(Ⅰ)。工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)设(she)计(ji)(ji)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)用(yong)(yong)(yong)中(zhong)(zhong)，废(fei)(fei)(fei)水(shui)(shui)(shui)(shui)pH值(zhi)(zhi)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)调(diao)整(zheng)(zheng)到(dao)(dao)6～9，重(zhong)(zhong)金(jin)(jin)(jin)属(shu)(shu)大(da)(da)体(ti)(ti)上(shang)(shang)(shang)没有(you)(you)(you)什(shen)(shen)么(me)(me)NH4+>Sr(Ⅰ)>Na(Ⅰ)>Ca(Ⅱ)>Fe(Ⅲ)>Al(Ⅲ)>Mg(Ⅱ)>Li(Ⅰ)。工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)设(she)计(ji)(ji)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)用(yong)(yong)(yong)中(zhong)(zhong)，废(fei)(fei)(fei)水(shui)(shui)(shui)(shui)pH值(zhi)(zhi)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)调(diao)整(zheng)(zheng)到(dao)(dao)6～9，重(zhong)(zhong)金(jin)(jin)(jin)属(shu)(shu)大(da)(da)体(ti)(ti)上(shang)(shang)(shang)没有(you)(you)(you)什(shen)(shen)么(me)(me)Sr(Ⅰ)>Na(Ⅰ)>Ca(Ⅱ)>Fe(Ⅲ)>Al(Ⅲ)>Mg(Ⅱ)>Li(Ⅰ)。工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)设(she)计(ji)(ji)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)用(yong)(yong)(yong)中(zhong)(zhong)，废(fei)(fei)(fei)水(shui)(shui)(shui)(shui)pH值(zhi)(zhi)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)调(diao)整(zheng)(zheng)到(dao)(dao)6～9，重(zhong)(zhong)金(jin)(jin)(jin)属(shu)(shu)大(da)(da)体(ti)(ti)上(shang)(shang)(shang)没有(you)(you)(you)什(shen)(shen)么(me)(me)Na(Ⅰ)>Ca(Ⅱ)>Fe(Ⅲ)>Al(Ⅲ)>Mg(Ⅱ)>Li(Ⅰ)。工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)设(she)计(ji)(ji)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)用(yong)(yong)(yong)中(zhong)(zhong)，废(fei)(fei)(fei)水(shui)(shui)(shui)(shui)pH值(zhi)(zhi)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)调(diao)整(zheng)(zheng)到(dao)(dao)6～9，重(zhong)(zhong)金(jin)(jin)(jin)属(shu)(shu)大(da)(da)体(ti)(ti)上(shang)(shang)(shang)没有(you)(you)(you)什(shen)(shen)么(me)(me)Ca(Ⅱ)>Fe(Ⅲ)>Al(Ⅲ)>Mg(Ⅱ)>Li(Ⅰ)。工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)设(she)计(ji)(ji)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)用(yong)(yong)(yong)中(zhong)(zhong)，废(fei)(fei)(fei)水(shui)(shui)(shui)(shui)pH值(zhi)(zhi)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)调(diao)整(zheng)(zheng)到(dao)(dao)6～9，重(zhong)(zhong)金(jin)(jin)(jin)属(shu)(shu)大(da)(da)体(ti)(ti)上(shang)(shang)(shang)没有(you)(you)(you)什(shen)(shen)么(me)(me)Fe(Ⅲ)>Al(Ⅲ)>Mg(Ⅱ)>Li(Ⅰ)。工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)设(she)计(ji)(ji)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)用(yong)(yong)(yong)中(zhong)(zhong)，废(fei)(fei)(fei)水(shui)(shui)(shui)(shui)pH值(zhi)(zhi)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)调(diao)整(zheng)(zheng)到(dao)(dao)6～9，重(zhong)(zhong)金(jin)(jin)(jin)属(shu)(shu)大(da)(da)体(ti)(ti)上(shang)(shang)(shang)没有(you)(you)(you)什(shen)(shen)么(me)(me)Al(Ⅲ)>Mg(Ⅱ)>Li(Ⅰ)。工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)设(she)计(ji)(ji)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)用(yong)(yong)(yong)中(zhong)(zhong)，废(fei)(fei)(fei)水(shui)(shui)(shui)(shui)pH值(zhi)(zhi)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)调(diao)整(zheng)(zheng)到(dao)(dao)6～9，重(zhong)(zhong)金(jin)(jin)(jin)属(shu)(shu)大(da)(da)体(ti)(ti)上(shang)(shang)(shang)没有(you)(you)(you)什(shen)(shen)么(me)(me)Mg(Ⅱ)>Li(Ⅰ)。工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)设(she)计(ji)(ji)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)用(yong)(yong)(yong)中(zhong)(zhong)，废(fei)(fei)(fei)水(shui)(shui)(shui)(shui)pH值(zhi)(zhi)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)调(diao)整(zheng)(zheng)到(dao)(dao)6～9，重(zhong)(zhong)金(jin)(jin)(jin)属(shu)(shu)大(da)(da)体(ti)(ti)上(shang)(shang)(shang)没有(you)(you)(you)什(shen)(shen)么(me)(me)Li(Ⅰ)。工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)设(she)计(ji)(ji)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)用(yong)(yong)(yong)中(zhong)(zhong)，废(fei)(fei)(fei)水(shui)(shui)(shui)(shui)pH值(zhi)(zhi)应(ying)(ying)(ying)(ying)(ying)(ying)(ying)调(diao)整(zheng)(zheng)到(dao)(dao)6～9，重(zhong)(zhong)金(jin)(jin)(jin)属(shu)(shu)大(da)(da)体(ti)(ti)上(shang)(shang)(shang)没有(you)(you)(you)什(shen)(shen)么(me)(me)

　　影(ying)响(xiang);碱金属、碱土金属中(zhong)除Mg以(yi)外都有影(ying)响(xiang)，尤其是Ca对(dui)沸石的离子交换能力影(ying)响(xiang)比Na和(he)(he)K更大。沸石吸附饱和(he)(he)后必(bi)须进行再(zai)(zai)(zai)生(sheng)(sheng)，以(yi)采用(yong)再(zai)(zai)(zai)生(sheng)(sheng)液(ye)法(fa)为主，燃烧法(fa)很(hen)少(shao)用(yong)。再(zai)(zai)(zai)生(sheng)(sheng)液(ye)多采用(yong)NaOH和(he)(he)NaCl。由(you)于(yu)废(fei)水中(zhong)含(han)有Ca2+，致使(shi)沸石对(dui)氨(an)的去除率呈(cheng)不可逆性(xing)的降(jiang)低，要(yao)考(kao)虑补充(chong)和(he)(he)更新。

　　3.2.4吹脱法(fa)

　　吹(chui)(chui)脱(tuo)法是将废水(shui)调(diao)节至碱性，然(ran)后在(zai)汽(qi)提塔中通(tong)入(ru)空(kong)(kong)气(qi)或蒸汽(qi)，通(tong)过气(qi)液接触(chu)将废水(shui)中的(de)游离(li)氨吹(chui)(chui)脱(tuo)至大(da)气(qi)中。通(tong)入(ru)蒸汽(qi)，可升高废水(shui)温(wen)度，从而提高一定(ding)pH值时(shi)被吹(chui)(chui)脱(tuo)的(de)氨的(de)比(bi)率。用(yong)该(gai)法处理氨时(shi)，需考虑(lv)排放(fang)的(de)游离(li)氨总量(liang)应符合(he)氨的(de)大(da)气(qi)排放(fang)标准，以免造成二(er)次污(wu)染(ran)。低(di)浓度废水(shui)通(tong)常(chang)(chang)(chang)在(zai)常(chang)(chang)(chang)温(wen)下(xia)用(yong)空(kong)(kong)气(qi)吹(chui)(chui)脱(tuo)，而炼钢(gang)、石(shi)油化(hua)(hua)工、化(hua)(hua)肥、有机(ji)化(hua)(hua)工有色(se)金属冶炼等(deng)行(xing)业的(de)高浓度废水(shui)则常(chang)(chang)(chang)用(yong)蒸汽(qi)进行(xing)吹(chui)(chui)脱(tuo)。具(ju)体联(lian)系污(wu)水(shui)宝或参(can)见(jian)//www.dowater.com更多相关(guan)技术文档。

　　3.2.5液膜法

　　自从(cong)(cong)1986年黎念之发现(xian)乳状(zhuang)液(ye)膜(mo)以来，液(ye)膜(mo)法得(de)到了广泛的(de)(de)(de)研究。许多人认为(wei)液(ye)膜(mo)分(fen)离(li)法有可能成(cheng)为(wei)继萃取法之后的(de)(de)(de)第二代分(fen)离(li)纯化技术，尤(you)其(qi)适用(yong)于低浓度金(jin)属离(li)子提纯及废水处(chu)理等过程。乳状(zhuang)液(ye)膜(mo)法去除氨氮的(de)(de)(de)机理是：氨态氮NH3-N易溶于膜(mo)相(xiang)油相(xiang)，它从(cong)(cong)膜(mo)相(xiang)外高浓度的(de)(de)(de)外侧(ce)，通过膜(mo)相(xiang)的(de)(de)(de)扩散(san)迁移，到达(da)膜(mo)相(xiang)内侧(ce)与内相(xiang)界面(mian)(mian)，与膜(mo)内相(xiang)中(zhong)的(de)(de)(de)酸发生解脱反应，生成(cheng)的(de)(de)(de)NH4+不(bu)溶于油相(xiang)而稳定(ding)在(zai)膜(mo)内相(xiang)中(zhong)，在(zai)膜(mo)内外两侧(ce)氨浓度差的(de)(de)(de)推动下，氨分(fen)子不(bu)断(duan)通过膜(mo)表面(mian)(mian)吸附(fu)、渗透(tou)扩散(san)迁移至膜(mo)相(xiang)内侧(ce)解吸，从(cong)(cong)而达(da)到分(fen)离(li)去除氨氮的(de)(de)(de)目的(de)(de)(de)。

　　3.2.6电渗析法

　　电(dian)渗析是一种膜(mo)(mo)法分离(li)(li)技(ji)术，其利用施加在(zai)阴阳膜(mo)(mo)对(dui)之(zhi)间(jian)的(de)(de)电(dian)压去除水(shui)溶(rong)液中(zhong)(zhong)溶(rong)解的(de)(de)固体。在(zai)电(dian)渗析室(shi)的(de)(de)阴阳渗透(tou)(tou)膜(mo)(mo)之(zhi)间(jian)施加直流电(dian)压，当进水(shui)通过多对(dui)阴阳离(li)(li)子渗透(tou)(tou)膜(mo)(mo)时，铵离(li)(li)子及其他离(li)(li)子在(zai)施加电(dian)压的(de)(de)影响下，通过膜(mo)(mo)而进入另一侧的(de)(de)浓(nong)水(shui)中(zhong)(zhong)并(bing)在(zai)浓(nong)水(shui)中(zhong)(zhong)集，因而从进水(shui)中(zhong)(zhong)分离(li)(li)出来。

　　3.2.7催化(hua)湿式氧(yang)化(hua)法

　　催化(hua)湿式氧化(hua)法(fa)是(shi)20世纪80年(nian)代国际上(shang)发展起来的(de)(de)(de)一种治理废水(shui)(shui)的(de)(de)(de)新技术。在一定(ding)温度、压力(li)和(he)(he)催化(hua)剂作用(yong)下，经(jing)(jing)(jing)空气氧化(hua)，可使污水(shui)(shui)中的(de)(de)(de)有(you)机物(wu)和(he)(he)氨分(fen)别氧化(hua)分(fen)解(jie)成CO2、N2和(he)(he)H2O等无害物(wu)质，达到(dao)净(jing)化(hua)的(de)(de)(de)目的(de)(de)(de)。该(gai)法(fa)具有(you)净(jing)化(hua)效率高(gao)(废水(shui)(shui)经(jing)(jing)(jing)净(jing)化(hua)后可达到(dao)饮(yin)用(yong)水(shui)(shui)标准)、流程(cheng)简单、占地面积少等特(te)点(dian)。经(jing)(jing)(jing)多年(nian)应用(yong)与实践，这一废水(shui)(shui)处理方法(fa)的(de)(de)(de)建设(she)及运行费(fei)用(yong)仅为常规方法(fa)的(de)(de)(de)60%左(zuo)右，因而在技术上(shang)和(he)(he)经(jing)(jing)(jing)济上(shang)均具有(you)较强的(de)(de)(de)竞(jing)争力(li)。

　　4结论

　　国内外氨(an)氮废(fei)(fei)(fei)水(shui)降解的(de)(de)各(ge)种技(ji)术(shu)与(yu)工(gong)(gong)(gong)艺(yi)过程，都有(you)(you)(you)(you)各(ge)自(zi)的(de)(de)优势与(yu)不足，由于不同废(fei)(fei)(fei)水(shui)性(xing)(xing)质上的(de)(de)差异，还没有(you)(you)(you)(you)一种通用(yong)(yong)的(de)(de)方(fang)法(fa)(fa)能处(chu)(chu)理(li)所(suo)有(you)(you)(you)(you)的(de)(de)氨(an)氮废(fei)(fei)(fei)水(shui)。因此，必须针对(dui)不同工(gong)(gong)(gong)业过程的(de)(de)废(fei)(fei)(fei)水(shui)性(xing)(xing)质，以及废(fei)(fei)(fei)水(shui)所(suo)含(han)的(de)(de)成分进行深入系统(tong)地(di)研究，选择和确定处(chu)(chu)理(li)技(ji)术(shu)及工(gong)(gong)(gong)艺(yi)。目前，生物脱氮法(fa)(fa)主(zhu)要用(yong)(yong)于含(han)有(you)(you)(you)(you)机物的(de)(de)低氨(an)氮浓度(du)化工(gong)(gong)(gong)废(fei)(fei)(fei)水(shui)和生活污水(shui)的(de)(de)处(chu)(chu)理(li)，该(gai)法(fa)(fa)技(ji)术(shu)可靠(kao)，处(chu)(chu)理(li)效果好。对(dui)于高浓度(du)氨(an)氮废(fei)(fei)(fei)水(shui)主(zhu)要采用(yong)(yong)吹(chui)脱法(fa)(fa)，近年来兴(xing)起的(de)(de)膜法(fa)(fa)分离(li)技(ji)术(shu)及催(cui)化湿式氧化等方(fang)法(fa)(fa)具有(you)(you)(you)(you)很好的(de)(de)应(ying)用(yong)(yong)前景。