以焦化氨为碱源用于锅炉烟道气脱硫的探讨

通过分析焦化氨水和H.P.F脱硫废液处理工艺,以及对氨法脱硫工艺进行详细的计算,提出了以焦化氨水和H.P.F脱硫废液中的氨为碱源对锅炉烟道气脱硫的新工艺。分析结果表明,由于回收了氨,使硫铵产能提高20%以上,减少外购98%浓硫酸2 109 kg/h。新工艺氨的来源能得到保证,同时也满足了燃煤锅炉应用高硫劣质煤种的环保要求。     

CL-20原料胺的工业制备方法

报道了 CL - 2 0原料胺的一种新的制备方法。在芳香醛存在下 ,苄基氯与氨水反应生成苄基胺 ,加入芳香醛可有效地抑制副产物二苄胺、三苄胺的生成 ,苄基胺的产率达到 70 %以上 ;反应物采用浓氨水可使反应体系体积缩小 ,提高生产能力 ,此方法设备简单 ,操作简便 ,采用密闭操作 ,防止空气污染 ,产率高 ,成本低 ,对降低 CL- 2 0的生产成本有重要意义     

水泥窑协同处置危废的氮氧化物排放调试分析

本文通过调试操作、烟气标定,理论计算分析脱硝系统运行的缺陷和问题。对SNCR系统技术改造后,通过增加高温风机和减少尾煤量等方式优化处置浆渣和废液的烧成条件,使分解炉出口的氧含量在1.5%左右,CO浓度控制在1 000 ×10-6左右。最后,脱硝系统使用0.90 m3/h氨水就能达到45%的氨水利用率,脱硝效率高达75%以上,以较低的氨氮比（NSR=1.68）实现烟囱的NOx排放≤150 mg/m3。     

现场电解制次氯酸钠在污水处理厂出水消毒的应用研究

随着污水厂出水排放标准日益提高,对排水中粪大肠菌群的控制也越来越严格。现场电解制次氯酸钠发生系统是一种较为理想的环境友好型氯消毒技术,能够有效杀灭城镇污水处理厂出水中的粪大肠杆菌。因原水水质不同,次氯酸钠的杀菌效果会有差异。次氯酸钠对原水中的氨氮有一定的去除作用,但是有可能氧化原水中残留的有机氮,从而使得氨氮含量重新升高。现场连续投加试验中,反应池次氯酸钠浓度为1．2mg／L,出水中的粪大肠菌群始终稳定达到GB18918-2002一级A标准的要求,且其他水质指标（如氨氮、COD等）良好。     

从氨氮废水中回收氨装置的技术改造

通过计算机优化设计，采用合适的塔内件及高效规整填料改造现有的浮阀塔，以其作氨解吸精馏装置。     

全自动定氮仪测定水体中氨氮的研究

氨氮是我国水体环境监测的主要指标,是各级监测站点的必测项目。本研究主要是比较水体中氨氮测定的两种方法（凯氏定氮法与钠氏试剂分光光度法）,主要测定了人工污水中氨氮,对全自动定氮仪的条件优化,并与钠氏试剂法进行比较。结果表明：全自动定氮仪测定水体中氨氮时最佳的条件：滴定所用盐酸浓度在0.03 mol/L比较适宜用于测定水体中的氨氮;定氮仪蒸馏氨氮时消化管中加入40%NaOH的体积数为10 mL。利用Foss-2300全自动定氮仪测定水体中的氨氮是一种方便、快捷,数据可靠,环保、新型的方法。     

气态膜吸收法脱除水中氨的传质效果

利用聚丙烯中空纤维气态膜对氨/水分离过程及影响因素进行研究,考察膜两侧液体流速、浓度、温度等工艺条件对传质系数和氨脱除率的影响。研究结果表明：气态膜-化学吸收法对氨/水有很好分离效果;原料液温度和流速的影响较为显著,传质系数随温度升高而升高,而提高原料液的流速,膜通量增加,氨的脱除率却下降,压力降升高;氨的初始浓度对膜通量影响较大,膜通量随初始浓度升高而增大;吸收液中反应物浓度相对于透过氨浓度过量时,吸收液的浓度、流速对传质过程影响较小。     

降低剩余氨水焦油含量的措施

介绍了安钢焦化厂剩余氨水处理系统的工艺流程,分析了剩余氨水焦油含量高的主要原因。采取的改进措施:在鼓冷工序增加了焦油氨水分离槽;将蒸氨工序原料槽改为除焦油槽,延长了焦油氨水的分离时间;加强了对剩余氨水槽及蒸氨原料除焦油槽的放油。通过改进,降低了剩余氨水中的焦油含量,由改进前的平均500mg/L以上降为200mg/L左右,改善了外排水质,具有较好的经济效益和社会效益。     

Numerical modeling and optimization of wastewater treatment using porous polymeric membranes

A new modeling approach was developed for prediction of ammonia removal from water by means of porous membranes. The model was based on adaptive neuro‐fuzzy interface system (ANFIS) to simulate ammonia stripping from water by means of hollow‐fiber membrane contactors. The predictions aimed to obtain optimum conditions for ammonia stripping using the Taguchi method. The initial concentrations of ammonia, pH of the ammonia solution, velocity of the feed, and the presence of excess ions in the ammonia feed solution were considered as the input properties. On the other hand, mass transfer coefficient was considered as output. The prediction results revealed that the pH of the ammonia feed has a significant effect on the separation of ammonia from water. The results also showed that the prediction of ANFIS model and experimental data match well and that the model can be used for prediction of porous membranes. Furthermore, simulated annealing was also used to determine controllable conditions to find the highest mass transfer coefficient. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers     

超重力强化干法脱硝制氨工艺

将超重力法氨水吹脱制氨技术用于选择性催化还原(SCR)脱硝工艺(需氨5vol%~10vol%),以空气?氨水为实验体系、旋转填料床为吹氨设备,考察了进气温度、超重力因子、气液体积比在装填不同填料时对脱氨率和产氨率的影响规律。结果表明,处理气量为4~10 m3/h时,丝网和乱堆两种不锈钢填料的吹脱率均随进气温度、超重力因子和气液体积比增大而增大;产氨率随进气温度和超重力因子增大而增大,随气液体积比增大而降低,产氨率达10%以上,与SCR法所需浓度一致,表明超重力氨水吹脱所制氨浓度可用于SCR脱硝。处理气量为50?700 m3/h时,吹脱浓度1wt%的氨氮废水,产氨率最大为3.0%。虽不满足SCR脱硝要求,但可将氨氮废水吹脱和氨水吹脱工艺相结合,节约氨水消耗量。     

Effect of low temperatures on polymorphic structures of cotton cellulose

Effects of low temperatures upon fine structures of cotton pretreated with either liquid ammonia or caustic of mercerizing strength were investigated. Temperatures of cotton after impregnation with liquid ammonia were lowered by (1) liquid nitrogen, (2) acetone–Dry Ice, (3) acetone, or (4) simple evaporation. With alkali-impregnated fabrics, temperature was lowered by immersion in liquid nitrogen. Changes in fine structure of ammonia- and alkali-celluloses were evaluated by x-ray diffraction before and after removal of each swelling reagent. After treatment with either ammonia or caustic soda, extent of crystalline modification was increased as temperature was reduced. X-ray diffractograms taken while liquid ammonia was still present indicated that the cellulose I structure of cotton sheeting was converted to cellulose III at liquid nitrogen temperatures; extent of conversion was approximately that obtained when a looser yarn structure was treated with liquid ammonia and the ammonia was removed by evaporation. When ammonia was removed with water, the cellulose I lattice was regenerated. In the presence of 23% NaOH, diffractograms indicated a significant decrease in order after a similar drop in temperature, but patterns were not of cellulose II until the NaOH was removed with water. Conversion to cellulose III or to cellulose II was achieved instantaneously when ammonia- and alkali-impregnated fabrics were immersed in liquid nitrogen.     

反渗透除氟除氨氮技术在饮用水中的应用

反渗透工艺可有选择地将氟离子、氨氮与水分离.水质监测表明,宁夏B市A水厂出水氟化物和氨氮浓度超标,针对现有工艺状况及水质特征,A厂采用了反渗透除氟除氨氮技术进行水质提标改造.为了节省投资及运行成本,采用原水+反渗透膜处理水勾兑方案,近远期勾兑比例分别为3.5:1和10:3.主体工艺为多介质过滤器+反渗透装置.长期运行的...     

Changes in wettability with time of plasma-modified perfluorinated polymers

Treatment of fluorinated ethylene propylene (FEP) and polytetrafluoroethylene (PTFE) by plasmas established in water vapour or ammonia gas enabled the rapid and facile modification of their surface chemistries. Under comparable plasma conditions, ammonia plasma exposures produced considerably lower air/water contact angles than water vapour plasmas. On storage of samples in air at ambient temperature, contact angles increased markedly within a few days on ammonia plasma-treated samples but remained constant over many weeks on water plasma-treated surfaces. Angle-dependent X-ray photoelectron spectroscopy (XPS) demonstrated a very low depth of modification in the case of ammonia plasma exposure, whereas the oxygen content of water plasma-treated samples was invariant with depth within the XPS analysis region. The long-term stability of water plasma-treated fluorocarbon polymer surfaces is believed to be due to this deep modification which prevents polymer chain reorientation, whereas the shallow modification in ammonia plasmas allows the rapid partial burial of the newly attached chemical groups inside the polymer. When ammonia plasma-treated samples stored in air were immersed in water, the contact angles remained constant, suggesting that the buried groups could not resurface. Contact angle measurements provided a simple and sensitive method for studying the time-dependent reduction in plasma treatment effects and the segmental mobility of modified fluorocarbon polymer surfaces; very shallow reorientation movements can be detected.     

MAP法处理中浓度氨氮废水的探讨

氮在水中主要是以有机氮和氨氮的形式存在的,污染受纳水体,影响水环境质量.高浓度氨氮废水可采用吹脱、汽提法去除.中、低浓度氨氮废水可采用MAP法沉氨预处理,除去大部分氨氮后,再经生物处理去除剩余的氨氮.MAP法去除中、低浓度的氨氮处理效果良好,并无二次污染.     

基于COSMO-SAC模型研究离子液体对氨水溶液汽液平衡的影响

采用COSMO-SAC模型研究了不同离子液体存在下氨水溶液的汽液相平衡,探讨了离子液体的亲水性、酸碱性、阴阳离子种类以及功能基团修饰等对氨的相对挥发度的影响。研究发现,不同性质的离子液体均会影响氨水系统的汽液相平衡。一般地,如果水与离子液体相互作用能高于氨与水的相互作用能,离子液体将有利于氨的逸出。当阴离子亲水性和形成氢键的能力越强,或者水与阴离子相互作用能越强,或者氨与阳离子相互作用能越弱,则离子液体越能促进氨水分离。水/离子液体之间的相互作用能与氨/水之间的相互作用能差值越大,离子液体越能提高氨的相对挥发度。当水与离子液体相互作用能低于氨与水的相互作用能时,离子液体也能促进低浓度下的氨水分离。阴离子要比阳离子更能影响氨的相对挥发度,其中氯离子([Cl]^-)、醋酸根离子([Ac]^-)型离子液体对促进氨水分离的效果更佳。对于甲基咪唑类阳离子([C _n mim]⁺,n=2、4、6、8),烷基链越长,越不利于氨的分离,但在[C₂mim]⁺上嫁接胺基(—NH₂)将会改善低浓度下氨水的分离效果。     

焦化蒸氨废水余热回收利用新技术开发与应用

针对传统焦化蒸氨废水工艺余热未全面回收利用的问题,设计开发了蒸氨废水余热回收利用新技术。通过蒸汽、热水两用型制冷、采暖双工况吸收式热泵机组,可夏季回收蒸氨废水余热制取热水,作为制冷机驱动热源制取工艺冷却水,满足煤气净化回收系统冷却需要,冬季回收蒸氨废水余热并辅以蒸汽为热源生产取暖水,实现了蒸氨废水余热的综合利用,降低了工序能耗,具有较好的经济效益和社会效益。     

二氧化碳气提法尿素装置中压吸收塔模拟分析

运用ChemCAD流程模拟软件对改进型二氧化碳气提法尿素装置的中压吸收塔进行了模拟分析,对吸收塔上段分别采用稀氨水和纯水为吸收剂时的两种工艺进行了模拟计算。模拟计算结果表明:吸收塔上段采用纯水吸收可使尾气氨排放得到有效控制,当纯水用量为80 kmol/h时,尾气中的氨摩尔分数从0.40%下降至0.02%,氨回收率可提高9.11%,年减少氨排放157.9 t。     

溴化锂吸收式冷水机组运行总结

利用溴化锂冷水机组制取低温冷水,用于降低合成氨生产过程中的气体温度,可以提高产量、降低能耗.分别介绍了溴化锂溶液的性质、冷水机组的工作原理、机组内部工作循环、运行效果及运行中的注意事项.使用溴化锂冷水机组后,合成氨产量提高20～25t/d,吨氨电耗下降约55 kW·h.     

带压处理焦炉循环氨水总管焊缝开裂

介绍了某公司捣回焦炉循环氨水总管焊缝开裂后,在不停氨水的情况下,采用在开裂焊缝的两侧30 mm处焊上一对法兰,法兰四周用螺栓拉固,促使开裂焊缝合拢,阻止氨水外漏,然后在拉固螺栓的外围打上抱箍,用1:1的水泥砂浆外加8%水玻璃浇注密封,取得了令人满意的效果.     

尿素装置停车实现"零"排放过程分析

大型尿素装置的生产过程中会产生大量的废水,在正常生产时都较容易回收利用,但在停车过程中将产生大量含氨的废水和废气,因为气相氨较难保存,所以停车时往往会有部分的氨排向空中而造成大气污染和氨的损失.通过对现有装置和停车方法进行改进将气相氨转变为氨水,待再次开车后回收利用,从而使装置停车实现"零"排放.