Effect and mechanism of coking residual ammonia water treating by flue gas

ＩｎｔｒｏｄｕｃｔｉｏｎＣｏｋｉｎｇｗａｓｔｅｗａｔｅｒ,ｅｓｐｅｃｉａｌｌｙｔｈｅｃｏｋｉｎｇｒｅｓｉｄｕａｌａｍｍｏｎｉａｗａｔｅｒ(ａｈｕｇｅｖｏｌｕｍｅａｎｄｈｅａｖｙｐｏｌｌｕｔｅｄｗａｓｔｅｗａｔｅｒｉｎｃｏｋｉｎｇ)ｉｓａｈｉｇｈｃｏｎｃｅｎｔｒａｔｉｏｎｏｒｇａｎｉｃｉｎｄｕｓｔｒｙｗａｓｔｅｗａｔｅｒｏｆｄｉｆｆｉｃｕｌｔｆｏｒｔｈｅｂｉｏｃｈｅｍｉｓｔｒｙｄｅｇｒａｄａｔｉｏｎ.Ｏｆｗｈｉｃｈ,ＢＯＤ5/ＣＯＤｉｓｕｓｕａｌｌｙａｂｏｕｔ30%.Ａｔｐｒｅｓｅｎｔ,ｂｙｔｈｅｔｒｅａｔｍ…     

烟道气处理焦化剩余氨水的研究

发明专利“烟道气处理焦剩余氨水或全部废水的方法”在江苏淮钢集团焦化剩余氨水处理工程中获得成功应用，它不仅有效地处理了焦化剩余氨水，实现了废水零排放，而且烟道气达标外排，对烟道气还有脱硫的效果。     

利用燃煤锅炉烟道气处理工业废水的理论与实践

阐述了燃煤锅炉烟道气的主要化学成分及处理废水的机理 ,介绍了锅炉烟道气处理废水的研究与应用     

Experimental and mechanism studies on seawater flue gas desulfurization

ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｓｔａｌｌａｔｉｏｎｏｆｓｃｒｕｂｂｅｒｓｏｒｔｈｅｕｓｅｏｆｌｏｗｓｕｌｆｕｒ ｃｏｎｔａｉｎｉｎｇｃｏａｌａｒｅｔｗｏｏｐｔｉｏｎｓｕｓｅｄｂｙｐｏｗｅｒｐｌａｎｔｓｔｏｒｅｄｕｃｅＳＯ2 ｅｍｉｓｓｉｏｎｓ.ＴｈｅｍａｊｏｒｉｔｙｏｆｐｏｗｅｒｐｌａｎｔｓｃｏｎｔｒｏｌＳＯ2 ｅｍｉｓｓｉｏｎｓｕｓｉｎｇｌｉｍｅｂａｓｅｄｓｃｒｕｂｂｉｎｇ ,ａｌｔｈｏｕｇｈｔｈｉｓｄｅｓｕｌｆｕｒｉｚａｔｉｏｎｐｒｏｃｅｓｓｈａｓａｎｕｍｂｅｒｏｆａｄｖａｎｔａｇｅｓ,ｉｔａｌｓｏｈ…     

Desulfurizing absorbent for flue gas and its absorption mechanism

A new desulfurizing absorbent for flue gas,i.e.,an organic physical solvent of DMSO(dimethyl sulfoxide) mixed with a relatively small amount of chemical solvent(Mn^2 ) was studied.Compared with pure physical solvent of DMSO,the purification efficiency of the new absorbent was improved .And its absorption and reaction mechanism are discussed.     

荷电喷雾脱硫实验与机理分析

对湿法烟气脱硫系统引入静电效应后产生的脱硫增益作用进行了实验测定，清水水雾和石灰液浆滴荷电前后的脱硫效率比较实验结果表明，对于中等SO2浓度，这种效应可使雾滴或浆滴脱硫效率增加8个百分点左右，理论分析指出，荷电对强化烟气脱硫是有益的，雾滴或浆滴带电后本质上提高了雾滴的表面活性，改善了脱硫通道中雾滴的弥散程度，从而加速了SO2的吸收进程。     

焦煤比对烧结烟气中挥发性有机物排放特性的影响

采用PF-300便携式甲烷、总烃、非甲烷总烃测试仪对烧结杯实验产生的烟气进行挥发性有机物含量分析,研究了烧结燃料焦煤比对烟气挥发性有机物排放特性的影响,结果表明：挥发性有机物在烧结过程中持续释放,其排放趋势与NOx相一致;TVOCs和MHC的生成与煤粉和焦粉的挥发分有显著的相关性,以煤粉为主要燃料时,适当配加焦粉不仅对TVOCs和MHC具有物理减排效应,还存在煤焦混合协同减排的效应.同时对国内某钢铁烧结机进行TVOCs排放浓度及分样组成检测,表明：该钢铁烧结机烟气中挥发性有机物排放浓度较高,其结果与烧结杯实验所得曲线一致;烧结工序VOCs分样检测主要化合物为乳酸乙酯、丙酮、苯、甲苯、正己烷等.     

Coupling mechanism of activated carbon mixed with dust for flue gas desulfurization and denitrification

To clarify the effect of coking dust, sintering dust and fly ash on the activity of activated carbon for various industrial flue gas desulfurization and denitrification, the coupling mechanism of the mixed activated carbon and dust was investigated to provide theoretical reference for the stable operation. The results show that coking dust had 34% desulfurization efficiency and 10% denitrification efficiency; correspondingly, sintering dust and fly ash had no obvious desulfurization and denitrification activities. For the mixture of activated carbon and dust, the coking dust reduced the desulfurization and denitrification efficiencies by blocking the pores of activated carbon, and its inhibiting effect on activated carbon was larger than its own desulfurization and denitrification activity. The sintering dust also reduced the desulfurization efficiency on the activated carbon while enhancing the denitrification efficiency. Fly ash blocked the pores of activated carbon and reduced its reaction activity. The reaction activity of coking dust mainly came from the surface functional groups, similar to that of activated carbon. The reaction activity of sintering dust mainly came from the oxidative property of Fe₂O₃, which oxidized NO to NO₂ and promoted the fast selectively catalytic reduction (SCR) of NO to form N₂. Sintering dust was activated by the joint action of activated carbon, and both had a coupling function. Sintering dust enhanced the adsorption and oxidation of NO, and activated carbon further promoted the reduction of NO_x by NH₃; thus, the denitrification efficiency increased by 5%-7% on the activated carbon.     

氨水洗涤脱除CO2温室气体的机理研究

利用氨水洗涤电厂模拟烟气中的CO2温室气体，在合适的操作条件下，可以实现很高的CO2脱除率(达到95％以上)；当入口CO2体积分数分别为10％、12％、140k，氨水吸收CO2的脱除率超过90％时，进口CO2体积分数对氨水吸收CO2脱除率的影响不大；随着氨水浓度的增加，氨水吸收CO2的吸收速率和达到平衡状态时CO2的脱除率都要增大；氨水洗涤CO2温室气体的动力学研究表明：在实验所涉及的温度区间内，其化学反应符合Arrhenius规律。     

A critical review on the technique and mechanism of microwave-based denitrification in flue gas

Microwave radiation has received extensive attention due to its significant thermal and non-thermal effects, and the development of MW-based denitrification in flue gas has become one of the most promising methods to avoid the defects of ammonia escape, high temperature and cost in traditional SCR. This review introduces the thermal and non-thermal effects of microwaves and divides MW-based denitrification methods into MW reduction and oxidation denitrification, systematically summarizes these denitrification methods, including MW discharge reduction, MW-induced catalytic reduction using active carbon, molecular sieves, metal oxides (transition metals, perovskites, etc.), MW-induced oxidation denitrification with and without additional oxidant, and discusses their removal pathway and mechanism. Finally, several research prospects and directions regarding the development of microwave-based denitrification methods are provided.     

粉煤灰对烟气中CO2的吸收特性及矿物相演变机理研究

粉煤灰矿化CO₂是一种极具前景的减少燃煤电厂CO₂排放的技术.然而,目前还缺乏从矿物学角度对碳酸化反应机理的详细认识.本研究选取了3种粉煤灰开展碳酸化实验和矿物学研究,考察碳酸化过程中温度对碳酸化能力及粉煤灰矿物学变化的影响.结果表明,在任一温度下,BJ粉煤灰的碳酸化率均高于YA和LY粉煤灰,这是由于BJ粉煤灰中硬石膏、钙铁石和无定形相等活性矿物相含量较高,LY粉煤灰缺少高活性的钙、镁结晶相.对YA粉煤灰而言,升高温度可显著提高透辉石、尖晶石、黑钙铁矿和方镁石的转化率.在碳酸化YA粉煤灰中同时检测出碳酸钙和碳酸镁/铁,说明除含钙相其他活性元素(Mg和Fe)也参与了碳酸化过程.因此,需要对每个粉煤灰原始材料的矿物学和操作温度进行具体的个案优化,以最大限度地提高固定CO₂能力和碳酸化率.结果还表明温度对不同晶型碳酸钙的形成具有重要作用.方解石在低温(40和80℃)下形成,而文石在高温(180和220℃)下形成.     

基于硫循环的烟气生化脱硫及硫磺回收的过程机理

以元素硫的地球化学循环为指导,系统研究硫酸盐还原菌（SRB）生化代谢产物还原性硫化物与亚硫酸根的反应过程机理及产物形态.结果表明,在生化烟气脱硫及硫回收反应体系中,pH=（4.04±0.10）、ORP=（-134±17mV）时硫磺产量最大,硫磺产率大于40%;SO₂（aq）-S^2-（aq）体系证明pH=（3.99±0.21）、ORP=（-159±40）mV、SO₃^2-/ΣS^2-物质的量比约1：1时为产硫磺最佳条件区间;S₂O₃^2-与S^2-的产硫磺反应为副反应,有利于硫磺的产生;近中性条件下硫磺的消耗归因于产多硫化物和连多硫酸盐反应的进行;SO₂（aq）-S^2-（aq）体系和生化体系的固体产物表征分析为球状高纯斜方硫,生化体系产生的硫磺被胞外多聚物粘附裹挟.     

Removal of adhesive dusts from flue gas using corona discharges with spraying water

Effective removal of adhesive and fine dusts from flue gas is very difficult. A new method of electrostatic precipitation of the corona discharges with spraying water(CDSW) was introduced. A new electrode configuration and the circulation spraying of water were employed in the method. The efficient electrostatic precipitation for adhesive and fine dusts can be accomplished without any drain water during a long operating period. The fundamental structure, discharge characteristics, mechanism of spraying and precipitation principle of the electrostatic precipitation using CDSW were described and analyzed. The V-I characteristics, spraying state, supplying water quantity, influence of temperature and clean of the electrodes were researched in series experiments. The treating effects of circulating spraying using the corona plasma at the same time of electrostatic precipitation were investigated. The fundamental theories and experimental data were proposed, in order to effectively remove the adhesive dusts from flue gas using CDSW in practice.     

离子色谱法测定烟气中的氟和氯

采用试验对比研究的方法测试武汉某玻璃窑烟气中氟和氯的浓度,结果表明:采用EPA Method 26A方法进行采样,一次采样可获得气态氟、气态氯、卤化氢和卤素浓度等多个数据,相对误差小,具备节省时间和人力的优势。分析烟气吸收液优化的色谱条件:设定EG40淋洗液自动发生器KOH浓度为30 mmol/L;淋洗液流速为1.2 mL/min;进样量为25 μL。该方法相对标准偏差小于3.0%,精密度高,样品加标平均回收率为96.7%~104.3%,准确度良好,完全满足烟气样品吸收液氟离子和氯离子浓度的检测要求。     

Transformation and removal of ammonium sulfate aerosols and ammonia slip from selective catalytic reduction in wet flue gas desulfurization system

Selective catalytic reduction (SCR) denitration may increase the emission of NH₄⁺ and NH₃. The removal and transformation characteristics of ammonium sulfate aerosols and ammonia slip during the wet flue gas desulfurization (WFGD) process, as well as the effect of desulfurization parameters, were investigated in an experimental system equipped with a simulated SCR flue gas generation system and a limestone-based WFGD system. The results indicate that the ammonium sulfate aerosols and ammonia slip in the flue gas from SCR can be partly removed by slurry scrubbing, while the entrainment and evaporation of desulfurization slurry with accumulated NH₄⁺ will generate new ammonium-containing particles and gaseous ammonia. The ammonium-containing particles formed by desulfurization are not only derived from the entrainment of slurry droplets, but also from the re-condensation of gaseous ammonia generated by slurry evaporation. Therefore, even if the concentration of NH₄⁺ in the desulfurization slurry is quite low, a high level of NH₄⁺ was still contained in the fine particles at the outlet of the scrubber. When the accumulated NH₄⁺ in the desulfurization slurry was high enough, the WFGD system promoted the conversion of NH₃ to NH₄⁺ and increased the additional emission of primary NH₄⁺ aerosols. With the decline of the liquid/gas ratio and flue gas temperature, the removal efficiency of ammonia sulfate aerosols increased, and the NH₄⁺ emitted from entrainment and evaporation of the desulfurization slurry decreased. In addition, the volatile ammonia concentration after the WFGD system was reduced with the decrease of the NH₄⁺ concentration and pH values of the slurry.     

Nitrification and denitrification in biological activated carbon filter for treating high ammonia source water

Since the ammonia in the effluent of the traditional water purification process could not meet the supply demand, the advanced treatment of a high concentration of NH₄ ⁺-N micro-polluted source water by biological activated carbon filter (BACF) was tested. The filter was operated in the downflow manner and the results showed that the removing rate of NH₄ ⁺-N was related to the influent concentration of NH₄ ⁺-N. Its removing rate could be higher than 95% when influent concentration was under 1.0 mg/L. It could also decrease with the increasing influent concentration when the NH₄ ⁺-N concentration was in the range from 1.5 to 4.9 mg/L and the dissolved oxygen (DO) in the influent was under 10 mg/L, and the minimum removing rate could be 30%. The key factor of restricting nitrification in BACF was the influent DO. When the influent NH₄ ⁺-N concentration was high, the DO in water was almost depleted entirely by the nitrifying and hetetrophic bacteria in the depth of 0.4 m filter and the filter layer was divided into aerobic and anoxic zones. The nitrification and degradation of organic matters existed in the aerobic zone, while the denitrification occurred in the anoxic zone. Due to the limited carbon source, the denitrification could not be carried out properly, which led to the accumulation of the denitrification intermediates such as NO₂ ⁻. In addition to the denitrification bacteria, the nitrification and the heterotrophic bacteria existed in the anoxic zone. __________ Translated from Environmental Science, 2006, 27(1): 69–73 [译自: 环境科学]     

反硝化菌对烟气汞吸附特性研究

采用反硝化菌对烟气中Hg~0、Hg~(2+)的吸附特性进行研究,反硝化菌对Hg~0和Hg~(2+)吸附性能良好,在pH为8、初始Hg~0(Hg~(2+))浓度为95.7μg·m-3(0.4μg·L-1)和吸附剂用量为0.35 g·L-1时,Hg~0和Hg~(2+)的吸附效率分别达到43.01%和98.12%.反硝化菌吸附Hg~0的过程遵循拟一级动力学,符合Langmuir等温吸附模型,最大吸附容量为126.1μg·g-1.反硝化菌吸附Hg~(2+)遵循拟二级动力学模型,符合Langmuir等温吸附模型,最大吸附容量为36.23μg·g-1.采用傅里叶红外光谱(FTIR)和热场发射环境扫描电镜-能谱电子背散射衍射系统(EDS)表征吸附前后的反硝化菌,结果表明吸附过程中细菌表面的糖环、磷酸及脂肪化合物基团发挥了吸附汞作用.     

络合-氧化-还原耦合方法脱除烟气中NOx的研究

NO与Fe2+反应生成络合物[Fe(NO)]2+易被O2氧化解络形成NO2-和NO3-离子,进而被尿素溶液还原生成N2.基于上述反应原理,本文提出脱除烟气中NOx的新方法,即以FeSO4为吸收液、O2为氧化剂、尿素为还原剂的络合-氧化-还原耦合法.考察了尿素初始浓度、吸收液pH值、NOx初始浓度、烟气流量等因素对NOx脱除率的影响.结果表明,尿素初始浓度越高、吸收液pH值越低、NOx初始浓度越大、烟气流量越小时,NOx脱除率越高;当尿素初始浓度为1.19mol/L,吸收液pH值为3.2,NOx初始浓度为1493mg/m3以及烟气流量为800mL/min时,反应初期(0~6min)NOx脱除率可达92%以上,且反应1h后脱除率仍可保持在69%左右.     

Effect of activated NH3 on SO2 removal by pulse coronadischarge plasma in flue gas

ＩｎｔｒｏｄｕｃｔｉｏｎＮｏｗＳＯ2 ｉｓｔｈｅｏｎｅｏｆｍａｉｎｇａｓｐｏｌｌｕｔａｎｔｓａｎｄｔｈｅｍａｉｎｃａｕｓｅｏｆａｃｉｄｒａｉｎｐｒｏｂｌｅｍ .ＳＯ2ｒｅｍｏｖａｌｂｙ ｐｕｌｓｅｃｏｒｏｎａｄｉｓｃｈａｒｇｅｉｓａｎｅｗＤｅ ＳＯ2 ｔｅｃｈｎｉｑｕｅｄｅｖｅｌｏｐｅｄｄｕｒｉｎｇｌａｓｔｔｅｎ ｙｅａｒｓ(Ｍａｓｕｄａ ,1 993;Ｍｉｚｕｎｏ ,1 986 ;Ｄｉｎｅｌｌｉ,1 990 ) .ＳＯ2 ｉｎｆｌｕｅｇａｓｉｓｏｘｉｄｉｚｅｄｂｙａｃｔｉｖａｔｅｄｒａｄｉｃａｌ(ｓｕｃｈａｓＯＨ ,ＨＯ2 ,ＮＨ2 ,Ｏ)ｗ…     

疏水性分子筛对焦化废水生物处理尾水的吸附过程解析

采用表面活性剂为模板剂常温一步合成疏水性介孔分子筛(MCM-41-dry)和通过煅烧去除模板剂得到亲水性介孔材料(MCM-41-cal).分别以制备的两种分子筛作为吸附剂吸附焦化废水生物出水中COD和TOC组分,考察吸附剂浓度、pH值等对吸附过程的影响,并对吸附过程进行动力学拟合.结果表明,MCM-41-dry的吸附效果远远强于MCM-41-cal,归因于含有模板剂的材料表面具有较强的疏水性及含有高吸附容量的季铵基团.在25℃、吸附剂浓度为2g·L-1时,MCM-41-dry对焦化废水中COD和TOC的去除率分别达53%和66%,吸附量分别为64mg·g-1和17mg·g-1.拟二级动力学模型能够真实反映整个吸附过程.水样吸附前后的GC/MS数据表明,焦化废水生物出水中残留了长链烷烃、卤代物、多环芳烃等难降解有机物,经MCM-41-dry吸附后,各种物质浓度均得到降低,MCM-41-dry尤其对疏水性烷烃类有较好的吸附效果,表明该吸附剂能够优先吸附疏水性物质.此外,吸附剂对水具有一定的润湿性能,能与废水充分接触,从而利于其吸附水中的污染物,这使其用于实际废水的处理成为可能.