高硫煤的微波脱硫研究

考查了高硫煤直接微波处理、浸渍不同浓度NaOH溶液后微波处理及其与磁选相结合的手段对脱硫效率的影响,结果表明:高硫煤样直接经微波辐照处理具有一定的脱硫效果,但脱硫率较低。原煤经不同NaOH溶液浸渍后,再经微波处理,其脱硫效果明显提高。在采用2 mol/L NaOH溶液浸渍后,经700W微波功率处理60s,其脱硫率达到最大,为45.2%。磁选对脱硫效率的影响受微波功率的影响较大。在本实验条件下,采用900W微波功率处理,经磁选后脱硫率明显提高。     

微波协同铁屑内电解处理亚甲基蓝染料废水

利用微波辐照协同铁屑内电解处理亚甲基蓝染料废水。结果表明,在600 W微波功率辐照下,30 mL铁屑协同处理50 mL的50 mg/L的亚甲基蓝废水1 m in,废水的脱色率达到99%以上,且铁屑可以重复利用8次。通过SEM表明,铁屑在微波辐照下,表面遍及蜂窝状凹孔,比表面积增大,使内电解效率提高。     

活性炭微波再生及其在焦化废水处理中的应用

采用微波辐照方法对废活性炭进行再生实验,研究发现微波功率是影响其再生效率最重要的因素,实验中废活性炭的再生效率可高达85.3％。将经微波辐照再生得到的活性炭再用来处理焦化废水,实验结果表明,其对焦化废水的处理效果佳,COD去除率最高可达到80.7％。     

Microwave Drying of Wood Strands

Characteristics of microwave drying of wood strands with different initial moisture contents and geometries were investigated using a commercial small microwave oven under different power inputs. Temperature and moisture changes along with the drying efficiency were examined at different drying scenarios. Extractives were analyzed using gas chromatography/mass spectrometry (GC/MS). The results showed that the microwave drying process consisted of three distinct periods (warm-up period, evaporation period, and heating-up period) during which the temperature, moisture change, and drying efficiency could vary. Most of the extractives were remnant during microwave drying. It was observed that with proper selections of power input, weight of drying material, and drying time, microwave drying could increase the drying rate, save up to 50% of energy consumption, and decrease volatile organic compound (VOC) emissions when compared with the conventional drying method.     

Microwave Drying of Wood Strands

Abstract

Characteristics of microwave drying of wood strands with different initial moisture contents and geometries were investigated using a commercial small microwave oven under different power inputs. Temperature and moisture changes along with the drying efficiency were examined at different drying scenarios. Extractives were analyzed using gas chromatography/mass spectrometry (GC/MS). The results showed that the microwave drying process consisted of three distinct periods (warm-up period, evaporation period, and heating-up period) during which the temperature, moisture change, and drying efficiency could vary. Most of the extractives were remnant during microwave drying. It was observed that with proper selections of power input, weight of drying material, and drying time, microwave drying could increase the drying rate, save up to 50% of energy consumption, and decrease volatile organic compound (VOC) emissions when compared with the conventional drying method.     

Simultaneous removal of SO2 and NOx by microwave with potassium permanganate over zeolite

Simultaneous sulfur dioxide (SO₂) and nitrogen oxides (NO_x) removal from flue gas can be achieved with high efficiency by microwave with potassium permanganate (KMnO₄) over zeolite. The experimental results showed that the microwave reactor could be used to oxidation of SO₂ to sulfate with the best desulfurization efficiency of 96.8% and oxidize NO_x to nitrates with the best NO_x removal efficiency of 98.4%. Microwave accentuates catalytic oxidation treatment, and microwave addition can increase the SO₂ and NO_x removal efficiency by 7.2% and 12.2% separately. The addition of zeolite to microwave potassium permanganate increases from 16.5% to 43.5% the microwave removal efficiency for SO₂, and the NO_x removal efficiency from 85.6% to 98.2%. The additional use of potassium permanganate to the microwave zeolite leads to the enhancement of SO₂ removal efficiency up from 53.9% to 95%, and denitrification efficiency up from 85.6% to 98.2%. The optimal microwave power and empty bed residence time (EBRT) on simultaneous desulfurization and denitrification are 259 W and 0.357 s, respectively. SO₂ and NO_x were rapidly oxidized in microwave induced catalytic oxidation reaction using potassium permanganate with zeolite being the catalyst and microwave absorbent.     

Treatment of an industrial chemical waste‐water using a granular activated carbon adsorption‐microwave regeneration process

BACKGROUND: Industrial waste‐water is posing an ever‐greater environmental hazard. Recently, a process for purification combining activated carbon adsorption and microwave regeneration has drawn much attention. In this study, the effectiveness of this process for the treatment of industrial waste‐water from a chemical plant was tested. RESULTS: The effects of various factors including solution pH, granular activated carbon (GAC) dosage and contact time on the adsorption efficiency of organic compounds were studied. The regeneration of the exhausted GAC under microwave radiation was investigated, and the optimal conditions were: microwave power 400 W, radiation time 3 min for 10 g GAC. Under the optimal conditions the regenerated GAC recovered 97.6% of its original adsorption capacity. Repetitive uses of the GAC showed that it maintained a stable performance in the first few repetitions, but a decrease was observed after further repetitions. A GAC weight loss of about 10% at the sixth repetition was observed and a decrease in the surface area and increase in the surface basicity were observed for the regenerated GAC. Economic evaluation of the microwave regeneration process suggested that the total cost was about 24.3% of the GAC price at a pilot scale. CONCLUSIONS: A satisfactory regeneration of the chemical waste‐water exhausted GAC could be achieved under microwave radiation. The GAC adsorption‐microwave regeneration process was applicable for the treatment of this chemical waste‐water. Copyright © 2012 Society of Chemical Industry     

微波-活性炭催化法处理亮绿溶液的研究

以亮绿为研究对象，研究在活性炭存在和通入空气的条件下，微波辐射处理染料废水的可行性及其影响处理过程的因素和影响规律。结果表明：1．微波可加速亮绿裂解和被氧化的速度；2．增加微波辐射电压、处理时间和活性炭用量，均能提高该法处理亮绿溶液的脱色率；3．微波辐射—活性炭吸附催化法处理亮绿溶液(废水)有较好的可行性，在1：14的固液比下，微波辐射30min，可达到98．69％的脱色率。     

The treatment of anaerobically digested palm oil mill effluent by pressurised activated sludge

The application of the pressurised activated sludge process in the secondary treatment of anaerobically digested liquor of palm oil mill effluent (POME) as influent under various physical conditions was studied. Separation of the particulates was by way of a dissolved air flotation unit. Results showed that a high efficiency in pollutant removals could be achieved and the final treated water was of good effluent quality. The high efficiency of the process was linked to the high rate of oxygen transfer at elevated pressure in the reactor. With a dissolved oxygen level of 10–14 mg dm^?3 in the reactor, filamentous growth and sludge bulking were prevented. The kinetic coefficients for the process were also evaluated. It is envisaged the process could complement the anaerobic digestion in a two-stage complete treatment system for POME.     

氯化钠对改性沸石微波脱除氨氮效果的影响

通过添加助剂NaCl在微波下对天然沸石进行加热制备环境材料,研究了微波后沸石对再生水中氨氮的去除效果。研究发现,助剂预处理可以大大提高微波沸石的脱氮效果。在沸石与NaCl溶液固液比1:50,NaCl溶液浓度4%,343 W的微波功率加热4 min的条件下,微波沸石环境材料对氨氮的去除效果最好,最佳去除率可达99.70%;单独进行343 W、4 min的微波加热沸石对氨氮的去除率为76.46%;相对于天然沸石,上述两种微波沸石对氨氮去除率分别提高了39%、15.76%。通过SEM、EDS、XRD等表征手段对微波前后的沸石分析发现,在微波加热过程中助剂氯化钠的加入使沸石颗粒表面更加松散,出现了更多的孔道,同时天然沸石Ca、Mg、P、S峰消失,主衍射峰强度有所减弱,出现了部分非晶化特征。     

微波技术在油田采出废水处理中的作用

The process of microwave flocculation and Fe/C micro-electrolysis was used to treat several oilfield production wastewater, and the effects of microwave on flocculation, disinfection, de-oiling and decrease of the corrosion rate were investigated.The results showed that microwave coagulation could reduce 20% dosage for PAC and 30% for PAM, and the settling time of microwave flocculation was only 1/4 of normal flocculation, and total removal efficiency of COD for the wastewater reached 96%.Microwave could effectively kill total growth bacteria (TGB) and sulfate-reducing bacteria (SRB) in the wastewater, and the removal of bacteria reached 99%.Microwave accelerated oil-water separation and promoted emulsion-breaking simutaneously, and the average removal efficiency of oil was 95%.Microwave also played an active role in the reduction of corrosion rate, and the average corrosion reduction reached 90% in the microwave assisted process, which was 10 points higher than that in normal process.     

高酸值废弃油脂制备生物柴油的预酯化

为了有效解决现有酯化体系中存在反应慢、时间长、产能低等问题,提出了一种高温下甲醇连续酯化反应的新技术,并采用该技术以对甲苯磺酸为催化剂催化高酸值废弃油脂预酯化试验研究。系统讨论了不同酯化方法对反应的影响,并着重研究了工艺条件对预酯化效果的影响。实验结果表明:高温下甲醇连续酯化的新技术可显著提高酯化反应效率,在反应温度120℃、甲醇流量4.0mL/min、催化剂加入量0.8%的条件下,酯化率达98.8%以上,可将油脂的酸值降至1.0mgKOH/g以下,满足下一步酯交换制备生物柴油的要求;并基于实验研究的基础上将该技术工艺对不同酸值的废弃油脂进行了放大试验研究,皆取得了较好的酯化效果,为产业化、规模化的应用提供理论依据和参数指导。     

盐酸-乙二醇-水介质高效预处理山核桃壳及其糖化工艺

为了提高木质纤维素的酶解效率,采用盐酸辅助乙二醇对山核桃壳进行预处理。通过油浴的处理方式优化得出的最佳预处理条件为:处理介质为盐酸-乙二醇-水(1.2%:88.8%:10%,质量分数)的混合物,预处理温度为130℃,预处理时间为30min。为了减小预处理的温度和时间,采用微波辐射的辅助预处理,最佳预处理条件为:微波辐射温度100℃,微波辐射时间5min,微波辐射功率200W。糖化预处理后的山核桃壳经水解72h后,其还原糖产率可达到88.6%(油浴)和74.2%(微波)。利用电镜(SEM)和红外光谱(FT-IR)分析油浴和微波预处理后的山核桃壳,可以发现山核桃壳紧密的结构遭到破坏,变成更加易于酶解的松散、多孔结构,增加了酶可及度,因此很大程度上提高了糖化率。可见,盐酸-乙二醇-水溶液高效预处理可以提高山核桃壳酶解糖化的效率。     

Experimental and theoretical study of microwave enhanced catalytic hydrodesulfurization of thiophene in a continuous-flow reactor

Hydrodesulfurization (HDS) of thiophene, as a gasoline model oil, over an industrial Ni-Mo/Al₂O₃ catalyst was investigated in a continuous system under microwave irradiation. The HDS efficiency was much higher (5%–14%) under microwave irradiation than conventional heating. It was proved that the reaction was enhanced by both microwave thermal and non-thermal effects. Microwave selective heating caused hot spots inside the catalyst, thus improved the reaction rate. From the analysis of the non-thermal effect, the molecular collisions were significantly increased under microwave irradiation. However, instead of being reduced, the apparent activation energy increased. This may be due to the microwave treatment hindering the adsorption though upright S-bind (η¹) and enhancing the parallel adsorption (η⁵), both adsorptions were considered to favor to the direct desulfurization route and the hydrogenation route respectively. Therefore, the HDS process was considered to proceed along the hydrogenation route under microwave irradiation.     

微波-活性炭协同催化降解活性黑5废水的研究

采用微波协同活性炭催化降解活性黑5废水,探讨了活性炭用量、微波辐照功率、活性黑5初始浓度、微波辐照时间对活性黑5去除效果的影响。在活性黑5初始浓度为60 mg/L,活性炭用量为20 g/L,微波辐照时间为20 min,微波辐照功率为480 W的试验条件下,溶液中活性黑5的去除率可高达94.4%。     

湿法炼锌泥的微波干燥实验

目前回转窑干燥物料的方法主要存在干燥时间长、环境污染严重、效率低等缺点,为了解决这一问题,开展了微波干燥湿法炼锌泥的实验研究,采用实验室自制的微波干燥设备,考察微波功率、干燥时间以及物料质量对样品脱水率的影响。研究结果表明:在一定条件下,脱水率随干燥时间延长而增加,随着微波功率的增加而提高,随物料质量增加而降低。实验在微波功率600W、物料质量40g、微波加热时间3min时,湿法炼锌泥的脱水率达到99.57%;FT-IR分析可知,干燥后波数1625cm^-1和3300cm^-1附近水分子的伸缩振动峰基本消失,说明微波干燥后物料基本不含水分;与常规干燥进行比较,微波干燥湿法炼锌泥具有干燥时间短、脱水效率高、清洁无污染的优点,是一种高效节能的新型干燥方法。     

微波辐射对愈创木酚降解的影响

研究将微波辐射用于降解愈创木酚(G-M).通过微波场下的升温行为对比试验得出,活性炭水溶液的升温速率明显高于纯水.通过实验对比了活性炭存在与空白条件下对G-M的降解效果,结果表明单独微波辐射几乎不能降解G-M.考察了G-M初始浓度、微波加热时间、微波辐射强度、活性炭用量对处理效果的影响.基于单因素实验结果,安排正交实验,确定其最优工艺条件.在最佳工艺条件下,处理后的G-M水溶液吸光度为0.312,G-M的去除率可稳定在97.2%左右.     

Deep extractive desulfurization of oil over 12-molibdophosphoric acid encapsulated in metal-organic frameworks

A desulfurization process for model oil and real oil was investigated based on the chemical oxidation of mixed sulfur containing compounds in the presence of nitrogen compounds (indole and quinoline) using hydrogen peroxide as oxidizing agent and dodecamolibdophosphoric acid (H₃PMo₁₂O₄₀) encapsulated in a kind of metal-organic framework (HKUST-1) as PMo@HKUST-1. The effect of isopropanol, ethanol and acetonitrile as extractive solvent and 1-ring (toluene, xylene and mesitylene) and 2-ring (naphthalene) aromatic hydrocarbons in desulfurization of model oil was studied. The desulfurization of sulfur-containing compounds was accelerated in the presence of aromatic hydrocarbons. In fact, a higher desulfurization efficiency of the heterogeneous catalyst could be achieved with system containing a polar solvent in contact with an aromatic hydrocarbon. Quinoline had no effect on oxidative desulfurization (ODS) reaction, whereas indole had a slightly negative effect. Presence of aromatic compounds had slightly positive effect on ODS reaction.     

微波条件下水分含量对淀粉醚化反应的影响

以木薯淀粉为原料,3-氯-2-羟丙基三甲基氯化铵为阳离子醚化剂,自制碱性复合催化剂为醚化催化剂,采用微波法制备阳离子淀粉。研究探讨不同醚化剂用量、不同微波功率、不同微波时间条件下,反应体系水分含量对阳离子醚化反应效率的影响。结果表明,不同的醚化剂用量、不同的微波功率及不同的微波时间组合,获得最佳醚化反应效率所需的反应体系水分含量各有不同。醚化剂用量较高时,选用较高的体系水分含量以及较高的微波功率和较长的微波时间,可获得较高的醚化反应效率;醚化剂用量较低时,选用中等的体系水分含量以及中等的微波功率和较长的微波时间,可获得较高的醚化反应效率。     

体相光催化处理有机废水新工艺

针对工业废水浓度和色度高、光线在废水中的穿透能力有限、催化剂极易中毒等因素,本文以球形微波无极灯为“点光源”填充反应器构建“体光源”,提出体相光催化反应的设想,探索光催化处理工业废水的过程强化作用。分别以甲基橙溶液和含2,4-二氯酸农药废水为研究对象,探索体相光催化反应过程中有机污染物的降解性能;以乙醇水溶液和青霉素废酸水为研究对象,探索体相光催化反应过程热效应与光催化在废水处理中的耦合作用。结果表明,体相光催化反应不仅可以有效地降解水溶液中有机物,2,4-二氯酸农药废水COD_Cr去除率达到83.9%,而且利用反应器运行过程中的热效应能够100%地分离回收青霉素废酸水中的乙酸丁酯,同时去除55.8%的COD_Cr。因此,填充床式体相光催化反应系统能够将微波能、光催化和热效应集成于一体,在实现光催化技术处理有机废水及资源化的实际应用方面有积极意义。