新型橡胶除臭剂破解环保难题

橡胶制品的生产过程中会产生一些有毒有害气体和水,它们大多数都是硫化氢、二氧化硫、有机胺和苯类污染物。河北任县泰斗合成材料厂日前新近研制的9328-L型橡胶环保系列除臭剂可去除硫化氢、二氧化硫等气体,可使胺及苯类污染物的排放为零,净化率为100％,处理后的外排废水各项性能指标均达到国家标准,对人畜均无害,可循环使用,实现清洁生产。     

脉冲电晕放电处理低浓度硫化氢气体

采用线一筒式脉冲电晕反应器对硫化氢气体进行去除,考察了影响硫化氢去除率的主要参数。当气体的停留时间为17s、硫化氢的初始质量浓度约为100mg／m^3、峰值电压为48kV时,对硫化氢的去除率接近96％,且增加峰值电压、气体停留时间或气体中的氧气含量可提高硫化氢的去除率。对放电作用下硫化氢的去除动力学进行了研究,并对硫化氢的分解产物进行了初步分析。     

采用Na2S或NariS处理废水中锌离子的试验探讨

对粘胶纤维生产中处理硫化氢气体产生的硫化钠与硫氢化钠用于废水中锌离子的去除进行了试验探讨,通过在酸性和中性两种条件下的试验对比,得出这两种产物不同的锌离子去除率。在中性条件下硫化钠和硫氢化钠对锌离子有很高的去除率,在酸性条件下硫化钠对锌篱子去除效果不受影响,但硫氢化钠对锌离子去除率明显下降。     

焦化废水处理研究

用TiO2光催化氧化法和混凝沉降法分别对经生化处理的焦化废水进行了实验研究。研究表明，在光催化氧化法中，CODcr去除率最高可达55．4％，浊度的去除率最大为40．9％，用矿渣复合混凝剂对其进行混凝沉降实验，由水渣和硫铁矿渣分别用硫酸和盐酸搅拌浸取制得1#、2#和3#、4#混凝剂，4#对焦化废水CODcr去除率和浊度的去除率相对1#、2#、3#是最好的，分别达到了36．7％和70．8％；而1#和2#混凝剂，其脱色效果最好。     

使用泥炭土作为深床过滤的过滤介质进行含油废水的处理

本文所进行的研究是对泥炭土过滤器用于含油排放水处理性能的评估。泥炭土过滤床能够有效地去除含油废水中的污染物，去除率大于99％，按COD计算污染物去除率为70％。滤液中绝大多数COD含量是由泥炭土水解产生的木质纤维化合物和腐殖酸引起的，此时显示出比初始乳液更高的生物可降解性。     

多孔TiO2陶瓷光催化剂降解糠醛废水

以钛酸四丁酯等为原料，采用简单工艺制得多孔TiO2陶瓷光催化剂；并研究了利用多孔TiO2陶瓷光催化降解糠醛废水。结果表明，在紫外灯下照射60min，糖醛废水的COD去除率可达59．8％，而通入空气有利于污染物的去除。     

赤泥处理含磷废水的研究

研究了赤泥投加量、反应时间、pH值和搅拌速度对含磷废水去除效果的影响,探讨了赤泥煅烧活化前后对废水中磷的去除作用。结果表明,700℃下高温煅烧2h可以将赤泥对磷的去除率提高34．1．％。当反应时间为120min、pH=7、搅拌转速为200r·min^-1、进水磷浓度为10mg·L^-1时,按每毫克磷投加4．07g煅烧赤泥,磷去除率可达到89．4％。对赤泥吸附废水中磷实验数据进行回归分析,符合Freundlich吸附等温式。     

离子交换纤维法去除碱性废水中硫氰酸根的研究

研究了离子交换纤维去除碱性废水中SCN-的可能性,考察了纤维用量、反应时间、初始pH、温度等因素对废水中SCN-去除率的影响,并研究了SCN-的交换等温线。结果表明,强碱性离子交换纤维可有效实现对碱性废水中SCN-的去除,其最佳条件是:反应时间为5 min,反应初始pH为8～11,温度为30℃,在此条件下,SCN-的去除率可达99.5%左右。离子交换纤维去除碱性废水中SCN-的过程受温度影响较大,且满足Boyd液膜扩散公式和Freundlish等温式。     

冰箱、冷库用高效液体除臭剂

为解决冷藏设备的除臭和保持食品新鲜,国内目前大多用固体活性炭吸附除臭剂,效果差。杭州市化工研究所试制成高效液体除臭剂,对氨、三甲胺、硫化氢等气体吸收     

Fenton氧化去除榨菜生产废水COD

研究了Fenton氧化处理技术对榨菜废水COD去除的可行性,考察了反应时间、初始pH、初始Fe（Ⅱ）浓度及H2O2用量等因素对榨菜生产废水COD去除率的影响。结果表明,Fenton氧化技术可以有效实现对榨菜废水COD的去除,其最佳条件是：反应时间为120．0min,反应初始pH为3．0,c0（Fe（Ⅱ））=50．0mmol·L^-1,c0（H2O2）=16．7mg·L^-1,在此条件下,榨菜废水COD去除率可达76．0％;当H2O2投加总量不变时,改变过氧化氢的投加方式,去除率随着投加次数的增多而增大,四次投加时,COD的去除率达到82．2％。     

超重力湿式氧化法脱除焦炉煤气中硫化氢

以H2S、CO2和空气模拟焦炉煤气,以超重机为脱硫设备,采用湿式氧化法脱除焦炉煤气中的H2S,研究了超重力因子、液气比、气液接触时间、原料气中H2S含量等工艺参数对脱硫率的影响规律,结果表明：脱硫效率随着超重力因子、液气比、气液接触时间和原料气中H2S浓度的增大而增大。确定了适宜的工艺参数,在气液接触时间为0.15 s的条件下,获得了98%以上的脱硫效率,CO2的脱除率稳定在1.0%左右,超重力法脱硫技术实现了高效、快速脱硫。在生产现场建成了处理气量为10000 m3/h的工程化超重力湿式氧化法脱硫装置,运行结果显示：超重力湿式氧化法脱除焦炉煤气中H2S技术具有脱硫效率高、气液接触时间短、操作弹性大、设备体积小等优点,H2S脱除率可稳定在90%以上,应用前景广阔。     

介质阻挡放电等离子体脱除沼气中硫化氢的实验研究

介质阻挡放电（DBD）等离子体技术是一种有效的气体污染物控制技术。开展了利用DBD等离子体技术脱除模拟沼气中硫化氢的实验研究,考察了放电能量密度、硫化氢初始体积浓度、停留时间以及含氧量对硫化氢脱除效果的影响,并分析了DBD等离子体反应器中脱除硫化氢的产物。结果表明,DBD等离子体能有效脱除模拟沼气中的硫化氢气体,脱除效率随放电能量密度、停留时间和含氧量的增大而提高,并且随硫化氢初始体积浓度的增加而下降;当模拟沼气处理气量为382mL／min、硫化氢初始体积浓度为4000×10^-6、氧气体积浓度为2％、能量密度为24．1kJ／L时,硫化氢气体被完全脱除,同时氧气的体积含量也低于0．5％,达到了国家规定的车用天然气标准内的硫化氢和氧气含量标准。根据产物分析,硫化氢的脱除产物主要为二氧化硫,少量的单质硫粉。     

Removal of hydrogen sulfide in a three phase fluidized bed bioreactor

To remove hydrogen sulfide biologically, a three phase fluidized bed bioreactor was used in whichThiobacillus sp.IW was immobilized on biosands. The optimum operating condition of the bioreactor was found to be 30 ‡C, pH 7, bed height of 0.85–1.0 m and aspect ratio of 1.0. At these conditions, the bioreactor removed more than 88 % of the hydrogen sulfide for an inlet concentration of 30–160 ppm and a gas flow rate of 2–5 Z/m. The maximum removal rate obtained was about 1,000 mg H₂S/min. In continuous operation of the bioreactor, the removal efficiency remained at 99 % for up to 16 hours and decreased to 91 % at 52 hours.     

活性炭的改性条件及其对硫化氢吸附性能的影响

以工业活性炭为载体制备改性活性炭,对比研究了未改性活性炭,NaOH、Na2CO3、Fe(NO3)3、Cu(Ac)2改性活性炭及挂膜硫氧化细菌后活性炭在相同条件下对硫化氢穿透时间及吸附容量的影响。结果表明：在相同控制条件下,NaOH改性活性炭明显优于其它改性剂;不同梯度改性剂条件下,20% NaOH改性活性炭对硫化氢的吸附效果最好,吸附穿透容量为78.25 mg/g,穿透时间可以达到2000 min以上;不同改性剂挂膜硫氧化细菌后对硫化氢均有一定的处理效果,其中对已达到饱和吸附的NaOH改性活性炭挂膜后的再生效果可以达到100%以上,说明挂膜硫氧化细菌活性炭对硫化氢的处理具有很好的效果。     

Oxidative absorption of hydrogen sulfide using an iron‐chelate based process: chelate degradation

BACKGROUND: Oxidative absorption of hydrogen sulfide into a solution of ferric chelates is studied in a stirred cell glass reactor. The experiments were performed to investigate the degradation of chelates sodium salt of nitrilotriacetic acid (NTA) (Merck), ethylenediaminetetraacetic acid diadisodium salt (EDTA) and diethylenetriaminepentaacetic acid (DTPA) at 313 K, pH 6, iron concentration 10 000 g L^?1 and Fe:chelate molar ratio 1:2. RESULTS: Oxidative absorption of hydrogen sulfide into a solution of Fe‐NTA was found to be more successful, therefore, further experiments with 10%, 50% and 100% concentrations of hydrogen sulfide were performed. It was shown that this process is applicable for removal of low and high concentrations of hydrogen sulfide. The effect of antioxidants using sodium thiosulfate was also studied in order to minimize degradation of NTA. The kinetics were studied and it was observed that the reaction appeared to be first order in ferric chelate with rate constants for 100, 50 and 10% hydrogen sulfide concentration: 0.035, 0.013 and 0.019 h^?1, respectively. CONCLUSIONS: Gas sweetening processes have commercial importance in natural gases, refinery of gases and biogas processing. Desulphurization and cleaning (i.e. removal of H₂S and CO₂) of petroleum gas and biogas is important to make the gas methane rich and to increase the calorific value of fuel. The same techniques of desulphurization and cleaning can be used for treating natural gas or petroleum gas. The desulphurization and cleaning processes can minimize the atmospheric emission of gases like SOx, NOx and CO. As the iron chelate based process is based on the principle of redox reaction of metal chelate with hydrogen sulfide, this method is very useful for desulphurization of petroleum gas and biogas. This work studied the effective use of Fe‐NTA solution for removal of high to low concentrations of H₂S as found in biogas and industrial waste gases. © 2012 Society of Chemical Industry     

接种辫硫杆菌与活性污泥生物滴滤塔去除硫化氢效果对比

为了解决恶臭污染问题,采用接种辫硫杆菌ZG11的生物滴滤塔A与接种活性污泥的生物滴滤塔B对硫化氢气体进行了4个多月的脱臭实验研究,主要考察了进气浓度、冲击负荷和氮利用率对硫化氢去除率的影响以及实验前后压力损失的变化。结果表明：当硫化氢进气浓度低于600 mg/m3,即进气负荷Nv低于113.33 g/(m3?h)时,滴滤塔A的去除率接近100%。当进气浓度低于750 mg/m3,即Nv低于133.33 g/(m3?h)时,滴滤塔B的去除率接近100%。当进气流量为8 m3/h时,滴滤塔A与B的压力损失分别为176.4 Pa/m和313.6 Pa/m。与滴滤塔A相比,滴滤塔B启动快,去除速率高,抗冲击负荷能力强,但压力损失大,受氮源的影响较大。     

还原-氧化-石灰法处理氯代硝基苯废水的研究

研究了硫化钠还原、Fenton试剂氧化、石灰脱色综合方法处理氯代硝基苯酸性废水。考察了溶液pH值及硫化钠、双氧水、硫酸亚铁、石灰用量等因素对CODCr去除率的影响。结果表明,用该方法处理氯代硝基苯酸性废水,CODCr去除率可达到94%以上。     

Simultaneous Absorption of H2S and Co2 Into Aqueous Methyldiethanolamine

Abstract

The tertiary araine methyldiethanolamine (MDEA) is finding increasing application as a chemical solvent for selective absorption of hydrogen sulfide from gases containing hydrogen sulfide and carbon dioxide. Gas streams of this type include some natural gases, synthetic gases from coal and heavy oil gasification and tail gases from sulfur plants. Selectivity for H2S is needed either to enrich Glaus sulfur plant feed in H2S or to remove only H₂S when CO₂ removal is not necessary or economic. For the absorption of hydrogen sulfide into MDEA, the reaction which occurs can be considered to be instantaneous while carbon dioxide undergoes a second-order reaction with MDEA.

In this work, the simultaneous absorption of two gases into a liquid containing a reactant with which both gases react is modelled using the film theory. Physical properties and kinetic rate parameters used in the model have been measured in our laboratory. The model is used to study the effect of process variables on the selectivity of MDEA for H₂S over C0₂. The simultaneous absorption of H₂S and CO₂ gases into aqueous MDEA is studied experimentally using a continuous stirred tank absorber. Experimental absorption rates are compared to predictions based on a multicomponent mass transfer model. The average deviations of the theoretical calculations from the experimental results are 10.2% and 12.9% for C0₂ and H₂S, respectively.     

固定化氧化亚铁硫杆菌处理硫化氢新工艺研究

用单一的生物反应器处理硫化氢时,微生物容易受到硫化氢的毒害作用而使细胞活力受损,废气处理效率迅速降低。为此,提出生物和化学二级反应器处理硫化氢的新工艺,并对微生物的生长、分布、最适工艺运行条件和影响因素等做了研究。结果表明,生物反应器中微生物对亚铁离子的氧化速率对硫化氢的去除效果有着重要的影响,二级反应器工艺大大提高了硫化氢去除效率,反应的主要产物为单质硫,同时便于对硫沉淀的分离,在操作温度31℃,pH值1.5—1.8,水力停留时间2.5 h,进气质量浓度8 g/m3,硫化氢承载负荷2 000 g/(m3.h)以下时,系统可以稳定运行,硫化氢的脱除率可达99%以上。     

Low Temperature Catalytic Decomposition of Hydrogen Sulfide into Hydrogen and Diatomic Gaseous Sulfur

A new catalytic reaction of hydrogen sulfide decomposition is discovered, the reaction occurs on metal catalysts in gas phase according to equation $$2{\text{H}}_{2} {\text{S}} \leftrightarrow 2{\text{H}}_{2} + {\text{S}}_{2}^{{({\text{gas}})}}$$ 2 H 2 S ? 2 H 2 + S 2 ( gas ) to produce hydrogen and gaseous diatomic sulfur, conversion of hydrogen sulfide at room temperature is close to 15 %. The thermodynamic driving force of the reaction is the formation of the chemical sulfur–sulfur bond between two hydrogen sulfide molecules adsorbed on two adjacent metal atoms in the key surface intermediate and elimination of hydrogen into gas phase. “Fingerprints” of diatomic sulfur adsorbed on the solid surfaces and dissolved in different solvents are studied. In closed vessels in adsorbed or dissolved states, this molecule is stable for a long period of time (weeks). A possible electronic structure of diatomic gaseous sulfur in the singlet state is considered. According to DFT/CASSCF calculations, energy of the singlet state of S₂ molecule is over the triplet ground state energy for 10.4/14.4 kcal/mol. Some properties of gaseous diatomic sulfur are also investigated. Catalytic solid systems, both bulk and supported on porous carriers, are developed. When hydrogen sulfide is passing through the solid catalyst immersed in liquid solvent which is capable of dissolving sulfur generated, conversion of hydrogen sulfide at room temperature achieves 100 %, producing hydrogen in gas phase. This gives grounds to consider hydrogen sulfide as inexhaustible potential source of hydrogen—a very valuable chemical reagent and environmentally friendly energy product.