炼厂火炬气螺杆压缩机腔体硫结晶分析

介绍了长庆石化公司火炬气螺杆压缩机机腔结硫的成因,分析其机理,认为高硫化氢气体和富氧环境是导致结硫的主要因素,提出改进措施。

基于氨法脱硫结晶的影响因素与举措控制分析

本文从当前基于氨法脱硫结晶的发展情况与现实需要出发,针对其中存在的缺陷与问题以及重要的影响因素进行了细致的分析与研究,并针对如何控制这些影响因素以及解决现实存在的缺陷与问题提出了具有科学性与可行性的解决意见与发展策略,有利于不断提升氨法脱硫结晶的生产效率与质量,不断促进其发展进步。

饱和器法硫铵结晶生成、生长原理研究

针对焦化厂生产的硫铵粒度小、质量差的现状 ,通过对饱和器硫铵结晶生成、生长的化学动力学研究 ,找到结晶生成、生长的影响因素 ,从而为化工厂生产提供最佳化设计和指导 ,解决硫铵晶粒过小的问题。

脱硫新工艺——结晶硫法(CrystaSulf^(SM))

介绍了一种能够直接在高压下处理中低潜硫量含硫气的脱硫新工艺。其脱硫溶剂为一种非水溶性的混合有机溶液 ,对硫磺具有高溶解性 ,且沸点高。该工艺的特点是溶液循环量低、硫容高(9.32g/l)、H2 S脱除率高、无发泡和硫堵问题、化学品消耗低、硫磺产品粒度大且纯度高。分别比较了胺/克劳斯 /TGT、液相氧化还原和结晶硫工艺处理高压含硫气以及克劳斯尾气的经济性。

氨法脱硫超低排放改造中影响硫氨结晶因素探讨

针对某煤化工燃煤锅炉超低排放改造后出现的硫氨结晶品质差原因进行了简要探讨,并提出了初步建议。

硫铵结晶器的优化设计

以某厂硫铵结晶器的设计为例,介绍了硫铵结晶器结构上的优化设计,包括圆筒形折流挡板的优化、导流筒的优化、刚性环耳式支座的优化以及采用底搅拌器等。优化的设备运行良好。

硫铵溶液酸度在线检测控制方法

焦化生产工艺过程中,硫铵工段结晶槽酸度检测是通过人工取样来进行分析,费时费力,且检测不及时,不能很好地对生产工艺过程进行实时把控。本文通过研究硫铵结晶槽酸度全自动测量控制方法,自动取样、分析、检测酸度值,实现硫铵槽酸度稳定控制、降低硫酸消耗、提高硫铵产量、节省人力、成本低、提高全过程可靠程度。溶液和滴定剂反应后的产物以及清洗水都可以排入样品罐中,不会对样品罐内的样品产生影响,不用单独处理废液。

氨法在烧结烟气脱硫中的应用

在钢铁工业排放的污染物中,烧结烟气中的二氧化硫和焦化废氨水等都是难以处理的污染物。利用焦化废氨水吸收烧结烟气中SO2的氨-硫铵工艺具有脱硫率高、运行可靠、投资低、副产品可以回收等优点,在脱硫的同时也去除了焦化废水中的氨污染,是一种以废治废、有应用前景的新方法。本文介绍了采用焦化废氨水吸收烧结烟气中的SO2的治污方法原理,并对其工艺流程、特点及运行费用等作了分析。

Synthesis,crystal structures,and antibacterial activities of two zinc(Ⅱ) complexes bearing 5⁃phenyl⁃1H⁃pyrazole group

A novel compound(H_(2)L)SCN(5⁃methyl⁃3⁃phenyl⁃2H⁃pyrazol⁃1⁃ium thiocyanate)has been obtained by the reaction of thiosemicarbazide with benzoylacetone in ethanol.Two zinccomplexes[Zn(HL)_(2)(NCS)(CH_(3)COO)](1)and[Zn_(2)(L)_(2)(HL)_(2)(NCS)_(2)]_(2)·2CH_(3)OH(2)have been synthesized by the coordination reactions of Zn(OAc)_(2)·2H_(2)O or ZnCl_(2)with(H_(2)L)SCN under reflux conditions.Elemental analyses and single⁃crystal X⁃ray diffraction have con⁃firmed the structures of the synthesized compounds.The(H_(2)L)SCN ligand and complex 1 pertain to the triclinic sys⁃tem with space group P1,while complex 2 belongs to the monoclinic system with space group P2_(1)/n.Additionally,the antibacterial activities of the compounds were evaluated in vitro using the agar diffusion method against the bac⁃terial strains(Candida albicans,Staphylococcus aureus,and Escherichia coli).The results showed that the ligand exhibited relatively good antibacterial activities against the bacteria,and the complexes possessed stronger antibac⁃terial activities against the same bacteria than the free ligand.CCDC:2190252,(H2L)SCN;2190253,1;2190256,2.

锅炉烟气脱硫脱硝系统运行问题及处理措施

甲醇厂CFB锅炉烟气脱硫脱硝系统改造投运后,脱硫系统出现硫酸铵浆液结晶差、脱硫塔循环喷头堵塞、液氨消耗大、硫酸铵输送玻璃钢管线断裂频繁等问题,SNCR脱硝系统出现了氨水浓度低、NOX指标不合格等问题。以上问题经过技术攻关和设备改造,逐步予以解决并优化了脱硫脱硝运行工况。

Cyanide-free silver electroplating process in thiosulfate bath and microstructure analysis of Ag coatings

Cyanide-free silver electroplating was conducted in thiosulfate baths containing AgNO3 and AgBr major salts, respectively. The effects of major salt content and current density on surface quality, deposition rate and microhardness of Ag coatings were investigated. The optimized electroplating parameters were established. The adhesion strength of Ag coating on Cu substrate was evaluated and the grain size of Ag coating was measured under optimized electroplating parameters. The optimized AgNO3 content is 40 g/L with current density of 0.25 A/dm2. The deposited bright, smooth, and well adhered Ag coating had nanocrystalline grains with mean size of 35 nm. The optimized AgBr content was 30 g/L with current density of 0.20 A/dm2. The resultant Ag coating had nanocrystalline grains with mean size of 55 nm. Compared with the bath containing AgBr main salt, the bath containing AgNO3 main salt had a wider current density range, and corresponding Ag coating had a higher microhardness and a smaller grain size.

Solubility Model of Thiamine Nitrate During Recrystallization Process

The concentration variations of all key components were investigated during recrystallization process of thiamine nitrate, and a mathematic model that is used to show the solubility variations of thiamine nitrate was constructed in this paper. Comparing the predicted values with those experimental results, it was concluded that the model well reflected the solubility variations of thiamine nitrate during recrystallization process. The proposed model was important to study the nucleation process and crystal growth process during recrystallization process, and also provided a beneficial method to study the solubility variations of solute during such precipita- tion process.

卧式反应釜在湿法制砷工艺中的应用研究

卧式釜连续加压浸出工艺目前多用于湿法炼锌、湿法炼钴等行业,在湿法制砷行业比较先进的是立式釜加压浸出工艺,还没有卧式釜连续加压浸出应用于湿法制砷领域。因此贵冶采用试验的方式对卧式釜连续加压浸出应用于湿法制砷进行了研究,并对进液量、风量等参数进行了研究,摸索出了最佳工艺条件,成功地将卧式釜新工艺应用于湿法制砷,非常具有推广价值。

Alterations of FHIT Gene and P16 Gene in Nickel Transformed Human Bronchial Epithelial Cells

Objective To study the alterations of FHIT gene and P16 gene in malignant transformed human bronchial epithelial cells induced by crystalline nickel sulfide using an immortal human bronchial epithelial cell line, and to explore the molecular mechanism of nickel carcinogenesis. Methods 16HBE cells were treated 6 times with different concentrations of NiS in vitro, and the degree of malignant transformation was determined by assaying the anchorage-independent growth and tumorigenicity. Malignant transformed cells and tumorigenic cells were examined for alterations of FHIT gene and P16 gene using RT-PCR, DNA sequencing, silver staining PCR-SSCP and Western blotting. Results NiS-treated cells exhibited overlapping growth. Compared wkh that of negative control cells, soft agar colony formation efficiency of NiS-treated cells showed significant increases （P〈0.01） and dose-dependent effects. NiS-treated cells could form tumors in nude mice, and a squamous cell carcinoma was confirmed by histopathological examination. No mutation of exon 2 and exons 2-3, no abnormal expression in pl6 gene and mutation of FHIT exons 5-8 and exons 1-4 or exons 5-9 were observed in transformed cells and tumorigenic cells. However, aberrant transcripts or loss of expression of the FHIT gene and Fhit protein was observed in transformed cells and tumorigenic cells. One of the aberrant transcripts in the FHIT gene was confirmed to have a deletion of exon 6, exon 7, exon 8, and an insertion of a 36 bp sequence replacing exon 6-8. Conclusions The FHIT gene rather than the P16 gene, plays a definite role in nickel carcinogenesis. Alterations of the FHIT gene induced by crystalline NiS may be a molecular event associated with carcinogen, chromosome fragile site instability and cell malignant transformation. FHIT may be an important target gene activated by nickel and other exotic carcinogens.

Separation and recovery of Ni from copper electrolyte by crystallization of nickel ammonium sulfate double salt

The separation and recovery of Ni from the copper electrolyte by crystallization of nickel ammonium sulfate double salt were studied.It is found that the solubility of copper sulfate at the same temperature is less than that of nickel sulfate,while the solubility of copper ammonium sulfate is greater than that of nickel ammonium sulfate.So,by adding(NH_(4))_(2)SO_(4),the Ni can be selectively crystallized from the copper electrolyte.By adding(NH_(4))_(2)SO_(4)at the molar ratio of(NH_(4))_(2)SO_(4)/NiSO_(4)≤0.8,and crystallizing at−15℃for 10 h,the Ni in the copper electrolyte can be crystallized in the form of Ni(NH_(4))_(2)(SO_(4))_(2)×6H_(2)O.The qualified product of NiSO_(4)×6H_(2)O can be obtained by pyrolyzing the crystals,dissolving the pyrolysis product in water,and then concentrating the dissolved solution for crystallization.The method of double salt crystallization is a clean,environmentally-friendly,cost-effective and efficient method for separating and recovering nickel from copper electrolyte.

Transformation behavior of ferrous sulfate during hematite precipitation for iron removal

The transformation behavior of ferrous sulfate was examined during hematite precipitation for iron removal in hydrometallurgical zinc.Specifically,the effects of the method used for oxygen supply(pre-crystallization or pre-oxidation of ferrous sulfate)and temperature(170–190℃)on the redissolution and oxidation–hydrolysis of ferrous sulfate were studied.The precipitation characteristics and phase characterization of the hematite product were investigated.The results showed that the solubility of ferrous sulfate was considerably lower at elevated temperatures.The dissolution behavior of ferrous sulfate crystals was influenced by both the concentrations of free acid and zinc sulfate and the oxydrolysis of ferrous ions.Rapid oxydrolysis of ferrous ions may serve as the dissolution driving force.Hematite precipitation proceeded via the following sequential steps:crystallization,redissolution,oxidation,and precipitation of ferrous sulfate.The dissolution of ferrous sulfate was slow,which helped to maintain a low supersaturation environment,thereby affording the production of high-grade hematite.

氨精制装置运行问题分析及改造措施

通过分析中国石油兰州石化分公司炼油厂氨精制装置存在的运行问题，提出了相应的改造措施，包括在分凝器脱液管线上新增隔离阀门、更换三级冷凝冷却器、更换氨压缩机及采用低温结晶脱硫工艺等。改造后装置运行结果表明：三级分凝器出口温度由70℃降至小于35℃，压缩机吸气量由5m^3／min提高至74m^3／min，原料酸性水中硫化氢质量分数下降45．5％，氨质量分数下降55．5％，净化水合格率达100％，氨精制塔塔顶温度下降5-20℃，液氨中氨质量分数由97．05％上升至99．60％，液氨产量达0．125t／h，实现了装置的长周期运行。

Syntheses and Crystal Structures of Molybdenum-Sulfur Clusters Mo_3S_4 (dtp)_3(o-CH_3OC_6H_4COO)(Py) and Mo_3S(dtp)_3(p-HOC_6H_4COO)(DMF)·EtOH

The title compounds Mo3S4(dtp)3(o-CH3OC6H4COO)(Py) 1 and Mo3S(dtp)3(p-HOC6H4COO)(DMF)稥tOH 2 (dtp = diethyldithiophosphate) were synthesized by thereactions of Mo3S4(dtp)4(CH3CN) and Mo3S4(dtp)3(CH2ClCOO)(Py) with o-methoxylbenzoic acid and p-hydroxybenzoic acid, respectively. Their crystal structures were determined by X-ray diffraction analysis. The crystal data for compound 1: Mo3S10P3C25H42O9N, monoclinic P21/n, Mr = 1201.93, Z = 4, a = 14.164(1), b = 23.065(2), c = 14.732(1) ? = 109.677(1) ? V = 4532(1) ?, D= 1.762 gcm-3, = 1.428 mm-1, F (000) = 2408, R = 0.0739, wR = 0.1528 for 3552 observed reflections (I > 2); and for compound 2: Mo3S10P3C24H48O11N, triclinic P ? Mr = 1227.96, Z = 2, = 10.2098(3), b = 14.3333(4), c = 18.1711(5) ? = 94.694(1), = 102.166(1), = 110.665(1) , V = 2396.5(1)3, Dc = 1.638 gcm-3, = 1.350mm-1, F (000) = 1184, R = 0.0445, wR = 0.1281 for 6597 observed reflections (I > 2). Intermolecular S…S interactions are observed between the molecules of compound 1 while intramolecular O…HC and intermolecular S…HC hydrogen bondings are found in the crystal packing diagram of compound 2.

Reactive Crystallization of Calcium Sulfate Dihydrate from Acidic Wastewater and Lime

The present work focused on the recycle of the sulfate and the metal ions from acidic wastewater dis charged by nonferrous metallurgical industry. The effects of the temperature, the reactant concentration, the stirring speed and the metal ions on the reactive crystallization process of calcium sulfate between sulfuric acid and lime were systematically investigated. The morphology of the precipitated crystals evolved from plateletlike and nee dlelike shape to rodlike shape when the temperature was increased from 25 to 70 ℃. An increase in the agglom.

Kinetics analysis of Ni-TiO_2 composite system during initial stages of electro-crystallization

The initial stage of Ni-TiO2 composite system electrodeposition on glassy carbon electrode from an acidic solution of nickel sulfate was investigated using cyclic voltammetry （CV）, chronoamperometry （CA） and electrochemical impedance spectroscopy （EIS）. Analysis of current density-time transients was performed using the nonlinear fitting procedure and electrochemical impedance spectroscopy was simulated by Z-view software. Besides, the surface morphology of Ni-TiO2 co-deposition at the initial stage was observed by scanning electron microscopy （SEM）. The results show that, in the case of low overpotential （-790 mV vs SCE）, the presence of TiO2 particles in the plating bath makes the nucleation relaxation time tm^x decreased clearly. Meanwhile, the electro-crystallization of Ni-TiO2 system follows a Scharifker-Hills （SH） progressive nucleation/growth mechanism. While in the case of higher overpotential, the presence of the TiO2 particles in solution makes the nucleation relaxation time tmax increased. At -850 mV （vs SCE）, the co-deposition of Ni-TiO2 system meets SH instantaneous nucleation/growth mechanism. The results of impedance spectra show that the appearance of the characteristic inductive loops represents the nucleation/growth of nickel and the presence of TiO2 particles reduces the charge transfer resistance of solution. The SEM observation confirms that TiO2 particles can be considered as favorable sites for nickel nucleating.