蒸发双效料液的自控与报警

一、概况烧碱的蒸发过程,需要消耗大量的能源,故对蒸发过程的进出料液进行自动控制是对稳定生产、降低汽耗、提高碱液质量有很重要的作用。我厂蒸发工段设计能力为年产万吨烧碱,现为年产五千吨烧碱,属于小型氯碱厂。采用的是二效三体顺流式蒸发,即Ⅰ效为两只蒸发器,Ⅱ效为一只蒸发器。二、工艺流程来自电解工段10%左右的电解液经电解液贮槽后,用加料泵打入螺旋式预热器,预热至100℃左右,由循环泵打循环。加料时打入Ⅰ_a 效和Ⅰ_b 效将淡碱浓缩至20%左右后用泵将半成品打入Ⅱ效蒸发器内,Ⅱ效蒸发器     

烧碱蒸发节能降耗

烧碱蒸发节能降耗我厂用隔膜法生产烧碱，其生产能力为５０００ｔ／ａ。蒸发工序选用两台标准型蒸发器，蒸发器加热面积分别为９６ｍ￣２、６７ｍ￣２。蒸汽流程为：Ⅰ效蒸发器冷凝水经疏水器进效前预热器，然后到电解预热淡碱液，再送盐水洗涤盐泥。Ⅰ效二次汽进Ⅱ效加热...     

烧碱蒸发过料控制系统应用

1　工艺状况介绍烧碱是我厂的主导产品 ,在整个生产结构中占有很大的比例 ,烧碱生产的正常与否直接影响着我厂的经济效益 ,而蒸发工序的运行状况不仅直接影响烧碱的质量 ,而且影响着氯产品或其他联产品的生产和经营。在原蒸发工序中采用传统的目视过料出料法 ,检测手段落后 ,造成许多环节故障频繁 ,工人劳动强度也较大 ,严重制约着我厂的生产经营。为达到装置的高效运行 ,在蒸发改造中我们遵循高起点、新技术、少投资、高收益的原则 ,结合我厂实际 ,自行设计了我厂蒸发过料出料的自动控制系统。蒸发Ⅰ效顺流 ,Ⅱ、Ⅲ效强制循环工艺是一个传…     

Ⅱ效蒸发器结盐的原因及处理措施

Ⅱ效蒸发器结盐的原因及处理措施李法曾郑德兴（寿光氯碱厂２６２７０９）１概述１９９６年我厂完成烧碱扩建工程，烧碱年生产能力达到２．５万ｔ。在蒸发的扩建改造中，我们将Ⅰ、Ⅱ、Ⅲ效蒸发器的换热面积进行了增大，采用三效四体顺流工艺生产烧碱，浓效利用Ⅰ效冷凝水...     

电容式物位计在碱蒸发器上的应用

我厂是50年代建设的老氯碱企业,其主要产品烧碱的生产规模为离子膜碱2万t/a、隔膜碱4万t/a。在隔膜碱的蒸发工序中采用的是三效顺流蒸发工艺,多年来4个蒸发效体的液位测量问题一直困扰我们,搞过多次技改,也走过不少弯路。1997年底我们试用了德国E H公司生产的智能型电容式物位测量仪表,并采用该公司具有抗冷凝抗物料粘结功能的探杆,获得满意效果。     

几种密封在碱泵上的应用

一、碱泵密封问题的提出我厂烧碱蒸发工艺是采用三效三体顺流蒸发。生蒸汽的压力为7～8Kg/cm~2,第Ⅰ效蒸发器内的液面压力为3.5Kg/cm~2,碱液浓度为12～18％,温度150℃。由于液面压力高,碱液可以顺流地从第Ⅰ效过到第Ⅱ效蒸发器,因此对第Ⅰ效过第Ⅱ效的循环用泵的性能要求不高。第Ⅱ效蒸发器内的液面压力为0.5～1Kg/cm~2,碱液浓度由18％上升到22％,温度120℃。此时盐的结晶大量析出,碱液中含盐的结晶颗粒>14％,再加之蒸发器和管路等的保温厚度不够,泵体及     

三效逆流升膜蒸发装置运行总结

介绍了离子膜法烧碱三效逆流升膜蒸发工艺流程及其优点,对试车期间存在的蒸汽压力不稳定、Ⅰ效产出的碱液不合格及仪表等设备质量差的问题提出了解决措施.     

交流5．国产降膜蒸发二效降膜管能否使用镍材质

A：各位专家，国产降膜蒸发Ⅱ效降膜管有用镍材质的吗？ B：双效降膜蒸发Ⅱ效降膜管国产的有部分厂家使用了镍材质，不过厂家不是特别多。     

国产降膜蒸发二效降膜管能否使用镍材质

正A:各位专家,国产降膜蒸发Ⅱ效降膜管有用镍材质的吗?B:双效降膜蒸发Ⅱ效降膜管国产的有部分厂家使用了镍材质,不过厂家不是特别多。A:你好!我的问题是三效蒸发中的Ⅱ效降膜管使用的材质情况。B:三效蒸发中的Ⅱ效降膜管使用镍材质的国产装置也有,是主流。A:有使用国产镍材的吗?B:有啊,有很多厂家采用。A:都是哪些厂家使用国产的降膜管?能提供厂家吗?     

离子膜烧碱蒸发工艺技术的确定

通过对离子膜烧碱液采用膜式蒸发浓缩制取低浓度固碱的三种工艺流程（即两效顺流、两效逆流和单效两段蒸发流程）的物料，热量衡算和分析比较，推荐在有条件的氯碱厂似采用两效逆流蒸发工艺流程较为合理。     

Reclamation of nickel from spent nickel catalyst

Spent nickel catalyst containing an average 9.6% nickel was obtained locally from an oil hydrogenation industry. It was digested with 1–3N HCl, HNO₃, H₂SO₄ and mixtures thereof in one to three stages of durations ranging from one to three hr at 100°C using spent nickel catalyst to acid proportions of 1:3 to 1:8 (w/v). Nickel recoveries of over 94% were obtained when one part of spent catalyst was digested for three hr with six or more parts of 3N mixture of HCl and HNO₃ (3:1, v/v). Acid extracts of spent nickel catalyst obtained using HCl, H₂SO₄ and mixtures thereof were treated with NaOCl to convert their content of iron in the ferric form. The iron from the nickel extract was precipitated out in the form of ferric hydroxide at pH 6.0. Nickel from the iron-freed acid extracts was recovered at pH 8.5±0.5 as nickel hydroxide. Nickel formate was prepared by refluxing nickel hydroxide with 10% formic acid in about 6% excess to stoichiometric requirements for 30 min. The dried nickel formate was reduced in peanut oil at 230°C to 270°C for 0.25 to 2.75 hr. The reduction at 260°C on kieselguhr support, employing nickel formate:oil:support in ratio of 50:43:7, for two hr provided catalyst of maximum activity. The hydrogenation activity of the reclaimed catalyst, assessed by standard AOCS procedure, was greater than that of the parent catalyst. Presented at the AOCS Meeting in New Orleans, LA, in May 1987.     

Quasi-static compression behavior of nickel oxide,nickel oxide:zirconia,nickel:zirconia and nickel foams

An effective material for use in shock mitigation should spread the deflection of the shock wave over a longer period of time and should minimize the force felt by the object under impact. Ductile or brittle cellular materials are currently gaining importance due to their unique high energy absorption characteristics. Reticulated cellular foam structures of nickel oxide (NiO) and nickel oxide:zirconia (NiO:YSZ 60:40 percentage by wt.) were fabricated by polymeric sponge replication process. These foams are reduced under hydrogen atmosphere to produce metallic nickel (Ni) and nickel:zirconia (Ni:YSZ) cermet foams, respectively. X-ray diffraction studies on the struts confirmed the corresponding phase formation. Further, the volume fraction of the solid in foam is estimated through image analysis. All the foams are subjected to uni-axial compression and the stress–strain curves were recorded. A comparative evaluation of progressive deformation behavior at room temperature was also carried out. Stress–strain curve of the nickel foam shows distinctly three regimes under compression, a deformation regime showing a linear dependence in the strain with stress. This is followed by a second region showing a plateau corresponding to the energy absorption resulting from the permanent plastic deformation while retaining the integrity and finally densification region through the wall collapse resulting in the maximum compressive strength. Stress–strain curves of all other foams such as NiO, NiO:YSZ and Ni:YSZ has demonstrated a similar fracture behavior under compression which caused not only by unstable crack propagation originating from a single crack, but also by merging of many cracks leading to the formation of the crushed zone. Compressive strength is found to be a strong function of solid fraction supporting the load and percentage porosity of NiO foams. Estimation of relative energy absorption has exhibited higher energy absorption irrespective of the material of construction at higher strain rates.     

Electrochemical recovery of nickel from nickel sulfamate plating effluents

Nickel sulfamate solutions are widely used for industrial nickel plating, when electrodeposits with low stress are required. Partial decomposition of sulfamate with decreasing pH below ca. 2.5 degrades the properties of nickel electrodeposits, decreases the charge yield and results in spent solutions, from which nickel must be recovered before they could be discharged to sewers. Results are reported of charge yields for nickel recovery from an industrial sulfamate effluent, using an electrochemical reactor operated at constant current in batch-recycle mode and incorporating a nickel mesh cathode, a Ti/Ta₂O₅–IrO₂ mesh anode and a cation-permeable membrane to prevent anodic oxidation of sulfamate. A micro-kinetic model was developed, treating the processes of nickel(II) and proton reduction in sulfamate solutions as two multi-step reactions involving adsorbed intermediates, Ni_ads^I and H_ads, respectively. The unknown kinetic parameters were obtained using gPROMS software by iterative fitting of the model to experimental data obtained over a range of nickel(II) concentrations and bulk solution pH, enabling evaluation of nickel(II) reduction charge yields as a function of nickel(II) concentration, bulk pH and electrode potential. A model combining the micro-kinetic equations with mass and charge balances on the reactor was used to determine the control parameters for electrochemical recovery of elemental metal from nickel(II) in batch-recycle mode. It was determined experimentally that a decrease in catholyte pH to values below ca. 2.5 resulted in a decrease in nickel(II) reduction charge yields to values below 0.9. The decrease in catholyte pH, caused by the flux of protons from the anolyte where they were generated via anodic oxygen evolution, was obviated by continuous addition of NaOH at a rate determined by the model, permitting nickel(II) recovery with an average charge yield of 0.94.     

Supported nickel catalyst from hydroxycarbonate of nickel and aluminium

The hydroxycarbonate of nickel and aluminium (Ni/ Al = 3) with a hydrotalcite-like structure is an outstanding precursor of the active component of supported nickel catalysts. Good mechanical strength and suitable nickel content of these catalysts, which are necessary for practical applications, can be achieved by mechanical mixing of this compound with an additional support. The catalyst prepared from a mixture of 56.5 wt-% of nickel-aluminium hydroxycarbonate and 43.5 wt-% of γ-alumina was proven to have a stable catalytic activity in the methanation reaction at 2 MPa and 800 K.     

球形镍氧化物制备硫酸镍的方法研究

以球形镍氧化物为原料,研究了制备高纯硫酸镍的方法。首先借助X射线衍射仪（XRD）和X射线光电子能谱仪（XPS）对球形镍氧化物的主要成分进行表征,确认其主要成分为氧化镍;其次对球形镍氧化物浸取制备较高纯度的硫酸镍条件进行了优化,确立了硫酸浓度为1.84 mol/L、反应温度为200 ℃、固液比为0.3 g/mL、反应时间为6 h为最优反应条件;最后利用高温条件下（250 ℃）获得的一水合硫酸镍固体,提出了将其再次溶解生产pH和镍浓度可控的高纯硫酸镍溶液的方法。     

"节镍、代镍"技术

由于镍价的飙升,镀镍成本大幅上升、为了减少镍的用量,电镀行业十分重视对节镍、代镍电镀工艺的研究。简要介绍了已开发的多层镍电镀工艺、铜锡合金、铜锌合金、锌铁合金、镍铁合金等代镍工艺,以及厚(薄)铜薄镖电镀工艺。     

Study of the properties of nickel oxide and nickel as precursors for the tartaric acid-NaBr-modified nickel catalyst

Nickel oxide was prepared by the decomposition of nickel hydroxide and then the nickel oxide was reduced to form the nickel catalyst. The properties of the nickel oxide and the reduced nickel were studied in relation to the enantio-differentiating ability (e.d.a.) of a tartaric acid-NaBr-modified reduced nickel catalyst. The modified nickel catalyst prepared from nickel oxide with less non-stoichiometric oxygen produced a high e.d.a. for the hydrogenation of methyl acetoacetate. The high crystallinity of the nickel oxide and the resultant nickel would be required to attain a high e.d.a.     

Hydrothermally synthesised nickel oxide nanostructures on nickel foam and nickel foil for supercapacitor application

Nickle-based oxides exhibit seamless redox activity and show undisputed parameter optimization flexibility, which makes them a candidate of choice for various scientific analysis and multipurpose execution. The communique addresses the domain of energy storage of hydrothermally fabricated nickel oxide nanostructures by analysing the capacitive behaviour of the sample. The crystal geometry, chemical composition and bonding state of the material were carried out through XRD and XPS analysis, respectively. Electron microscopy showed systematically aligned nano-needles, which in aggregate represent an urchin. A comparative study of specific capacitance (Cs) at a scan rate of 1 mVs^?1 showed an enhanced Cs of nickel oxide embedded Ni-foam (1125 Fg^-1) against nickel oxide deposited Ni-foil (454 Fg^-1). At a current density of 8 mAcm ^?2, the nickel oxide based Ni-foam electrode exhibited an energy density of 23 Whkg^?1 and a power density of 259 Wkg^-1 which makes it instrumental in electrochemical devices. The Ni-foam electrode also showed less ‘cycle fatigue’ as its charge/discharge stability dipped by just 12% even after 5000 cycles. The novel supercapacitor electrode developed in this study exhibits excellent specific capacitance, high stability, high power density, and low impedance, demonstrating its promising practical functionality.     

Pulse reversal plating of nickel and nickel alloys for microgalvanics

The use of pulse reversal (PR) plating, as an alternative to the use of additives for electrochemical deposition of nickel, is studied. With optimised pulse plating parameters, and in some cases in combination with additives, substantial improvement of the deposit properties can be achieved. Utilising chloride-type baths, PR plating of pure nickel (and harder nickel–cobalt alloys) have been used to fabricate tools for micro-injection moulding (Polymer Structures for μTas, EuroSensors, Copenhagen, 27–30 August, 2000) and micromechanical structures. Furthermore, preliminary results from pulse plating experiments with ternary magnetic alloys, comprising 50–60% Co, 25–35% Fe and 10–20% Ni, will be reported. For both pure nickel and nickel alloys good chemically stable electrolytes have been developed, and the deposits are smooth with low residual stress. None of the electrolytes contain sulphur co-depositing additives (such as saccharin) nor wetting agents.     

从含镍磷铁中提镍的初步研究

以蛇纹石为原料生产钙镁磷肥副产含镍磷铁。为了提取含镍磷铁中的镍同时综合回收磷和铁,采用氨浸法以及酸浸法进行多种工艺组合实验。结果表明,含镍磷铁加纯碱经过850℃灼烧2 h后,水浸分离磷酸三钠,滤渣再加氨水在50℃浸取4 h,可以提取50%的镍;用硫酸处理含镍磷铁,可以一步生成硫酸镍和磷酸并进入溶液中,与铁分离,再经过过滤、沉淀、结晶等操作,最后分离出碳酸镍、磷酸氢二钠及氢氧化铁。