浅谈高压中速磨粉系统在磷酸二铵生产中的应用

通过对磷酸二铵生产造粒特性分析,高压中速磨粉机原理分析,结合实践生产中的工艺需求,利用高压中速磨粉系统将颗粒状不合格品磨成细粉后添加进系统重新喷浆造粒,提高返料添加量,减少不合格品的产生,腾空仓库有限货位,以获取更大的经济价值。     

细粒尾矿综合利用技术研究

姑山矿业公司为提高细粒尾矿的综合利用率，研究分析了细粒尾矿的性质，系统研究了尾矿含量、煅烧工艺制度对不同成分体系尾矿陶粒堆积密度、表观密度、空隙率、吸水率、筒压强度及软化系数的影响。研究得出了全尾矿陶粒、细粒尾矿+污泥陶粒、细粒尾矿+污泥+粉煤灰陶粒3种成分体系的尾矿陶粒较优的尾矿含量及煅烧工艺制度，且3种尾矿陶粒均可代替石头用作粗集料。     

松河井田多煤层资源开发条件及合采储层伤害特征

为了降低煤层气井排采过程中的储层伤害,通过分析松河井田的资源开发条件及煤层气井排采数据,总结各排采阶段不合理排采控制引起的储层伤害特征,提出不同排采阶段合理的排采工艺对策。分析结果表明:松河井田煤层气资源丰度达到2.09×10^8m^3/km^2,煤层气资源开发条件较好;松河井田多煤层合层排采过程中,不合理排采控制工艺对煤层气井的产气量影响较大;排采初期以速敏伤害为主,排采中期以气锁和应力闭合伤害为主;修井作业及停抽期间,气锁效应及应力闭合对煤层造成伤害的可能性增大。合理的排采控制能够有效降低煤层气井的储层伤害,提高煤层气井产气量。     

A first-principles investigation on mechanical and metallic properties of titanium carbides under pressure

The titanium carbides are potential candidates to achieve both high hardness and refractory property. We carried out a structural search for titanium carbides at three pressures of 0 GPa, 30 GPa and 50 GPa. A phase diagram of the Ti-C system at 0 K was obtained by elucidating formation enthalpies as a function of compositions, and their mechanical and metallic properties of titanium carbides were investigated systematically. We also discussed the relation of titanium concentration to the both mechanical and metallic properties of titanium carbides. It has been found that the average valence electron density and tractility improved at higher concentrations of titanium, while the degree of covalent bonding directionality decreased. To this effect, the hardness of titanium carbide decreases as the content of titanium increases. Our results indicated that the titanium content significantly affected the metallic properties of the Ti-C system.     

A New Design Methodology for Time-Based Capacitance-to-Digital Converters (T-CDCs)

This paper introduces a 9-bit time-based capacitance-to-digital converter (T-CDC). This T-CDC adopts a new design methodology for parasitic cancellation with a simple calibration technique. In T-CDCs, the input sensor capacitance is first converted into a delay pulse using a capacitance-to-time converter (CTC) circuit; then this delay signal is converted into a digital code through a time-to-digital converter (TDC) circuit. A prototype of the proposed T-CDC is implemented in UMC 0.13 μm CMOS technology. This T-CDC consumes 8.42 μW and achieves a maximum SNR of 45.14 dB with a conversion time of 1 μs that corresponds to a figure of merit (FoM) of 16.4 fJ/Conv.     

The control of paracetamol particle size and surface morphology through crystallisation in a spray dryer

The parameters governing the crystallisation of paracetamol using various conventional techniques has been extensively studied, however the factors influencing the drug crystallisation using spray drying is not as well understood. The aim of this work was to investigate the crystallisation of an active pharmaceutical ingredient through evaporative crystallisation using a spray dryer to study the physicochemical properties of the drug and to use semi-empirical equations to gain insight into the morphology and particle size of the dried powder. Paracetamol solutions were spray dried at various inlet temperatures ranging from 60 °C to 120 °C and also from a series of inlet feed solvent compositions ranging from 50/50% v/v ethanol/water to 100% ethanol and solid-state characterisation was done. The size and morphology of the dried materials were altered with a change in spray drying parameters, with an increase in inlet temperature leading to an increase in particle Sauter mean diameter (from 3.0 to 4.4 µm) and a decrease in the particle size with an increase in ethanol concentration in the feed (from 4.6 to 4.4 µm) as a result of changes in particle density and atomised droplet size. The morphology of the dried particles consisted of agglomerates of individual crystallites bound together into larger semi-spherical agglomerates with a higher tendency for particles having crystalline ridges to form at higher ethanol concentrations of the feed.     

二层沟槽织构对机床导轨表面润滑特性的影响

通过构建二层沟槽织构模型，仿真研究沟槽织构表面的流体动力效应。结果表明：沟槽容积相同时，与单层沟槽相比，二层沟槽的平均油膜压力可以达到单层沟槽的2.31倍；保持二层沟槽的量纲一总深度[β]1、第一层沟槽量纲一宽度[α]1不变时，随着第二层量纲一深度[β]2的增大，平均油膜压力先增大后减小，[β]2为4.4时，平均油膜压力达到最大值；第二层沟槽的量纲一宽度[α]2从0.25增大到0.45时，沟槽内的旋涡区也随之增大，平均油膜压力逐渐减小。     

井下安全阀力学性能分析

井下安全阀对安全性和可靠性要求较高。以渤海油田常用油管携带式井下安全阀为分析对象,对其工作压力、地面控制压力、全开启和全关闭压力、最大下入深度和自平衡能力等关键力学性能进行分析。井下安全阀的工作压力值与地面液控压力值相等,其选取依据为井口压力; 全开启和全关闭液控压力值可通过压力曲线法得到; 最大下入深度取决于弹簧安装时的预紧力; 自平衡能力与活塞面积和自平衡孔面积的比值有关,比值越大,自平衡能力越强。     

抽油井不压井作业装置及抽油泵底阀设计

江苏油田的部分油井存在油管短路、地层高压低渗、漏失严重等问题,这些问题造成压井作业困难,并且压井作业过程中的井控与环境污染风险较大。为了进行不压井检泵作业,同时缩短检泵之后的产量恢复周期,进行了不压井作业技术研究,并研制了不压井作业装置。为解决起下抽油杆过程中的防喷问题,改进了抽油泵底阀结构,该结构可实现起下抽油杆过程中油管不带压、无溢流,并保障起下油管过程中的井控安全。该技术在江苏油田现场应用9井次,效果良好。