石油化工可燃气体或蒸气排放系统的消防安全设计

石油化工生产装置大多是通过火炬燃烧排放易燃易爆气体或通过放空管将易爆气体直接排入大气中。文章分析了火炬系统和放空管的火灾危险因素,并从火炬的布置、高度、排放能力、自动监控装置以及放空管的气体排放浓度、安装位置、安全装置等方面,重点论述了火炬系统和放空管的消防安全设计要点。     

Optimal size,hydraulic retention time and volatile solids loading rate of biogas unit using water hyacinth

With a view to evaluate the effects of hydraulic retention time and volatile solids loading rate on methane production using water hyacinth, experiments were conducted in a 160 dm³ capacity, well-mixed continuous digestion unit at ambient temperature. The optimal design of biogas plant using water hyacinth was elucidated, to provide a unit giving a maximum methane yield of 0.16 nm³ kg^?1 volatile solids added, which was 60% greater than the conventional plant using cowdung. The calculations of optimal design factors were based on reactor size, hydraulic retention time and volatile solids loading rate; considerations were made of capital cost, running costs and operational revenue.     

Advances in Microporous and Mesoporous Solids—Highlights of Recent Progress

This report highlights developments in the fields of microporous and mesoporous materials that were published mostly during the year 2002. Selected examples are provided to illustrate new zeolite structures, porous coordination materials, mesoporous solids with new compositions, controlled morphologies, and increased hydrothermal and thermal stabilities, as well as porous solids with tunable pore openings or other structural features that can be dynamically modified. A number of applications are discussed, including stabilization of reactive guests, separations, electronic materials, and sensors.     

Solids Extraction of Cod Frame and Effects on Ultrafiltration of the Aqueous Extract

Grinding, pH adjustment, heat treatment and centrifugation were studied to recover solids from ground cod frames and to apply ultrafiltration (UF) to the resulting aqueous phase. Early heat treatment (90°C/20 min) dissolved collagen into aqueous phase resulting in a very low UF flux. A pH adjustment to 4.5 after grinding (～0.32 cm die), with no heat resulted in efficient separation after centrifuging. UF of the aqueous phase showed an increase in initial flux (23 L/hr m²). However, when the same aqueous material was heated and then centrifuged (1–2% solids removed), UF flux was further increased to 46 L/hr m²and this process gave highest solids recovery (90%).     

Gravity pipe flow of polymeric bulk solids in pneumatic conveying system

Various physical parameters of gravity pipes such as gravity pipe diameter, the inclination of the gravity pipe, the cone angle, temperature of the discharged material and the rate of air counter flow into the gravity pipe were studied. The results obtained from the pipe diameter and cone angle experiments showed that the mass flow rate was proportional to (D-1.4d)^2.5 and also to θ^-0.5. The results from the pipe inclination experiment showed the existence of an angle of inclination for maximum flow, which was also reported by Wieghardt [Uber einige versuche an stromungen in sand. Ingenieur Archived 20, 109-115]. The air flow experiment also showed that the mass flow rate was inversely proportional to the air counter-flow rate, and strongly influenced by the material properties. Results from the temperature experiment showed that the temperature of the material had slight effect on the mass flow rate for the temperature range that was used in the experiment. Flow visualization images showed formation of solid plugs in the pipe that played a part in influencing the behaviour and mass flow rate of solids in the system.     

Influence of the surface conditions on permeation in the deuterium–MANET system

The condition of the surfaces is of crucial importance for the deuterium permeation through materials. In this work a study of the surface constants for the adsorption (σk₁) and release (σk₂) of deuterium under different surface conditions on the martensitic steel DIN 1.4914 (MANET) has been carried out. The growth of an oxide surface layer (Cr₂O₃) of about 25–30 nm in a MANET sample, heat treated in an oxidizing environment, compared to the bare MANET that have a ‘natural' oxide of about 5 nm has provoked a reduction of both the permeation rate and the recombination coefficient (about 3 orders of magnitude). In addition, the permeation governing process has changed from diffusion-limited to surface-limited. The measurements of the permeation rate of deuterium were performed by a gas-phase permeation technique over the temperature range 574–746 K and for deuterium driving pressures in the range from 3 to 10⁵ Pa.     

中国第一口超千米深水钻井液技术

LW3-1-1探井位于中国南海珠江口盆地，作业水深1480m，完钻井深为3843m，地层以大套灰色泥岩和页岩为主，具有强水敏性．要求钻井液具有良好的流变性、润滑性、抑制性，良好的抗盐、抗钙、抗高温和抗低温能力，以及强的天然气水合物抑制能力。该井采用了PFMX钻井液体系，钻井周期为49d，介绍了钻井液工艺及现场应用情况。PFMX体系表现出很多油基钻井液的优点，如好的润滑性、高的钻进速率、膜效应、强的井眼稳定及页岩抑制性，解决了强水敏性地层的井壁稳定等问题，还解决了深水钻井中遇到的挑战，如低的破裂压力梯度、天然气永合物、浅层水流、深水低温等问题，满足了该区块作业需要。     

Characterization of CuInS2 thin films for solar cells prepared by spray pyrolysis

We have made a study of the chemical composition, the electrical, the optical and the structural properties of polycrystalline CuInS₂ thin films prepared by spray pyrolysis to be used for thin film solar cells. These films were deposited starting from aqueous solutions with different chemical compositions ([Cu]/[In] and [S]/[Cu] ratios) and at different substrate temperatures. In all cases, the material is p-type with grains preferentially oriented in the (112) direction of the sphalerite structure. The electro-optical properties show a very strong dependence on the [Cu]/[In] ratio in the solution. Films with copper excess have smaller resistivity and better crystallinity than those which are stoichiometric or have indium excess. The results obtained in this work show the possibility of having CuInS₂ thin films with a wide range of resistivity, a fact that could be important for making solar cells based on this material.     

Void formation and growth in a class of compressible solids

A new class of compressible elastic solids, which includes the Blatz-Ko material as a special case, is proposed. A closed-form solution is constructed and studied for a bifurcation problem modeling void formation in this class of compressible elastic solids. The relation between the void-formation condition and the material parameters is obtained analytically. An energy comparison of the void-formation deformation and the homogeneous expansion deformation is carried out.     

上行气固两相流充分发展段的摩擦压降

为确定气固提升管充分发展段的摩擦压降及其对颗粒浓度测试的影响,提出了充分发展段内气固两相流与管壁间摩擦压力降的计算模型,由此获得充分发展段内真实颗粒浓度的计算公式;同时在两套提升管实验装置上对压力梯度分布和局部颗粒浓度进行了系统测试和对比分析。结果表明,用压差法测试颗粒浓度时摩擦的影响不可忽略,尤其是在气速较高(Ug＞8 m/s）时,表观浓度比实际浓度高出30%～50%;采用建立的模型对表观浓度进行修正,获得的预测值与实际颗粒浓度吻合良好。