气水两相流动规律实验分析和化学排水方法探讨

本文通过几年来大量的实验分析和现场试验,总结出气水两相在井筒内主要存在气泡流、柱塞流、环膜流、霉状流。不同的流型具有不同的流动规律。本文着重讨论柱塞流和环膜流。并且认为化学排水只适用于这两种流型。

化学排水采气在胜利油气区的应用

胜利油气区浅层气藏在开发中容易出水，化学排水是提高出水气井开发效果的有效措施之一，本文通过对化学排水的排液机理和影响泡沫性能因素的研究分析，得出适用于该方法的气井范围，并经过现场实践，证明该方法具有施工容易、成本低、收效快、不影响日常生产等优点，在胜利油气区有很强的适用性。

Fenton试剂和氧化镁联合处理化学实验室排水

利用Fenton试剂和氧化镁联合处理化学实验室排水,探讨联合处理的最佳工艺条件。结果表明:在pH值为5时,加入15g/L过氧化氢和2g/L硫酸亚铁搅拌反应30min,废水的COD去除率达82.1%,经二级处理后排水中的COD去除率达96.4%;加入15g/L氧化镁后废水中的重金属离子去除率达到99.8%。

无压化学建材排水管道闭气试验技术研究

为提高无压化学建材排水管道严密性检验效率,通过研究我国现状闭水试验和闭气试验优缺点,参照美国材料与试验协会相应标准及大量试验数据论证,提出适合我国的闭气试验标准:规定测试压力为30 000 Pa、允许渗漏率为0.4572×10^(-3)(m^3/min/m^2),并给出压降值为7 000 Pa时不同管径的最小闭气时间。

盐井化学助排水采天然气实践

针对气卤同采的盐井,在生产后期,由于地层压力减小,排水能力减弱,采气量降低的问题,提出化学助排水采气技术措施,提高了气井的采收率。

珠海斗门软土地基电动化学加固效果分析

电动化学排水加固实际上就是在待加固的土层中,插入几对具有一定间距的金属电极,将插入土体的金属电极以一定间距进行打孔作为注浆管或者排水管,并把这对电极接到直流电源上,通过浆液和电渗的双重作用,加速土体加固进程。本文简单介绍了电动化学排水加固在珠海淤泥质土和淤泥中的应用,对珠海淤泥和淤泥质土加固前后原状土土体抗剪强度、含水率、凝聚力、摩擦角进行了数据分析。最终数据表明,电动化学排水加固可有效处理淤泥,淤泥加固后的灵敏度大幅度降低,土体的凝聚力可提高25%左右,摩擦角可提高40%左右。各个区域加固均匀,电动化学排水加固在加固淤泥质土和淤泥方面效果明显。

A coupled strain softening and hardening model for completely weathered granite in a fault zone

his study focused on exploring the specificity of mechanical behavior for completely weathered granite,as a special soil,by consolidated drained triaxial tests.The influences of dry density(1.60,1.70,1.80 and 1.90 g/cm^(3)),confining pressure(100,200,400 and 600 kPa),and moisture content(13.0%,that is,natural moisture content)were investigated in the present work.A newly developed Duncan-Chang model was established based on the experimental data and Duncan-Chang model.The influence of each parameter on the type of the proposed model curve was also evaluated.The experimental results revealed that with varying dry density and confining pressure,the deviatoric stress–strain curves have diversified characteristics including strain-softening,strain-stabilization and strain-hardening.Under high confining pressure condition,specimens with different densities all showed strain-hardening characteristic.Whereas at the low confining pressure levels,specimens with higher densities gradually transform into softening characteristics.Except for individual compression shear failure,the deformation modes of the specimens all showed swelling deformation,and all the damaged specimens maintained good integrity.Through comparing the experiment results,the strain-softening or strain-hardening behavior of CWG specimens could be predicted following the proposed model with high accuracy.Additionally,the proposed model can accurately characterize the key mechanical indicators,such as tangent modulus,peak value and residual strength,which is simple to implement and depends on fewer parameters.

邓关背斜构造卤水伴生低压天然气探讨

阐述了邓关背斜构造,卤水和伴生低压天然气开采的历史与现状。从地质构造、资源等方面进行了挖潜找气可行性的论述。提出了老井挖潜和化学助排水采气,提高天然气采收率的几项措施。

Physico-chemical and elemental investigation of aqueous leaching of high sulfur coal and mine overburden from Ledo coalfield of Northeast India

Acid mine drainage （AMD） is one of the major problems in high sulfur coal mining areas generating acidic water. The acidic mine water generated contain hazardous elements in varying concentrations. The Northeastern Indian coalfield produces considerable amounts of AMD. The AMD and metal leaching from coal and mine over burden （OB） are the two important naturally occurring processes. In order to know the AMD potential, the aqueous leaching experiment of a few coal and OB samples from the Ledo colliery of the Northeastern coalfield, Mergherita （India）, at different time periods （1, 3, 5, and 8 h） and at different temperatures （25, 45, 65, and 90℃） were performed in the laboratory. The physico- chemical analysis of the aqueous leachates shows the pH, electrical conductivity （EC）, and total dissolved solid （TDS） in the range of 1.62-3.52, 106-2006 μs/cm, and 106-1003 ppm for the raw coal samples respectively. The OB samples produced pH, EC, and TDS in the range of 3.68-6.92, 48.6-480 μs/cm, and 69.5-240 ppm respectively. From the study, it was revealed that the concentrations of major （Si, A1, K, Na, Fe, Ca, Mg）, minor （Mn） and trace/hazardous elements （As, Ba, Cd, Co, Cr, Cu, Hg, Ni, Pb, Se, Zn） considerably change with leaching time as well as with leaching temperature. Out of these elements As, Cd, Hg, Pb, Cr, and Se are of greater environmental importance. Alteration of the physico-chemical structure of the coal and OB samples resulting from leaching was also studied by field emission scanning electron microscope- energy-dispersive X-ray spectroscopy method. The release of the potentially hazardous elements from the raw coal and OB during leaching time periods to the leachates was detected by inductively coupled plasma-atomic emission spectroscopy and ion-chromatographic analyses. The major minerals found in coal and OB are quartz （SiO2）, pyrite （FeS2）, hematite, marcasite, and kaolinite. The association of different functional groups in minerals and their mode of association were studied by Fourier-transform infrared spectroscopy and X-ray diffraction analytical techniques. The present laboratory study will be useful in relating the characteristics of aqueous leaching from coal and mine OB with the natural weathering condition at the coal mine area.

THE EFFECT OF DRAINAGE ON CHEMICALELEMENTS CONTENT OF MARSH

This paper takes marsh in the Sanjiang Plain as an example in order to research the effect of draining on the chemical elements in marsh. The Sanjiang Ecological Test Station of Mire and Uetland serves as the resarch base. The authors selected soil samples in the Sanjiang Plain (the top and the end of the drain, marsh soil and degeneration marsh soil), mainly analyzed contents of main ions (HCO 3 ? , Cl?, SO 4 2? and NO 3 ? ), main heavy metals (Fe, Mn, Zn and Cu), nutritive elements (N, P, K), organic matter and pH value. By testing these samples as above, the paper initially researches the effect on chemical elements content by draining by the means of the contrast of chemical elements contents between marsh soil and degenerative marsh soil and different characteristics of marsh soil elements. Results show that a lot of chemical elements had been lost because of draining.

Effects of Self-purification of River Water on Laundry Wastewater

[Objective] This study was conducted to investigate the effect of laundry wastewater on the quality of river water and the dilution purification effect of river water on laundry wastewater. [Method] The effects of laundry wastewater on the contents of total nitrogen(TN), total phosphorus(TP), suspended solids(SS), chemical oxygen demand(COD) and linear alkylbenzene sulfonic acid(LAS) were studied in 7 rivers of Shaoxing City. [Result](1) The contents of TN, TP, SS, COD and LAS increased by 92%, 99%, 340%, 351% and 923%, respectively, at the discharging moment of laundry wastewater; and(2) the five pollutional indexes significantly decreased over time, and especially 2 h after the discharge of laundry wastewater, compared with former the discharge of laundry wastewater, the contents of TN, TP, COD and LAS increased by 6%, 11%, 9% and13%, respectively,while the contents of SS still increased by 76%, i.e., SS required a longer time to achieve self-purification. [Conclusion] Laundry wastewater has some influence on thequality of river water, and the self-purification function of river water could effectively remove pollutants.

Physico-chemical Characteristics of a Gold Mining Tailings Dam Wastewater

The study was conducted on the status of the quality of wastewater from the tailings dam of Central Africa Gold Limited in Bibiani, Ghana, to ascertain the level of contamination of the wastewater. The tailings dam stores process effluent from the gold extraction plant. Wastewater samples taken from the tailings dam were analyzed for physico-chemical characteristics. Arsenic, iron and cyanide were identified as the major pollutants in the tailings dam wastewater with average concentrations of 4.5, 25.2 and 11.1 mg.L1, respectively. Arsenic, iron and free CN （cyanide） concentrations in the process effluent exceeded the Ghana EPA discharge limits of 0.2, 2 and 0.2 mg.Ll, respectively. High conductivity, total dissolved solids, sulphate and ammonium were found in the wastewater studied. The tailings dam serves as a natural reservoir that removes most of the total suspended solids and the turbidity, resulting in the improvement in the aesthetic appeal of the wastewater. Nonetheless, arsenic, iron and cyanide concentrations were still high and hence the wastewater cannot be discharged into the environment without prior treatment.

Factors Impacting Water Quality of a Small Stream in a Mountain Forest

Recent improvements to sewerage systems have meant that the relative contribution of point sources of pollution to the overall pollutant loads of streams has decreased markedly. Consequently, the potential increase in non-point source pollution means that it may be necessary to focus more on pollution loads from non-point sources in the future. This study examined pollution loads from non-point sources in streams flowing through forested areas. In addition, the relationship between runoff and pollution loads was also clarified. The small streams in the Tohoku University Botanical Gardens, in Sendai city, Japan, were sampled during a dry weather period and their water quality parameters were characterized. Chemical Oxygen Demand （COD） concentration increased with distance downstream, possibly because the soils in downstream areas contained high amounts of organic matter. Conversely, the concentration of nitrate nitrogen （NO3-N） decreased with distance downstream, probably because upstream soils were generally in an oxidized state while those further downstream were reduced. COD concentration increased with air temperature, while NO3-N levels decreased with an increase in air temperatures.

Pretreatment of highly turbid coal mine drainage by a chemical agent free filtration system

A filtration system used without chemical agents for the pretreatment of turbid coal mine drainage is described in this paper.The influence of different aperture sizes and different motor speeds was investigated during the study.The experimental results show that for aperture diameters of 0.4,0.6,or 0.8 mm smaller apertures provide more complete filtration.Rotations of 12,20,28,or 40 r/min show that higher speeds give more efficient filtration.Suspended solids decreased in both particle size and concentration after the filtration.The separated slime can be directly reused as a fuel.Efficient filtration pretreatment systems for coal mine drainage were investigated and the economic feasibility is analyzed in this article.

Experimental Research on Coke Wastewater Treatment by Hybrid Biological Reactor

Phase hybrid biological reactor （HBR） was used in treating coke wastewater by adding submerging fiber-ball fillers in suspended growth activated sludge. The optimum operation parameters for the highest performance were determined. It was found that the hybrid biological reactor worked well for the coke wastewater treatment in terms of Chemical Oxygen Demand （COD）, NH4＋ -N and other refractory organic compounds removal efficiencies. Compared with conventional activated sludge system, the removal rate of COD and NH4＋ -N and the nitrating rate were higher and more stable in the hybrid biological reactor. COD of effluent was less than 75 mg/L and the removal rate of COD and NH4＋ -N could be up to 95.0% and 92.5% when COD of influent and NH4＋ -N were less than 700 mg/L and 300 rag/L, respectively. In this way, the quality of effluent concentration could reach the first class of integrated wastewater discharge standard （GB8978-1996） （COD ≤100 mg/L）.

Biocatalytic desymmetrization of 3-substituted glutaronitriles by nitrilases. A convenient chemoenzymatic access to optically active (S)-Pregabalin and (R)-Baclofen

Desymmetrization of prochiral 3-substituted glutaronitriles offers a new approach to access （S）-Pregabalin and （R）-Baclofen. A number of nitrilases from diverse sources were screened with 3-isobutylglutaronitriles （1a） or 3-（4＇-chlorophenyl）glutaronitriles （1b） as the substrate. Some nitrilases were found to catalyze the desymmetric hydrolysis of la and lb to form optically active 3-（cyanomethyl）-5-methylhexanoic acid （2a） and 3-（4＇-chlorophenyl）-4-cyanobutanoic acid （2b） with high enantiomeric excesse （ee）, respectively. This cannot be achieved using traditional chemical hydrolysis. Among them, AtNIT3 generated （R）-2b whereas BjNIT6402 and HsN1T produced the opposite （S）-enantiomer with high conversions and ee values. Not only the nitrilases showed different activities and stereoselectivities toward these 3-substituted glutaronitriles, the 3-substitueut of the substrates also exerted great effect on the enzyme activity and stereoselectivity. （S）-2a and （S）-2b were prepared with high yields and ee values using BjNIT6402 and HsNIT as the biocatalysts, respectively. A straightforward Curtius rearrangement of （S）-2a and （S）-2b, followed by the acidic hydrolysis, afforded （S）-Pregabalin and （R）-Baclofen. This offers a new platform methodology for the synthesis of optically active β-substituted T-amino acids of pharmaceutical importance.