从铅锌尾矿中回收重晶石的应用研究

对青海某铅锌尾矿中重晶石进行了综合回收,通过对该尾矿矿石性质分析,进行了重选及浮选-重选联合工艺方案的试验研究.通过这两种工艺流程对比,最终决定采用浮选-重选联合工艺流程处理该铅锌尾矿,通过试验获得了BaSO4品位为90.18%,回收率为52.45%的重晶石精矿,有效回收了尾矿中的重晶石,为企业创造了显著的经济效益.     

Marine Water Quality Assessment Of Synthetic-Based Drilling Waste Discharges

Drilling muds or fluids used in drilling operations serve several functions: they lubricate the drill bit; maintain borehole pressure; clean and condition the hole; and flush rock cuttings to the surface. Drilling mud also adheres to rock cuttings, as can formation oil. Barite is used as a weighting agent, which approximately makes up approximately 33% of synthetic mud. It contains traces of heavy metals, which contribute to the toxicity of drilling waste. As environmental issues attract increasing public awareness, the treatment and disposal of spent drilling fluids and contaminated rock cuttings from drilling operations have become sensitive issues for offshore operations around the world. Within the last decade, the oil and gas industry has introduced synthetic-based drilling fluids as substitutes for oil-based fluids. This pollution prevention measure has been complemented by improvements in solid control systems technology. This paper adopts the current U.S. Environmental Protection Agency methodology for a hypothetical case study of an oil field on the East Coast of Canada to determine the water quality impacts of disposal of drilling wastes. The concentration of pollutants at the edge of the mixing zone in the water column and pore water are estimated and compared with Canadian water quality guidelines for protection of aquatic life.     

Determination of radiation attenuation coefficients of heavyweight- and normal-weight concretes containing colemanite and barite for 0.663 MeV γ-rays

Accurate measurements have been made to determine radiation transmission of concretes produced with barite, colemanite and normal aggregate by using beam transmission method for 0.663 MeV γ-rays energy of ¹³⁷Cs radioactive isotopes by using NaI(Tl) scintillation detector. Linear and mass attenuation coefficients of thirteen heavy- and four normal-weight concretes were calculated. It was determined that the linear attenuation coefficient (μ, cm⁻¹) decreased with colemanite concentration and increased with barite concentration in both type of the concretes. Mass attenuation coefficient values of our concretes were compared with the values proposed by the United States National Institute of Standards and Technology (NIST).     

Heavy metals contribution of non-aqueous fluids used in offshore oil drilling

A monitoring program was performed to investigate heavy metal content alteration due to exploratory drilling for oil using non-aqueous fluids (NAFs) in Brazilian offshore, 900 m deep. Fourteen elements were monitored in 54 sites and it was verified that after drilling activities the average Ba concentration was remarkably increased with respect to background level, even 1 year after the activity. A minor increase in Mn and a moderate increase in Al concentrations were verified. The Cd, Cr, Ni, As, Co, Cu, Pb, V, and Zn concentrations were at the background levels, ca. 1 year after the NAFs drilling materials deposition on the seafloor. The Al, Ba, Cd, Cr, Cu, Ni and Zn mean concentrations were significantly different (P<0.05) between the three sampling operations (cruises) performed, while As, Cd, Fe and Pb presented different mean values according to the distance of the oil well, independent of the sampling operation. Interaction between sampling operation and distance was observed for Mn. In all sediment samples the Hg concentration was below the detection limit (0.07 μg g⁻¹).     

络合法去除油田硫酸钡的研究与应用

以二乙烯三胺五乙酸（DTPA）为螯合剂主剂,配以氢氧化钾中和至pH值为13,并添加一定量的无机盐,对重晶石粉末进行溶出研究。结果表明,在DTPA质量分数一定的情况下,由于溶液黏度影响,钾盐的助溶效果为钠盐的2倍;随着无机盐质量分数的增加,碳酸钾、氟化钾和氯化钾对重晶石的助溶效果相应增加,碳酸钾添加量为10%时,溶出率达到最高的47.79%;反应4 h时,由于重晶石结块导致反应面积增大,碳酸钾的助溶效果比氟化钾高10.56%;反应12 h时,反应趋于完全,由于盐效应影响反应终点,氟化钾的助溶效果比碳酸钾高12.39%;对DTPABa3-离子进行了计算机模拟,得到了其稳定构象,并分析了钡离子络合常数低的原因;最终将该螯合剂应用于某堵塞油井,并对返排液中的无机盐组分、硫酸盐沉淀组分进行了XRD分析,并在沉淀中检测出钡元素,证明油井解堵成功,应用良好。      

Simulations of mass attenuation coefficients for shielding materials using the MCNP-X code

In this paper,mass attenuation coefficients of concrete,bricks and cement plaster,as shielding materials,are calculated at 59.5,356,662,1173,1274 and 1333 keV by using the MCNP-X (version 2.4.0) code.The numerical simulation results are compared with previous Monte Carlo studies,experimental results and XCOM data.The effects of barite on mass attenuation coefficients are investigated.The mass attenuation coefficients increase with the barite content.Thus,our results agree well with experimental studies on gamma ray shielding of barite.It is flexible for the MN method to change the barite rates in material by small increments,which is experimentally difficult.Also,modeled geometry can be used for future approaches such as new designs and new structures especially in investigating new barite-containing materials to build nuclear reactors or high-energy radiation therapy facilities.     

中国重晶石供需形势及出口前景

重晶石主要用于油气钻井行业,其需求量与油气资源的勘查和开发密切相关。我国是世界上最大的重晶石储量国和最大的生产国,然而由于每年大量的出口造成了我国重晶石资源的过度开发和浪费,如何保护我国这一重要优势矿产的优势地位是目前迫切需要解决的问题。本文在把握全球重晶石资源形势的基础上,对我国重晶石的资源、供需及贸易现状进行了简要的分析,指出随着海洋、非常规及境外油气的开发,需求量将平稳增加,重晶石价格也将逐渐上升,我国需要确立相关的法规和制度来保护这种优势矿产。通过本文的分析可以明确我国重晶石资源面临的问题以及未来的形势,以期为我国制定相关法律法规来规范市场、保护资源,以及相关行业形成组织协会来参与市场定价等提供科学依据和理论支撑。     

ICP-AES法测定重晶石中的有害重金属

提出简单而快速的同时溶解和测定重晶石中有害重金属元素的方法。使用王水低温溶解重晶石,经过滤取滤液,采用ICP-AES法测定重晶石中的有害重金属(汞,砷,铅,镉,铋等),方法的加标回收率为91.3%~103.0%,RSD为0.58%~2.16%。该方法在重晶石商品的常规检验方面具有一定的实际意义。     

活化重晶石可改善重泥浆的流动性和动力稳定性

研究了活化重晶石在阴离子聚合物钻井液中的粘度效应和动力稳定性。实验发现,活化重晶石明显改善了阴离子聚合物钻井液的流动性,并且有抑制增稠效应,但活化重晶石加重钻井液的滤失量较高。     

超细碳酸钙粒度测定方法研究—液体密度计法

建立了定量测定超细CaCO_3粒度分布简便易行的标准方法,即使用ST-01型沉降粒度计的液体密度计法。讨论了沉降分析的原理、公式来源和影响因素。测定了14个典型样品,最大平行差不超过2％。分析结果与英国MALVERN和法国CILAS激光粒度计的结果一致。沉降分析的精密度和准确度均符合要求,操作简便易行。此仪器还可用来测定重晶石中小于6μm颗粒的含量,分析结果与API标准等效。