Comparison of the mechanisms of microwave roasting and conventional roasting and of their effects on vanadium extraction from stone coal

Experiments comparing microwave blank roasting and conventional blank roasting for typical vanadium-bearing stone coal from Hubei Province in central China, in which vanadium is present in muscovite, were conducted to investigate the effects of roasting tempera- ture, roasting time, H2SO4 concentration, and leaching time on vanadium extraction. The results show that the vanadium leaching efficiency is 84% when the sample is roasted at 800℃ for 30 min by microwave irradiation and the H2SO4 concentration, liquid/solid ratio, leaching temperature, and leaching time are set as 20vo1%, 1.5：1 mL.g-1, 95℃, and 8 h, respectively. However, the vanadium leaching efficiency achieved for the sample subjected to conventional roasting at 900℃ for 60 min is just 71% under the same leaching conditions. Scanning electron microscopy （SEM） analysis shows that the microwave roasted samples contain more cracks and that the particles are more porous compared to the conventionally roasted samples. According to the results of X-ray diffraction （XRD） and Fourier-transform infrared （FTIR） analyses, neither of these roasting methods could completely destroy the mica lattice structure under the experimental conditions; however, both methods deformed the muscovite structure and facilitated the leaching process. Comparing with conventional roasting, microwave roasting causes a greater deformation of the mineral structure at a lower temperature for a shorter roasting time.

Efficacy and safety of endoscopic papillary balloon dilation for the removal of bile duct stones: Data from a “real-life” multicenter study on Dilation-Assisted Stone Extraction

AIM To report data on Dilation-Assisted Stone Extraction(DASE) use in clinical practice and its efficacy and safety trough three Italian referral centers for biliopancreatic diseases treatment. METHODS From January 2011 to December 2015 we collected data on 120 patients treated with DASE. Technical success was obtained when the endoscopist was able to place the balloon trough the papilla inflating the balloon until the final diameter for an adequate time(at least 30 s). Clinical success was obtained after complete stone removal(no remaining stones were visible at the cholangiogram).RESULTS Forty-nine male(40.8%) and 71 female(59%) were enrolled. The mean age was 67.8 years ± 15.7. The mean common bile duct(CBD) dilation was 19.2 mm± 3.9 and the mean size of stones 15.8 ± 2.9. DASE was applied as first approach in 38%(62% after initial failure of stones extraction). Technical and clinical success was of 91% and 87% respectively. In those in which DASE failed alternative treatment were adopted. After DASE 18% of patients experienced a complication(bleeding 9%, pancreatitis 8%, perforation 0.8%). At univariable analysis, elective endoscopic retrograde cholangiopancreatography(P = 0.031), DASE as first approach(P = 0.032), and cannulation of major papilla followed by guidewire insertion(P = 0.004) were related to low risk of complications. Pre-cut was related to an increased risk of complications(P = 0.01). CONCLUSION DASE allowed a higher first-session success rate and can be consider a valid alternative to endoscopic sphincterotomy not only for bigger CBD stones.

Extracting vanadium from stone-coal by oxygen pressure acid leaching and solvent extraction

Vanadium extraction from stone-coal was investigated by oxygen pressure acid leaching and solvent extraction.The mineralogy of the stone-coal from Tongren City of Guizhou Province,China,was investigated by various determination methods. The effects of leaching time,leaching temperature,leaching agent concentration,leaching L/S ratio,granularity of material,additive consumption were investigated based on the mineralogy.The results show that under the conditions of leaching time of 3-4 h, temperature of 150℃,sulfuric acid consumption of 25%?30%,ratio of liquid to solid of 1.2:1,the granularity less than 0.074 mm, additive consumption of 3%-5%,and oxygen pressure of 1.2 MPa,and the vanadium leaching rate can be more than 92%by the method of two-step pressurized acid leaching.The powdery V2O5 product with 99.52%in V2O5 content is obtained by the flowsheet of acid recovery,removing iron by reduction process,solvent extraction,precipitating vanadium with ammonium water,and pyrolysis from the stone-coal oxygen pressure acid-leaching solution.The total recovery efficiency of vanadium is above 85%,which is more than 20%higher than that obtained in the conventional process.Furthermore,the new process does not cause air pollution since no HCl or Cl2 is released by calcination of the raw material.

Enhanced properties of stone coal-based composite phase change materials for thermal energy storage

Phase change materials (PCMs) can be incorporated with low-cost minerals to synthesize composites for thermal energy storage in building applications.Stone coal (SC) after vanadium extraction treatment shows potential for secondary utilization in composite preparation.We prepared SC-based composite PCMs with SC as a matrix,stearic acid (SA) as a PCM,and expanded graphite (EG) as an additive.The combined roasting and acid leaching treatment of raw SC was conducted to understand the effect of vanadium extraction on promoting loading capacity.Results showed that the combined treatment of roasting at 900℃ and leaching increased the SC loading of the composite by 6.2%by improving the specific surface area.The loading capacity and thermal conductivity of the composite obviously increased by 127%and 48.19%,respectively,due to the contribution of 3wt% EG.These data were supported by the high load of 66.69%and thermal conductivity of 0.59 W·m^(-1)·K-1of the designed composite.The obtained composite exhibited a phase change temperature of 52.17℃,melting latent heat of 121.5 J·g^(-1),and good chemical compatibility.The SC-based composite has prospects in building applications exploiting the secondary utilization of minerals.

Dilation assisted stone extraction for complex biliary lithiasis:Technical aspects and practical principles

Common bile duct stones are frequently diagnosed worldwide and are one of the main indications for endoscopic retrograde cholangio-pancreatography.Endoscopic sphincterotomy(EST)has been used for the removal of bile duct stones for the past 40 years,providing a wide opening to allow extraction.Up to 15%of patients present with complicated choledocholithiasis.In this context,additional therapeutic approaches have been proposed such as endoscopic mechanical lithotripsy,intraductal or extracorporeal lithotripsy,or endoscopic papillary large balloon dilation(EPLBD).EPLBD combined with EST was introduced in 2003 to facilitate the passage of large or multiple bile duct stones using a balloon greater than 12 mm in diameter.EPLBD without EST was introduced as a simplified technique in 2009.Dilation-assisted stone extraction(DASE)is the combination of two techniques:EPLBD and sub-maximal EST.Several studies have reported this technique as safe and effective in patients with large bile duct stones,without any increased risk of adverse events such as pancreatitis,bleeding,or perforation.Nevertheless,it is difficult to analyze the outcomes of DASE because there are no standard techniques and definitions between studies.The purpose of this paper is to provide technical guidance and specific information about the main issues regarding DASE,based on current literature and daily clinical experience in biliary referral centers.

Effect of vanadium occurrence state on the choice of extracting vanadium technology from stone coal

The extraction technology of vanadium from stone coal by means of no-salt-roasting and dilute acid solution leaching treatment has the advantages of low pollution, low investment, as well as high vanadium leaching efficiency, which makes it the best technology for extending application. In the present study, the effects of vanadium occurrence state in stone coal, roasting temperature and additive agent on the leaching efficiency of vanadium were studied. The results indicate that the effect of vanadium occurrence state on the extracting vanadium technology is obvious. If the vanadium component in stone coal existed in amorphous phase form, this type of stone coal can be treated by no-slat-roasting and dilute acid solution leaching technology; while the vanadium-bearing crystalline phase existed in stone coal, the roasting additive must be added to destroy this crystalline form so as to acquire high vanadium leaching rate.

A new process of extracting vanadium from stone coal

A new process of extracting vanadium from the stone coal vanadium ore in Fangshankou, Dtmhuang area of Gansu Province, China was introduced. Various leaching experiments were carried out, and the results show that the vanadium ore in Fangshankou is difficult to process due to its high consumption of acid and the high leaching rate of impurities. However, the leaching rate can be up to 80% and the content of V2O5 in the residue can be between 0.22%-0.25% in the process of ore fme grinding→oxidation roasting→mixing and ripening→aqueous leaching→P2O4 solvent extraction→sulfuric acid stripping→oxidation and precipitation→decomposition by heat. Also, the quality of flaky V205 produced by this process can meet the requirements of GB3283--87. The total leaching rate of vanadium is 70%. Also, three types of wastes are easy to treat. The vanadium extraction process is better in relation to the aspect of environmental protection than the sodium method.

Antilithic Effects of Extracts from Urtica dentata Hand on Calcium Oxalate Urinary Stones in Rats

This study examined the potential antilithic effects of a traditional Chinese medicine Urtica dentata Hand （UDH） in experimental rats and screened the optimal extract of UDH as a possible therapeutic agent for kidney stones. The rat model of urinary calcium oxalate stones was induced by intragastric （i.g.） administration of 2 mL of 1.25% ethylene glycol （EG） and 1% ammonium chloride （AC） for 28 days and was confirmed by Color Doppler ultrasound imaging. The rats in different experimental groups were then intragastrically given petroleum ether extract （PEE）, N-butanol extract （NBE）, aqueous extract （AqE） of UDH, Jieshitong （positive control drug）, and saline, respectively. Treatment with NBE significantly reduced the elevated levels of urinary calcium, uric acid, phosphate, as well as increased urinary output. Accordingly, the increased calcium, oxalate levels and the number of calcium oxalate crystals deposits were remarkably reverted in the renal tissue of NBE-treated rats. In addition, NBE also prevented the impairment of renal function to decrease the contents of blood urea nitrogen （BUN） and creatinine. Taken together, these data suggest that NBE of UDH has a beneficial effect on calcium oxalate urinary stones in rats by flushing the stones out and protecting renal function.

无线便携式腔镜在胆总管切开取石术中的应用

目的探究无线便携式腔镜在胆总管切开取石术中的应用效果。方法对2023年6月至11月期间78例在武警安徽总队医院普外科接受胆总管切开取石术的胆石症患者进行回顾性分析,根据术中所采用设备的差异,分为无线腔镜组和传统有线腔镜组,各39例。比较两组的围手术期指标、扶镜者疲劳度评分、血清肿瘤坏死因子(TNF-α)、白介素1β(IL-1β)和C反应蛋白(CRP)等。结果所有手术均成功完成,观察组和对照组在手术时间、失血量、手术难度评分、术后引流管留置时间、住院时间、术后并发症和患者疼痛视觉模拟量评分等均无显著差异(P>0.05),两组间术前准备时间和扶镜者疲劳度评分差异具有统计学意义(P<0.01)。两组治疗后血清TNF-α和IL-1β的水平无显著差异(P>0.05),但两组治疗后血清CRP的水平差异具有统计学意义(P<0.01)。结论无线腔镜较有线腹腔镜在手术效果等方面没有差异,但能缩短术前准备时间、减轻扶镜者疲劳度、减少线缆对术者的羁、提高手术操作便携性。其优化了手术效率,更有利于未来在野外环境进行手术救治。

汉画像石中虎造型在文创产品设计中的应用研究

基于汉画像石虎造型的文创产品的设计研究。通过阅读相关文献,对汉画像石中虎造型形态特征、线条特征以及文化内涵进行归纳梳理,综合运用元素提取法、风格沿用法、元素转译等设计方法。设计出了《瑞兽福虎》系列纹样及文创产品。在设计案例中验证了研究思路的可行性,实现了汉画像石虎造型与现代设计的融合。提出设计者在进行文创产品的设计时,不仅要了解产品的功能,同时也要兼顾产品与文化内涵间桥梁的架构。

N235从高碳石煤脱碳渣酸浸液中萃取钒的工艺研究

以某地高碳石煤脱碳渣经空白焙烧-酸浸后的浸出液为原料,采用萃取剂N235和反萃剂Na_(2)CO_(3)对钒萃取工艺和反萃取工艺进行了研究。结果表明,最佳萃取工艺参数为:萃原液pH值2.3、有机相组成为15%N235+5%仲辛醇+80%磺化煤油、相比(O/A)1∶4、萃取时间4 min、氧化剂氯酸钠用量为萃原液V_(2)O_(5)质量的0.05倍、萃取级数五级,钒萃取率达99%;最佳反萃工艺参数为:反萃剂Na_(2)CO_(3)溶液浓度8%、反萃相比(O/A)4∶1、反萃时间10 min、反萃级数三级,钒反萃取率可达99.50%。在最佳萃取和反萃取工艺条件下,钒浓度由4.25 g/L富集到68.50 g/L,且pH值为8.5,无需中和处理。对富钒液进一步沉钒、煅烧得到的最终产品V_(2)O_(5)品位为98.95%,且杂质含量低,满足行业标准YB/T 5304—2017中98级V_(2)O_(5)的要求。

A review on vanadium extraction techniques from major vanadium-containing resources

The critical role of vanadium in metallurgy and the increasing commercialization of vanadium redox flow batteries have contributed to a rise in market demand for vanadium,emphasizing the need to ensure the sustainability of vanadium production.Converter vanadium slag and stone coal,generated during the smelting process of vanadium–titanium magnetite,serve as primary raw materials for vanadium extraction.This paper reviews the process mineralogy of converter vanadium slag and stone coal,encompassing the chemical and physical phase compositions of the raw materials and the state of vanadium occurrence.The aim is to establish a theoretical foundation for the mechanistic study of the vanadium extraction techniques and to provide a reference for the optimization of the process afterward.This paper systematically summarizes the current vanadium extraction technology from converter vanadium slag,covering roasting,direct leaching,sub-molten salt method,and the technology and research status of vanadium extraction from stone coal.Most importantly,it identifies key issues in the current vanadium extraction techniques and challenges faced in actual production,based on the analysis of the current vanadium extraction process and mechanism research.The forward feasibility and prospects for the development of vanadium extraction technology are outlined.

稀土元素铈的提取工艺研究进展

铈(Ce)是稀土元素系列之一,随着高科技的发展,铈元素在环境保护、工业生产、光学和材料领域的应用需求越来越多。目前已实现商业规模开采的含铈矿物有氟碳铈矿和独居石。本文主要综述了采用重选、磁选、静电分选、浮选等方法对含铈矿石进行精选,继而采用吸附法、化学沉淀法和溶剂萃取法等从含铈精矿提取铈元素的冶金工艺研究进展,为下一步发展高效、环保的提取技术,制备高质量铈元素产品满足市场需求,提供研究思路。

石煤钒矿低温硫酸熟化-水浸提钒工艺

这是一篇冶金工程领域的论文。以陕西某地含钒矿物为绢云母、伊利石的石煤钒矿为研究对象,采用低温硫酸熟化-水浸工艺提钒,考查了熟化温度、熟化时间、硫酸用量、氯化钠用量,浸出温度、浸出时间及浸出液固比对钒浸出率的影响。结果表明:向石煤钒矿中加入25%的硫酸、0.8%的氯化钠,在130℃下熟化8 h,熟化样品在浸出温度55℃、液固比1.5∶1的条件下浸出时间2 h,钒浸出率可达89%。这说明采用低温(130℃)硫酸熟化-水浸工艺提取石煤型钒矿是可行的。

肝胆管结石病微创治疗的研究现状

肝胆管结石病是一种常见的良性临床疾病,但肝胆管结石病经常伴随着反复的胆管炎发作,可导致肝脓肿、肝萎缩和肝纤维化。肝胆管结石病处理方法越来越多样,但治疗原则依然遵循“去除病灶、取尽结石、矫正狭窄、通畅引流、防治复发”的20字方针。手术微创化是当前外科学发展的一大趋势,尤其是在肝胆管结石病的治疗方面也有显著的进展。微创治疗不仅减少传统开放手术对身体的创伤,给患者提供更优质的治疗,还可降低患者的住院时间和费用。在已有文献的基础上,从介入治疗、腹腔镜手术治疗、内镜治疗3个方面,综述了近年来肝胆管结石病微创手术治疗的现状,旨在寻找最优方案,为患者提供更优质的治疗服务。

陕西某地石煤钒矿制备五氧化二钒产品工艺研究

采用硫酸熟化-水浸工艺从石煤钒矿中提钒,考察了熟化条件及浸出条件对钒浸出率的影响。结果表明,适宜的熟化工艺条件为:熟化温度130℃、熟化时间8 h、H_(2)SO_(4)用量25%。对熟化料进行水浸,在浸出温度90℃、浸出时间120 min、液固比2∶1条件下,钒浸出率为90.79%。对含钒浸出液用NaClO_(3)进行氧化,采用D202吸附氧化后液中的钒,再对树脂中钒进行解吸,解吸液经沉钒煅烧后五氧化二钒产品纯度达99.21%,钒总回收率为85.99%。

Mechanical lithotripsy and/or stenting in management of difficult common bile duct stones

BACKGROUND:Mechanical lithotripsy and/or stent insertion is the alternative therapeutic approach in difficult endoscopic retrograde cholangiopancreatography (ERCP)case.This study was designed to investigate the appropriate treatment for extraction of bile duct stones in difficult cases of ERCP. METHODS:Between 2000 and 2008,744 ERCP procedures were performed in 592 patients with choledocholithiasis in our endoscopy unit.The demographic features,and clinical and laboratory findings were collected from a prospectively held database.Bile duct calculi were extracted by basket and/or balloon catheter following ERCP and sphincterotomy.Patients with retained stones were regarded as difficult cases.These patients were treated with mechanical lithotripsy and those with incomplete clearance of stones underwent stent placement. RESULTS:Two hundred and forty-five patients(41%) were male and 347(59%)were female with a mean age of 58 years(range 19-95 years).Stones were impacted in 27 patients(5%).Stone extraction was performed by basket and/or balloon catheter in 610 ERCP procedures,and lithotripsy was performed in 70 ERCP procedures.Forty- four patients underwent stent insertion,and 20 underwent stent replacement.Morbidity occurred in 39 patients (5%),with no mortality associated with the procedure.Hemorrhage occurred in 9 patients and basket impaction in 4.Mild pancreatitis and cholangitis developed in 12 and 11 patients,respectively. CONCLUSION:Difficult cases of bile duct stones can be treated successfully with lithotripsy,and a stent should be applied when the common bile duct cannot be cleared completely.

Bioleaching of vanadium from barren stone coal and its effect on the transition of vanadium speciation and mineral phase

This study determined the optimal conditions required to obtain maximum vanadium extraction and examined the transition of mineral phases and vanadium speciation during the bioleaching process. Parameters including the initial p H value, initial Fe^(2+) concentration, solid load, and inoculum quantity were examined. The results revealed that 48.92 wt% of the vanadium was extracted through bioleaching under optimal conditions. Comparatively, the chemical leaching yield(H_2SO_4, pH 2.0) showed a slower and milder increase in vanadium yield. The vanadium bioleaching yield was 35.11 wt% greater than the chemical leaching yield. The Community Bureau of Reference(BCR) sequential extraction results revealed that 88.62 wt% of vanadium existed in the residual fraction. The bacteria substantially changed the distribution of the vanadium speciation during the leaching process, and the residual fraction decreased to 48.44 wt%. The X-ray diffraction(XRD) and Fourier transform infrared(FTIR) results provided evidence that the crystal lattice structure of muscovite was destroyed by the bacteria.

Calcified roasting-acid leaching process of vanadium from low-grade vanadium-containing stone coal

The low-grade vanadium-containing stone coal used in this experiment was collected from Wuxi Country, Chongqing City, China. The experiment focused on the vanadium recovery from roasted residue through optimizing the process conditions of an effective and environmentally-friendly technology, named calcified roasting-sulfuric acid leaching technology. By single-factor experiments and orthogonal experiments, the effects of roasting temperature, roasting time, sulfuric acid concentration and leaching time on the leaching ratio of vanadium were analyzed. The results showed that the leaching ratio of vanadium reached 85.5% under the proper technological conditions of roasting temperature=950℃, roasting time=4 h, 40% concentration of sulfuric acid and leaching time=6 h.