铝土矿浮选尾矿制备聚合硫酸铝铁的研究

某铝土矿浮选尾矿在600 ℃下焙烧3 h后,按照硫酸溶液（浓度45%）与焙砂5∶1的液固比,在100 ℃下浸取3 h,铝、铁的浸出率分别达到61.65%和94.10%。浸出液中通过适量添加硫酸亚铁和双氧水,制备的聚合硫酸铝铁液态产品符合国家标准。不同水样的混凝试验结果表明,该产品对于浊度的降低和固体悬浮物的去除具有较好效果。     

含钒石墨尾矿提钒技术研究

金溪石墨矿矿石中钒含量较高,研究表明矿石经石墨浮选后钒绝大部分都进入尾矿中,因此从尾矿中回收钒成为开发金溪石墨矿必须解决的问题。为此,根据矿石中钒的特点,在借鉴石煤提钒技术的基础上,对浮选试验获得的金溪石墨尾矿进行了提钒试验。试验结果表明：采用加酸焙烧-水浸-除钾铝-萃取-反萃取-氧化沉钒工艺,可使金溪石墨矿浮选尾矿中钒的浸出率、萃取率、反萃取率和沉淀率分别达到95.5%、87.6%、99.9%和99.0%,同时可获得对浮选尾矿产率分别为9.2%和23.2%的钾明矾和铵明矾;此外,浸出渣主要由硅酸盐组成,并具有较高的活性,可以作为水泥掺合料和生产建筑材料的原料。     

高砷高硫金精矿提金工艺研究

介绍了某金矿氰化尾矿的摇床重选精矿的物质组成研究和多种提金工艺研究。研究结果表明，不利于金的直接氰化浸出的原因是硫化物包裹金占有率高，浸出的有害杂质As、Cu、Bi、Sb含量较高，与Au关系密切，相互胶结和共生，沸腾炉焙烧后，焙砂As、Se脱除率高，金属硫化物基本上完全转化为疏松多孔状的铁氧化物，提高了金的浸出率，金的浸出率达96.95%，认为是适合于处理某金矿氰化尾矿的摇床重选精矿的提金工艺。     

含锑金矿回收方法研究现状

本文简要介绍了我国含锑金矿分布与资源特点,针对其回收存在难点与问题,评述了我国含锑金矿几种主要回收方法,包括浮选法、焙烧法、生物法、化学碱浸法、强化浸出法等,指出了各回收方法优缺点及适用范围,并提出了今后研究重点在于强化浸出及联合应用方面。     

微波加热预处理一水硬铝石矿的工艺研究

利用微波加热对我国一水硬铝石矿进行了活化焙烧的实验研究,以降低拜耳法溶出的温度。从微波添加剂、微波加热功率和微波加热时间对铝土矿的溶出性能的影响等方面进行了研究。并利用SEM技术对活化焙烧矿的微观形貌进行了分析。实验结果表明,微波加热焙烧的最佳工艺条件为:NaOH添加量100 kg/t,微波加热温度535℃,加热时间5 min。短时间的微波辐射就能使矿石的微观形貌发生显著变化。     

高铜金精矿提取金铜工艺研究

采用硫酸化焙烧——二段酸浸——氰化工艺处理高铜金精矿。结果表明,在600℃硫酸化焙烧,焙砂在一段弱酸、二段强酸,温度80℃,浸出90 min的条件下,铜浸出率为98.22%;再对酸浸渣进行氰化浸出,金浸出率高达99.14%。     

碱法从石煤中浸出钒试验研究

采用造球—氧化焙烧—碱浸的方法从石煤中浸出钒,考察了焙烧温度、焙烧时间、浸出温度、浸出剂浓度、浸出时间、浸出液固比对浸出率的影响,获得了88.38%的高浸出率。研究表明,焙烧温度、浸出温度、浸出剂浓度、浸出时间是浸出率的重要影响因素。适宜的工艺条件是:焙烧温度850℃、焙烧时间3 h、浸出温度90℃、浸出剂浓度2 mol/L、浸出时间2 h、浸出液固比3。     

Shelf-life of infrared dry-roasted almonds

Infrared heating was recently used to develop a more efficient roasting technology than traditional hot air roasting. Therefore, in this study, we evaluated the shelf-life of almonds roasted with three different approaches, namely infrared (IR), sequential infrared and hot air (SIRHA) and regular hot air (HA). Nine medium roasted almond samples produced by the aforementioned heating methods were processed at three different temperatures (130, 140 and 150 °C), packed in paper bags and then stored at 37 °C for three, six or eight months. Shelf-life of the roasted almonds was determined by measuring the changes in colour, peroxide value, moisture content, water activity, volatile components and sensory quality. No significant difference was observed in moisture content and water activity among the almond samples processed with different roasting methods and stored under the same conditions. GC/MS analysis showed that aldehydes, alcohols, and pyrazines were the main volatile components of almonds. Aliphatic aldehydes such as hexanal, (E)-2-octenal, and nonanal were produced as off-odours during storage. Although the overall quality of roasted almonds produced with SIRHA and HA heating was similar during the first three months of storage, their peroxide value and concentration of aliphatic aldehydes differed significantly for different roasting methods and increased significantly in all roasted samples during storage. We postulate that hexanal and nonanal might be better indicators of the shelf life of roasted almonds than the current standard, peroxide value.     

φ7580mm花板拼焊质量的保证

介绍了年产２０００００ｔ硫酸工程的沸腾焙烧炉７５８０ｍｍ花板制作、安装过程和拼焊质量的保证。     

The effect of post-mortem ageing and heating on water retention in bovine muscles

The muscles semitendinosus (ST) and psoas major (PM) were removed from chilled young bull carcasses 24 h after slaughter and stored at 4 °C. At the 1st, 6th and 12th day of post-mortem ageing the chemical composition (moisture, fat, protein, collagen) and contents of free, immobilized and unfreezable water in the muscles were estimated. The muscle steaks were boiled at 100 °C, roasted at 170 °C or fried at 160 °C to an internal temperature of 75 °C, and the amounts of total, free, immobilized, and unfreezable water in heated muscles were evaluated. The unfreezable water was estimated by DSC. In the raw muscles immobilized water constituted 74–75%, free water 16.6–17.6% and unfreezable water 7–8% of the total water. Independent of time of ageing, PM muscle contained significantly more free water than ST muscle. During post-mortem ageing, changes in free, immobilized and unfreezable water in muscles were not significant. The level of free water was highest in boiled and least in fried meat, however the amount of immobilized water was highest in fried and lowest in boiled meat. The amount of unfreezable water in muscles heated after 12 days of post-mortem ageing decreased.