STORAGE OF PITCHING YEAST FOR PRODUCTION OF WHISKY

The viability of pitching yeast stored at 5°C and at 20°C was compared. The viability of the yeast stored at 5°C was about 80% after 54 d storage and its CO₂ producing activity also remained high. The ethanol production rate of yeast stored for a long period at 5°C was unaffected in a subsequent fermentation test, even though the viability was only about 50%. The ethanol production rate of yeast stored at 20°C decreased in proportion to a rapid decrease in viability during storage. The concentration of intracellular sulphur compounds, important for the production of aromatic components of whisky, of yeast stored at 5°C was higher than that of yeast stored at 20°C. Therefore, the storage of yeast at 5°C seems appropriate for production both of ethanol and aroma.     

Effects of applying sodium and sulphur fertilisers on the concentrations of elements in water leached from permanent pasture

The element composition of water leached from a perennial ryegrass pasture to which isonitrogenous quantities of sodium nitrate, ammonium nitrate or ammonium sulphate fertilisers had been applied in an experiment lasting 2 years is described. The experimental design also allowed a comparison of the immediate effects of sodium nitrate in the grazing season in which the fertiliser was applied with the residual effects of applying it in the previous year. Applying sodium fertiliser in either 1992 or 1993, but not both years, increased the concentrations of sodium, potassium, magnesium, calcium and cobalt and reduced those of phosphorus and molybdenum in leachate. The application of sulphur fertiliser reduced the concentrations of zinc, copper, iron and molybdenum in leachate. It also reduced the concentrations of sodium, potassium and magnesium, but only when sodium fertiliser was applied in 1992, and not when it was applied in 1993. It is concluded that sulphur fertiliser reduces the leaching of trace elements from the soil and that, in the long term, sodium fertiliser can amplify the effect of applying sulphur fertiliser. Sodium fertiliser in moderate quantities increased the leaching of the major divalent cations but reduced the phosphorus and molybdenum concentrations in leachate. © 2002 Society of Chemical Industry     

Growth and development ofThiobacillus ferrooxidans for engineering applications

A bioprocessing approach for the extraction of base, nuclear and precious metals from refractory and lean grade ores has been reviewed in this paper. Characteristic morphological features ofThiobacillus ferrooxidans, the organism which has been extensively used for biooxidation of sulphide ores have been discussed. Mechanisms of chemoautotrophy and mineral oxidation have been illustrated. The current engineering applications of this microorganism have also been brought out. Various methods for accelerating the growth ofThiobacillus ferrooxidans for faster biooxidation and genetic manipulation for development of desired strains have been outlined.     

硫磺市场供需平衡展望

自1992年以来，国际硫磺市场一直呈现表观上的供大于求。2002年硫磺产量超过消耗量将近1．9Mt，但硫磺的供应却日趋紧张，温哥华的硫磺出口价格达到自20世纪90年代初期以来的最高水平。这种表观上的矛盾——价格上扬伴随着硫磺生产过剩，是由于产品在投放市场时遭遇到资金和物流方面的重重困难，库存量增大。预测硫磺市场将在2008年趋于平衡，到2009年可能重新转向供应短缺。这种观点所依据的主要假设为：在供应方面，酸性气体回注技术将会减缓回收硫磺数量的增长速度；在需求方面，中国对全形态硫的需求以及钴酸浸操作对硫磺的需求会大幅增长。     

40 kt/a硫酸系统的挖潜改造

介绍40kt/a硫铁矿制酸装置的挖潜改造。装置原采用文-泡-电水洗净化、一转一吸工艺，技术经济指标差，环境污染严重。通过将工艺原料改为固体颗粒硫磺及更新设备，装置生产能力达60kt/a以上，改进了技术经济指标，减轻了环境污染。     

锅炉麻石水膜除尘器的脱硫改造工艺

对20t蒸汽锅炉麻石水膜除尘器脱硫改造的工艺进行了介绍。     

灯芯绒霜花工艺

介绍了几种常用的灯芯绒霜花工艺,重点推荐了连续式花筒霜化工艺;给出了前处理、染色、氧化的工艺处方,以及各道工序的注意事项;探讨了割绒工艺中漏割、粗细条等疵病产生的原因,包括染料、氧化剂的选择等;简述了最新的服装霜花工艺.     

水煤浆燃中固硫技术研究

对水煤浆燃烧固硫问题进行了初步探讨 ,指出水煤浆燃烧过程中结渣主要是常用的水煤浆添加剂会导致水煤浆的灰熔点下降所致 ;如果直接以钙系化合物作为水煤浆固硫剂 ,将导致水煤浆的灰熔点进一步下降 ,有时还会大大增加水煤浆的粘度 ,降低水煤浆的稳定性。因此 ,为了使水煤浆具有合适的粘度、稳定性 ,保持较高的灰熔点 ,同时实现水煤浆燃中固硫之目的 ,必须综合考虑添加剂和固硫剂的成分和用量。     

流化床石灰石脱硫应用技术分析

分析石灰石固硫特性，介绍利用石灰石脱硫技术的新发展，探讨石灰石在循环流化床脱硫过程中不同应用方法。     

考虑井筒硫析出的高含硫气井井筒温度、压力场计算新模型

在高含硫气井的日常管理及气井设计、动态分析中,井筒压力、温度分布是两个重要的参数,而气体中富含H₂S和CO₂以及流动过程中硫颗粒的析出是导致高含硫气井井筒温度、压力分布计算偏差的两个关键因素。为此,以实验数据为基础,对物性参数计算方法进行优选,提出了采用DPR模型结合WA校正法和Dempsey模型结合Standing校正法作为计算高含硫天然气压缩因子和黏度的模型,根据传热学和气-固两相流动理论,建立了考虑井筒硫颗粒析出的井筒温度、压力分布计算新模型。运用该模型对某高含硫气井井筒温度、压力、井筒析出硫颗粒体积进行了计算,温度、压力的计算值与实测值最大误差分别为2.67%和2.32%,表明新模型计算精度较高,适用于高含硫气井井筒温度、压力分布和析出硫颗粒体积的计算与分析。