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A new technique for simultaneous grinding and hydrating of fluidized bed combustion (FBC) bottom ash has been developed. This method has been shown to be effective in hydrating the CaO component of the ash, so that the sorbent is reactivated. Careful control of water levels is required to prevent energy demand increases for grinding. No problems associated with the potentially exothermic reaction of water with FBC bottom ash have been observed during grinding. When excess water (over that required by hydration) is used, the resulting material is a slurry and, while quantitative conversion of CaO in the solids is achieved, using the slurry for the sorbent would require a redesign of the limestone feed system. Therefore, coal or unreacted ash is added to the mixture after grinding. The resulting dry product contains the spent bed material in a completely hydrated form. The reactivated ash produced has been evaluated for sulfur capture using thermogravimetric analysis and a CFBC pilot plant. Conversion rates of almost 100% are achieved for ash after grinding hydration. An industrial demonstration of the technology has supported its viability with no decrease in sulfur capture, while limestone requirements decreased by 18%. The economic implications of the industrial applicability of the technology are outlined in a case study using the Point Aconi CFBC unit. Decreased limestone usage is calculated to net savings in the order of $500000/year. The project is calculated to have an equity payback of less than 1 year.

Barley, after steeping in water, was ground with ease and efficiency in the Szegomill, and its starch was liquefied, saccharified and fermented to very high yields of ethanol. The Szegomill consists of vertical rollers with helical grooves which rotate within a fixed cylinder, resulting in very fine grinding and a somewhat flaky product. The steeped barley was ground to a fine paste. This was readily liquefied and saccharified by amylolytic enzymes (dual enzyme process), and the resulting sugars were fermented in 24 h by ordinary bakers' yeast Saccharomyces cerevisiae, resulting in over 450 1 ethanol/t of barley. Still shorter time, 12 h, and the same high yield were achieved when liquefied barley starch was simultaneously saccharified by glucoamylase and fermented. Fermentation to ethanol by a glucoamylase‐producing yeast S. diastaticusstrain 164 A (from Labatt Brewing Company) enabled the amount of this enzyme required for saccharification to be reduced to about one‐half the normal quantity, but at some cost in slower fermentation and slightly lower ethanol yield. Verzuckerung und Vergärung von mittels der Szego‐Mühle vermahlener Ganz‐Gerste. Nach Quellung in Wasser wurde Gerste problemlos und wirkungsvoll in einer Szego‐Mühle vermahlen. Die Stärke wurde dann verflüssigt, verzuckert und mit hohen Ausbeuten an Ethanol vergoren. Die Szego‐Mühle besteht aus vertikalen Walzen mit schraubenförmigen Rinnen, die in einem feststehenden Zylinder rotieren, wodurch eine feine Vermahlung stattfindet und ein flockiges Produkt entsteht. Die gequollene Gerste wurde zu einer feinen Paste vermahlen. Diese ließ sich durch amylolytische Enzyme leicht verflüssigen und verzuckern (Enzym‐Enzym‐Verfahrea), und die entstandenen Zucker wurden 12 h durch gewöhnliche Bäckerhefe (Saccharomyces cerevisiae) vergoren mit einer Ausbeute von mehr als 450 I Ethanol/t Gerste. Eine noch kürzere Zeit, 12 h, und eine gleichgroße Ausbeute wurden erreicht, wenn die verflüssigte Gerstenstärke durch Glucoamylase verzuckert und gleichzeitig vergoren wurde. Die Vergärung zu Ethanol durch eine Glucoamylase bildende Hefe S. diastaticusdes Stammes 164A (von der Labatt Brewing Company) machte cs möglich, die Menge dieses für die Verzuckerung erforderlichen Enzyms auf etwa die Hälfte der normalen Menge zu verringern, allerdings auf Kosten einer langsameren Gärung und geringfügig niedrigerer Ethanolausbeute.

Results from a systematic grinding study with the SM-320 Szego Mill are reported. A wide range of flow rates, from 750 to 5300 kg/h of coal, at 60-65% solids concentration has been covered, with both single and multiple passes through the mill. Particle size distributions and power consumption have been measured. Data, including those for energy consumption, have been correlated in terms of the mass fraction of particles passing various mesh sizes 45 μm and up.A dynamic wet-grinding model recently developed for the Szego Mill is reviewed. Use of this model allows a priori predictions of limiting performance for all design and operating variables in the "paste grinding" regime, i.e., at relatively high solids concentrations which are optimal for wet grinding in the Szego Mill. Limiting size predictions for the SM-320 mill and the conditions used are presented along with an initial attempt to incorporate the breakage function in the model. Predictions confirm the observed effects of feed rate and number of passes of material through the mill

To evaluate the magnitude and duration of the antihypertensive effect of sustained release (SRO) isradipine, 37 uncomplicated essential hypertensive patients (diastolic blood pressure 100–115 mm Hg after a one month run-in on placebo) were randomised to receive, according to a double-blind cross-over design, isradipine SRO 5 mg once daily and the corresponding placebo for 1 month. At the end of each treatment period, sitting blood pressure and heart rate were measured immediately before and every hour for 6 h after the last dose. Thirty-four patients [16 m, age 54 (7) y] completed the study.