Portland filter

The Portland filter is built in drum sizes of 6, 8, 12 and 14 ft. diameter and with various width of face up to 16 ft. The Oliver filter is built in the following sizes of filter drum ... 

Chrysotile is a noncombustible fibrous solid that has been widely used as a fireproof thermal insulator, for brake linings, in construction materials, and for filters under the name of asbestos. It decomposes with loss of water at 600-800 °C, eventually forming forsterite and silica at 810-820 °C. Because it is more resistant to attack by alkalis than are the amphibole asbestoses, chrysotile has been used in chloralkali cell membranes and in admixture with Portland cement for making sewer pipes (Chapter 11). 

A portland cement plant ball mill emits particulate matter (PM) emissions that must be controlled to meet state air pollution regulations. Three PM control devices, each of which can control these emissions to the same level, are being evaluated (1) a high-energy wet scrubber (scrubber), (2) an electrostatic precipitator (ESP), and (3) a fabric filter (baghouse). Unlike the wet scrubber, the ESP and the baghouse each recover salable cement dust, and, accordingly, revenue can be attributed to those two options. Two scenarios are visualized, with after-tax hurdle rates of 6% and 18%, respectively. The economic specifications for the three devices are as follows ... 

D. S. Ensor, R. G. Hooper, R. C. Carr, and R. W. Sclieck, "Evaluation of a Fabric Filter on a Spreader Stoker Utility Boiler," Preprint 76-27.6, 69th APCA Annua/ Meeting, Portland, Oregon, June 27-July 1, 1976. 

FIGURE 11.7 Ordered arrays formed from filtered latex suspensions (Photo from Interfacial Dynamics Corporation, Portland, Oregon. Reprinted with permission.)... 

Fig. 5. Results from the covert action laser illuminator (CALI) inside a FLIR turret in combination with a NIR-sensitive CCD camera. Left Approaching the vessel using the thermal camera (mid-IR) and the autotracker. Right Laser-illuminated stem of the ship, supplied by the CCD camera with disabled NIR-cut filter. The images were taken during an exercise in Portland, Oregon with ships abiding by the regulations...

LC Analyses, LC analyses were performed by using a Waters 600 pump equipped with a Rheodyne Model 7725i manual injector (50 pL loop) and a Waters Model 991 photodiode array detection system. Chromatographic separation was achieved on a YMC Pack PolymerCtS (YMC Inc. Wilmington, NC) column with a OPTI-SOLV mini filter (Optimise Technologies Inc., Portland, OR). The linear gradient was 60% H2O (solvent A)/40% acetonitrile (solvent B) which was held for 10 min, then increased by 8% acetonitrile/min to 20% H2O/80% acetonitrile, and held for 15 min. The flow rate was 0.8 mL/min. 

Generally, concrete used for water treatment plant pipes, water tanks, and filters is made using (ordinary) Portland cement, whereas cement-mortar linings can be made of diflerent types of cements, such as Portland cements, blast furnace cement or the non-Portland calcium aluminate cement. Each type of cement has a typical composition. Table 4.14 gives the typical composition of the primary cements used for manufacturing pipe. 

Jarofix products, which were prepared in the laboratory by Noranda Inc., CEZinc and the Noranda Technology Centre and stored in plastic containers for more than 6 years, were also studied. The jarofix products were prepared from mixtures of Na-jarosite residue, Portland cement and a proper amount of water to give an acceptable workability. The mixtures were thoroughly blended, cast into cylindrical molds, cured, and stored in the laboratory for more than 6 years. Gypsum filter cake and lime were not part of the mixtures. The samples were analyzed after 3 months, after >4 years and after >6 years of storage. 

Work at Courtaulds [22,23] in the early 1970s attempted to incorporate carbon fiber in a cement slurry, which was difficult due to the size of the cement particles. They tended to be filtered out by the fiber reinforcement, so a cement with a fine particle size (Swiftcrete, an ultra rapid hardening Portland cement with a maximum diameter of about 45 pm) was used and the fiber spread as thinly as possible, using either an air knife, or a water flume and then held in the spread position by sizing with a water based compatible size such as sodium carboxymethylcellulose [22,23]. These larger particles limit the carbon fiber content to about 5% v/v, but in practice, due to a non-uniform distribution, a value of some 12% v/v was attainable. 

Sedra, A.C. and Brackett, P.0.1978. Filter Theory and Design Active and Passive. Matrix, Portland, OR. Seidman, A. 1983. Integrated Circuits Applications Handbook. Wiley, New Yorlc. 

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