Dorr-Oliver

Three-phase fluidized bed reactors are used for the treatment of heavy petroleum fractions at 350 to 600°C (662 to 1,112°F) and 200 atm (2,940 psi). A biological treatment process (Dorr-Oliver Hy-Flo) employs a vertical column filled with sand on which bacderial growth takes place while waste liquid and air are charged. A large interfacial area for reaction is provided, about 33 cmVcm (84 inVirr), so that an 85 to 90 percent BOD removal in 15 min is claimed compared with 6 to 8 h in conventional units. 

Figure 3-16. Stuffing box details lined pump with porcelain or teflon shaft sleeve. (Courtesy Dorr-Oliver, Inc.)...

There are several variants of the Dorr process which differ according to the treatment of the calcium sulfate. Some variants produce the dihydrate, gypsum, others produce the hemi-hydrate. The variants also differ in the concentration of the phosphoric acid produced, but it is never more than 43 percent. The basic process was patented by Lawes in England in 1842 but the presently used variant was developed by the Dorr-Oliver company in the 1930s. Stevens, H. M., Phosphorus and Its Compounds, Interscience, New York, 1961. 

Dorr-Oliver One of the wet processes for making phosphoric acid. See Dorr, Jacobs-Dorr. 

OXITRON A municipal sewage treatment process designed by Dorr Oliver. Starfish Industries, UK, has adapted it for coastal towns. The reactor is a biological fluidized bed installed on the seabed. 

Dorr-Oliver, 1990. DSM Screens for the Food Industry. Bulletin DSM 5. 

Dorr-Oliver slurry-fed roaster, 26 563 Dortmund-Hoerder (DH) process,... 

The labor intensive replacement of membranes in plate and frame systems has been facilitated in the "leaf-module" design of Dorr Oliver (Figure 16). Here a number of plates are assembled in a disposable cartridge where the process stream flows over the plates and the permeate is ducted to a common header. 

Figure 16. Dorr Oliver leaf-module design (6)...

Air stripping of pharmaceutical wastewater is a partial treatment used in particular for the removal of volatile organics from wastewater. M/S Hindustan Dorr Oliver, Bombay, in 1977 studied the effect of air stripping on the treatment of pharmaceutical wastewater and reported that a COD removal efficiency up to 30-45% can be achieved by air stripping. It was found that adding caustic soda did not appreciably increase the air stripping efficiency. 

Hindustan D.O. Studies on Pharmaceutical Wastewater Park-Davies, Hindustan Dorr Oliver Bombay, India. 

Fig. 3. Separation efficiency of HeLa cells when using a 10 mm Mozley hydrocyclone, a 10 mm Dorr-Oliver hydrocyclone and a 7 mm Bradley hydrocyclone [65]...

Liibberstedt [64] tested three different hydrocyclones for HeLa cell separation a 7 mm Bradley [67], a 10 mm Mozley (Richard Mozley Ltd., Redruth, UK), and a 10 mm Dorr-Oliver (Dorr-Oliver GmbH, Wiesbaden, Germany) (the dimension quoted here is the diameter of the cylindrical part of each hydrocyclone). The best results were obtained with the Dorr-Oliver hydrocyclone (Fig. 3), which produced a cell separation efficiency of 81 % when working at a pressure drop of 300 kPa and a flow rate of 2.8 L min When operating with two 10 mm Dorr-Oliver connected in series (the overflow of the first as feed for the second) at 200 kPa, the global efficiency of the arrangement was 94% [65]. These experimental values confirm the computational fluid dynamics (CFD) predictions that high levels of efficiencies for mammalian cells could be achieved with small diameter hydrocyclones [46]. 

Fig. 4. Influence of pressure drop on ceU viability in the underflow and overflow of the following hydrocyclones Dorr-Oliver (a),Mozley (b) and Bradley (c) with diameters of 10 mm, 10 mm and 7 mm, respectively [66]...

Feed Launders for M/s. Hindustan Dorr-Oliver Ltd, India... 

Figure 11.11. Continuous horizontal vacuum filters especially suited to free settling and draining solids, (a) Principle of the conveyor belt filter units may operate up to 0.S m/sec with a cycle time up to 10 min and produce cake thicknesses up to 15 cm. (b) Showing the construction of a grooved rubber belt support for the filter cloth of the belt filter (Purchas, 1981). (c) Rotating horizontal vacuum filter the unit has readily accessible piping and is amenable to thorough washing of free draining solids (Dorr-Oliver Inc.).

Dorr-Oliver Inc., Filtration Leaf Test Procedures. Stamford, CT Dorr-Oliver Inc., 1972. 

Figure 9.6 Detail of equipment arrangement and water and process stream flow employing the high-density, four-stage separation centrifugation system. (Courtesy of Dorr-Oliver, Inc., Stamford, Connecticut)...

Chiang WC, Lee A New Developments for Improving Starch-Gluten Separation. Milford, CT Dorr-Oliver 1995. 

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