Agitators propeller-type

Ag-309 to Ag-312 4 Agitators for hold tank, propeller type, 50 hp. Stainless steel. 

One way to estimate prices of items when they cannot be found is to compare them with other items that might be similar or to items that might be expected to cost about the same. To be conservative for the cutter, it was assumed that a blender would cost at least as much and probably more. Its price was equated to that of a similar size blender ( 5,000). In place of an anchor-type agitator, the costs for a propeller-type agitator was used. Similarly, it was assumed that an epoxy-lined tank would cost the same as a rubber-lined tank. 

Add the Morpholine and mix with a propeller-type agitator. Formulation E2-7248... 

A liquid is stored in a 10m3 tank (cylinder with vertical axis, diameter 2m). The lower part of the tank is equipped with a jacket (height 1 m). At the storage temperature of 30 °C, the liquid shows a heat release rate of 15mWkg 1. The tank is stirred with a propeller type agitator. 

Flow patterns in a mechanically agitated reactor with disk turbine, pitched-blade turbine, and propeller types of agitator are schematically illustrated by Joshi et al. (1982). The flow pattern in the presence of gas is described later in the section on slurry reactors. In each of these cases, the dimensionless velocity profile with respect to the impeller tip velocity has been found to be independent of the impeller speed and has shown slight dependence on the impeller diameter. 

The stirrer, which may be of either the half-roimd or the propeller type, must be of heavy construction and must be driven by one of the more powerful laboratory stirring motors. Agitation must be maintained throughout the reaction period. 

These tanks should be equipped with sweep-arm agitators rotating at approx 50 rpm or slow-speed, large-bladed, propeller-type agitators. Filter aid, once in suspension, is easy to keep in suspension. Tanks should have dished, coned, or slanted bottoms so that all liquid can be drained from the tank and so that in the precoat operation a minimum heel can be maintained during circulation of liquid between the precoat tank and the filter. 

The laboratory method was scaled up to the minimum amount that could be successfully processed in a 10-hter stainless-steel kettle (Figure 2). fitted with a 12-cm propeller-type agitator and a 2.5-cm-wide baffle. The reactants were 2.00 liters of filtered 2 N (340 g/liters) silver nitrate solution, 2.00 liters of filtered 2N (130 g/liters) sodium azide solution, 1.07 liters of filtered reagent-grade (28%) ammonium hydroxide. 

Fig. 10-6. Oil-hydrogenating unit with internal heating and cooling coil, gas-circulating pump, oil- and catalyst-circulating pump, and propeller-type mechanical agitator.

In a 3-liter, three-necked flask fitted with a propeller-type agitator, thermometer, reflux condenser, and inlet and outlet tubes for purified nitrogen which are fitted with bubble counters, a solution of 600 gm of purified vinyl acetate and 900 gm of ethylene dichloride is heated to reflux with stirring while a nitrogen flow of 7 ml/min is maintained. The heat is adjusted to maintain a reaction temperature of 70°C. At that temperature, 1.5 gm of dibenzoyl peroxide is added and the nitrogen flow is redueed to 5 ml/min. Within approximately 5.5 hr, approximately 85% of the monomer is converted to polymer. 

Pettelkau and Ehrig [36] also described an up-flow reactor for chloroprene emulsion polymerization. Their reactor is operated full with a bottom propeller-type agitator that is mounted at an angle to achieve good mixing without internal baffles. Non-geometric scale-up with large H/D ratios are used to increase heat transfer area in the jacket. 

As mentioned earlier, these impellers operate at relatively high speeds and are effective only in low to medium viscosity liquids. In most cases, the main flow in the vessel tends to be transitional and/or turbulent. For shearthinning polymer solutions and particulate suspensions agitated by paddle, turbine and propeller type impellers, many correlations of varying complexity and form are available for the estimation of the outside film coefficient. One such correlation, based on wide ranges of conditions (400 < Re < 10 4 < Pr < 1900 0.65 < /ieff < 283mPa s), is due to Edney and Edwards [1976] ... 

Density with respect to the liquid (heavy lumps tend to settle down and will need suitably designed propeller type of agitator for proper dissolution). 

The sulphonic acid is introduced beneath the paste surface, near the propeller-type agitator. Through a pipe manifold process water and caustic are introduced beneath the paste surface, sufficiently far away from the impeller to avoid it being corroded due to strong pH fluctuations. 

The propeller-type agitator is the most common in the mining industry. Its design can be examined from various angles mechanical strength, speed of operation, hydrofoil shape of the blades, etc. The shaft is designed for the jamming condition or start-up in a settled tank. The main force is taken at 75% of the maximum radius blade span meas-... 

The stabihty of the emulsions further permits them to be compounded in simple Hquid-blending vessels by means of agitators, eg, marine-type propellers, paddles, or turbines. The adhesives can be adapted to any type of machine appHcation, ie, from spray guns to rollers to extmder-type devices. Different appHcators are fairly specific in their viscosity requirements, as are the various substrates receiving the adhesive. 

For agitator types of propellers, turbines with flat blades and paddles, 4 and a are 1.5 and 1.4, respeetively. The eriterion for Equation 7-92 is the absenee of any immobile solid on the bottom of the tank. 

These types of agitator are used in low-viscosity systems (ji < 50 kg m 1 s-1) with high rotational speed. The typical tip speed velocity for turbine and intermig is in the region of 3 m s 1 a propeller rotates faster. These impellers are classified as remote clearance type, having diameters in the range 25-67% of the tank diameter. 

The flow patterns for single phase, Newtonian and non-Newtonian liquids in tanks agitated by various types of impeller have been repotted in the literature.1 3 27 38 39) The experimental techniques which have been employed include the introduction of tracer liquids, neutrally buoyant particles or hydrogen bubbles, and measurement of local velocities by means of Pitot tubes, laser-doppler anemometers, and so on. The salient features of the flow patterns encountered with propellers and disc turbines are shown in Figures 7.9 and 7.10. 

A simple jacketed pan or kettle is very commonly used in the processing industries as a reaction vessel. In many cases, such as in nitration or sulphonation reactions, heat has to be removed or added to the mixture in order either to control the rate of reaction or to bring it to completion. The addition or removal of heat is conveniently arranged by passing steam or water through a jacket fitted to the outside of the vessel or through a helical coil fitted inside the vessel. In either case some form of agitator is used to obtain even distribution in the vessel. This may be of the anchor type for very thick pastes or a propeller or turbine if the contents are not too viscous. 

BROWN et al.i95) have given data on the performance of 1.5 m diameter sulphonators and nitrators of 3.4 m3 capacity as used in the dyestuffs industry. The sulphonators were of cast iron and had a wall thickness of 25.4 mm the annular space in the jacket being also 25.4 mm. The agitator of the sulphonator was of the anchor type with a 127 mm clearance at the walls and was driven at 0.67 Hz. The nitrators were fitted with four-bladed propellers of 0.61 m diameter driven at 2 Hz. For cooling, the film coefficient hb for the inside of the vessel was given by ... 

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