Efficiency blower

Morrow, M. T. and VanDerpool, G., 1988, The Use of a High Efficiency Blower to Remove Volatile Chlorinated Organic Contaminants from the Vadose Zone — A Case Study In Proceedings of the National Water Well Association Second Outdoor Action Conference on Aquifer Restoration, Groundwater Monitoring and Geophysical Methods, Vol. Ill, Las Vegas, NV, pp. 1111-1135. 

Replace liquid-ring vacuum pumps with efficient blowers (equipped with water separators if water is being removed from the process). 

One design for a low temperature convection furnace shown in Figure 4 utilizes an external circulating fan, heating chamber, and duct system. The fan draws air (or a protective atmosphere) from the furnace and passes through the external heating chamber and back into the furnace past the work. This system minimizes the chance that the work receives any direct heat radiation. In theory it is less efficient because the external blower, heating chamber, and ductwork add external surfaces that are subject to heat losses. 

In air conditioning (qv) of closed spaces, a wider latitude in design features can be exercised (23,24). Blowers are used to pass room or cabin air through arrays of granules or plates. Efficiencies usuaHy are 95% or better. The primary limiting factor is the decreased rate of absorption of carbon dioxide. However, an auxHiary smaH CO2 sorption canister can be used. Control of moisture entering the KO2 canister extends the life of the chemical and helps maintain the RQ at 0.82. 

The steam balance in the plant shown in Figure 2 enables all pumps and blowers to be turbine-driven by high pressure steam from the boiler. The low pressure exhaust system is used in the reboiler of the recovery system and the condensate returns to the boiler. Although there is generally some excess power capacity in the high pressure steam for driving other equipment, eg, compressors in the carbon dioxide Hquefaction plant, all the steam produced by the boiler is condensed in the recovery system. This provides a weU-balanced plant ia which few external utiUties are required and combustion conditions can be controlled to maintain efficient operation. 

The overall benefits of this high efficiency combustor over a conventional bubbling- or turbulent-bed regenerator are enhanced and controlled carbon-bum kinetics (carbon on regenerated catalyst at less than 0.05 wt %) ease of start-up and routiae operabiUty uniform radial carbon and temperature profiles limited afterbum ia the upper regenerator section and uniform cyclone temperatures and reduced catalyst iaventory and air-blower horsepower. By 1990, this design was well estabUshed. More than 30 units are ia commercial operation. 

The pressure in the regenerator depends on several factors. As the actual inlet pressure is adjusted to 0.22-0.24 MPa, the expander matches the system, but power loss is considerable. The power consumption on the air blower may be reduced at the same time as the pressure in the regenerator is lowered. However, the overall efficiency of the power recovery system is not significantly affected. 

Centrifugal compressors usually have specific speeds of 1,500-3,000 rpm at the high efficiency point. The axial flow fans and blowers are high specific-speed wheels mixed flow units are lower and the centrifugal compressor wheels are the lowest in specific speed range because they have narrow impellers. 

A large fan or blower draws ambient air into the clean side of the filter bags. However, unless the air is properly conditioned by inlet filters, it may contain excessive dirt loads that can affect the bag life and efficiency of the dust-collection system. 

Figure 4-47. General efficiency curve applies specifically to involute entry cyclone dust separators. Courtesy of American Blower Div., American Radiator and Standard Sanitary Corp.

NOTE Soot blowers are typically employed only on WT boilers and may be regarded as appurtenances because boiler safety and reliability is directly related to the cleanliness of the heat transfer surfaces. Boiler performance and efficiency also depend on the same heat-transfer cleanliness factors. 

The furnace areas of WT boilers require the periodic deployment of retractable soot blowers to remove the buildup of soot and combustion products from water-wall tubes to maintain heat transfer and furnace cooling efficiency, as well as to minimize the interference of flue gas pathways. 

The higher pressure differentials allow longer and sometimes smaller lines than for fans. To estimate blower horsepower, use Equation 3-4 or 3-5. In lieu of manufacturer s data, use an adiabatic efficiency of 80% for initial work. 

This value must be increased to account for air leakage and for possible blockage of pipelines. If it is doubled and the blower has an efficiency of 70% the required BHP will be around 15. If the motor has an efficiency of 90% the power required for blowers B-601 and B-602 will be 12.5 kw. 

A surface effect (air cushion) vehicle measures 10 ft by 20 ft and weighs 6000 lbf. The air is supplied by a blower mounted on top of the vehicle, which must supply sufficient power to lift the vehicle 1 in. off the ground. Calculate the required blower capacity in scfm (standard cubic feet per minute), and the horsepower of the motor required to drive the blower if it is 80% efficient. Neglect friction, and assume that the air is an ideal gas at 80°F with properties evaluated at an average pressure. 

The air cushion car in Problem 29 is equipped with a 2 hp blower that is 70% efficient. 

An air ventilating system must be designed to deliver air at 20°F and atmospheric pressure at a rate of 150 ft3/s, through 4000 ft of square duct. If the air blower is 60% efficient and is driven by a 30 hp motor, what size duct is required if it is made of sheet metal ... 

As shown in Figure 2.25, it is more efficient to use a backing pump combined with one or two roots blowers (Fig. 2.27). The backing pump requires only 40 m3/h capacity, combined with a roots pump of 200 m3/h. This system evacuates the 1000 L also in 8 min down to 0.01 mbar, but below 0.1 mbar the system has a capacity of 200 m3/h or 2.2 10 3 g/s at 0.05 mbar. Such a pumping system is preferable for freeze drying compared with a large two-stage pump alone. 

Pressurised alkaline water electrolysis technology has been state-of-the-art for many years. The system efficiency of real electrolysers ranges from 62% to 70%, including all auxiliaries (AC/DC converter, pumps, blowers, controls, etc.) based on the lower heating value of hydrogen. 

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