Tons per hour

Belt-conveyor scales determine the amount of material being conveyed on a belt. A section of belt is weighed by placing the belt support rollers on a scale the belt speed is also measured. Weight and speed data are suppHed to a controller which integrates them to arrive at a material flow rate, often stated in tons per hour. The controller may display a flow rate, shut the conveyor down when a predeterrnined amount of material has passed, or it may be used to maintain a specified flow rate. Accuracy is limited because of the number of detrimental influences involved, eg, variable belt tension. 

Pusher centrifuges require high feed concentrations to enable the formation of a sufficiently rigid cake to transmit the thmst of the piston. The diameters vary from 150 to 1400 mm, the stroke frequency from 20 to 100 strokes per minute, and the soHds handling capacities up to 40 metric tons per hour or more. 

Generally, as the product size becomes finer, the capacity of the separating device decreases. Thus, there are devices that can be fed hundreds of metric tons per hour (MTPH) and produce a 95% passing 50-p.m product but a device that produces 95% passing 5 p.m may have a capacity of ca 1 MTPH or less. 

The capacity of spray-dryiag towers is iafluenced by the formulation of the powder being produced. For large spray-dryiag towers, throughputs of up to 30 tons per hour can be expected. 

Fig. 9. Schematic steam balance where the numbers represent steam flows in metric tons per hour. See Table 3.

Table 3. Steam Balance, Flows in Metric Tons per Hour ...

Objective Determine the filter size and vacuum system capacity required to dewater 15 mtph (metric tons per hour) of dry sohds and produce a cake containing an average moisture content of 25 wt %. 

NOTE To convert inches to milhmeters, multiply by 25.4 to convert revolutions per minute to radians per second, multiply by 0.105 to convert gallons per minute to hters per second, multiply by 0.063 to convert tons per hour to kilograms per second, multiply by 0.253 and to convert horsepower to kilowatts, multiply by 0.746. 

T pe of particle charging Feed Separation T pe of separator Feed temperature, °C Feed. size, mm Feed rate, metric tons per hour per start d No. of stages of separation... 

To convert metric tons per hour per start to kilograms per second per start, miiltiplv l)v 0.2778. 

To convert inches to millimeters, multiply hy 2,54 to convert pounds to Idlo-grams, multiply hy 0,4535 to convert horsepower to Idlowats, multiply hy 0,746 and to convert tons per hour to kilograms per hour, multiply hy 907,... 

Fairfield Engineering Co. data in U.S. customary system. To convert cubic feet per hour to cubic meters per hour, multiply by 0.02832 to convert tons per hour to metric tons per hour, multiply by 0.9078 and to convert screw size in inches to the nearest screw size in centimeters, multiply by 2.5. 

Since this type of conveyor is available in only one standard size, its capacity is determined by the belt speed and the fixed cross-sectional area. Tons-per-hour capacity is figured by multiplying the bulk density in pounds per cubic foot by the speed in feet per minute and a constant of 0.0021. Power requirements are quite low and figured in the same way as those for conventional belt conveyors. 

An incinerator stack is emitting fly ash at a rate of 2 tons per hour. Natural processes arc capable of removing these particles from the affected gromid... 

Boilers with an aggregate not less than 200 tons per hour of steam being used wholly or in part for electricity generation. 

Solid fuel (or solid waste) at a rate of 1 ton per hour or more. This plant should be approved by the local authority prior to installation (this Section is now replaced by the Clean Air Act 1968, Section 3). 

Furnaces other than those burning solid fuel at a rate of greater than one ton per hour - the following classes, used for any purpose other than the incineration of refuse ... 

Sub-Section 3 enables an owner to serve a notice on the local authority requiring them to take the measurements that he would be required to obtain under Section 7 of the 1956 Act. The ratings of such furnaces shall be less than one ton per hour of solid fuel other than pulverized fuel or liquid or gaseous-fuelled furnaces with a rating of less than 28 million BTUs. 

In most problems, the concentration of contaminant is so small that there is virtually no difference between the concentration based on the mass flowrate of water and the mass flowrate of the mixture. However, it is important to be consistent and follow the convention given in Equation 26.1. The other point to note is regarding the units. It is convenient to define the flowrate in terms of metric tons (typically tons per hour or tons per day). It is also convenient to define the concentration in terms of parts per million (ppm). If the basic unit of flowrate is taken to be tons and concentration to be parts per million, then the mass load is measured in grams (typically grams per hour or grams per day). 

By applying nonlinear curve fitting, we obtained the fuel requirements for the two generators explicitly in terms of MW produced. For generator 1 we have the fuel requirements for fuel oil in tons per hour (jtn)... 

Processes have variable throughputs with minimum process throughput TPPmm and maximum process throughput TPP max on a tons per hour basis V r,. v e IP5. Minimum and maximum process throughputs bound the process quantity as illustrated in fig. 69. 

Input product quantities like raw material consumption rates can be variable depending on utilization of the resource. Input product quantities are determined by linear recipe function with the recipe factors ap and bP pt on a tons per hour basis V r,s,/> e IPU. This is a key issue of the production and the entire supply model including procurement is to decide on the variable raw material consumption rates in production. Both production and procurement planning are highly interrelated, i.e. high production rates determine the amount of raw material that has to be supplied. In the overall context of value chain optimization, production rates have to comply with decisions reflected by the sales model e.g. on spot sales quantities and prices. 

The relative simplicity of the gasification system enables its operation to be within the technical expertise of most operators who are experienced with conventional boilers and furnaces, and results in favorable project economics. Its modular design allows a wide range of scale-up or scale-down possibilities, so the systems can vaiy in size from about one ton per hour of residue to 20 tons per hour or larger, with the size being limited only by biomass availability. 

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