A wet solid is dried from 40% to 10% moisture under
constant drying conditions in 5 hours. If
the equilibrium moisture content is 0.0416 kg moisture/kg dry solid
and the critical moisture
content is 14%, how long will it take to dry from 40% to 5%
moisture under the same conditions.
All percentages other than equilibrium moisture content are on wet
basis. Assume linear relation
between rate of drying and moisture content during falling rate
period.
In: Other
The two __1__ of energy for life on this planet are ultimately the photons from the __2__ and the __3__ from the __4__. Fill in the blanks
In: Other
Wind direction
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Kinetic energy is the energy of ...............................It is at a ................................when the planet is closest to the Sun. Gravitational potential energy is the...........................................It is a..................................when................................distance to fall, which is when a planet is ........................from the Sun.
The total orbital energy stays......................................................When one type of energy (such as kinetic) goes up, the other type (GPE), goes ...................................This implies that orbits don't .............................................
When you are capturing at the escape velocity, you are no longer travelling in a............................The minimum speed to escape depends on ..............................................and ..................................................
To capture something into orbit, you must lose kinetic energy. Three ways to make this happen are:
1: ....................................
2:.....................................
3:...............................................
The tides are caused by..................................................The side ............................................................to the Moon feels the ......................................pull
We get carried through tidal bulges because .................................., which gives us ..........................................high tides per day.
The Sun also creates tides. These are approximately ..........................as high as regular tides. A.................................................occurs when the Sun and Moon are lined up. This means we will have higher high tides and lower low tides. When the Sun and Moon don't line up, we get a .............................................tide. The high tides are not very high, and the low tides are not very low.
Tidal flexing causes ..............................................This friction converts....................to ..........................................., which causes..........................to slow down.
As the Earth's spin slows, the Moon's orbit .......................This means the Moon is............................This means that the Moon probably formed.....................................to the Earth. Some moons get a lot of....................................from tidal friction. In the case of lo, this cause a lot of .......................................on the surface.
In: Other
Fill in the blanks in the following table using the Porphyry Copper Deposit description as an example. To enter data, just click on the cell and start typing. The cell will stretch to fit your answer.
question is from introduction to mining 1
MI1033 - Introduction to Mining
Module #1, Unit #2 – Resources and Ore Deposit Formation
Deposit Type | Principal Ore Mineral(s) | Secondary Ore Mineral(s) | Name An Example of a Deposit and its Location | Grade And Tonnage Characterization Description | Typical Mining Methods | Size or Dimension of the Deposit | Shape of the Deposit | Style of Mineralization | Rock Types | Formation Description |
| Cu | Au, Ag, Mo | Pebble, Alaska | Large tonnage and relatively low grades | Surface methods and underground – Block Caving | Hundreds to thousands of meters in each dimension | Oval or spherical | Stockwork Veins | Light coloured Igneous Instrusions and surrounding country rock | Derived from hydrothermal Fluids near top of cooling magma body between 1-5 km depth. Fluids fill in cracks creating a stockwork vein system. |
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Use the terms: igneous, metamorphic, or sedimentary to fill in the following blanks.
Most of the Earth’s surface is visually made up of ______ rocks, while the volume of the Earth is mainly________ .
The rock cycle shows that all rocks are formed in an exact order.
| True |
| False |
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. A 0.65 specific gravity natural gas contains 10% nitrogen, 8% carbon dioxide, and 2% hydrogen sulfide. Brill and Beggs correlation can used in estimating the z-factor values accurately enough for many engineering calculations. Brill and Beggs’ z-factor correlation is expressed as follows: With your knowledge in computer literacy and information technology coupled with Matlab programming, develop either a Microsoft excel spreadsheet program or a Matlab script to compute the z-factor of the gas at initial pressure and temperature of 5,000 psia and 180 °F respectively. Your application should be able to compute the z-factor for the gas at varying temperature and pressure.
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An ideal Rankine cycle operates between the pressure limits of 15 MPa in the boiler and 50 kPa in the condenser. The boiler generates steam at a mass flow rate of 50 kg/s and it enters the turbine at a temperature of 1100 °C. a) Calculate the net output of the cycle b) Calculate the thermal efficiency of the cycle.
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1.) A fuel gas containing 95mol% methane and the balance ethane is burned completely in a furnace with 25% excess air (79mol% N2, 21mol% O2). The stack gas leaves the furnace at 900°C and is cooled to 450°C in a waste heat boiler. Assume a pressure of 1atm throughout the process.
(a) Draw a fully labeled flow diagram, and calculate the amount of heat (in kJ) that must be transferred from the gas in the waste heat boiler to achieve the cooling. Use a basis of 100mol of fuel gas. (Use Table B.8 for specific enthalpy values)
The waste heat boiler is a heat exchanger, where the stack gas is cooled via a stream of boiler feedwater at 40°C. This stream of liquid water is converted to steam in the process to be used in other applications.
(b) For the same basis as (a), how much saturated steam at 50 bar can be produced? Assume that the specific enthalpy of feedwater is the same as that of saturated water at the same temperature.
(c) Show that the assumption used in (b) is valid. (Hint: What is the difference between the specific enthalpy of the subcooled feedwater and saturated water at 40°C?)
(d) If a desired flow rate of steam of 1250kg/h is desired for use in other applications, what is the required feed rate of the fuel gas (in kmol/h)? What is the volumetric flow rate (in m3/s) of the gas leaving the boiler?
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What, if any, difference exists between Greenwich Mean Time (GMT) and Coordinated Universal Time (UTC)?
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What is meant by swooper versus basher style of writing?
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Drilling Course.
What are the disadvantages of adding solids to the water-based mud?
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Assuming a constant drying condition,a pile of meat wet solid was dried on a tray dryer.The thickness of material on the tray is 35.4 mm. Only top surface with an area of 0.45 m2 was exposed to drying. It took approximately 3.9 hours to dry 12.0 kg wet meat from its initial free moisture of 0.55 kg free moisture/kg dry meat to its critical moisture content of 0.22 kg free moisture/ kg dry meat. Evaluate the time to dry a pile of this material from X1 = 0.48 to X2 = 0.32 using the same drying conditions, with drying from top and bottom surfaces.
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Chlorides enter the great lakes from human activity, but the most important sources is from the salting of roads in the winter to make them safe for driving. High Chloride concentrations (salty water) are damaging to the aquatic ecosystem. If, the great lakes would have chloride levels of > 20 mg/L, why would this be a problem? What uses of the lakes might be threatened by such high chloride concentrations? How do you think the lakes will be changed as a result of such high chloride concentrations?
Suppose you are the chief environmental engineer in charge of the joint Canadian – U.S. great lakes water quality commission. You have to set water quality limits for chlorides, recognizing that the limits you set would be considerably less than 20 mg/L and that changes in human lifestyle would be needed if the chloride concentration is to remain below these standards. What type of decisions would you be making? (there may be more than one, and there is no “correct” answer to this question.
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