54 Matching Annotations
  1. May 2022
    1. The cycle thermal efficiency (net power/heat input) for a supercritical vaporgenerator will exceed that for a subcritical cycle.
    2. A possible advantage to using the recuperative preheaters is that they reducethe heat load on the condenser and cooling tower. The lower capital cost for asmaller condenser and cooling tower must be compared to the extra cost for therecuperators; over the long haul, the resulting higher efficiency should meanlower operating cost
    3. The features that distinguish the Kalinacycles (there are several versions) from other binary cycles are as follows
    4. Given thesmall size of turbines using organic working fluids, practical considerations maylead to an alternative design using two separate turbines; see Figure 8.13.
    5. Dual-pressure binary plant: pressure-enthalpy process diagram
    6. Dual-pressure binary plant: Simplified schematic flow diagram
    7. The Carnot efficiency is the highest possible efficiency



    1. Supercritical cycles were found to have the lowest cost at allresources

      I wonder if this is true for any working fluid of the binary cycle. Or, this is just true for working fluids that are mixtures?

    1. Because the geothermal fluid leaves the heat exchanger at 196F in the mixture cycle, it could be used in heat exchange with a second working fluid mixture to obtainadditional work. Thus, a cascade system of two or more binary cycles could be developed to increase thework obtainable per pound of geothermal fluid passing through the geothermal power plant.
    2. Predictions of enthalpies, entropies, densities, dew points,bubble points, and vapor-liquid equilibria for the workingfluids were made using accurate correlation

      What does this mean?

    3. a situation which should minimize irreversibilities in the condenser
    4. The fact that the mixtureand the isobutane leave the turbine with 138 F and 167 Fsuper-

      It doesn't from the figure that I left at either of those temperatures.

    5. The geothermalfluid is considered to have the properties of supercooled liquidwater
    6. On the other hand, an essentially infinitespectrum of property behavior characteristics exists for mixtures and thus a mixture can in principle befound which matches the resource characteristics better than virtually any possible pure-fluid choice
    7. (a) Higher pressures can beused in the cycle, which increases the net cycle thermalefficienc
    8. the working fluid in the power production cycle (e.g.Rankine-type cycle) receives energy by heat transfer with the geothermal fluid
    1. The Young Natib volcanics are generallyexposed on the eastern portion of the area.This unit is composed of weakly consolidatedpyroclastic deposits and several small domessuch as Mts. Natib, Tiawir, Tirac and Tala,which are of hornblende andesitic compo-sition.



    1. Fault is a fracture or crack where two rock blocks slide past one to another.

      Would they suggest the presence of or increase the likeliness of aquifers?

    1. When magma comes near the earth's surface, it heats ground water trapped in porous rock or water running along fractured rock surfaces and faults. Hydrothermal features have two common ingredients: water (hydro) and heat (thermal).

      The subsurface presence of magma heats up groundwater collected within porous rocks. The conduction of heat through the rocks to the reservoir increases the temperature of the groundwater, which then can be drilled to harness the geothermal energy available from the hydrothermal system.

    1. Several structural featuressuggesting active volcanismthrough geologic time werefound to exist in the area. Themost conspicuous structuralfeature identified is the Natibcaldera structure which isestimated to have an area of38krn 2 (Figure 7).

      What are these structural features then? The presence of Natib volcanics should be among them.

    2. Table 4 shows the best guess value and the probabilitydistribution used in the stored heat and reserve estimate calculation. The simulation shows that Mt. Natibcan adequately supply the steam requirements of 10 to 15 MW. power plant for at least 20 years, a veryconservative estimate (Figure 20).
    3. It is possible that a convectivesystem may exist within the 20 km 2 area delineated by the YES measurements but outside the drilled areaor beyond the drilled depth
    4. Alteration mineralogy suggests a cooling system and limiteddownward percolation of meteoric water through faults (PNOC-EDC, 1990).
    5. Analyses of thermal waterreveals that they are of thesecondary neutral to slightlyalkaline S04- HC0 3-Cl andHCO,- CI type
    6. Silica and Na-K-Ca geothermometry predictssubsurface temperature of 168 and 189°C, respectively. On the other hand the Chloride -Enthalpy plotsprovide a relatively higher estimate of 210°C (PNOC-EDC, 1990).
    7. Thermal manifestations foundin the area are limited towarmlhot springs and alteredground. The thermal springsexhibited low flow rate ( 5: Ills)with neutral pH (7.5-8.0) werefound to be associated with theNW-SE and E-W faults andconfined within the calderastructure. Travertine andlimonite were noted to bedeposited around the springs
    1. The Philippines is one of the world's top producers of geothermal power, owing to its location along the Ring of Fire zone of Pacific volcanoes.[1]

      It's possibility that the Philippines may not have completely harnesses all available geothermal resources.

    1. Section 3.3 indicates that the parameters most correlated to suitable geothermal sites are carbon diox-307ide, earthquake density, elevation/depth, global heat flow, sediment thickness, and surface air temperature.

      How is carbon dioxide a parameter? Is it talking about the carbon dioxide emission of the plant?



  2. Apr 2022
    1. . Hence, the primary influentialparameters driving the dust collection systems are the velocities of the multiphase flow,and the pressure differentials [29,30,47,48], which are dependent of the velocities. Theydepend on the properties of the transporting fluid and of the transported particles.


    1. If a small quantity of a granular or powdered material is fed into the air in the pipeline at asteady rate, there will be an increase in the conveying-line pressure drop, if the mass flow rate of the airremains constant. The magnitude of this increase depends on the concentration of the material in theair. The increase in pressure drop, of course, will additionally depend on the size, shape, and density ofthe particles to be conveyed.

      The granular or powdered material must enter the stream at a steady rate. What then would be the effect if the rate were unsteady?

      Mills, David, Pneumatic Conveying Design Guide, 3rd Edition


    2. The axes are the same as those for the Geldart classification: density difference,which can be taken as particle density when the conveying medium is air, and mean particle size.

      Dixon's Slugging Diagram

      Pneumatic Conveying 3rd Edition https://drive.google.com/file/d/10jq3JXiX4RWqDgeJlD9FVFxL0k1VXgcj/view?usp=sharing

    3. classification can be used to a limited extent to identify which materials might be capable of densephase conveying

      *The Geldart Classification

      David Mills, Pneumatic Conveying Guide 3rd Edition


    1. The focus of the investigation has been on conveying velocity limits,



  3. Mar 2022
    1. Carbohydrates contain sugar, starch, hydrogen and oxygen – so they make a good fuel source in the right circumstances. When flour particles have a very large surface area and when suspended in air, in the right mix,they have a large supply of yet more oxygen.
    1. Drum or bag – a mechanism that requires replacement of the drum or bag that collects the matter.
    2. The air to cloth ratio is the amount of air that passes through a square foot of the filter. The lower the ratio, the higher quality of the filtration system's efficiency.
    3. Though a fan or blower may have a simple design, when installed in a dust collection system, several factors have to be considered. First of those factors is the volume of air that needs to be moved. This is measured in cubic feet per minute (CFM). The next consideration is the static pressure throughout the whole system. Other variables are the temperature, substances in the air, and the level of moisture.
    4. Dust collection systems have ductwork to draw in the air, an air purifier, and receptable.

      I don't notice this on COG dust collection system.

    1. According to some reports, food processing is the largest category for combustible dust explosions in manufacturing, accounting for almost 25 percent of incidents.

      I should ask about this in our interview.

    1. properly sized and manifolded to maintain a consistent minimum air velocity required to keep the dust in suspension for conveyance to the collection device.

      Didn't thought about this. I should take a look at the ducting from the ribbon mixer to the tanks collecting the dusts.

    2. Dust collection systems work on the basic formula of capture, convey and collect.

      I need to see how this system works in unison.

    3. It can be as simple as a basic pass-through filter, a cyclonic separator, or an impingement baffle.

      I remember Carlo mention an inertial separator last meeting. It his the same thing? If so, do they use this for food dusts as well?

    1. The amount of thrust produced by the rocket depends on the mass flow rate through the engine, the exit velocity of the exhaust, and the pressure at the nozzle exit. All of these variables depend on the design of the nozzle.
    2. which means that the Mach number is equal to 1.0 in the throat

      If the hot exhaust flow weren't choked at the throat, will the Mach number still be 1? But, why would the Mach number be 1 in the first in a choked flow?

    3. rocket thrust equation

    1. Atomization is the process of converting an analyte in solid, liquid or solution form to a free gaseous atom. It is the transformation of a bulk liquid into a spray of liquid droplets in a surrounding gas or vacuum.

      What's an analyte. Would atomization be associated with a phase change? Doesn't seem so. But how does this process of atomization occur?

  4. Nov 2020
    1. transmits energy to another part of the machine performing the work

      Seems straightforward enough. Would I call a wire a transmission apparatus since it conducts electricity?

  5. Oct 2020
    1. physical or chemical property of a material

      What is the physical property and chemical property of a thing that may lead to an accident?

    2. May lead to physical harm, damage to property, delay in operation or even death.

      An accident should immediately be defined in terms of these things.

      I could define an accident as an event that is not planed or desired that lead to physical harm, damage to property, delay in operation or even death.

    3. usually the result of contact of a body (or man) with a source of energy above the threshold limit of the body

      Gives a very broad send of why an accident occurs. If a police shot an assailant on the body, thus the body contacts a source of energy above threshold, will I then consider it an accident?

    1. hazards to which the workers are exposed

      This is either hazards that don't cause death, injury or illness (and I don't know what those are), or this is a case where workers are not free from hazardous conditions, since it was earlier stated that an employer shall furnish a place of employment free from hazardous conditions.

      I would have to question the earlier statement regarding freedom from hazardous conditions. What then is the extent of this freedom? Isn't it that when we say we are free of something, it is stated in the absolute sense. No one can be partially free from something. It is either he is free or he is not. Therefore, if there is no freedom from hazardous conditions, then this entails that a workplace will have its hazardous conditions. Freedom is not the goal nor is it a possibility.

      The purpose of the OSHS is to protect workers, why then is it demanded from the employer that they furnish a workplace free from hazardous conditions.

    2. furnish his workers a place of employment free from hazardous conditions

      Can a workplace be absolute free from hazardous conditions?

    3. which substantially comply with the provisions of this Standards

      It seems safety can't be approached by having a sense of what safe is.