First Long Quiz Flashcards
1
Q
How do you define hardness traditionally?
A
The measure of water’s capacity to react with soap.
2
Q
Hardness is measured often in terms of what?
A
Calcium carbonate equivalent per liter
3
Q
State the range of water hardness according to calcium carbonate equivalence.
A
60 mg/L below - soft
60-120 mg/L - moderately hard
120-180 mg/L - hard
180 mg/L above - very hard
4
Q
What is carbonate (temporary) hardness?
A
contains calcium and magnesium carbonates that can be precipitated by heating
5
Q
What is non-carbonate (permanent) hardness?
A
contains magnesium and calcium in the forms of chlorides and sulfides that cannot be remove by simple boiling
6
Q
Who patented the lime process that was able to remove carbonate hardness?
A
Thomas Clark
7
Q
Who developed the use of soda ash for the elimination of noncarbonate water hardness?
A
Porter
8
Q
Who commercialized zeolites for water-softening uses?
A
Robert Gans
9
Q
Why is drinking hard water considered advantageous?
A
calcium and magnesium in hard water have a dose-dependent preventive impact against cardiovascular disease
10
Q
Give some water conditioning methods.
A
- Ion Exchange (Sodium-cation exchange process, hydrogen-cation exchange process, regeneration with sulfuric acid, anion exchangers)
- Lime-Soda Process (Cold-lime process, Hot-lime process)
- Phosphate Conditioning
- Silica Removal
- Deaeration
- Deminirelization and Desalination
- Purification
11
Q
How is Ion exchange used in water conditioning?
A
Ion exchange consists of removing hardness ion calcium and magnesium and substituting them with non-hardness ions such as sodium usually supplied by sodium chloride salt or brine.
12
Q
Explain the hydrogen-cation exchange process for water conditioning.
A
This process es able to remove all cations using exchange resins because they contain an exchangeable hydrogen ion.
13
Q
What is the most extensively utilized and cost-effective approach for water conditioning under the ion exchange process?
A
Regeneration with Sulfuric Acid
14
Q
Explain the anion exchangers
A
These are made of two resin kinds, either highly basic or weakly basic.
15
Q
What is the Lime-Soda Process?
A
This procedure is now obsolete. It uses lime and soda ash to precipitate hardness from the solution.
16
Q
Explain the cold-lime process
A
Also known as Clark’s process. It interacts with the hardness and alkalinity carried under room temperature. (25-30 deg C)
17
Q
What are the five treatment processes involved in Cold-lime processes?
A
- Chemical pre-treatment
- Clarifying
- Re-carbonation
- Filtering
- Sludge Treatment
18
Q
Explain the hot-lime process
A
Reactions occur at temperatures close to the boiling point of water (100-120 deg C) with the addition of steam to the mixed tank. Precipitation becomes more rapid and efficient than cold lime soda.
19
Q
Explain how phosphate conditioning
A
This method can prevent scale formation on high-pressure boilers by generating a soft- non-adherent sludge of calcium and magnesium phosphates that can be removed via blowdown.
20
Q
Explain how Silica Removal is used for water conditioning.
A
Since silica causes precipitation and forms a glassy layer on turbine blades, it decreases the turbine’s efficiency. Hence, it is removed by using a strong base anion exchange resin to reduce ionic silica.
21
Q
What are the 2 forms of SIlica in water?
A
Ionic silica and colloidal silica
22
Q
Explain how deaeration is used for water conditioning.
A
Since dissolved oxygen creates rust and corrosion it is removed by deaeration, which is the process of removing dissolved gases from boiler feedwater by mechanical means to avoid corrosion.
23
Q
What are the three design criteria that must be adhered to for any deaerator?
A
- The entering feedwater must be heated to the full saturation temperature.
- The hot feedwater must be stirred mechanically.
- A sufficient amount of steam must be passed through the water in both the spray section and the tray section to remove the gases.
24
Q
Differentiate demineralization from desalination.
A
Demineralization is a type of water purifying technique that removes minerals from water. Desalination, on the other hand, is the process that removes soluble salts from water.
25
What are the two primary desalination techniques? (Define them)
1. Membrane desalination - uses osmosis to remove salt and other contaminants
2. Thermal desalination - purifies water by evaporating and condensing
26
Explain what is purification in water conditioning.
Purification is the process that removes undesired chemicals, biological contaminants, suspended particles, and gases from water.
27
Give some physical techniques in purification.
filtering, sedimentation and distillation
28
Give some biological processes in purification.
slow sand filters and biologically active carbon
29
Give some chemical processes in purification.
flocculation, chlorination and electromagnetic radiation
30
Give some membrane desalination techniques
reverse osmosis, nanofiltration, electro-deionization and electrodialysis
31
Give some thermal desalination techniques
multiple-effect distillation (MED), multi-stage flash evaporation (MSF) and vapor compression
32
Define what an open system is in energy conservation.
A cycle that begins with an environmental balance but ends with an unbalanced environment. This cycle consumes resources and produces waste.
33
Define what a closed system is in energy conservation.
It is the closed cycles of resources that is the energy system sustainability model. It is an energy system without waste or resource consumption.
34
Give some primary energy sources
Conventional Energy Sources (CES), Nuclear Power, and New and Renewable Energy Sources (NRES)
35
What do you mean by conventional energy sources (CES)?
it is the most extensive use and has a well-established structure.
36
Give some examples of conventional energy sources
petroleum, coal, natural gas and hydropower
37
What do you mean by nuclear power as a primary energy source?
It is well established but has many issues. Its major use is limited to the production of electric power, naval propulsion or space utilization.
38
Give some sources of nuclear power
uranium, thorium, hydrogen, lithium, and natural radioisotopes
39
What do you mean by New and Renewable Energy sources?
This type of energy source is available in nature in a wider diversity than commercial sources.
40
Give some sources of new and renewable energy sources
For thermal energy: sunlight, endogenous fluid, and the sea thermal gradient
For chemical energy: wood, biomass energy crops, sea's saline gradient, bituminous schists, and oil sands.
41
Give some examples of electric heating devices.
Portable Electric Heating Devices, Radiant Heating Panels, electric baseboard heating, and unit and wall heaters
42
Give some types of furnaces.
Upflow, Low-boy, downflow, and horizontal furnaces
43
What is an up-flow furnace
It stands vertically and needs headroom. It takes in cool air from the rear, bottom, or sides near the bottom. It discharges hot air out of the top
44
What is a Low-Boy furnace?
Its air intake and discharge are both at the top.
45
What is a downflow furnace?
Also referred to as the counterflow furnace, where its air intake is at the top and discharge is at the bottom
46
What is a horizontal furnace?
Positioned on its side where its air intake is at one end and its discharge is at the other.
47
Give the formula of a perfect combustion
CH4 + 2O2 = CO2 + 2H2O + HEAT
48
What is a boiler?
An appliance that heats water using oil, gas, or electricity as the heat source.
49
Define refrigeration
The process of removing heat from a place where it is not wanted and transferring that heat to a place where it makes little or no difference.
50
What are the directions of heat?
Hot to cold
51
What are the four major components that make up a mechanical refrigeration system?
evaporator, compressor, condenser and the refrigerant metering device
52
Explain what an evaporator does on a refrigeration system
The evaporator absorbs heat into the system. It is able to absorb heat because the temperature of the coil is lower than the temperature of the medium being cooled.
1. absorbs heat from the medium being cooled
2. allows the heat to boil off the liquid refrigerant to a vapor in its tubing bundle
3. allows the heat to superheat the refrigerant vapor in its tubing handle
53
Explain what a compressor does on a refrigeration system
It pumps heat through the system in the form of heat-laden refrigerant. It can be considered a vapor pump. It is able to reduce and increase pressures which causes the refrigerant to flow.
54
What are the most common compressors used in residential and light commercial air-conditioning and refrigeration?
reciprocating, rotary and scroll
55
Explain what a condenser does on a refrigeration system.
It rejects both sensible and latent heat. It receives hot gas from the compressor through the hot gas line.
56
State the important things that happen to the refrigerant in the condenser.
1. Hot gas from the compressor is transformed into a condensing temperature. (Sensible heat Transfer)
2. Refrigerant is condensed from vapor to liquid (Latent heat transfer)
3. the liquid refrigerant temperature may then be lowered below the condensing temperature or subcooled.
57
Give some examples of renewable resources
solar power, hydropower, Ocean thermal energy plant, wave, tidal, wind, biomass, biogas, and geothermal
58
Give an example of a power plant in the Philippines
Helios Solar Power Plant and Malaya Thermal Power Plant
59
Give an example of a hydropower plant in the Philippines
Binga Hydropower Plant
60
Give an example of a wind power plant in the Philippines
Ilocos Norte's Burgos Wind Farm
61
Give an example of a Biomass power plant in the Philippines
San Carlos BioPower
62
Give an example of a Biogas power plant in the Philippines
Malitbog Geothermal Power Station
63
What are some Non-Renewable Resources?
- Solid Fuels (Coal and Coke)
- Liquid Fuels (Fuel Oils, Tar Sands, Shale oil)
- Gas Fuels ( Natural Gas and Manufactured Gas)
- Nuclear Energy (Nuclear Fission and Nuclear Fusion)
64
Differentiate nuclear fission and nuclear fusion
Nuclear Fission occurs when a neutron slams into a larger atom forcing it to split, while nuclear fusion is where two light nuclei merge to form a heavier nucleus
65
What are fuel cells?
It works like batteries but does not run down or need recharging.
66
What is Cogeneration?
The simultaneous production of electricity and useful heat
67
Give an example of a Philippine cogeneration power plant
Mariveles Cogeneration Power Plant
68
What are the requirements for refrigerants?
1. Its vapor pressure must be greater than the atmospheric pressure to avoid air leaks.
2. Its vapor pressure at condenser temperature should not be unduly high due to cost- issues.
69
Give some common refrigerants.
R-134A (1,1,1,2- Tetrafluoroethene), R-402, R-404A
70
What is coke?
The first used coal with few impurities and high carbon content
71
Define what a coal is.
It is made up of carbon-based compounds where various processes can be done to generate chemicals derived from this.
72
Give the types of coal enumerated by Nat Geo
Peat, Lignite, Sub-bituminous, Bituminous, Anthracite and Graphite
73
What is a Peat?
An accumulation or partly decayed vegetation that has gone though small amount of carbonization.
74
Define Lignite
Has the lowest rank among other coal. Comes from relatively young coal deposits
75
Define Sub-bituminous coal
Considered "brown coal" along with lignite but it contains more carbon than it. Mainly used as fuel for generating electricity.
76
Define Bituminous coal
Formed under more heat and pressure. And is divided into three major types:
1. Smithing coal - has a very low ash content
2. Canned coal - extensively used as a source of coal oil.
3. Coking coal - used in large-scale industrial processes.
77
Define Anthracite coal
the highest rank of coal. Has the most amount of carbon therefore contains the most energy.
78
Define graphite coal
An allotrope of carbon which means that it is only made up of carbon atoms
79
What are some common procedures for generating chemicals from coal and define them.
1. Gasification - turns coal into a very hot synthesis gas
2. Liquefaction - turns coal into liquid products resembling crude oil.
3. Direct Conversion - involves contacting coal directly with a catalyst.
4. Co-production of chemicals
5. Co-production of fuels
80
This is also called destructive distillation
Carbonization, pyrolysis of coal lignite, and carboniferous shales
81
Give some products of destructive distillation of coals.
coal-tar aromatics, benzene and homologs, naphthalene, anthracene, phenanthrene
82
Give some products of reduction and refining of ores
iron, ferro alloys, aluminum, magnesium
83
Give some products of gasification of coal
coal gas, blue water gas, producer gas, peak gas, synthesis gas, CO2 liquid and dry ice
84
Give some products of combustion for comfort heating and power combustion of coals
electric power utilities, comfort heating, retail deliveries, fly ash, sintered ashes
85
Give some products of combustion for the process heating of coal
heat for manufacture of lime, cement, ceramics, steel and rolling mills
86
Give some products for the reduction of coals
sodium sulfite, sodium sulfide, barium sulfide, phosphorus
87
Give some products of hydrogeneration and hydrogenolysis of coals
Fischer-Tropsh liquid fuels
88
Give some products of Demethylation of coal
benzene from toluene or xylene, naphthalene from methylnaphthalenes
89
Give some products of Hydrolysis of coal
mixed aromatics
90
Give some products of oxidation of coal
synthesis gas for Nh3, CH3OH, hydrogen, coal acids, carbon monoxide
91
Give some products of electrothermal of coal
graphite and electrodes, abrasives silicon carbide, calcium carbide, cyanamide, carbon disulfade
92
Give some products of sulfur recovery of coal
H2S from gas, pyrite from coal
93
Define the process of pyrolysis or carbonization
this is the process of heating coal in the absence of air/oxygen to obtain products that are determined by the temperature and coal type.
94
What is low-temperature carbonization?
the yield of liquid products is larger than the yield of gaseous products, soft coke is obtained and no smoke is produced
95
What is high-temperature carbonization?
the yield of gaseous products is larger than the yield of liquid products, hard coke is produced and smoke is produced
96
What is meant by coking coal?
the process of converting coal into a graphitizable substance known as coke
97
What are the two types of coking procedures and differentiate them
Beehive coking - an old and primitive method of securing coke
By-product Coking - method where blended-coal charge is heated on both sides so that the heat travels towards the center that produces shorter and more solid pieces of coke
98
State the process of coke-making operations
1. Selected coals are blended, crushed, and oiled,
2. The blended coal is fed into a series of slot-type ovens, each of which shares a heating flue with the oven adjacent to it.
3. Coal is carbonized in a reducing atmosphere, and the off-gas is collected and transferred to a byproduct recovery plant
4. The hot coke is discharged, quenched and shipped to the blast furnace
99
It is a by-product of coal pyrolysis
Coal tar
100
What is the purpose of tar distillation?
to dehydrate the tar in the dehydration column and separate tar oils in the fractionating column
101
Define fuel gas.
These are gases that burn using air or oxygen to produce heat.
102
Why can fuel gases be used as fuel?
Since they are essentially flammable gases they are able to generate heat and burn the air while maintaining sufficiently stable and standard temperature to permit storage longevity without risks of degradation.
103
What are most fuel gases composed of?
hydrocarbons, hydrogen, carbon monoxide and oil vapor forms
104
Where were the earliest gas leaks located?
Iran
105
Which country first recorded the use of combustible fuel gas
China
106
What are the classifications of fuel gas?
1. Naturally occurring gases
2. Synthesized gas
3. By-products
107
What is natural gas?
It is a mixture of non-hydrocarbon and hydrocarbon gases that are present in porous geologic formations beneath the earth's surface.
108
What are the major components oof natural gas?
methane, higher hydrocarbons (ethane, propane, butane, and pentane), water vapor
109
How is natural gas generated?
Since it is recognized as a fossil fuel, it is generated by decay of sea plants and creatures who died many hundred years ago.
110
What are the classifications of natural gas according to its location?
Conventional gas, unconventional gas, and associated gas
111
What is the overall chemical reaction of natural gas
CH4 + 2O2 = CO2 +2H2O
112
Give a natural gas field in the Philippines
Malampaya natural gas field
113
What are the main four steps in natural gas processing and purification?
Oil and condensate removal, water removal, separation of natural gas liquids, and sulfur and carbon dioxide removal
114
Differentiate absorption from adsorption
Absorption occurs when water vapor is taken out by a dehydrating agent. Adsorption on the other hand, happens when water vapor is condensed and is collected on the surface of a dessicant.
115
What are the two principal techniques for the separation of natural gas liquids?
absorption method and cryogenic expansion process
116
Give examples of acid gases.
carbon dioxide and hydrogen sulfie and other sulfur compounds (mercaptans)
117
What do you mean by sweetening the gas?
It is the process of removing carbon dioxide and hydrogen sulfide from a steam of natural gas
118
What are the four most commin process for solid bed process?
iron sponge, sulfa-treat, molecular sieve process and zinc oxide process
119
Give the chemical equation for non-regenerative process for liquid bed process
H2S + 2NaOH = Na2S + 2H2O
120
Give the chemical equation for regenerative process for liquid bed process
Purification: H2S + Na2CO3 = NaHS + NaHCO3
CO2 + Na2CO3 + H2O = NaHCO3
HCN + Na2CO3 = NACN + NaHCO3
Acidification: NaHS + NaHCO3 = Na2CO3 + H2S
121
What is gasification for fuel?
It is a thermochemical process of converting carbonaceous material such as coal into a fule - such as synthesis gas.
122
Give the chemical equation for methanation
CO + 3H2 = CH4 + H2O
CO2 + 4H2 = CH4 + 2H2O
123
What is producer gas?
This is a type of fuel gas that is prooduced when air and steam is employed to a heating bed of coal.
124
Give the following reactions that occur upon creating producer gas
C + O2 = CO2 (exothermic)
CO2 + C = 2CO (endothermic)
C + H2O = CO + H2 (endothermic)
C + 2H2O = CO2 + 2H2 (endothermic)
CO + H2O = CO2 +H2 (endothermic)
125
Give some natural gas applications
transportation, air conditioning, commercial, syntehtic production, electircity generation, cooking
126
What is solid bed process?
it separates the acid gases from the gas stream traps the acid gases in a fixed bed
127
Define industrial gases
These are a variety of gases that are produced for industrial purposes across a wide range of applications.
128
Give some common industrial gases.
carbon dioxide
hydrogen
oxygen
nitrogen
rar gases of the atmosphere (argon, neon, krypton, xenon)
helium
sulfur dioxide
acetylene
nitrous oxide
129
What are some properties of industrial gases?
gaseous at room temperature and pressure
usually tend to have low molecular weight
require proper handling and storage
can be an element, molecular compound, or even mixtures
have distinct chemical properties
130
Give some industrial gas companies in the Philippines
Air Liquide and Linde Engineering
131
Give some uses of Carbon Dioxide
In solid form: refregerating and freezing
In liquid form: carbonated beverages, fire-extinguishing material
In Gaseous form: reduce meal and food bacteria spoilage, Salicylic acid production, neutralizing alkalies, pH contorl for wastewater
132
What is fermentation?
a process in which sugars are transformed into a new product through chemical reactions carried out by microorganisms.
133
Give the chemical equation of fermentation
C6H12O6 = (yeast) 2C2H5OH + 2CO2
134
What is hydrogen?
colourless, odourless, tasteless, flammable gaseous substance that is the simplest member of the family of cemical
135
What properties of industrial gases are valued for?
coldness, reactivity and inertness
136
This method produces high-purity hydrogen and consists of passing direct current through an aqueous solutioon of alkali
Electrolytic method
137
give the reversible reaction for concentrating CO2
Na2CO3 +CO2 + H2O = 2NaHCO3
