1ST LONG QUIZ Flashcards
Differentiate hard water with soft water.
Hard water contain objectionable amounts of dissolved salts of calcium and magnesium while soft water is free from dissolved salts such as calcium and magnesium.
How does ion exchange utilized in water softeners?
Ion exchange consists of removing hardness ions calcium and magnesium and substituting them with non-hardness ions such as sodium to be supplied by dissolving sodium chloride salt or brine.
Explain how sodium-cation-exchange process works in water conditioning.
Large calcium and magnesium ions displace smaller sodium (Na+) ions. The smaller sodium ions are employed to coat an exchange medium (natural “zeolites” or synthetic resin beads resembling wet sand) in the softener during the ion exchange process. When hard water flows through a water softener, calcium and magnesium ions are exchanged for sodium ions. Sodium ions are held loosely and are readily replaced by calcium and magnesium ions, which are bigger. This process results in the release of “free” sodium ions into the water. After the resins are exhausted, they can be returned to their original state and the process can be repeated.
Explain how hydrogen-cation-exchange process works in water conditioning.
The hydrogen-cation exchange process is quite similar to the sodium cation removal process, with the exception that all cations can be removed using exchange resins because they contain an exchangeable hydrogen ion.
What process in ion exchange in water conditioning serves as the most extensively utilized and cost-effective approach?
Regeneration with sulfuric acid
Explain how anion exchangers works in water conditioning.
Anion exchangers are made of two resin kinds, either highly basic or weakly basic, that remove strongly ionized acids, such as sulfuric, hydrochloric, or nitric, and weakly ionized acid types, such as silicic and carbonic.
Explain how lime-soda process works in water conditioning.
It is quite useful for treating large quantities of hard water. When lime (CaO) and sodium carbonate (Na2CO3) are added to hard water, calcium carbonate, and magnesium hydroxide are precipitated. The required quantities of the two compounds can be simply estimated based on the water analysis and stoichiometry of the reactions. The lime soda method precipitates hardness from solution using lime, Ca(OH)2, and soda ash, Na2CO3.
Explain how cold lime process works in water conditioning.
It is treated with lime or a mixture of lime and soda ash, which interacts with the hardness and alkalinity of the water to generate insoluble compounds. After the chemicals precipitate in water, sedimentation/clarification eliminates them. It is used when the mineral level of the source water
ranges between 150 ppm and 500 ppm .
Explain how hot-lime soda process works in water conditioning.
It is similar to the cold lime process, with the addition of steam to the mixed tank. Precipitation is more rapid and utilized exclusively for boilers. Magnesium water hardness can be eliminated entirely, while calcium water hardness may remain at a very low level.
Explain how phosphate conditioning works in water conditioning.
Scale formation can be avoided in high-pressure boilers by adding sodium phosphate, which interacts with hardness-causing substances in the water to generate a soft, non-adherent sludge of calcium and magnesium phosphates that can be removed via blow down.
How phosphate conditioning differs from lime process?
Phosphate conditioning involves an internal treatment method while lime process involves an external treatment method.
Explain how to remove colloidal and ionic silica in water conditioning.
A strong base anion exchange resin is created to reduce ionic silica to parts per billion (ppb) levels. Ionic Silica is a weak acid, which can be removed entirely by a cycle based on hydroxide. The colloidal silica can be removed by a fine mechanical method such as ultrafiltration.
It is the removal of dissolved gases from boiler feedwater by mechanical means, to avoid corrosion.
Deaeration
Chemical process equation for rusting.
O2 + Fe + H2O -> Fe2O3H2O
How deaeration works in water conditioning.
Dissolved oxygen in boiler feedwater causes severe corrosion damage. It adheres to metal piping and other equipment, and it creates oxides (rust). When dissolved carbon dioxide mixes
with water, carbonic acid is produced, which worsens corrosion.
It refers to any treatment method that removes minerals from water. However, it is mainly reserved for ion exchange (IX) processes designed to remove ionic mineral pollutants to an almost complete degree.
Demineralization or deionization.
It is the process of removing soluble salts from water in order to make it appropriate for drinking, irrigation, and industrial applications.
Desalination
Give two types of desalination techniques.
- Membrane
▪ reverse osmosis
▪ nanofiltration
▪ electro-deionization
▪ electrodialysis - Thermal Processes
▪ multiple-effect distillation (MED)
▪ multi-stage flash evaporation (MSF)
▪ vapor compression
It is the process of removing undesired chemicals, biological contaminants, suspended particles, and gases from water. The purpose is to create water appropriate for a variety of applications.
Water purification
Explain how purification works in water conditioning.
Physical techniques such as filtering, sedimentation, and distillation are employed, as well as biological processes such as slow sand filters or biologically active carbon, chemical processes such as flocculation and chlorination, and electromagnetic radiation such as ultraviolet light.
Enumerate 6 environmental protection throughout the year.
(1) London Convention of 1900
- Safeguard African wildlife
(2) 1933 London Convention
- Creating nature parks and protecting species in Africa.
(3) Stockholm Declaration (1972)
- Recognize the right to a healthy environment through 26 principles, many of which had a significant influence in the subsequent development of IEL.
(4) Rio Declaration (1992)
- The Precautionary Principle and Principle 10, which emphasizes the right to information, involvement, and justice in environmental problems.
(5) Kyoto Protocol (1997)
- The first international agreement to impose legally binding responsibilities for industrialized countries
(6) Paris Agreement (2016)
- Agreement that aims to prevent the average global temperature from increasing by more than 2°C relative to pre-industrial levels.
In 2020, about how many percent of wastewater in the Philippines is treated?
10%
How many percent of the total population in the Philippines is connected to a sewer network?
5%
About how many percent of families in the Philippines have sanitary toilet facilities?
76.8%
How many percent in the Philippines have access to piped sewerage systems?
10%
What are the methods for deactivating dangerous contaminants?
- Neutralization of acids or bases
- Oxidation of many chemicals
- Binding into an impermeable chemical matrix
- Incineration
- Pyrolysis
What are the common types of equipment for collecting tiny particulates?
- Baghouse filters
- Cyclones
- Scrubbers
- Electrostatic precipitators
How does sludge, one of the industrial solid waste, is treated in industries?
Sludge is dehydrated using centrifugation, filtering, and/or heating.
Incineration is banned in the Philippines because of R.A. 8749 or known as?
Clean Air Act
It is most widely used solid fuel, the world’s largest greatest deposit, low-cost source of heat and power, and can make specific aromatic and aliphatic chemicals.
Coal
What are the 5 common procedures for generating chemicals from coal?
- Gasification
- turns coal into a very hot synthesis gas - Liquefaction
- turns coal into liquid products resembling crude oil - Direct Conversion
- involves contacting coal directly with a catalyst - Co-production of Chemicals
- consists of pyridine, naphthalene, creosote oil, etc. - Co-production of Fuels
- burns coal to generate electricity, gasoline, etc.
Enumerate 6 types of coal.
- Peat
- Lignite
- Sub-bituminous
- Bituminous: (1) Smithing coal (2) Cannel coal (3) Coking coal
- Anthracite
- Graphite
It is not coal, but can eventually transform into coal under the right circumstances. It is an accumulation of partly decayed vegetation that has gone through a small amount of carbonization.
Peat
It is the lowest rank of coal. It has carbonized past the point of being peat, but contains low amounts of energy—its carbon content is about 25-35 percent. It comes from relatively young coal deposits, about 250 million years old.
Lignite
It is about 100 million years old. It contains more carbon than lignite, about 35-45%. It is also considered “brown coal” along with lignite.
Sub-bituminous
It is formed under more heat and pressure, and is 100 million to 300 million years old. It contains about 45-86 percent carbon.
Bituminous
Give 3 types of bituminous coal.
(1) Smithing coal
- has very low ash content, and is ideal for forges, where metals are heated and shaped.
(2) Cannel coal
- was extensively used as a source of coal oil in the 19th century. Coal oil is made by heating cannel coal with a controlled amount of oxygen, a process called pyrolysis.
(3) Coking coal
- is used in large-scale industrial processes. The coal is coked, a process of heating the rock in the absence of oxygen. This reduces the moisture content and makes it a more stable product. The steel industry relies on coking coal.
It is the highest rank of coal. It has the most amount of carbon, up to 97%, and therefore contains the most energy. It is harder, denser, and more lustrous than other types of coal.
Anthracite
It is an allotrope of carbon, meaning it is a substance made up only of carbon atoms and it is the final stage of the carbonization process.raphite.
Graphite
How pyrolysis or carbonization works in manufacturing products using coal.
The process of heating coal in the absence of air/oxygen to obtain products (coal tar, coke, coal gas, and ammoniacal liquor) which are determined by the temperature and the type of coal used.
What are the two types of carbonization of coal? Differentiate the two.
(1) Low-temperature carbonization
- The yield of liquid products is larger than the yield of gaseous products. Soft coke is obtained and is used for dometic purpose. No smoke is produced.
(2) High-temperature carbonization
- The yield of gaseous products is larger than the yield of liquid products. Hard coke is obtained and is used for metallurgical purpose. Smoke is produced.
It is the process of converting coal into a graphitizable substance known as coke.
Coking of coal
What are the two main types of coking procedure? Differentiate the two.
(1) Beehive coking
- The old and primitive method of securing coke for metallurgical purposes.
(2) By-product coking
- A 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.
Explain how beehive coking process works.
The coal is scattered across the floor after being inserted through a hole in the dome. The gases emitted by the coal mix with the air entering through the discharge door at the top and burn. Combustion products exit through the top of the oven.
Explain how by-product coke making is operated.
For bulk density control, selected coals are blended, crushed, and oiled. 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. The coal is carbonized in a reducing atmosphere, and the off-gas is collected and transferred to a byproduct recovery plant. The hot coke is discharged, quenched, and shipped to the blast surface.
Enumerate 5 by-product recovery of coal chemicals.
- Tar. The gas from the coke oven is sprayed with liquor ammonia in a tower. Tar and dust are gathered in the tank below, which is heated by a steam coil in order to recover the ammonia that has been sprayed.
- Ammonia. The gases are then sprayed with water as they pass through another tower. Ammonia gets converted to NH4OH.
- Naphthalene. The gases are sent through another tower, this time with cooled water sprayed on them. The naphthalene is condensed here.
- Benzene and other aromatic compounds. The gas is then sprayed with creosite oil as it passes through the next tower. The oil is dissolved in benzene and other aromatic chemicals, which are then recovered.
- Hydrogen sulphide. The gas is then sent through a purification chamber.
It is a complex mixture of polynuclear aromatic compounds and a by-product of the coal pyrolysis.
Coal tar
Explain how the distillation of coal tar works.
Coal tar is distilled using the fractional distillation method. The process of fractional distillation of tar refers to the separation of components in a chemical mixture using the difference in their boiling points.
- Benzols, naphtha, creosotes, naphthalene, anthracene, carbolic and cresylic acids, pyridine, and pitch are all produced by distilling coal tar.
What are the three purpose of tar distillation.
- dehydrate the tar in the dehydration column
- remove the pitch from the dehydrated tar in pitch column
- separate tar oils in fractionating column
Flammable gases that burn using air or oxygen to produce heat make up a family of gases.
Fuel gas
What are the three classifications of fuel gas? Define each.
(1) Naturally occurring gases
- gases that are extracted directly from natural wells or can be obtained as a product of another process like refining.
(2) Synthesized gases
- mainly manufactured from other sources such as liquids/solid, fuel or water.
(3) By-products
- gases produced mainly after combustion of gases like specific coal processing or utilization reactors.
It is a combustible gas consisting of non-hydrocarbons and hydrocarbons and it is a fossil fuel energy source.
Natural gas
What are the three classifications of natural gas location?
(1) Conventional gas
- natural gas that can be extracted as it moves into large fractures and crack between layers of overlying rock.
(2) Unconventional Gas
- ‘tight gas’ or ‘shale gas’ that is located within tight pore
spaces and on gas that is trapped on ice on the seafloor
(gas hydrates).
(3) Associated Gas
- gas dissolved in oil; natural gas pressure that is applied to the underground oil reservoir frequently acts as the force
that propels oil to the surface.
Where is the major producer of natural gas in the Philippines?
Malampaya gas field in Palawan
Explain the 4 steps how natural gas is processed and purified.
(1) Oil and Condensate Removal
- Raw natural gas are dissolve in oil when extracted. The separation of oil and natural gas can be separated on their own due to the decrease in pressure. In most cases, conventional separators use gravitational separation techniques. For some cases, when wells produce high pressure gas and light crude oil or the condensate, LTX or the low temperature separator is employed. This separator utilizes pressure differentials to cool down the wet natural gas and separate the oil and condensates.
(2) Water Removal
- This step requires “dehydrating” the natural gas, which often entails either of the next two procedures - absorption and adsorption. Absorption occurs when water vapor is taken out by a dehydrating agent. Adsorption on the other hand happens when the water vapor is condensed and is collected on the surface of a solid desiccant.
(3) Separation of natural gas liquids (NGLs)
- Natural Gas Liquids (NGLs), which are valuable as separate products, make up a significant portion of natural gas that is obtained directly from a well. When heavier hydrocarbons are present, an absorption method is employed which utilizes NGL absorption tower and solvent regenerator, while when lighter hydrocarbons are presented, cryogenic expansion is utilized which uses mechanical refrigeration and a very low
temperature of gas stream.
(4) Sulfur and carbon dioxide removal
- Removing hydrogen sulfide and other sulfides in a gas is
necessary because it might cause a corrosion problem, but since the oxides of sulfur formed during the combustion process would affect the flow of gas consumers. In addition,
the sulfur compounds, more specifically H2S and S, have an efficient commercial value since these can be employed as a source of SO2 to produce sulfuric acid.
Hydrogen sulfide (H2S), which exists as sulfur in natural gas, is typically regarded as sour if it reaches how much mg of H2S per cubic meter of natural gas?
5.7
What does “Sweetening” of the gas mean?
It is the process of eliminating carbon dioxide and
hydrogen sulfide from a stream of natural gas using amine solution.
Explain how solid bed process works in separating acid gases from natural gas?
This procedure separates the acid gases from the gas stream and traps them in a fixed bed of solid particles.
Explain how liquid bed process works in removing hydrogen sulfide from natural gas?
The procedure makes use of a continuous contactor of some kind, like a packed tower or bubble-cap tower, where the gas flows up counter-current to the flow of the solution.
What are the two classifications of liquid bed process? Differentiate the two.
(1) Non-Regenerative processes
- utilized when (hydrogen sulfide (H2S) quantities are small or when residual H2S are cleaned after the removal of bulk volume.
(2) Regenerative process
- the purification for this process is affected by scrubbing the gas with a diluted solution of sodium carbonate (3 to 3.5 percent). The treatment removes all H2S, together with any hydrogen cyanide and some CO2 that s present from the gas.
It is a synthetic gas that is a combination of combustible gases usually composed of carbon monoxide and hydrogen and methane. It is described as a fuel gas mixture and is a product of the gasification process of a carbon-containing fuel.
Coal gas
Enumerate 3 classifications of coal gas.
- Low-heat-content syngas
- heating value of below 7 MJ/ m3 - Medium-heat-content syngas
- heating value of between 7 and 15 MJ/m3 - High-heat-content syngas
- heating value of 37 MJ/ m3
It is a thermochemical process of converting carbonaceous material such as a coal into a fuel - such as synthesis gas.
Gasification
It is often called blue gas because of the color of the flame when it is burned is used in the production of hydrogen.
Water gas
*Equation: C(amorph) + H2O(g) −−> CO(g) + H2(g)
What are the two main elements in producing blue gas?
The “run” and “blow” where the two main elements involved in producing water gas, and they each functioned in turn to create the gas in a cyclical pattern.
(1) During the blow period, air is employed with the use of fans into the base of the fuel bed. This provides oxygen, allowing the fuel to combust and heat the generator.
(2) During the run period, a steam was introduced into the generator to react with carbon. As the run proceeds, the fuel bed started to cool, the carbon dioxide produced and inert substances are increased, reducing the heating quality.
It is a type of fuel gas that is produced when air and steam is employed to a heating bed of coal. The focus is towards an incomplete combustion, to maximize the formation of carbon monoxide and minimize the formation of carbon dioxide.
Producer gas
is a fuel gas consisting of volatile hydrocarbons and it is a byproduct of the production of both crude oil refining and natural gas processing.
Liquified Petroleum Gas (LPG)
What are the 5 properties of industrial gases?
- Gaseous at room temperature and pressure
- Low molecular weight
- Requires proper handling and storage
- Element, compound or mixtures
- Distinct chemical properties
A measure of how readily a substance undergoes a chemical reaction.
Reactivity
Quality of being unreactive with other chemical compounds.
Inertness
An important heat-trapping gas, or greenhouse gas, that comes from the extraction and burning of fossil fuels (such as coal, oil, and natural gas), from wildfires, and from natural processes like volcanic eruptions.
Carbon dioxide
Chemical reaction for concentrating CO2
Na2CO3 + CO2 + H20 = 2NaHCO3
- = means reversible rxns
What do you call the reaction for concentrating CO2 that involves the use of hot, concentrated potassium carbonate solution, and ethanolamine solution?
Absorption Reaction
A process in which sugars are transformed into a new product through chemical reactions carried out by microorganisms.
Fermentation
Chemical Reaction of Fermentation
glucose (with yeast) -> ethanol + carbon dioxide
True or False: A major source for deriving hydrogen is from carbonaceous materials.
True