Petroleum Processing and Chemical Engineering Principles
Differences Between Raw Material and Product, Residues, and Byproducts
Raw Material
Raw materials can be natural (wild type) or derived through basic chemical processes. For example, nitrogen can be considered a raw material, and air can be a source after liquefaction and distillation.
Byproduct
A byproduct is a secondary product obtained from a raw material during a process. It can often be used in other processes.
Residue/Waste
Waste is material that has no inherent value and requires management. Sometimes, waste can be recycled through specific processes, potentially serving as a raw material for energy production. However, recycling can be costly and may not always be feasible. When recycling is not possible, proper disposal methods are necessary.
Cracking and Fractionation
Cracking
Cracking is the chemical process of breaking large oil molecules into smaller, lighter molecules.
Fractionation
Fractionation is a physical process that separates the volatile components of a mixture based on their boiling points.
Renewable and Non-Renewable Energy
Renewable Energy
Renewable energy is derived from sources that can regenerate naturally, such as solar, wind, and hydro.
Non-Renewable Energy
Non-renewable energy comes from finite resources that deplete over time and cannot be replenished in the short or medium term, such as fossil fuels.
Solvay Process and Unit Operations
The user did not provide the chemical reactions for the Solvay process.
Understanding Oil
Oil, also known as petroleum, is a viscous liquid, typically ranging in color from yellow to dark brown or black, sometimes with green reflections. It has a characteristic odor and is less dense than water.
Oil is a complex mixture of hydrocarbons. Hydrocarbons with 1 to 4 carbon atoms are typically gaseous, those with 5 to 20 carbons are liquid, and those with more than 20 carbons are solid at room temperature.
The composition of crude oil varies depending on its source, but it generally contains 83-86% carbon and 11-14% hydrogen (not the other way around, as carbon is heavier than hydrogen).
A higher carbon-to-hydrogen ratio indicates a greater proportion of heavier components in the oil.
True or False
- America is a member of OPEC: False
- Ethane and propane have lower octane ratings than commercial gasoline: False
- Paraffinic oils produce more gasoline than asphalt: True
- API gravity is inversely proportional to specific weight: True
- API gravity is a reliable indicator of paraffinic and aromatic content: False (Watson characterization factor or correlation index are more reliable)
- The Watson characterization factor is lower for paraffinic crude oil than aromatic: False (paraffinic oils typically have higher values around 12, while aromatic oils have lower values around 10)
- Crude oil with low nickel, vanadium, and copper content is more susceptible to thermal cracking: False (these metals can act as catalyst poisons)
Fractional Distillation Products
The highest boiling point fraction from atmospheric distillation is the residue, which comes out as the bottom product with a boiling point above 400°C.
The fractions obtained in the highest proportions are gasoline (which can be further reformed), diesel, and kerosene.
The fractions obtained in the lowest proportions are solids and LPGs.
Petroleum Management in Spain
The transport, storage, and distribution of petroleum products in Spain are managed by CLH (Compañía Logística de Hidrocarburos).
Further Treatment of Heavy and Medium Oil Fractions
Heavy Fractions
- Crystallization: Used to produce waxes, lubricants, and greases.
- Refining: Can produce diesel, kerosene, and petrochemical feedstocks.
Medium Fractions
- Cracking: Breaks down larger molecules into smaller ones, often using catalytic cracking, to produce industrial fuels.
- Refining: Can produce various valuable products.
Purpose of Vacuum Distillation
Vacuum distillation is used to separate the heavier fractions of crude oil that cannot be distilled at atmospheric pressure without thermal decomposition.
Preliminary Operations Before Fractional Distillation
Before fractional distillation, crude oil undergoes several preliminary steps, including:
- Separation of dry gases (LPGs) from wet gas.
- Dehydration to remove saltwater.
- Desulfurization and removal of certain metals.
Units Used in the Oil Industry
Common units used in the oil industry include:
- Therm (most common)
- Ton of oil equivalent (toe)
- Gigajoule (GJ)
Natural Gas as a Clean Hydrocarbon
Compressed natural gas (CNG) can be considered a clean hydrocarbon fuel when it contains minimal impurities. It is used in transportation and domestic applications without requiring further transformation. While CO2 emissions from burning natural gas are still a concern, they are generally lower than those from other fossil fuels.
Advantages of Natural Gas’s Low Density
The low density of natural gas helps prevent the accumulation of solid particles, minimizing risks. Being lighter than air, it dissipates quickly into the atmosphere, reducing the impact of leaks.
Sources of Natural Gas
Natural gas can be found in association with oil deposits. It can also be produced through the anaerobic decomposition of organic waste, in which case it is called biogas.
Elements of a Natural Gas Transmission Plant
A natural gas transmission plant typically includes:
- Liquefaction plant
- Pipelines or transport vessels
- Regasification plant
Sweetening of Natural Gas
Sweetening is the process of removing acidic gases like carbon dioxide (CO2) and hydrogen sulfide (H2S) from natural gas. This process is necessary because these gases can cause corrosion and environmental problems.
Resurgence of Chemical Engineering in the 20th Century
Two key factors contributed to the resurgence of chemical engineering in the 20th century:
- Unification of theoretical principles applied to unit operations.
- Application of transport phenomena principles to the study of unit operations.
Locating a Chemical Plant for Vitamin B Syrup from Algae
This would likely be a batch process due to the seasonal availability of algae and the potential for small-scale production. Factors to consider for plant location include proximity to the coast (ideally in a sunny region like southern Galicia for drying), distance from potential sources of contamination (farms, septic tanks), access to clean water, industrial zoning, and transportation infrastructure.
Manufacturing Dog Food from Fish and Cereal Remains
Physical requirements include industrial land, licensing, transportation access, proximity to suppliers and customers, and distance from competitors. The process might involve steps like washing, grinding, mixing, extrusion, drying, cooling, pulverizing, packaging, and labeling. Economic considerations include grants and land costs.
Classification of Industries
- Caustic soda: Basic commodities
- Bleach: Intermediate pseudocommodities
- Aspirin: Consumer specialty
- Phosphate fertilizer: Final pseudocommodities
- Gelatin: Final, fine chemicals