Best Value Chem Computer Operator Interview Questions and Answers

Concrete is a strong and durable building material made from a mixture of cement, sand, gravel, and water.

• Concrete is commonly used in construction for buildings, roads, bridges, and more

• It is known for its strength, durability, and versatility

• The ingredients of concrete include cement, sand, gravel, and water

• Concrete can be poured into molds to create various shapes and structures

Admixtures are added to concrete to alter its properties or enhance its performance. They can improve workability, durability, and strength.

• Admixtures are added to concrete during mixing to modify its properties.

• Types of admixtures include water-reducing, air-entraining, accelerating, retarding, and plasticizers.

• Water-reducing admixtures improve workability and reduce water content.

• Air-entraining admixtures create smal...read more

Construction materials have various properties that affect their performance and durability.

• Strength: Ability to withstand loads without breaking or deforming (e.g. concrete, steel)

• Durability: Resistance to wear, weathering, and deterioration over time (e.g. brick, stone)

• Density: Mass per unit volume, affects weight and insulation properties (e.g. wood, foam)

• Thermal conductivity: Ability to conduct heat, important for ...read more

Mix design for different grade involves determining the proportions of materials to achieve desired concrete properties.

• Identify the required grade of concrete based on project specifications.

• Select suitable materials such as cement, aggregates, and water.

• Calculate the mix proportions based on desired strength and workability.

• Perform trial mixes and adjust proportions as needed.

• Test the concrete for desired properties ...read more

The optimum diameter of a pump depends on various factors such as flow rate, head, viscosity, and efficiency.

• The diameter should be selected based on the required flow rate and head of the system.

• Higher viscosity fluids require larger diameter pumps to reduce frictional losses.

• Efficiency of the pump increases with larger diameter impellers.

• The diameter should also be selected based on the available space and cost const...read more

Stream balance inside distillation column is crucial for efficient separation of components.

• Stream balance refers to the equal distribution of feed and product streams across the column.

• Imbalance can lead to poor separation efficiency, flooding, or tray damage.

• Factors affecting stream balance include tray design, liquid and vapor flow rates, and column diameter.

• Techniques such as tray hydraulics and computational fluid...read more

Designing a distillation column for binary mixtures involves determining the number of trays, feed location, and reflux ratio.

• Determine the boiling points of the components

• Calculate the minimum reflux ratio

• Choose the number of trays based on the desired separation

• Determine the feed location based on the composition of the feed

• Design the reboiler and condenser

• Consider the pressure drop across the column