LO1

Question 1

Hydro-cyclone:

Answer 1

Function: It utilizes centrifugal force to separate solid particles from the wastewater. The incoming wastewater is introduced into the cyclone, creating a vortex that causes heavier particles to move towards the wall and be collected as underflow, while lighter particles are carried to the center and discharged as overflow.

Question 2

Coalesce:

Answer 2

Main Component: Coalescers typically consist of a series of closely spaced plates or fibers.

Function: Coalescers facilitate the merging of small oil droplets suspended in the wastewater into larger ones. As the wastewater passes through the coalescer, the oil droplets come into contact with the coalescing media and coalesce into larger droplets, making them easier to separate from the water phase.

Question 3

Flotation Treatment:

Answer 3

Main Component: Flotation tanks or units equipped with mechanisms to introduce air bubbles into the wastewater.

Function: In flotation treatment, air bubbles are introduced into the wastewater, attaching to the oil droplets and causing them to float to the surface, forming a froth layer (skimmings). The froth layer is then mechanically removed, separating the oil from the water.

Question 4

Produced Water Disposal

Answer 4

Discharge into the sea
Re-injection
Treatment

Question 5

Discharge into the sea

Answer 5

Produced water, a byproduct of oil and gas extraction, is treated to remove contaminants including oil, solids, and chemicals. After treatment, the water is discharged into the sea in compliance with environmental regulations, ensuring minimal impact on marine ecosystems.

Question 6

Re-injection

Answer 6

In this method, treated produced water is reinjected into suitable geological formations deep underground, often into depleted oil reservoirs. This practice helps maintain reservoir pressure for enhanced oil recovery while safely disposing of produced water.

Question 7

Treatment

Answer 7

Produced water undergoes treatment to remove contaminants, including hydrocarbons, suspended solids, dissolved solids, and chemicals. Treatment processes may include gravity separation, filtration, chemical flocculation, and biological degradation, ensuring compliance with environmental regulations before disposal or re-injection.

Question 8

Sewage treatment

Answer 8

Physical separation: separation of insoluble particles and solids using gravityseparation, gas flotation, or hydrocyclones
Chemical treatment: added to the water for pH adjustment, flocculation andcoagulation. Chemicals may also be added to aid precipitation.
Biological treatment: disposal of waste water by aeration (open type or closedtype) is used to remove organic materials from the water.

Question 9

Open air type aeration method

Answer 9

Activated sludge from the sedimentation tank and the wastewater aremixed with the air in an open-air aeration tank

Question 10

Close type aeration method

Answer 10

Activated sludge from the sedimentation tank and the wastewater aremixed with oxygen in closed aeration tank.