JNTU B.Tech IV HEALTH, SAFETY AND ENVIRONMENT IN PETROLEUM INDUSTRY Previous Question Paper (September - 2020 - R16)

Petroleum industry wastes, including produced water, drilling muds, oily sludges, and refinery effluents, are treated using a combination of physical, chemical, and biological processes to ensure environmental compliance.

Physical Treatment: These methods rely on density differences and mechanical separation. Gravity separation (e.g., API separators) allows free oil to float and solids to settle. Dissolved Air Flotation (DAF) uses micro-bubbles to attach to oil droplets, increasing their buoyancy for skimming. Filtration using sand or membrane media removes suspended solids and fine oil emulsions.

Chemical Treatment: This involves altering the chemical state of pollutants to facilitate removal. Coagulation and Flocculation use chemicals like alum or polymers to neutralize charges on colloidal particles, causing them to aggregate into larger flocs that can be settled or filtered. Chemical Oxidation (e.g., using ozone or hydrogen peroxide) breaks down complex organic contaminants and toxic hydrocarbons into simpler, less harmful substances.

Biological Treatment: This utilizes microorganisms to degrade organic matter. Aerobic processes, such as Activated Sludge or Bio-filters, use oxygen to convert dissolved hydrocarbons into carbon dioxide and water. Anaerobic processes are effective for high-strength organic wastes, converting them into methane and biomass in the absence of oxygen. Landfarming is a common method for oily sludge, where waste is spread over soil and degraded by indigenous soil microbes through tilling and nutrient addition.

Thermal Treatment: Incineration involves high-temperature combustion to destroy hazardous organic compounds, while Thermal Desorption uses heat to vaporize hydrocarbons from contaminated soil or sludge, allowing them to be captured and treated separately.

Biological effects of nuclear radiation are primarily classified into two categories: somatic effects and genetic effects. These classifications are based on whether the damage manifests in the exposed individual or their future offspring.

1. Somatic Effects
Somatic effects occur in the body cells of the individual exposed to radiation. These effects can be further subdivided into two types:

• Acute (Deterministic) Effects: These occur shortly after exposure to high doses of radiation. The severity of the effect is proportional to the dose received. Examples include radiation sickness, skin burns, hair loss, and in extreme cases, death due to organ failure.
• Delayed (Stochastic) Effects: These occur years after exposure, often from lower doses. The probability of occurrence, rather than the severity, increases with the dose. The most significant delayed effect is the development of cancer, such as leukemia or solid tumors.

2. Genetic Effects
Genetic effects occur when radiation damages the DNA within the reproductive cells (sperm or ova) of the exposed individual. Unlike somatic effects, these do not manifest in the exposed person but are passed on to their descendants. These mutations can lead to hereditary disorders, congenital malformations, or developmental abnormalities in future generations. Because these effects are stochastic, even low levels of radiation exposure are considered to carry a potential risk of inducing genetic damage, necessitating strict adherence to safety protocols in industrial and medical environments.