Sustainability and Environmental Engineering
Sustainability and Environmental Engineering
Sustainability is defined by Merriam-Webster as follows: (1) of, relating to, or being a method of harvesting or using a resource so that the resource is not depleted or permanently damaged and (2) of or relating to a lifestyle involving the use of sustainable methods.
Sustainable development is defined as “development which meets the needs of the present without compromising the ability of the future to meet its needs.”
Sustainable engineering is the design of human and industrial systems to ensure that humankind’s use of natural resources and cycles do not lead to diminished quality of life due either to losses in future economic opportunities or to adverse impacts on social conditions, human health, and the environment.
The 3 Basic Pillars of Sustainability
- People: Fair practices for all people and does not exploit interest of separate parties based on money, status or growth.
- Planet: Management of renewable and non-renewable resources while reducing waste.
- Profit: Financial benefit enjoyed by the majority of society.
Life Cycle Assessment (LCA) is a technique used to quantify the environmental impact of a product from raw material acquisition through end-of-life disposition.
Water Treatment and Management
Water treatment transforms raw surface and groundwater into safe drinking water. Water treatment involves two types of processes: physical removal of solids and chemical disinfection.
Drinking Water Treatment Plant (DWTP)
Water resource → Water abstraction → Raw water storage → Pre-treatment → Coagulation and Flocculation, Sedimentation, Filtration → Chlorination → Storage → Distribution.
Desalination is the process of removing dissolved salts and minerals from seawater or brackish water. Desalination produces drinking water and concentrate.
Advantages of Desalination
- Unlimited resources due to its abundance
- Constant salinity
- Known physical and chemical characteristics
Disadvantages of Desalination
- High salinity
- Corrosive
- Frequent and abundant biological fouling
- Restricted use (coastal areas)
- High cost of desalination
Wastewater Treatment
The main objective of wastewater treatments is to remove or reduce the concentration of different chemical substances found in waters due to their use, which can be hazardous for the environment and health.
Wastewater Treatment: Pre-treatment → Preliminary treatment (Removal of Organic Matter) → Primary treatment (Removal of Suspended Solids) → Secondary treatment (Removal of Organic Matter) → Tertiary treatment (Removal of Pathogens and Nutrients) → Sludge (biosolids) disposal → Water disposal / Water use.
Atmospheric Pollution and its Effects
Atmospheric pollution refers to the disturbance adding gases, solids, or liquids particles, in rates different to the natural ones. This term is usually applied when these changes are able to damage health or the environment.
Air Pollutants: Ozone (O3), (PM), (NOx), (SO2), (CO), (CO2).
Effect of Pollutants: Ozone depletion, Acid Rain, Greenhouse effect, Thermal.
Acid rain is rain or any other form of precipitation that is unusually acidic, meaning that it possesses elevated levels of hydrogen ions.
The greenhouse effect is a process by which thermal radiation from a planetary surface is absorbed by atmospheric GHG and is re-radiated in all directions. Since part of this re-radiation is back towards the surface and the lower atmosphere, it results in an elevation of the average surface temperature above what it would be in the absence of the gases.
Environmental Impact Assessment
Environmental impact assessment is the formal process used to predict the environmental consequences (positive or negative) of a plan, policy, program, or project prior to the decision to move forward with the proposed action.
Steps of Environmental Impact Assessment
- Analysis of the project and its actions
- Analysis of alternatives
- Identification of actions capable of producing impacts
- Identification of factors in the environment susceptible to suffer impacts
Environmental Impact: Any change happened in the environment, being positive or negative, totally or partially coming from activities, products or services of an organization.