Environmental Biotechnology: Water and Wastewater Lecture PDF

ENVIRONMENTAL BIOTECHNOLOGY LEC (BIOTECH302 LEC) 2nd Sem, SY 2024-2025 LECTURE 3. WATER AND WASTEWATER Compiled by: Prof. Mario B. Bigol Learning Outcomes: After completing this lecture, students will be able to understand, discuss and explain the following: 1. Hydrolo...

ENVIRONMENTAL BIOTECHNOLOGY LEC (BIOTECH302 LEC) 2nd Sem, SY 2024-2025 LECTURE 3. WATER AND WASTEWATER Compiled by: Prof. Mario B. Bigol Learning Outcomes: After completing this lecture, students will be able to understand, discuss and explain the following: 1. Hydrological Cycle 2. Wastewater 3. Physical Parameters 4. Chemical Parameters 5. Biological Characteristics 6. Disposal of Wastewater 7. Self-Purification of Natural Streams Intrduction As populations grow and natural environments become degraded, ensuring everyone has safe and sufficient water supplies is becoming increasingly challenging. A major part of the solution is to produce less pollution and improve the way we manage wastewater. Intrduction A more circular, sustainable economy means reducing contamination of ecosystems, and increasing the treatment, recycling and safe reuse of wastewater as a source of water, energy and nutrients. Water pollution is increasing throughout the water cycle. Due to population growth, accelerated urbanization and economic development, the quantity of wastewater being generated and its overall pollution load are increasing globally. Intrduction Industry and agriculture are often big water polluters. Increased usage of chemical fertilizers and pesticides, and untreated wastewater in irrigation, pollutes groundwater and surface water. Industry in many areas still discharges waste directly into water courses. Wastewater management is being seriously neglected. Across the world, safely reused wastewater is grossly undervalued as a potentially affordable and sustainable source of water, energy, nutrients and other recoverable materials. Intrduction Untreated wastewater in cities is a major issue. In poorer urban areas, a large proportion of wastewater is discharged untreated directly into the closest drainage channel or water body. Household effluent, human waste, toxic chemicals and medical waste are exposed to the air, contaminating the environment in often densely-populated residential zones. Water Water – one of the abundant compounds in nature - Covers approximately ¾ of the surface of earth. - Over 97% of the total quantity of water is in the oceans and other saline bodies of water. - Over 2% is tied up in polar ice caps and glaciers and in atmophere and as soil moisture. - 0.62% of water found in fresh, rivers and groundwater supplies irregularly and non-uniformly distributed over the vast of the globe. Hydrological Cycle Evaporation due to solar radiation. Water molecules convert into atmopheric vapor. Atmospheric water condenses and falls to the earth as rain and snow. Water flows into  Wastewater Wastewater is used water that has been affected by domestic, industrial and commercial use. 1 Wastewater is composed of 99.9% water and the remaining 0.1% is what is removed.1 0.1% contains organic matter, microorganisms and inorganic compounds.1 1 https://www.wwdmag.com/wastewater-treatment/article/10938418/what-is-wastewater Industrial Wastewater Effluent delivered out of a particular industry. Quality and quantity depends upon nature of industry, raw materials used, manufacturing process and housekeeping. Characteristics vary widely from idustry to industry. Physical Parameters Suspended solids – may consist of inorganic or organic particles. Turbidity – property of absorption of light or its scattering by suspended materials in water. Color - visible Taste and odor – caused by gases from the decomposition of organic matter. Temperature – rise in temperature enhances Chemical Parameters Total dissolved solds (TDS) – may be of organic or inorganic origin. Alkalinity – ability of water to neutralize acids. Hardness – due to dissolved divalent metallic cations like Ca++, Mg++. Fluoride – ingredients of igneous and sedimentary rocks. Inorganic salts – present in industrial wastes, Chemical Parameters pH – important parameter of both waters and wastewaters. Dissolved oxygen COD BOD Biological Characteristics Disposal of Wastewater Methods of disposal: 1. Natural methods – disposal by dilution. 2. Artificial methods – primary and secondary treatment. Self-Purification of Natural Streams When the wastewater or the effluent is discharged into a natural stream, the organic matter is converted into ammonia, nitrates, sulfates, acarbon dioxide, etc. by cateria. In this process of oxidation, the dissolved oxygen content of natural water is utilized. Due to this, deficiency of disslved oxygen is created. Self-Purification of Natural Streams As the excess organic matter is stabilized, the normal cycle will be in a process known as self-purification wherein the dissolved oxygen is replenished by its reaeration by atmospheric oxygen of wind. Resource Materials Webistes: 1. Srinivas, T. (2008). Environmental Biotechnology. New Age International (P) Ltd. pp. 93-104. Retrieved from: http://www2.hcmuaf.edu.vn/data/quoctuan/Environmental%20Biotechnology.pdf