Wastewater Treatment: Primary and Secondary Processes
Primary Wastewater Treatment
Primary separation of finer suspended solids not separated in pretreatment.
1. pH Control
A preliminary step before precipitation, coagulation-flocculation, biological processes, or the final stage before discharge. The basic principle is: acid + base = salt + water. Different neutralization processes are used for wastewater:
- a) Acidic wastewater: Strong bases (CaO, MgO, NaOH) are added in a stirred tank.
- b) Basic wastewater: Mineral acids are added in a stirred tank.
- c)
Big Bang Theory and Plate Tectonics: Key Concepts
The Big Bang Theory
The Big Bang Theory was proposed by the Belgian astronomer Georges Lemaître in 1927 and developed by Russian-born American physicist Georges Gamow in 1948. It posits that the universe was created from a singular event, the Big Bang, as follows:
- Initially, all energy, matter, and space were concentrated in a single point, called the primeval atom, characterized by extremely high density and temperature.
- This primeval atom expanded rapidly in a Big Bang, initiating the expansion
Natural Hazards, Resources, and Sustainable Development
Water Cycle: (Rainfall, infiltration, evaporation) solar-driven. Oceanic Conveyor Belt: Distributes heat to all the seas of the planet.
Natural Hazards
Floods: A natural phenomenon with the most casualties. Overflowing rivers or streams, especially in the Mediterranean area (wadi, intermittent water courses), cause strong slope erosion.
Landslides: Falling materials due to steep slopes, often caused by heavy rains and earthquakes. Rock type is a significant risk factor.
Earthquakes: Ground vibrations
Read MoreMezquita-Cathedral of Córdoba: History & Architecture
Mezquita-Cathedral of Córdoba: Construction Phases
At the top, we have three arches, and between them, there are plaques carved with plant motifs. An overhang topped by battlements and supported on toothed roll corbels. The side streets are identical. A vain and blind to the lintel, lintels voussoired, just above the extrados is staggered through the provision of recessed blocks. Decorated with vegetal elements in size to bevel as palms, volutes (plasterwork) deeply rooted in the Visigoth world.
Read MoreUnderstanding Atmospheric Circulation and Climates
Key Meteorological Concepts
- Latitude: The distance between the Equator and a point on the planet, measured along the meridian passing through that point.
- Gale: The clash of air masses from the poles with air masses from the tropics.
- Anticyclone: An area under atmospheric pressure above normal pressure (1016 mb). Anticyclones usually produce stable weather without precipitation.
- Precipitation: Water that falls on Earth’s surface from clouds, in liquid or solid form. It is measured with a rain gauge
Wind, Coastal, Glacial, and Karst Landform Modeling
Wind Modeling
Wind Action: Wind is the primary agent shaping landscapes in hot deserts. In these areas, wind carries out two main erosion processes:
- Deflation: Wind carries away smaller materials, leaving behind larger ones, resulting in a rocky desert known as a reg.
- Abrasion: Wind laden with sand polishes rock surfaces.
Wind Transport and Sedimentation: Wind carries large volumes of fine materials over enormous distances. Fine sand and dust are carried high into the troposphere, where they can remain
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