Process of Environmental Impact Assessment - Stages in EIA

The first step of EIA process to decide whether or not EIA is required. It is a preliminarily study to investigate the negative and positive impacts of a proposed project. The project type and size is used to evaluate the extent of potential environmental impacts. Small projects some time have more adverse environmental effects than larger projects . Therefore, the

Types of Activated Sludge Process - Plug Flow, Complete Mix, SBR

In CMAS, mixing of tank contents is sufficient so that ideally concentrations of mixed-liquor constituents, soluble substances (COD, BOD, NH4-N), and colloidal and suspended solids do not vary with location in aeration basin. Plug Flow involves relatively long and narrow aeration basins so that concentration of soluble substances and colloidal and suspended solids

Biological Nitrification Process in Waste Water Treatment System

Total concentration of organic and ammonia nitrogen in municipal wastewater in the range 25‐ 45 mg/L as nitrogen based on flowrate of 450 L/capita.d (120 gal/capita.d). With limited water supplies, total nitrogen in excess of 200 mg/L as N measured in domestic wastewater. Drinking water maximum MCL for nitrate nitrogen is 45 mg/L as nitrate or 10

Manufacturing and Uses of Portland Cement

Cement can be defined as the bonding material having cohesive & adhesive properties which makes it capable to unite the different construction materials and form the compacted assembly. Ordinary/Normal Portland cement is one of the most widely used type of Portland Cement. The name Portland cement was given by Joseph Aspdin in 1824 due to its similarity in

Process of Steel Manufacturing

The first step in the steel manufacture begins at the blast furnace. To separate iron from iron ore ► coke (substance when gas is taken out of coal), limestone and dolomite are charged into the blast furnace. Temperature raised to 1600oF. This high temp causes the coke to burn and melt the iron. This red hot iron drained at an opening at the base of the furnace. Natural

Factors Affecting Precipitation Formation

Following are the factors mainly responsible for the formation of precipitation....A lifting mechanism to produce cooling of the air. A mechanism to produce condensation of water vapors and formation of cloud droplets. A mechanism to produce growth of cloud droplets to size capable of falling to the ground against the lifting force of air. When air ascends from near the

The Geological Cycle of Rock formation

Geological cycle includes many processes acting simultaneously. The most important of these begin with molten magma from within the earth forming into rock, then continue with rocks being broken down into soil, and that soil being converted back into rock.

Uses & Design of Flow Equalization Tank

Flow equalization is method used to overcome the operational problems and flow rate variations to improve the performance of downstream processes and to reduce the size & cost of downstream treatment facilities. To prevent flow rate, temperature, and contaminant concentrations from varying widely, flow equalization is often used. Variations occur

Distributary Head Regulator - Definition, Working Mechanism

The distributary head regulator is constructed at the upstream end (i.e., the head) of a channel where it takes off from the main canal or a branch canal or a major dis-tributary. The distributary head regulator should

Methods & Techniques of Irrigation

The pressurized systems include sprinkler, trickle, and the array of similar systems in which water is conveyed to and distributed over the farmland through pressurized pipe networks. There are many individual system configurations identified by unique features (centre-pivot sprinkler systems). 2. Gravity Flow Irrigation Systems convey and distribute water at the field

Municipal Wastewater Treatment Systems

Collection of domestic wastewater is best achieved by a full sewerage water drain age system. Unfortunately this method is most expensive and there is relatively few communities in hot climate which afford it. A modern hygienic method of night soil collection is the only realistic alternative. Treatment is required principally to destroy pathogenic agents in sewage or night

Secondary Biological Wastewater Treatment Process

The main objective of secondary treatment: To remove most of the fine suspended and dissolved degradable organic matter that remains after primary treatment, so that the effluent may be rendered suitable for discharge. Conventional secondary treatment can reduce the BOD's

Activated Sludge Wastewater Treatment Process

Is defined as a ‘Suspension’ of microorganisms, both living and dead’ in a wastewater. The microorganisms are active by an input of air (oxygen) thus known as activated-sludge. Activate-sludge is that sludge which settle down in a secondary sedimentation tank after the sewage has been freely aerated and agitated for a certain time in an Aeration tank. It contains

Activated Sludge Process Design

The activated sludge form the underflow of the final setting tanks should be returned to the inlet of the aeration tanks at a rote sufficient to maintain the MLSS concentration at the design value. Excess activated sludge withdrawal system and subsequent treatment and disposal of waste sludge. Since the whole process takes place in a liquid medium the hydraulic

Engineering Hydrology Class Lectures and Notes

Engineering Hydrology Helps in the following ways: Hydrology is used to find out maximum probable flood at proposed sites e.g.. Dams. The variation of water production from catchments can be calculated and described by hydrology.