Aeration

for values ? removal may not be feasible

10 to 100

a volatility of a substance with a factor over ? can easily be removed l.

100

normal air to water ratio at a peak flow in a packed tower aerator

25:1

the minimum air to water ratio at peak flow in a packed tower

25:1

small towers designed to remove relatively volatile compounds may require

5hp

the maximum should be no more than ? in an air to water ratio

80:1

consists of an aeration basin or tank constructed of steal or concrete, equiped with air piping, manifolds, and diffusers.

Diffuser aerators

the relative votality of a substance is expressed as ?

Henry's constant

the process of bringing water and air into close contact to remove or modify consitituents in water

aeration

used to transfer volatile contaminants into the air

aeration

two main aeration methods

air into water and water into air

removal of organic compounds, odorous substances, carbon dioxide and radon

air stripping or desorption

how can the packing be cleaned ?

backwashing

can be used to oxidize iron and partially reduced dissolved gases occuring in splash areas

cascade aerator

type of aerator occurs in splash areas and can be used to oxidize iron and partially reduced dissolved gases

cascade aerator

5 components to a ring tyoe cascade aerator

central feed pipe, overflow baffle, spray bottle, outlet, inlet, aluminum

two types of blowers

centrifugal and positive displacement

air flow is provided by a

centrifugal blower driven by an electric motor

used to oxidize iron, although their primary use is to reduce dissolved gasses and are similar to ring type cascade aerators

cone aerator

removes moisture from the air as it leaves to prevent objectional clouds of moisture coming from the column

demister

in general, spray aeration is sucessful in oxidizing iron or manganese and is very sucessful in increasing what characteristic of water ?

diffused oxygen level

type of aeration used primarily to uncrease the DO content in order to prevent taste and odors ?

diffuser aerator

when injecting oxygen into the water it will increase

dissolved oxygen

much more efficient for dissolved gas removal and for oxidizing iron and manganese

draft aerator

type of aerator is much more efficient in removing dissolved gases and for oxidizing iron and manganese

draft aerator

uses an air flow created by a blower

draft aerator

uses a submersible pump equipped with a draft tube (air intake pipe), creates a vacuum at the spinning impellar causes air to enter through the water intake

draft tube aerator

are used to ensure better mixing when aerators are installed in deep aeration bsain

draft tube aerators two

the packing material in a packed tower is reffered to as ?

dumped packing

top mounted blower which pulls an upward flow of air from vents located near the bottom of the tower

induced draft aerator

type of aerator consisting of a propellar like mixing blade mounted on the end of a vertical shaft driven by a motor

mechanical aerator

increasing dissolved oxygen is great way to ? and remove ?

oxidize and remove contaminants

a cylindrical tank containing packing material with water distributed at the top and airflow introduced from the bottom by a blower, commonly reffered to as an air stripper

packed towers

commonly called air strippers, designed for removal of volatile organic chemicals from contaminated waters

packed towers

if their are any questions of how well a contaminant can be removed, what kind of test can be done ?

pilot plant test

type of packing normally used in water treatment for air strippers

plastic

composed of a tower of tiered slats and an external blower that provides continous flow of air

positive draft aerator

two types of draft aerator

positve draft type and induced draft type

aerator in an enclosed tank, primarily used to oxidize iron and manganese for later removal by filtration

pressure aerators

car must be taken in the blower intake to

prevent contaminants from entering

type of aerator commonly used to oxidize iron to a limit extent and to lower the concentration of dissolved gases. Consisting of three to 5 stack trays.

slack and coke tray aerators

a submerged air diffuser is called

sparger

in the slate and coke tray aerator is usually constructed to have sloping sides called ?, which are used to protect the splash from wind loss and freezing

splash aprons

consists of one or more nozzles connected to a pipe manifold. moving on a mainifold under pressure creating a fountain effect.

spray aerator

sometimes located in a decorative setting at the entrance to the water treatment plant

spray aerator

also used for aeration because the structure protects the spray from windblown losses and reduces freezing problems

spray tower (not packed towers)

aerators draw water into the blade of the aerator and throw the water into the air in tiny droplets, so that the water can pick up oxygen

surface aerator

4 types of mechanical aerators

surface, submerged, combination mechanical, and draft tube aerators