Water Treatment Flashcards
4 step Water filtration of raw water in pipe
Microfiltration>ultrafiltration>nanofiltration>reverse osmosis
What is membranes base desalination process?
a process
that uses membranes to remove salt and
other impurities from seawater or
brackish water
Most common membrane-based
desalination technology (ada 1)
Reverse
Osmosis (RO), which uses pressure to
force water through a semi-permeable
membrane to remove salt and other
impurities
What method that offer high
efficiency and lower energy consumption
than distillation methods?
membrane-based technologies
include Microfiltration (MF), Ultrafiltration
(UF), and Nanofiltration (NF)
What Organic-hybrid and inorganic membrane
materials offer ada (4) ?
offer advantages, with high
flux, good selectivity, and useful chemical
and thermal resistance
Simple knowledge about Membrane distillation process?
- low temperature thermal
evaporative process that offers several advantages over
traditional desalting methods.
The principle of separation in MD
based on the difference in
volatility with vapor pressure being the driving force
How membrane distillation work ?
-hydrophobic porous membrane is employed as a barrier
separating heated feed and cold permeate streams.
As a heated aqueous solution passes through its lumen, it is partially transformed to water vapor.
-The hydrophobicity prevents the aqueous solution from
entering the pores.
-In this article, we demonstrate the
immobilization of graphene oxide (GO) on
polytetrafluoroethylene (PTFE ) membrane surface for
desalination via direct contact membrane distillation.
4 Steps of RO drinking water system
Step 1: Pre-Filtration
-The system connects to drinking water
lines and uses a high-pressure pump to
propel feed water through.
-Feed water passes through a series of
filters, usually carbon-based, designed to
catch sediment and mineral deposits
before flowing into the RO chamber.
Step 2: Reverse Osmosis
Here, the feed water is pushed through the
semipermeable membrane.To give you an idea of how stringent
the membrane is, the diameter of a
strand of human hair is roughly 100
microns wide. But, in Culligan RO
Systems, the spaces in the
membrane are approximately ONE
micron wide
Step 3 + 4: Drainage & Storage
-The system drains out all
contaminants not caught in filters at
each stage, and treated water is
stored in a small tank until used.
Membrane technology
- process used
in wastewater treatment to separate
contaminants from water based on
properties such as size or charge. - has emerged as a
favorite choice for reclaiming water
from different wastewater streams for
re-use. - used for removing
solids in wastewater treatment is usually based on ultrafiltration or
microfiltration. - can be introduced into
the biological wastewater treatment
process either as a separate unit
operation downstream of the biological
step, or integrated into the biological
process itself.
Membrane fouling
a common problem
in membrane technology - decrease in
the efficiency of the process. Membrane
cleaning is necessary to maintain the
performance of the membrane
Membrane Bioreactor (MBR)
MBR wastewater treatment is a process
that combines a biological process,
such as activated sludge, with a
membrane process, such as
microfiltration or ultrafiltration, to treat
wastewater.
qThe activated sludge process is a type
of biological wastewater treatment
process for treating sewage or
industrial wastewaters using aeration
and a biological floc composed of
bacteria and protozoa. It uses air (or
oxygen) and microorganisms to
biologically oxidize organic pollutants,
producing a waste sludge (or floc)
containing the oxidized material.
MBR wastewater treatment
has a smaller footprint,
produces high-quality
effluent, and removes organic
and nitrogen compounds
from the wastewater.
a different process that
uses plastic carriers with
biofilm to decompose waste
and achieve nitrification and
denitrification
Membrane Bed Bioreactor
(MBBR)
stands for Moving Bed Biofilm Reactor, takes place in an aeration tank with
plastic carriers that a biofilm can grow on ,compact size and cheap wastewater
treatment costs offers many advantages for the
system.
qThe main objective of using MBBR being water
reuse and nutrient removal or recovery.
• The MBBR system consists of an aeration tank
with special plastic carriers that provide a
surface where a biofilm can grow.
• Wide variety of plastic carriers - vary in surface
area and in shape, each offering different
advantages and disadvantages.
• Surface area plays a very important role in
biofilm formation.
MBR vs MBBR
1.MBR combines biological treatment with
membrane filtration, while MBBR utilizes
biofilm growth on plastic media carriers.
2.MBR relies on membranes to separate treated
water from solids, while MBBR relies on a
biofilm attached to media carriers to treat
wastewater.
3.MBR can effectively improve sludge load,
while MBBR belongs to biofilm process, both
of which have good effect on organic
pollutant treatment, including COD, BOD and
ammonia nitrogen.
4.MBR has obvious effects in treating SS, but it
is a problem that it is easy to block the
membrane.
Dialysis Membrane
when it start, high concentration .
When it end, equilibrium
