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Water is vital for the entire aspects of life and also an important feature that defines our planet. Deprived water quality due to poor wastewater management is a crisis faced by every country in the world. This crisis affects directly and indirectly on our biological diversity, disturbing the entire ecosystem that act as our life support system (Corcoran et al, 2010). There are many factors affecting the aforementioned crisis and textile industry effluent is one of major contributor among other industrial wastewater (Verma, Dash, & Bhunia, 2012). Recent literature acknowledged dyeing and finishing processes is the main aforementioned contributor (Khandegar & Saroha, 2013). This paper combines a discussion of 1) textile industry process and their effluent, 2) conventional method of effluent treatment including their advantages and limitation and 3) the updated technology in treating textile industry effluent such as electrocoagulation, Bioflotation and Fixed Bed Biofilm Reactor.
Citation preview
• Textile industry effluent is one of the major contributor to
water pollution (Verma et al., 2012)
• Dyeing and finishing processes is the main aforementioned
contributor (Khandegar & Saroha, 2013).
• treating effluent from textile industry is a challenging task
due to the various type of pollutant content, inter alia;
organic and inorganic dye, heavy metal, surfactant, grease,
wax and suspended solid (Kurade et al., 2012)
• The discharging industrial effluent properly is lies on the
shoulder of industrial corporates.
• It is important to the specific industry to treat their effluent
onsite before discharge it into aqueous ecosystem.
Textile industry process (Batik processing)
Preparation of the cloth
Dyeing of the cloth
Application of the wax
Removing the wax
Source: JadiBatek.com.
POLUTION SOURCES
Process Compounds
Preparation of cloth Used oil (castor or coconut oil),
Starch
Dyeing of the cloth Organic and Inorganic dyes,
ludigol, potassium aluminum
sulfate, sodium alginate
Application of the wax Wax, dyes
Removing the wax Grease, surfactant, suspended
solids, colors
Source: JadiBatek.com.
Conventional technique
• Dye pollutions been a general focus in wastewater treatment since the colour change in water body easily detected even by bare eye (Vargas et al., 2011)
• There are a couple of common ways to discharge dyes have such as physical-chemical technique destroying the colour group, chemical oxidation and biological process mineralizing the colourless organic intermediate etc. (Khandegar and Saroha, 2013 and Kurade et al., 2012)
• Conventional techniques have limited ability to remove pollutant completely, non-practical, produces toxic sludge, sometimes required another disposal technique, and add to unnecessary cost projection.
Conventional method Advantages Disadvantages
Activated carbon Excellent removal for
wide variety of dyes
Decrease the
concentration of
dissolved organic solid
Very
expensive
Involves the
loss of
adsorbent
Biological treatment
Anaerobic process
Activated sludge
process
Oxidation ponding
Capable to degrade
certain type of dye
(non-toxic dyes)
Large area
requirement
Long
treatment time
Catalytic wet oxidation Capable to remove the
low concentration of
organic contaminant
Do not produce by-
product
Produce
carbon dioxide
Source : Khandegar and Saroha, (2013) and Kurade et al., (2012)
Conventional
method
Advantages Disadvantages
Chemical
oxidizing agent
Effective to
remove textile
industry effluent
Formation of
absorbable
organohalides (toxic
substance)
Coagulation Effective for
sulphur and
dispersive dyes
removal
Not effective for acid,
basic, direct, vat and
reactive dyes.
Produce large amount
of sludge
Increase Total
Suspended Solid
(TSS) content
Cucurbituril Good sorption
capacity for
various dyes
High cost
Conventional
method Advantages Disadvantages
Electrochemical
destruction
Breakdown non-
hazardous compound
High cost of
electricity
Fentons reagent Effective to decolour
soluble and insoluble
dyes.
Produce
sludge
Ion exchange Regeneration : no
adsorbent loss
Only effective
for specific
dyes
Irradiation Oxidation only
effective at lab scale
A lot of
dissolved
oxygen
required
Source : Khandegar and Saroha, (2013) and Kurade et al., (2012)
Conventional
method Advantages Disadvantages
Membrane
filtration
Capable to remove all
types of dyes
Less space requirement
Do not produce sludge
Minimize the used of
fresh water during
treatment (recycle and
reuse)
High cost
NaOCl Accelerates and initiates
azo-bond cleavage
Release
aromatic
amine
Source : Khandegar and Saroha, (2013) and Kurade et al., (2012)
Conventional
method Advantages Disadvantages
Ozonation Applied in
gaseous state: no
volume change
Short half-life (20
min)
Hazardous
substances (
require ozone
destruction unit)
Peat Good adsorbent
due to cellular
structure
Lower specific
surface area for
adsorption are
compared to
activated carbon
Photochemical Do not generate
sludge
Produce by-
product
Conventional
method Advantages Disadvantages
Silica gel Only effective to
remove basic dye
Side reaction
prevent
commercial
application
Wet air
oxidation
Effective for
removal high
organic matter or
toxic contaminants
content
High installation
and operating cost
Wood chips only effective to
remove acid dyes
Long retention
times requirement
Source : Khandegar and Saroha, (2013) and Kurade et al., (2012)
ADVANCE TECHNOLOGY (Electrocoagulation + other method)
• electrocoagulation remove 97% of colour from water
body while coagulation (Alum) method remove 94 % of
dye content in the textile effluent.
• combination of electrocoagulation (EC) technique with
other method shows high effectiveness for removing
BOD, COD, color and turbidity from textile industry
wastewater (Khandegar and Saroha, 2013).
Combination technology Results (%)
EC + Electroflotation BOD (88.9), Color (93), COD
(79.7 ), Turbidity (76.2), SS
(85.5)
EC + Sedimentation COD (70), Turbidity (90)
EC + Nanofiltration Color(>99)
1)Bioflotation, 2)FBBR, 3)flow jet and 4)a standard activated sludge system. (Souce : Papadia et al., 2011)
ADVANCE TECHNOLOGY (Fixed Bed Biomass Reactor)
• FBBR is an effective advance technology used in treating
textile industry wastewater due to their high capability
holding high loads of very active biomass over time and
for their ability to handle high and variable organic loads.
• The segregated zones in FBBR system enhance the
sludge mineralization by decrease the washout of
biomass (Papadia et al., 2011)
ADVANCE TECHNOLOGY (Bioflotation Reactor)
• Bioflotation is an effective advance technology used in treating in treating dyeing and finishing effluent form textile industry.
• Bioflotation technologies are less affected by organic loads (the organic load rate up to 0.40 kgCOD /m3/day)
• The high pressure ejector air supply system in bioreactor provides largest air wastewater contact surface, thus produce high oxygen dissolution (Papadia et al., 2011).
CONCLUSION
• The findings of recent study related to textile industry
wastewater management is still not clear to determine the
most appropriate technique and technology to be used.
• More studies should be conducted and latest technologies
should be developed to answer to the earth’s urgency in
managing wastewater cycles effectively, for marine lives to
be saved and global water streams to be preserved.
CITED REFERENCES Corcoran, E., Nellemann, C., Baker, E., Bos, R., Osborn, D., Savelli, H. Sick Water? The central role of
wastewater management in sustainable development. A rapid response assessment, United Nations
Environment Programme. UN-HABITAT, GRID; Arendal: 2010.
Khandegar, V., & Saroha, Anil K. (2013). Electrocoagulation for the treatment of textile industry effluent –
A review. Journal of Environmental Management, 128(0), 949-963. doi:
http://dx.doi.org/10.1016/j.jenvman.2013.06.043
Kurade, Mayur B., Waghmode, Tatoba R., Kagalkar, Anuradha N., & Govindwar, Sanjay P. (2012).
Decolorization of textile industry effluent containing disperse dye Scarlet RR by a newly developed
bacterial-yeast consortium BL-GG. Chemical Engineering Journal, 184(0), 33-41. doi:
http://dx.doi.org/10.1016/j.cej.2011.12.058
Papadia, Simone, Rovero, Giorgio, Fava, Fabio, & Di Gioia, Diana. (2011). Comparison of different pilot
scale bioreactors for the treatment of a real wastewater from the textile industry. International
Biodeterioration & Biodegradation, 65(3), 396-403. doi: http://dx.doi.org/10.1016/j.ibiod.2011.01.002
Steiner, A. and Tibaijuka, A.K., (2010). Join statement. In Corcoran, E., Nellemann, C., Baker, E., Bos, R.,
Osborn, D.,Savelli, H. Sick Water? The central role of wastewater management in sustainable development.
A rapid response assessment, United Nations Environment Programme. UN-HABITAT, GRID; Arendal:
2010.
Verma, Akshaya Kumar, Dash, Rajesh Roshan, & Bhunia, Puspendu. (2012). A review on chemical
coagulation/flocculation technologies for removal of colour from textile wastewaters. Journal of
Environmental Management, 93(1), 154-168. doi: http://dx.doi.org/10.1016/j.jenvman.2011.09.012