(a) ENERGY
CONSERVATION IN SIZING
Foam sizing : in this method foam
is used for sizing. Hence considerably less water is required as compared to
the conventional sizing. This results is saving in energy and time for
evaporation of size.
High pressure squeezing during
sizing : this saves the energy as well as the water. after sizing material is
squeezed at high pressure to remove maximum water from it. Because of this
energy required for drying the material is saved.
Simultaneous dyeing and sizing:
for denim warp yarns by using rapiodogen dyes and stabilizer with sizing
formulation sizing and dyeing can be carried out simultaneously. This saves
energy and water.
B) ENERGY CONSERVATION IN
BLEACHING
Fast bleaching with VAPORLOC
machine
Mather and platt developed this
machine. In this machine, bleaching can be carried out in 90 to 120 seconds at
a temperature of 135 degree C. and pressure 30-psi. for this process hydrogen
peroxide, stabilizers and suitable alkali is used. 50% energy can be saved with
this process.
Novel method : this is a combined
desizing scouring and bleaching of polyster/cotton blend. This is carried out
is which using material to liquors ratio1:25. the liquor consists of hydrogen
peroxide(35%w/v) magnesium sulphate heptahydrate (1.6gpl) sodium
hydroxide(4gpl) wetting agent (0.5gpl) EDTA(2gpl) and gluconic acide (2gpl) at
95 degree C for one hour. The washing is giving at 95 degree C.
Potassium permanganate method :
cotton goods can be bleached with potassium permanganate. This saves energy and
water. It also gives eco-friendly effluent.
Cold pad-batch method : in this
method peroxide bisulfate used as a bleaching agent. The bath also contains
some compounds which accelerate the bleaching reaction like urea glucose sodium
citrate methyl carbonate tetra acetyl ethylene diamine etc.
DSB process: in this process
desizing scouring and bleaching takes place in a single stage. The bath
contains hydrogen peroxide peroxygen booster sodium silicate peroxide sulphates
etc. to this some compounds like urea glucose which accelerate the peroxide
reaction are added. This process saves energy water and labor.
C) ENERGY CONSERVATION IN
MERCERISATION
It is the process in which the
material is treated with concentrated sodium hydroxide solution indeally at at
15 to 20 degree C. this gives luster to the material and the absorptivity of
the material is increased considerably.
In mercerization process saving in
energy can be done if the process is carried out on wet-on-wet basis I e the in
between drying process is eliminated which saves the energy.
Hot mercerization can be done so
that scouring is eliminated at 70*c so without doing separate scouring process
yarn or fabric is directly subjected to hot mercerization.
Caustic recovery : for the caustic
recovery maximum washing is given to the fabric. Temperature of the washing
water is maintained at 90*c and suction is provided. All this results in 80 to
85% of the caustic recovery.
D) ENERGY CONSERVATION IN DYEING
Cost savings and quality
improvement in dye house can be dine by some process modifications and suitable
replacement of processing machines.
Some of these processes are given
bellow.
Energy saving by padding mangle
Cost savings and quality improvement
in dye house can be done by some process modifications and suitable replacement
of processing machines.
Some of these processes are given
bellow.
Energy saving by padding mangle
Padding mangle mainly used for two
purposes 1) to impregnate any processing solution in fabric 2) to remove excess
amount of processing liquor from the fabric by squeezing. Kusters mangle is a
modified from which has uniform expression percentage with low wet pick-up.
Expression percentage can be changed by changing speed and pressure. On this
machine uniform and accurate results are obtained with the saving in energy.
Pad-jig method
This method can be used for dyeing
with vat reactive azoic dyes with this method. Dyeing quality is improved with
respect to levelness and solidity of shades. Dye penetration is also good. In
this power & steam required is less.
