|Title of Invention||
PROCESS FOR OBTAINING CLEAN WATER FROM THE EFFLUENTS OF TEXTILE PROCESSING INDUSTRIES
|Abstract||There is provided a process for obtaining reusable clear water from effluents of textile processing industries, which comprises subjecting the effluent water to a double treatment, (i) a pH treatment using an alkali, preferably sodium hydroxide and (ii) a coagulation/precipitation treatment using preferably ferrous sulphate in any order or as a mixture followed by (iii) filtering the clean water through a bed of activated carbon.|
|Full Text||THE PATENT ACT, 1970
"PROCESS FOR OBTAINING CLEAN WATER FROM THE EFFLUENTS OF TEXTILE PROCESSING INDUSTRIES".
DEVAKOTTANI KRISHNAN KRISHNA MURTHY,
K 11, SHREE DWARKA CO. OP. HOUSING SOCIETY,
OP S.T. WORK SHOP, PATIA, NARODA ROAD,
AHMEDABAD 382 345, GUJRAT, INDIA, AN INDIAN CITIZEN.
The following specification particularly describes and ascertains the nature of this invention and the manner in which it is to be performed
16 - 3 - 2004
Field of the Invention
This process relates to a process for obtaining clean water from textile processing industries
Introduction to the Field of Invention.
It is well known that a large amount of effluent water is discharged by various units of textile processing industries. For example enough effluents are discharged by;
1 Printing units
2 Cloth dyeing units
3 Yarn dyeing units
4 Hosiery dyeing units and many others
Further, several types of dyes are used in textile processing industries Conventionally used dyes for example are
1 Vinyl Sulphone dyes
2. Reactive dyes M,H, HE series
3. Rapid fast dyes
4. Napthol based dyes
5 Vat dyes
6 Pigments dyes
7. Sulpher dyes
8. Basic dyes
9. Acid dyes etc.
The quantity of effluent water and the strength of the dye in the effluent varies from each type of unit.
A large amount of coloured water is thus discharged by these units daily, which can be reclaimed and reused by removing colour
Presently, these effluents are treated using primarily lime powder and alumina (AL2S04)
These methods are time consuming and are not suited to remove all types of colours substantially Moreover, it is also not cost effective
Objects of the Invention:
It is therefore a primary object of the invention to propose an effective and simple process for the purposes of obtaining clean water from effluents of textile processing industries using easily available chemicals.
It is another object to propose such a process, which can be carried out by general work force, who has keen observation and judgement skills.
It is a further object to propose such a process, which can be carried out using cheap and non-expensive plant, which does not require heavy investment or heavy maintenance and therefore, make the process economical and commercially viable.
It is still further object to propose such a process, which can be eco-friendly and toxic free.
These and other objects can be easily understood from the following paragraphs.
Thus, according to this invention, there is provided a process for obtaining reusable clean water from effluents of textile processing industries, which comprises subjecting the effluent water to a double treatment,
(i) a pH treatment using an alkali, preferably sodium hydroxide and
(ii) a coagulator using preferably ferrous sulphate in any order or as a mixture followed
by (iii) filtering the clean water through a bed of activated carbon.
However, effective results have been obtained by first treating the effluent with the alkali followed by treatment with ferrous sulphate.
For reasons of economy and reducing the time of operation, I have found equally good results, when both chemicals are used together.
It is important to use a filtration step after the treatment step to filter the clean water and this is best carried out in a bed of activated carbon.
Use of activated carbon helps in trapping fine coagulated matters and also in the removal of any residual colour and suspended matter.
It is found that the use of the above mentioned two chemicals almost completely precipitate the colourant and other interfering chemicals suited for filtration.
I have found that the alkali should be NaOH.
The quantities of NaOH and AJ2SO4 depend upon the quality of the water to the treated and based on the following equation.
Fe S54+2NaOH > Fe (OH)2 I + Na2 804
Fe (0H)2 bring down all the dyes molecules and precipitates immediately and settles as solid waste.
In an actual laboratory study, it has been found that both the chemicals are necessary almost in equal quantities as water solutions.
I have achieved encouraging results using 2.0 to 2.5 Lts of these chemicals for treating 1000 Lts of effluent water.
The solutions of these chemicals are ideally of 1.2 to 1.3 Sp. Gravity.
However, the variation in the amount, time and Sp. Gravity are not beyond the scope of this invention.
Detail Description of the Invention:
In the accompanying figure 1, a general layout of the plant is given.
In figure 2, detail of carbon tower unit is given.
Thus, effluent water is stored in a storage tank 1, preferably in an underground facility.
Necessary quantity of the effluent water is pumped by pump 2 on the ground, to the top of a Neutsch unit 3 of the conventional type, An overflow facility unit 4 is provided on unit 3. The /V effluent water. NaOH,and ferrous sulphate.in measured quantities are dosed together into unit 4
from where it goes through unit 3. The water collection at the bottom of unit 3 is substantially colour free and is then pumped by pump 5 to the top of a activated carbon tower 6.
The water coming out of the tower 6 is clean water, which is stored in tank 7 and can be reused in the textile processing units.
The activated carbon tower 6 is supported on the ground in such a manner as to facilitate gravity flow from the top. The water from unit 5 is sprayed through nozzles or perforated pipes provided as a circular pipe 6A along the top inner wall 6B of the tower 6.
To facilitate further even distribution, a perforated top plate 6C is supported below the circular pipe 6A.
There is provided a fine cloth bag 6D packed with activated carbon 6E occupying almost the whole volume of the tower followed by bottom perforated plate 6F below which clear filtered water is collected.
For treating the effluent from Textile processing industries, Sodium Hydroxide solution (NaOH) can be added first & then ferrous sulphate solution. Also, ferrous sulphate solution can be added first & then Sodium Hydroxide solution. Both the above NaOH & ferrous sulphate solutions can also be added simultaneously. How ever, (NaOH) Sodium Hydroxide being a strong alkali, adding NaOH first & then ferrous sulphate solution gives a better results.
So, NaOH solution can be added first in the effluent collecting tank (Under ground) & then pumped as shown in the Flow diagram and at that paint ferrous sulphate solution can be added & then discharged in to the NEUTSCH for filtration.
These two chemicals remove all types of dyes from the effluent as already stated in the Report. Vat dyes, Reactive dyes, Basic, sulphur, VS based dyes, Rapid fast, Acid dyes, etc,.
As the strength of the dye (colouring matter) will not be the same in the effluent coming from different units using different types of dyes in the process to standardization is not feasible.
How ever, for treating 1000 Lts. of effluent coming from any type of textile processing industries, the approximate consumption of chemicals will be as under: -
1. Sodium Hydroxide (NaOH) 2 Lts ±5%
2. Ferrous sulphate solution 2.5 Lts+ 5%
PH of the treated effluent should be maintained at 7,0.
ADVANTAGES OF THE INVENTION.
1. It is easy to prepare the solutions of the two chemicals.
2. Handling and storage is easy. Has a long storage life.
3. Both the chemicals are easily available within jour country.
4. Activated carbon of very high quality is also available within our country.
5. Less quantity of both the TWO chemicals (Activater and Strriper) are required for treating 1000 Lts. Of effluent water.
6. Within minutes of addition of the TWO chemicals, coloured matter (Dye) separates completely from the effluent water.
7. Less quantity of solid waste will be generated as compared to LIME POWDER usage. Thus, Less Space will be required for storing solid waste.
8. No sand bed filter or any other type of filter is required.
9. Very little maintenance and attention will be required to Operate this plant.
10. Requires Less space and power for running t his plant.
11. The greatest advantage is that the treated water can be reused.
12. The above TWO chemicals removes coloured matter even if considerable salt is present in the effluent water.
13. The TWO chemicals remove all types of dyes presently used in the Textile industries.
I Claim: -
(1) A process for obtaining reasabte' clean water from effluents of textile processing industries,
which comprises subjecting the effluent water to a double treatment,
(i) a pH treatment using an alkali, preferably sodium hydroxide and
(ii) a coagulation/precipitation treatment using preferably ferrous sulphate in any order or as a mixture followed by
(iii) filtering the clean water through a bed of activated carbon..
(2) A process as claimed in Claim 1 wherein .preferably both the chemicals are dosed
together with the water to be treated.
(3) A process as claimed in claims 1 and 2, wherein filtration through a bed of activated carbon is used to help in trapping fine coagulated matters and also in the removal of any residual colour and suspended matter.
(4) A process as claimed in claims 1 to 3, wherein the quantities of NaOH and AI2SO4 depend upon the quality of the water to the treated and based on the following equation.
A process as claimed in claims 1 to 4, wherein mmf prnfrrnihly hnth the chemicals are used almost in equal quantities as water solutions.
(6) A process as claimed in Claim 5 wherein the solutions of the above mentioned chemicals are ideally of 1.2 to 1.3 Sp. Gravity.
(7) A process for obtaining rousablo cleary/vater from effluents of textile processing industries substantially as herein described with reference to the accompanying drawings.
DATED THIS THE 21st DAY OF JULY 2003.
|Indian Patent Application Number||742/MUM/2003|
|PG Journal Number||32/2007|
|Date of Filing||24-Jul-2003|
|Name of Patentee||DEVAKOTTAI KRISHNAN KRISHNA MURTHY|
|Applicant Address||K.11, SHREE DWARKA CO.OP. HOUSING SOCIETY, OPP. S.T. WORK SHOP, PATIA, NARODA ROAD, AHMEDABAD,|
|PCT International Classification Number||C02F 1/00|
|PCT International Application Number||N/A|
|PCT International Filing date|