FORM 2
THE PATENTS ACT, 1970
(39 IF 1970)
COMPLETE SPECIFICATION
1. We claim that we have dove/oped on effluent tertiary treatment
plant based on the advanced oxidation technology FOR
REDUCTION OF SUSPENDED SOLIDS, COLOUR, BOD, COD, Llgnln and
ORGANO CHLORIDE (Absorbable organic halogen) In a
biologically treated pulp-and-paper-mlll-wastewater.
This process Is capable of reducing both biodegradable and nonbiodegradable contaminants to any desired level treatment
2. WytewaterTM Technologies Pvt. Ltd.,
401 - 404, Pawan Apts.,
S.No. 121, Near Balaji Mandir, Pashan Sus Road, Pune- 411 021,India.
3. The following specification (particularly) describes fully the nature
of the Invention and the manner in which it is to be performed.
a. INVENTION
we have developed an effluent tertiary treatment plant based on the advanced oxidation technology FOR REDUCTION OF SUSPENDED SOLIDS, COLOUR, BOD, COD, Llgnln and ORGANO CHLORIDE (Absorbable organic halogen) In a biologically treated pulp-and-paper-mlll-wastewater.
This process Is capable of reducing both biodegradable and nonbiodegradable contaminants to any desired level treatment


b. PULP & PAPER MILL EFFLUENT - AN
INTRODUCTION
Pulping is a process of cellulose extraction from celluloslc materials such as wood, straw, bagasse etc.
In pulping, the raw material is 'cooked' In about 6 - 7% sodium hydroxide solution at about 165 degree Celcius and at a pressure of 6-7 kg/cm2. Under these cooking conditions, llgnln gets dissolved and the cellulose fibers get separated - forming a pulp. The pulp is then washed, bleached ft required, and then taken for papermaklng.
The wastewater generated during pulping & bleaching consists of lignln as the major pollutant that imparts black color to the wastewater.
The general characteristics of wastewater will be high BOD, high COD, high-suspended solids, Lignln and Organo-Chlorldes.
The laboratory studies Indicate that when we attempt to reduce colour automatically other parameters get reduced.
c. EXISTING WASTEWATER TREATMENT
PROCESSES
Existing processes for eliminating/reducing the above mentioned pollutants are
1. Reducing the pH below 4 for precipitation of llgnln at Llgno
sulphates.
2. Ultrafiltration membrane treatment.
3. Biological treatment - Anaerobic treatment followed by aerobic treatment.



d. EXISTING PROCESS - MERITS St DEMERITS.
I. Reducing the pH below 4 for precipitation of iignin as Ligno sulphates.
Reducing the pH do precipitate the llgnln as Ligno sulphates. But to reduce the pH below 4.0 Is not an eco-friendly process as It consumes huge quantities acid, and then again alkali to Increase the pH to neutral for discharge.
The precipitation techniques gives reduction In Llgnln, COD/BOD and up to 65% Is achieved In places. But there are no considerable reduction AOX levels. The process equipments require special consideration, as the treatment process is highly corrosive. The environment should be protected from the corrosive fumes.
This process Increases the dissolved solids content of the treated wastewater and In most in the cases the dissolved solids levels goes more than the pollution control Board limits leading to cji$posa\ problems.
Precipitation .also results In converting one form of pollution in to another and do not actually reduce the pollution.
Due to this disadvantages Lignln removal by precipitation is not practiced anywhere.


ii. Ultrafiltration 8c Reverse osmosis membrane treatment.
Ultrafiltration & Reverse osmosis is a membrane-based process and Is capital Intensive.
The paper mill effluent Is rich In organic pollutants. This will lead to frequent organic fouling.
Organic fouling results In Irreversible damage to the membrane. Frequent cleaning to remove the organic fouling reduces the life of the membrane.
The Ultrafiltration technique splits the pollutant stream In to two. The accept and the reject.
The accept Is the treated effluent and the reject Is another stream of effluent where the concentrated pollutants will be present.
The concentration of the pollutant in the reject stream depends upon the recovery with which we operate. But definitely far more than it was present In the raw effluent, There fore the reject cannot be disposed off with out further treatment.
Hence using membrane process We will be able to only reduce the volume of effluent. Hence using this technique we cannot find permanent solution.



Ill Biological treatment - Anaerob/c/ aerob/c or Anaerob/c treatment followed by aerobic treatment.
The efficiency of the blotoglcal process In reducing the pollutant load depends up on many parameters and It never exceeds more than 70 - 80%.
St means the treated effluent will still carry residual pollutants. This Is a major disadvantage In biological treatment process.
Since the treated effluent still carries some pollutant load it can not be reused and at times with out further treatment - Tertiary treatment- It may not be possible to meet the pollution control board limit also.
Biological process does not eliminate calcltarant COD.
Biological process does not remove AOX (Absorbable Halogen). With the current statutory limits of the pollution control boards for AOX - the biological process will miserably fall.
Biological process is also very sensitive to shock loads and regular shock loads wilt upset the plant performance.
Biological process Is also sensitive to environmental condition
and careful monitoring & maintenance Is required to achieve the desired objectives.
It occupies larger space.
Generates sludge, which needs further treatment for safe disposal.
e. OUR PROCESS
In place of the existing wastewater treatment process, we have developed a process - which Is a combination of a physical and
physiochemlcal process.
In our new process we use coagulation, ftocculatlon, clarification and filtration as pre-treatment to remove the suspended


lmpurities.
Chemical & photochemical oxidation and adsorption techniques
to remove the dissolved Impurities.
Thus, the treated effluent will have low flgnln, low BOD, low COD, low AOX and desired levels of purity.
f. UNIQUENESS OF OUR PROCESS
We have developed an effluent tertiary treatment plant bated on the advanced oxidation technology FOR REDUCTION OF SUSPENDED SOLIDS, COLOUR, BOD, COD, Llgnln and ORGANO CHLORIDE (Absorbable organic hatogenl In a biologically treated pulp-and-paper-mlll-wastewator.
This process Is capable of reducing both biodegradable and non- biodegradable contaminants to any desired level treatment
1. Un like membrane process -It does not generate liquid or
solid effluent of Its own while treating the effluent. What
ever Is being settled and removed, as sludge Is the
suspended solids that are coming along with the raw
effluent
2. Unlike membrane process - it does not generate any stream,
which has got stronger pollutant than even In the raw
effluent,
3. Unlike the precipitation process - It does not convert one
form of pollution In to another. The pollutants are converted
In to harm less by products such as carbon-di-oxlde and
water.
4. Unlike the biological process - the treated effluent does not
require any further treatment to re-use.
5. Unlike the biological process - The treated effluent will be
disinfected and no harmful bacteria will be present.
6. Unlike the biological process - It Is operator friendly and
echo friendly.


7. Unlike the biological process- continuous operation Is not
required. It can be operated In batch or continuous mode.
8. Unlike the biological process - Changes In the environment
do not atfect the performance.
9. Our process eliminates calcltarant COD.
10. Our process eliminates AOX and hence It Is quite safe for
discharge. (Absorbable organic halogen).
It Is now possible to reduce the pollutants like Lignln, BOD, COD, organo chloride etc to any desired levels of purity by Increasing or reducing the oxidant dosages from the pulp & Paper mill waste water.
g. TECHNOLOGY DESCRIPTION - ADVANCED OXIDATION
Advanced Oxidation Technology is a generic name for a family of oxidation technologies that use high Intensify ultra violet light directly (photolysis), or In conjunction with standard oxidants such as hydrogen peroxide (H202), chlorine etc, (photochemical oxidation) to achieve greater oxidation performance over that obtained with oxidants alone.
To oxidize a pollutant with an oxidant, both the pollutant and the oxidant need to come together, and should cross an energy barrier called the 'activation energy.'
Ultra violet light excites the pollutant molecular bonds to higher energy levels and makes the pollutant molecule more amenable to the oxidant attack. Further, the UV light also activates the oxidants. For example, when H2O2 is exposed to high Intensity UV light, It generates highly unstable hydroxy! radicals, which quickly and effectively attack the pollutants and oxidize them.
Thus, In advanced oxidation, the ultra violet radiation acts as a double edge knife. It activates the pollutants as well as the oxidants to a higher energy state thereby helping them to cross the activation energy barrier. This makes the oxidation reaction simple, effective and more complete.


h.i LIGHT AND ENERGY
Light, which Is an electromagnetic radiation, Is universally described by Its wavelength. This wavelength Is referred In "nanometer" or 10'* m and there are 10 Angstroms per nanometer.
The more fundamental quantity describing . electromagnetic radiation is its frequency of vibration. The frequency and the wavelength of radiation are related by
C = V  where
c = the velocity of light (3 x1010cm/second In free space)
v == frequency of vibration (1/sec)
 = Wave length In cm.
A number of terms are used to express the quantity of radiation.
These physical units relate to work or energy.
The most commonly used are erg, calorie and joule (watt-second); all are measures of total quantity of energy or work.
The Intensity or energy density of radiation Is expressed In terms of energy incident upon unit area. The unit used here Is the microwatt - second* / sq.cm. (uWs/cm2).
Quantum theory states that radiant energy is transmitted In discreet units, or quanta. The energy of these fundamental units is related to Its frequency. Further light can be treated not only as waves but also as flux of particles called photons. The energy of a photon, E, is related to the frequency or the wavelength as follows.
E = hv = hc / (X) Where
h - Planck's constant Equivalent to 6.62 x TO"27 erg per
second
v = light frequency,
X = Wavelength
c - speed of light.
It Is thus; smaller the wavelength of light greater Is the energy It
carries. Therefore, violet and particularly ultra violet light has
more energy than red or yellow light (visible light).


h.ii ULTRA VIOLET LIGHT
The Ultra Violet region of the electro magnetic spectrum is generally defined as those radiations that have wavelengths greater than the longest X -ray and smaller than the shortest wavelength visible to man. These wavelengths ate typically set
between 5 - 400 nm (Nanometers). The ultra violet radiation itself is divided into;
a. Extreme ultraviolet (5 - 200 nm)
b Far ultraviolet (200 - 300 nm], and
c. Near ultraviolet (300 - 400 nm).
Energy In the extreme ultraviolet region, 5 - 200 nm, Is strongly absorbed by atr and its observation requires working In a vacuum or In a gas, which does not absorb the energy.
h.iii PHOTOlYSIS
Photolysis involves Interaction of light with molecules to bring about its dlsassoclatlon Into fragments. Light is considered to travel as tiny energy particles called photons.
It the absorption of a photon Is to cause photolysis (dlsassoclatlon), the photon energy must exceed the energy of the bond that needs to be broken. This requires that the wavelengths be In the ultra violet region of the spectrum for
most photolytlc reactions.
Further, as per laws of photochemistry, the chemical effect of light Is proportional to the light intensity and exposure time. Compounds that absorb ultra violet light and have high quantum yields of photolysis are good candidates for photo degradation


Examples of these classes of compounds Include N - nlfroso dl-mythyl amine (NDMA) and various chlorinated alkanes and aromatlcs.
Direct photolysis Is especially Important for refractory
compounds such as carbon tetra chloride, chloroform,
chlorinated alkane, which react relatively slowly with hydroxyl
radicals alone.
Destruction by photolysis highlights the Importance of using ultra violet lamps with the highest possible output In the ultra violet region, where most organic toxins strongly absorb light energy and where the photolysis quantum yield (I.e. a measure of tendency to change structure) Is typically higher.
h. iv OXIDATION
Oxidation is the chemical conversion of a contaminant to
more oxygenated forms by means of reactions with oxidizing agents, such as oxygen (02), ozone (03), hydrogen peroxide (H202), or sodium hypochlorite (NaOCl). The following equation represents a general oxidation process:

The multiple arrows Indicate multi-step processes. Simple oxidation Involves the addition of oxidizing agents such as 02, 03, H203, Ca(OCI)2 or NaOCl: however, the overall oxidation rates are usually too slow and the chemical consumptions are too high to be applied broadly for wastewater treatment.


h.v.. ADVANCED OXIDATION TECHNOLOGIES (AOT)

Once generated, the hydroxy! radicals aggressively attack virtually all-organic compounds.
Depending upon the nature of the organic species, two types
ot Initial attacks are possible: the hydroxy I radical can
abstract a hydrogen atom to form water, as with alkanes or
alcohols, or It can add to the contaminant, as is the case for
olefins* or aromatic compounds.
OH


The attack by the hydroxyl radical. In the presence of oxygen. Initiates a complex cascade of oxidative reactions leading to mineralization.
As a rule of thumb, the rate of destruction of a contaminant Is approximately proportional to the rate constant for the contaminant with the hydroxyl radical. From Table 1.1 we can see that chlorinated alkenes treat mo3t efficiently because the double bond is very susceptible to hydroxyl attack. Saturated molecules (i.e. alkanes) have much smaller rate constants, and therefore are more difficult to oxidize.
There ore several methods for generating hydroxyl radicals that can be utilized. These Include both photochemical and non-photochemical methods,
h.vi PHOTOCHEMICAL OXIDATION OR UVfOXIDATION
There are many different ultraviolet light-enhanced treatment processes available. The following are the two most common.
h.vii. PHOTOLYSIS OF OZONE
03 + hv + O ('D)
O('D) + H20 -> (2.OH) -> Ha02
In aqueous solution, photolysis of ozone has been shown to lead to hydrogen peroxide In quantitative yields. Photolysis of ozone therefore appears only to be an expensive way to make hydrogen peroxide that Is subsequently photolyzed to .OH radicals. The use of ozone can be quite effective from an operating cost standpoint, especially for waters with high background UV absorbance, but capital cost, stripping, ozone destruction, and health and safety problems can make ozone less desirable.


h.vlll PHOTOLYSIS OF HYDROGEN PEROXIDE
In the UV/Peroxide process, a high-powered lamp emits UV radiation through an AFP™ tube into the contaminated water. Hydrogen peroxide is added, which Is activated by the UV tight to torm oxidizing hydroxy! radicals:
H202 + hv -> 2.OH
The following equation represents the simplified statement of the oxidation process:
Chlorinated 02 Intermediates Q2
Organic Molecule ->-»-» (aldehydes/
-»->-»C02 + H20 + CI'
OH Carboxylic acid)
if afiowed to proceed to completion, the end products are rnafnty carbon dioxide and water, with small amounts of chloride, nitrate, or sulfate Ions depending on the contaminants. This oxidative treatment ts called mineralization of the dissolved contaminants and means that secondary pollution or waste disposal Is not required, A UV/OxIdatlon system can be designed to meet any discharge requirement.



I. PILOT PLANT TRIALS
SOURCE OF EFFLUENT
The Inlet to the plant Is the treated etfiuent from an existing effluent treatment plant that consists of treatment on digester effluent (black liquor) and bleaching (bleach liquor).
The black liquor Is sent to anaerobic digester (blomethanatlon plant) tor blogas generation. Sludge from the blomethanatlon plant Is sent to drying beds, and the overflow is collected In a tank.
The bleach plant effluent 1$ blended with the overflow from the blomethanatlon plant, and the blended effluent Is given following treatment.
1. Primary Clarifler - to reduce suspended solids
2. Aeration tank for biological treatment
3. Secondary clarifler - to remove blosollds generated In the aeration tank
The overflow from the secondary clarifler is the inlet to the pilot plant.
J. OUR TREATMENT
Process flow sheet Is enclosed herewith In form of a block
diagram, and the scheme Is explained below,
1. Overflow from the secondary clarifler Is collected In a tank
where mixing is provided to even out the fluctuations in the
incoming effluent (secondary clarifler outlet). This Is called
as equalization.
2. The equalized effluent Is dosed with coagulating and flocculating chemicals, namely polyaluminum chloride and anionic polymer to trap the turbidity and suspended solids.
3. The coagulated and flocculated effluent is fed to a clarifler.


K. PILOT PLANT SPECIFICATIONS
1. Plfot Pfant Flow rate Mln.500 liter/hour
Max. 1750 liter/hour
2. Coagulant PolyAlumlnlumChlorlde
Dosage Min.500 ppm
Max..750 ppm
3. Polymer Betz Dearborn AEU25 (anionic
_ polymer)
Dosage
Mln.l.G ppm Max.3.0ppm
4. Equalization tank 2000 Its.
capacity 0 6 hp
Blower capacity
5. Dimensions of the 800 mm dia x 2500 mm HOS
claritler 45 to 90 minutes
Retention time In the Manul at regular interval
clarlfler


clarlfler 600 Lts
De-sledging Manual - Once Is an Hour.
Capacity of the clarified 500 Lts.
effluent collection tank
6. Sand filter dimension 300 mm dia x 1500 mm HOS
Filtering medium Graded sand
Operating Pressure 2.0 kg/cm2
Design specific velocity 9.0 m3/hr/m2
7. Bag Filter 0.5 m3/hr
Bag Filter Rating 10 micron
8. Oxidant Calcium Hypochlorite
Strength 28 gram/liter
Dosage Min. 1 00 ppm on Available Cl2
basis
Max.300 ppm on Available Cl2 basis
9. Photochemical Reactor
Type Flow through Transparent
tubes. No. of tubes
No. of lamps
Watt/lamp 6
75 Resident time In the
reactor 1.0 to 3.5 seconds
10 Reaction Tank no, 1 Volume 500 Lts.
Retention time In the tank Mln.20 nrits. Max.60 mts
M.O.C H.D.P.E
1 1 Reactor Volume 50 Lti:.
Retention time In the Mln.5.0 mts Max15.0
reactor
M.O.C S.S.316
12 Carbon filter 300 mm dla x 1500 HOS
Filtering medium Carbon
Operating Pressure 2.0 kg/cm2
Design flow rate 9.0 m3/hr/m2


/. SAMPLING
The plant is being operated for about 10 hours everyday. Samples sent for analysis are composite samples. Each composite sample Is collected as follows.
200 ml of sample is collected every hour and over at the end of the day's operation of 10 hours, a total volume of 2000 ml of sample gets collected. The total days volume Is mixed In separate containers and from the mixed sample - a volume 1000 ml was sent for analysis. Samples were collected at pilot plant inlet and pilot plant outlet.
Parameters analyzed
I. BOD
II COD
III. Suspended Solids
Iv. Colour
v. AOX
m. TRIAL RESULTS


17




n. CONCLUSION
While carefully scrutinizing the achieved results It Is evident that the advanced oxidation technology using Photochemical reactors helps In consistently eliminating/reducing the colour, calcttarant COD, BOD, Llgnin, and Organochloro compounds.
It can now be possible for us to design and construct a plant of any size and capacity for reducing/eliminating Ugnln, COD, BOD, color and Organo-chlorlde in a pulp and paper mill wastewater.
OUR CLAIM
We claim that we have developed an effluent tertiary treatment plant based an the advanced oxidation technology FOR REDUCTION OF SUSPENDED SOLIDS, COLOUR, BOD, COD, Ugnln and ORGANO CHLORIDE (Absorbable organic ha login} In a
biologically treated pulp-and-paper-mlll-wastev/ater.
This process Is capable of reducing both biodegradable and nori - biodegradable contaminants to any desired level treatment
This will bring down the ultimate pollution levels In the treated
effluent that Is currently being discharged Into rivers and lakes.
As per the recent Pollution Control Board notification, the
permissible AOX levels to be achieved within 12 months from
March, 2003 should be 1.75 kg/ton of paper produced In the first
two years and thereafter 1.5 kg/ton In the next three years. Only our
process is capable of achieving this.
i



Once Industries start adopting process like ours - the threat of survival to Industries on account of pollution shall come down and the Industries can confidently look towards growth.