FORM 2
THE PATENTS ACT, 1970;
[39 of 1970]
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION: [SECTION - 10; RULE 13]
A METHOD AND AN APPARATUS FOR RECOVERY AND TREATMENT OF WASTE INDUSTRIAL COOLANT FOR RECYCLING & REUSING.
WYTEWATER TECHNOLOGIES
PRIVATE LIMITED, a company
incorporated under the
Companies Act, 1956, having registered office at 401-404, 41h Floor, Pawan Apt., S. No. 121, Pashan Sus Road, Pashan.PUNE-411021, Maharastra, India.
The following specification
particularly describes the
invention and the manner in which it is to be performed:

This invention relates to a method and an apparatus for recovery and treatment of waste industrial coolant for recycling and reusing.
It was a discovery by F.W.Taylor [an American
Engineer] that the rate of machining could be greatly
increased if a stream of water kept the cutting
surface cool. The gradual developments and
advancement showed that water as a cutting fluid is
less efficient in metal wetting and rapidly rusts the
steel, it has high heat capacity due to high specific
and latent heat. The development and
advancement evolved an emulsion of "oil" in "water" as cutting fluid in machining operations.
There are numerous grades of cutting fluids, adheres optimum use of the tool and precision in finish on the job being machined. In selecting the cutting fluid for a specific operation, the factors, such as, the tool material, work-piece material, cutting speeds and severity of operation needs to be taken into consideration.
It is considered that a good quality cutting fluid must have good emulsion stability during storage; easy emulsification characteristic with different sources of water; good wetting characteristics so as
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our behalf in connection with filing of Patent applications for new inventions and prosecuting patent applications on our behalf in respect of various inventions and doing all acts necessary to put the applications in order for acceptance and renewals from time to time and request that all notices, requisitions and communication relating thereto may be sent to such person at the above address unless otherwise specified.
We hereby revoke authorizations issued in the matter of our Patent Application Nos. 296/MUM/2003 and 1096/MUM/2005.
Dated this 8th day of July, 2006.


To:
Controller of Patents
Patent Office,
Mumbai.

For WYTEWATER TECHNOLOGIES PVT. LTD.

to have effective heat transfer from the metal; free of 'foam' during usage; sticking resistant; protect work piece, tool, and machine components from rusting; and chip, metallic particles and grinding swarf to settle rapidly.
Almost every job work in engineering industries
require use of coolants, which is with 4 to 5%
concentration by continuously recycling in the
machine, and in the process the coolant gets
contaminated with (i) metallic particulate; (ii)
abrasive particulate; (iii) water salt particulate; (iv)
Biological degradation particulate; (v)foreign
contamination particulate; (vi) coolant interaction particulate. Coolant is expensive and supply of fresh batch of coolant continuously severely affects economy. The contaminations occurred results in change in the coolant property, which may damage the machine bodies, and therefore, it becomes unfit for further use. The contaminated coolant generates foul smell, which will be unpleasant resulting in inefficiency of workmen. Further more, discharge of contaminated coolant causes atmospheric disastrous. In order to be economical and atmospheric friendly, it is highly recommended that contaminated coolant is recovered, treated and recycled continuously as many times as possible, before it is finally discharged as "waste".
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Upon continuous usage in the machine -generally soluble cutting oils needs replacement primarily due to offensive odor and different type of particulate matters each having a deterrent effect on the coolant performance.
Cutting fluids are generally contaminated with -
Metallic particulate generated due to the machining operation and in excess interfere in coolant transfer and choking of the nozzles;
Abrasive particulars, a variety of grinding materials are used in various operations such as bearing grinding, boring, lapping etc. The complex structure of these abrasive wheels results in generation of variety of different particles - which are foreign bodies - that does not go well with the coolant characteristics;
Water - salt particulate from water sources from different places have a variety of impurities of different concentrations. The impurities are a combination of various Cation and anions -which are inorganic in nature and contribute to the "total dissolved solids" in water. On continuous recycling of the coolant, these salts get concentrated due to evaporation of the diluted water - when the cutting fluid comes in contact with the hot machining surface. Such build up of dissolved solids will have higher salt
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concentrations have been noticed to increase. Pseudomonas growth. Large concentrations of hardness cations and other dissolved solids can lead to the instability of the emulsion and precipitation of insoluble materials.
Biological degradation particulate known as microbes consume millions of molecules of lubricant, emulsifier, and rust inhibitor etc from the coolant. When spoilage occurs, often the emulsion may break. This coolant degradation may result in quantities of insoluble materials and biological by -products. The microbial growth also results in production of Hydrogen Sulfide gas, which can react with ferrous ions to form a black precipitate of iron sulfide - which causes emulsion to appear to gray to blue gray.
Another physical effect of microbial degradation is the corrosion of metal by either or any of the following:
i. Production of corrosive metabolic byproducts
ii. Destruction of rusts protective films and inhibitors.
iii. Many circulation systems are constructed of concrete, which are subject to microbial deterioration, and such concrete tanks actually become a place and source for
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the continued degradation of the metalworking fluid
Foreign contamination particulate, such as floor sweepings, trash, oils, detergent solutions. These foreign contaminations greatly affect the coolant collection and distribution system.
Cooling interaction particulate is basically a fluid with an oil phase and a water phase held together in an emulsion by surface-active emulsifying material.
The coolant is a dynamic equilibrium system. The coolant product has been designed to perform under specific metal working application criteria. Being a dynamic equilibrium chemical system, the coolant is subject to balance changes due to contamination with in the system, which results in coolant interaction.
For an example one such interaction is the reaction of the coolant with water - since the major ingredient of coolant is water. High concentration of cations such as calcium, magnesium, iron etc is considered hard.
This cation will interact with the coolant emulsifying materials to form insoluble calcium scums.
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With iron present, the formation of iron hydroxide slime may also result from the addition of the alkaline coolant.
These interactions greatly affect the quality of the emulsions in a fluid mix and may cause other coolant components such as oil, additive materials, etc to become incompatible with the emulsion.
Contaminated coolant has no usefulness in the industry and is therefore, discharged after treatment. Hitherto known process for treating the contaminated coolants is elaborate, inefficient and generates huge amount of metallic sludge and the spoiled mineral oil. The separated mineral oil cannot be used back and that too needs to be discharged, leading to economical loss.
A wide variety of industries - in particular Engineering industries - generate millions of liters of oily wastewater daily as shown below:
Oil wastes is derived from general metal working water soluble coolants, cutting, grinding, oils, and lubricants used in machining operations.
Discharges from parts washer tanks, rinse waters and floor washings
Primary Metal Rolling and drawing oil used
as lubricants and coolants
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Waste Collections
Food Processing
Transportation
Textiles

in ferrous and non-ferrous operations.
Emulsified and water-soluble oil wastes haulers from other industries.
Natural fats and oils from
animal and plant
processing, particularly
vegetable oily wastes.
Oil waste discharges from
tank car cleaning
operations.
Natural oils from wool scouring, fabric finishing oils.

Free oil may be readily removed by mechanical separation devices, which use gravitational forces as the driving force.
Unstable oil/water emulsion may be mechanically or chemically broken, then gravity separated.
Stable emulsions, particularly water-soluble oily wastes, require more sophisticated treatment to meet toadies effluent standards.

Conventionally, the standard chemical treatment resulted in a sludge in which the dirt, floe and trapped water remained with the oil phase. This sludge always required further stabilization before disposal. The water phase from chemical treatment needed additional treatment to meet environmental standards for discharge into a sewer. Owing to these cumbersome and ineffective conventional treatment processes - treatment of the highly stable oil/water emulsions always lead to complications.
With above among other objects in mind, the present invention evolves a five-stage process based on the principles of Photochemical Oxidation in recovering the waste coolant. According to the invention the recovered coolant is restored almost the quality of fresh coolant and put back in operation the same way that from where it was discharged. The whole process evolved in accordance with the present invention keeps on continuing for number of cycles.
Recovering and recycling the waste coolant brings in following advantages to use industries:
Consumption of fresh mineral oil for coolant preparation is drastically reduced there by bringing is better operating economics.
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Drastic reduction in waste coolant discharge to the effluent treatment plant there by reducing the operating cost of the effluent treatment.
Constant quality of recycled coolant.
Eco-friendly process.
Operator friendly.
Adopting this process not only helps in conserving the environment also helps the used industry to go in for ISO 14000 certification and also helping the user industries to fulfill their social commitments.
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Highly stable oil/water emulsions - generally referred to "Coolants" by the industrial user - are also known as "Metal working fluid ".
This is a Thermic fluid used in Machines to transfer heat generated during the process of metal cutting & drilling operations.
Cutting oil - generally of organic nature and - is diluted with water to 4 - 7 % concentration before being used in machines as "Coolant".
Coolant - on continuous usage in the machines gets contaminated with different types of particulate matters.
The particulate - in the contaminated coolant either interfere in the heat transfer efficiency during metal finishing or results in biological fouling and degradation causing health hazards such as skin irritations and also bad smell.
When the coolant is contaminated with all or with some of the particulate matter - the coolant needs to be replaced. And this is the source for the waste coolant.
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Conventional coolant treatment is a Physio-chemical process - where reducing the pH with mineral acids break the stable coolant emulsion.
The free-floating oil - obtained by breaking the emulsion is skimmed off and the sludge generated in this process is discharged for land filling.
The major disadvantage of the conventional process is huge consumption of corrosive chemicals and the large amount of sludge being generated.
In addition to this and like in any other Physio-Chemical process - many parameters of the waste coolant generation need stricter monitoring to achieve better characteristics for treating.
Inefficient treatment on fluctuated inlet conditions.
Requires huge amount of barren land to dump the sludge.
Not an Eco friendly process - consumes corrosive chemicals.
Meeting discharge standards and ISO certifications may not be possible.
Does not recover anything - neither water nor coolant.
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With a view to overcome cumbersome treatment of oily waste by conventional process - the coolant has to be recycled.
In order to recover and recycle the coolant -the coolant has to be treated to eliminate the contaminants; and the property that it had lost due to contamination has to be brought back.
Coolant gets contaminated with 6 type of particulate matter, which affects the property of the coolant. Hence in order to get back to original freshness, all these particulate matters have to be eliminated.
The method envisaged according to the present invention comprises of collecting contaminated coolant into a skimming tank; [either manually or through a barrel pump]; trapping the free floating tramp oil on the surface of the coolant; scrapping the trapped tramp oil from the skimmer surface; pumping the resultant coolant to an Oil Trace Remover and traping the traces of the tramp oil that consists of escaped skimming; trapping the abrasive particulate, metallic particulate and foreign particulate matter after passing the Oil Trace Remover through a filtration medium; discharging resultant coolant to Coolant Collection Tank;
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eliminating biological contamination, which results in foul smell and breaking of the oil emulsion; splitting the coolant emulsion in two phases - concentrated emulsion and the water phase; draining the water phase and collecting concentrated emulsion as reject and re-circulating the treated coolant through the Photochemical Reactor till the required purity and property are achieved.
In accordance with present invention, the apparatus comprises of at least one skimming tank housing a rotating oil skimmer having trapping means for trapping of free floating tramp oil on the surface and for the trapped tramp oil is further scrapped from the skimmer surface; the outlet from the Oil Skimmer is pumped to an Oil Trace Remover wherein it traps the traces of the tramp oil that has escaped skimming; the waste coolant after Oil Trace Remover is passed through Filtration Medium, capable of trapping the abrasive particulate, metallic particulate and foreign particulate matter and then it goes to Coolant Collection Tank; Photochemical Reactor eliminates the biological contamination that is responsible for foul smell and breaking of the oil emulsion. Additionally it also protects Oil Concentration System from biological fouling; from the Coolant Collection Tank, the coolant is pumped through a Coolant Concentration System; the Coolant Concentration System splits the coolant emulsion in two phases -
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concentrated emulsion and the water phase; the water phase will be drained; and the concentrated emulsion is collected as reject and is re-circulated through the Photochemical Reactor till the required purity is achieved.
Accompanying flow-chart is an illustration of the method and apparatus according to the present invention, which in any manner is not meant to restrict the scope of the invention. Scope and ambit of the invention extends to the claims appended hereto.
The illustration in the accompanying flow-chart, numerals 01 shows a oil skimmer, 02 is a skimming tank, which receives contaminated coolant from oil skimmer 01 either manually or through a barrel pump (not shown) and Free-floating tramp oil on the surface of the coolant is trapped that consists of escaped skimming. Resultant coolant in 02 is pumped to an oil trace remover 03. Resultant coolant is passed through filtration medium 04 to trap the abrasive, metallic and foreign particulate matters. The resultant coolant is found to have foul smell. This coolant is passed through a photochemical reactor 05, to eliminate the foul smell and then the resultant coolant is discharged into a coolant collection tank 06 and in turn the coolant is sent to a coolant concentration system 07. The coolant concentration
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system has at least one drain (not shown) for draining removed water and another outlet (not shown) for discharae of concentrated coolant for reuse.
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We Claim:
1. A method for recovery and treatment of waste industrial coolant for recycling and reusing comprises steps of collecting contaminated coolant into a skimming tank; [either manually or through a barrel pump]; trapping the free floating tramp oil on the surface of the coolant; scrapping the trapped tramp oil from the skimmer surface; pumping the resultant coolant to an Oil Trace Remover and traping the traces of the tramp oil that consists of escaped skimming; trapping the abrasive particulate, metallic particulate and foreign particulate matter after passing the Oil Trace Remover through a filtration medium; discharging resultant coolant to Coolant Collection Tank; eliminating biological contamination, which results in foul smell and breaking of the oil emulsion; splitting the coolant emulsion in two phases - concentrated emulsion and the water phase; draining the water phase and collecting concentrated emulsion as reject and re-circulating the treated coolant
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through the Photochemical Reactor till the required purity and property are achieved.
2. An apparatus for recovery and treatment of waste industrial coolant for recycling and reusing as claimed in claim 1, comprises of at least one skimming tank housing a rotating oil skimmer having trapping means for trapping of free floating tramp oil on the surface and for the trapped tramp oil is further scrapped from the skimmer surface; the outlet from the Oil Skimmer is pumped to an Oil Trace Remover wherein it traps the traces of the tramp oil that has escaped skimming; the waste coolant after Oil Trace Remover is passed through Filtration Medium, capable of trapping the abrasive particulate, metallic particulate and foreign particulate matter and then it goes to Coolant Collection Tank; Photochemical Reactor eliminates the biological contamination that is responsible for foul smell and breaking of the oil emulsion.
3. An apparatus for recovery and treatment of waste industrial coolant for recycling and reusing as claimed in claims 1 and 2
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and as described hereinabove with reference to the flow-chart.
Dated this 2nd day of August 2006.


ABSTRACT OF THE INVENTION
A METHOD AND AN APPARATUS FOR RECOVERY
AND TREATMENT OF WASTE INDUSTRIAL COOLANT
FOR RECYCLING AND REUSING
In the method and apparatus for recovery and treatment of waste industrial coolant for recycling and reusing by collecting contaminated coolant into a skimming tank, trapping the free floating tramp oil on the surface of the coolant, scrapping the trapped tramp oil from the skimmer surface, pumping the resultant coolant to an Oil Trace Remover and traping the traces of the tramp oil, trapping the particulates matter after passing the Oil Trace Remover through a filtration medium, discharge of resultant coolant to Coolant Collection Tank, doing away foul smell by elimination of biological contamination and breaking of the oil emulsion, splitting the coolant emulsion in two phases of concentrated emulsion and the water phase, draining the water phase and collecting concentrated emulsion as reject and recirculating the treated coolant through the Photochemical Reactor.
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