DESC:FIELD OF INVENTION

The present invention relates to the field of automobile manufacturing. In particular, the present invention relates to the first stage of pre-treatment line in an automobile paint shop. More particularly, the present invention relates to a system for separating oil from degreasing chemicals used during pre-treatment of automobile bodies in the paint-shop of an automobile manufacturing plant.

BACKGROUND OF THE INVENTION

In a paint shop of an automobile manufacturing facility, the pre-treatment line is the first process for thoroughly cleaning the automobiles, e.g. car body shells received from the body shop. These body shells are cleaned both from outside and inside and made ready for paint application in the paint shop.

The pre-treatment process in the paint shop is one of the main processes for cleaning and coating the vehicle bodies with a corrosion resistance layer. During the degreasing process, BIW bodyshells are thoroughly cleaned to ensure that these are completely free from oil, dirt and loose burrs.

Normally, the degreasing zone consists of at least two stages, i.e. the first stage is the spraying stage usually referred to as the knock-off-degrease (K.O.D.) which followed by a second stage or dip stage. The twin-stage degreasing process has the advantage that a major portion of oil, dirt etc. are removed by the impact of a high-pressure spray in the first stage, thus leaving relatively lower load for cleaning in the second dip stage.

The degreasing zone (Figure 1) consists of three stages, which include two spray stages and a dip stage for more efficient cleaning of the bodyshells. During the cleaning process, after cleaning of the bodyshells and dipping the same in the tank, all dirt and oil is removed from the bodyshells and gets saturated in the degreasing chemical bath by increasing the oil content therein.

Preferably, continuous oil separating systems should be installed for high-volume production of the pre-treatment line. The following points should be noted for better understanding of the effect of increasing the oil content in the degreasing chemicals:

- The effectiveness of degreasing action reduces with an increase in oil content, thus causing severe ill-effects on the paint coating on bodyshells.

- It leads to failure of further adhesion of Phosphate and ED paint coatings.

- Finally, it results in a premature corrosion and rusting of bodyshells.

- It also causes quality defects, such as flow marks on CED coatings requiring repairs thereof before the final painting of the bodyshells.

Therefore, for maintaining the properties of the degreasing bath, the separation system is attached to the degreasing bath for separating oil from the degreasing bath. The characteristics of the degreasing bath are very important.

Normally, two types of degreasing chemical baths are used for the degreasing system in the pre-treatment line of an automotive paint-shop, i.e. an emulsifying type degreasing bath and a non-emulsifying type degreasing bath. Emulsifying type degreasing bath Includes chemical that does not allow separation of oil from the bath. This is because of the addition of a definite percentage of additive (surfactant) therein. Whereas, non-emulsifying type degreasing bath includes chemical that allows a separation of oil from it and this separated oil floats on top of the bath. No surfactant or additives are added in this chemical.

PRIOR ART

Patent publication no. US 4802978 A discloses an oil water separator is disclosed having a vertical, cylindrical tank with a plurality of corrugated, oleophilic plates. A corrugated diffusion baffle is located adjacent an oil-water mixture inlet to remove the larger particulate material from the mixture and to cause coalescing of the larger oil droplets. The flow of the oil-water mixture proceeds generally in a vertical direction and passes between the corrugated plates to cause further coalescing of the oil droplets. A separate oil channel directs the coalesced oil to an upper portion of the tank. The clarified water then passes downwardly to a clean water outlet. A second coalescing unit may be located upstream of the clean water outlet to further coalesce and remove the smaller oil droplets. In this case, a second oil relief channel directs these coalesced oil particles to the upper portion of the tank, from which the oil may be removed.

Utility model publication no. CN 201823396 U discloses a dirty oil filtering device comprises a filter, wherein the filter comprises a pre-filter and an oil-dirt separator; and a high-pressure water pump is arranged between the pre-filter and the oil-dirt separator. The benefits are as follows: dirty oil is filtered by the pre-filter and then dirt and oil are separated from each other by the oil-dirt separator; in addition, the separation of oil and dirt is assisted by the pressure supplied by the high-pressure water pump; and the dirty oil filtering device has simple structure, smaller volume, lower manufacturing cost and lower cleaning-maintenance cost, and is easy to operate.

Utility model publication no. CN 204447407 U discloses an oil-water separator. The oil-water separator is composed of a bucket body, an oil-phase and water-phase input pipe, an oil-water separation net film, separation plates, a supporting plate, a water-phase collection chamber, an oil-phase output pipe and a water-phase output pipe, wherein the oil-water separation net film is a super-hydrophilic/underwater super-oleophobic net film. By virtue of the oil-water separator disclosed by the utility model, the defects of a traditional oil-water separator that the energy consumption is high, the size is large, the weight is high, the cost is high, the separation effect of oil-water separation equipment is not good, the production automation degree is relatively low and the like are overcome; the oil-water separator has the advantages of energy conservation, environmental friendliness, high efficiency, low cost, capability of working continuously and the like; the plurality of layers of separation plates are arranged in the device so that a water phase and an oil phase are separated for a plurality of times and the high-purity separation effect is realized, and the oil-water separation is finally realized; and a super-hydrophilic/underwater super-oleophobic material functional separation film is utilized so that the design is relatively novel, the application effect is relatively good and the practicability is good.

Patent publication no. CN 103611335 A discloses a corrugated plate, and an oil-water separation system and method. The corrugated plate is wavy and can quickly and efficiently remove oil dirt from degreasing liquid by adopting a hazen shallow pool theory instead of frequently replacing the degreasing liquid, so that the production cost is reduced. The oil-water separation system can enhance the oil dirt removal effect through the corrugated plate, so that the concentration of the oil dirt in a main tank body is kept at a low level, and the quality of a product is improved; furthermore, the oil-water separation system is free from energy consumption and spare part replacing, so that the service life of the oil-water separation system is long; and therefore, the service life of the main tank body can be prolonged, and the emission times are reduced; moreover, the running cost and the maintenance cost are saved, and the production cost is reduced.
DISADVANTAGES WITH THE PRIOR ART

The applicant’s automotive paint-shop has emulsifying type degreasing bath and thus oil removal is possible only by a centrifuge type separator or by heating the bath above 80°C. The existing centrifuge arrangement continuously faced problems like plate choking and therefore, it often went under maintenance due to fine dirt/muck getting deposited in the multi-plate passage. This centrifugal oil separator required 7.5 KW motor for continuous operation at 2800 rpm and the heating of the degreasing bath chemical (volume 122 m3) to this 80°C temperature also costed more energy outlay. This heating type oil separator arrangement also required more energy. Therefore, maintaining the oil content below the prescribed limits as per the relevant specifications was quite difficult and costlier process.

Although, other oil separators (e.g. floating oil tray type) are also available in the market for replacing non-emulsifying degreasing chemical, often these necessitate a complete change of the very expensive degreasing chemical.

Therefore, there is an existing need for configuring an improved oil separating system for a degreasing chemical bath, for separating oil and dirt in one single stage and which operates as a combination of oil separator and dirt settler.

OBJECTS OF THE INVENTION

Some of the objects of the present invention - satisfied by at least one embodiment of the present invention - are as follows:

An object of the present invention is to provide a low-cost oil-separating system for the degreasing bath in automotive paint shops.

Another object of the present invention is to provide an energy-efficient oil-separating system for the degreasing bath in automotive paint shops.

Still another object of the present invention is to provide a compact oil-separating system for the degreasing bath to save floor space in paint shops.

Yet another object of the present invention is to provide a low-maintenance oil-separating system for the degreasing bath in automotive paint shops.

A further object of the present invention is to provide an oil-separating system for the degreasing bath in automotive paint shops, having low-operating cost.

A still further object of the present invention is to provide an oil-separating system for degreasing bath providing low-oil content in degreasing chemical.

These and other objects and advantages of the present invention will become more apparent from the following description, when read with the accompanying figures of drawing, which are however not intended to limit the scope of the present invention in any way.
SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a system to separate oil from a contaminated mixture thereof with a degreasing chemical to be used for pre-treatment of vehicle bodies in paint-shops of automobile manufacturing plants, the system comprising:

• a multi-chamber oil separator tank having an inlet on one side thereof for supplying the mixture of dirty degreasing chemical and oil; and an outlet on the other side thereof, for removing the clean degreasing chemical;

• a baffle plate arrangement having a plurality of baffle plates disposed inside the tank;

• an oil settling tank for collecting oil and degreasing chemical separated from dirt/muck/sludge present in the mixture;

• an oil collection tray disposed in the tank;

• a clean degreasing chemical tank with an outlet disposed at the other side of the oil separator tank; and

• an oil collection tank for collecting oil separated from the mixture;

wherein the baffle plate arrangement comprises a plurality of baffle plates disposed parallel to each other and inclined with respect to the horizontal plane for separating the oil, dirt and degreasing chemical present in the mixture in separate chambers of the multi-chamber oil separator tank.

Typically, the baffle plates are made of oleophilic material and configured with corrugations to attract oil and repel water, the inclination of the baffle plates increases the surface contact time of the mixture therewith and reduces the velocity of oil separating therefrom accumulating as separated oil bubbles floating to the top of the tank and formed as large oil drops; the dirt striking the corrugations and dropping down as separated dirt to the bottom of the tank; and the mixture of oil and degreasing chemical moving forward towards the oil collecting tank for further separation into oil overflowing into the oil collection tray and clean degreasing chemical flowing into the clean chemical tank.
Typically, the multi-chamber oil separator tank comprises a main tank for installing the baffle plate arrangement; an oil settling compartment having an oil collection tray disposed therein; and a clean degreasing chemical collection tank with a vertical level balancer pipe fitted at the bottom centre thereof and sharing a common wall with the oil settling tank.

Typically, the multi-chamber oil separator tank comprises a hopper disposed at the bottom thereof, preferably having a truncated conical shape; and equipped with drain valve, preferably a butterfly valve for draining out at regular intervals, the dirt/muck/sludge separated from the mixture and collected at the bottom of the tank during the cleaning of the oil separator tank.

Typically, the vertical level balancer pipe is fitted in the clear chemical collection tank, preferably fitted from outside the bottom thereof; the vertical pipe allowing to adjust the level of the clean degreasing chemical flowing from the baffle plates arrangement to the oil settling compartment to help collection of the oil floating in the oil collection tray; and a clear chemical transfer pump fitted downstream thereof for transferring separated clean degreasing chemical to a dip-degrease tank.

Typically, the oil collection tray comprises a drain line fitted with a ball valve for controlling the collected oil flow and carrying the collected oil to the main oil collection tank.

Typically, the oil collection tank comprises the oil settling compartment with an inclined inflow side disposed parallel to and level with the arrangement and with a gap therebetween for overflowing the dirt-free oil and chemical mixture into the oil collection tank; an oil guide to lead oil from the mixture into the oil collection tray; and an outflow side of the tank made common with the inflow side of the clean degreasing chemical collection tank.

Typically, the outlet of the multi-chamber oil separator tank configured on the other side thereof is provided on the wall thereof common with the clean degreasing chemical collection tank.
Typically, the inlet of the multi-chamber oil separator tank comprises:

• a solenoid valve (A), preferably an electro-pneumatic valve fitted upstream the inlet thereof;

• first on/off float sensor (B) for the clear chemical transfer pump, and a second high-level alarm sensor (C) fitted in the clear degreasing chemical collection compartment; and

• a floating oil high-level sensor (D) fitted in the separated oil collection tank.

Typically, the multi-chamber oil separator main tank is made of mild steel and comprises the baffle plate arrangement with a plurality of baffle plates disposed parallel to each other and inclined with respect to the horizontal plane, preferably making an angle of 600 for separating the dirt from the contaminated mixture of oil and degreasing chemical in separate chambers, and thereof.

In accordance with the present invention, there is also provided a process for separating oil and dirt/muck/sludge from the mixture of oil and degreasing chemical by means of the aforesaid system, the method comprising steps of:

• supplying the mixture of the contaminated degreasing chemical (DC) and oil by gravity from the tank side-tray to the oil separator tank via solenoid valve (A);

• contacting the mixture with the inclined baffle plates having affinity for oils and non-affinity for water;

• separating the oil particles from the mixture by gradual enlargement thereof by forming bubbles to rise to the top of the liquid surface in the tank as large oil drops;

• separating the dirt particles/muck/sludge from the mixture by striking the inclined baffle plates and dropping down the separated dirt/muck/sludge particles as settled muck/sludge at the bottom of the hopper and draining out thereof at regular intervals during cleaning of the oil separation tank;

• separating the clear degreasing chemical by flowing through the baffle plates and leading the same towards the vertical pipe by entering through the bottom thereof and collecting the clear degreasing chemical in the clear chemical compartment;

• accumulating the floating mixture of separated oil drops and degreasing chemical and overflowing the mixture into the oil settling compartment;

• separating oil from the mixture of by oil guide as clear oil by passing the same to the oil collection tray for subsequent removal to the oil collection tank; and

• passing the clear degreasing chemical from separated in the oil collection tray for collection in the clear chemical compartment for final pumping by means of a clear degreasing chemical pump to a dip-degrease tank.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will be briefly described with reference to the accompanying drawings.

Figures 1 illustrates a schematic layout of the pre-treatment line for thorough cleaning of automobiles, e.g. car body shells in any automobile painting shop.

Figures 2a-2e illustrate the working of a conventional centrifugal oil separator used in present system.

Figure 2a schematic front cross-section of a conventional self-triggering centrifugal oil separator.

Figure 2b shows contaminated degrease chemical DC starting to fill inside the portion provided with the multi-plate passage of the conventional oil separator.

Figure 2c shows the heavier contaminated oil particles starting to accumulate on the circumference of the conventional oil separator due to centrifugal force.

Figure 2d shows the heavier contaminated oil particles accumulated on the circumference of the conventional oil separator due to the centrifugal force.

Figures 2e shows the oil particles and sludge discharged through the vent provided in the conventional oil separator on reaching max. preset pressure.

FIGURE 3 shows repetition of process of Figs. 2c-2e and situation inside the conventional oil separator after discharge of contaminated oil particles/sludge.

Figure 4 shows a schematic diagram of the oil separator mechanism configured in accordance with the present invention.

Figure 5 shows an enlarged partial view of the oil separator mechanism marked by encircled potion T in Figure 4.

DETALED DESCRIPTION OF THE ACCOMPANYING DRAWINGS

In the following, the system to separate oil from degreasing chemical and configured in accordance with the present invention will be described in more details with reference to the accompanying drawings without limiting the scope and ambit of the present invention in any way.

Figures 1 illustrates the layout of the pre-treatment line for thorough cleaning of automobiles, e.g. car body shells received from the body shop in any automobile manufacturing plant. The pre-treatment process sequentially includes the following process steps: Pre-grease B10, dip-degrease B20, water rinse (01 RC 1) B30, water rinse (02 RC 2) B40, activation B50, phosphate B60, water rinse (03 RC 3) B70, DM water rinse B80, passivation B90, dip DM water rinse (05) B100 and DM water rinse (RC 4) B110.

Figure 2a illustrates a schematic front cross-section of a conventional self-triggering centrifugal oil separator 20 used in present system and having a water seal (S) provided about a hydro-hermetic outlet 1 showing the degreasing chemical DC contaminated with oil and other foreign particles (L) and gas (G) marked entering and flowing inside the oil separator 20 through a cylindrical inward passage 08 provided therein. The centrifugal oil separator 20 consists of an oil separator outer body 02, the 7.5 KW motor shaft 04 rotating continuously at 2800 rpm, a multi-plate passage 06, an inward path 08 for the contaminated degreasing chemical, a pressure gauge 10 to show the pressure deflection from the reference pressure Pref marked therein. The operating water (W) is shown in the lower part and unseparated liquid L in the central portion of the body 02.

Figure 2b shows the front cross-section of a conventional self-triggering centrifugal oil separator 20 with contaminated degreasing chemical DC starting to fill inside the portion provided with the multi-plate passage 06 of the oil separator 20 and rotating in a circular motion due to the rotating motor shaft 04. The pressure inside oil separator 20 starts increasing and is displayed on pressure gauge 10. The unseparated liquid (L) is getting collected in outer most cavity and the cleaned liquid (CL) peripherally accumulated within multi-plate passages 06.

Figure 2c shows the front cross-section of a conventional self-triggering centrifugal oil separator 20 with the heavier contaminated oil particles 12 or sludge (SL) start accumulating on the circumference of the oil separator 20 due to the centrifugal force developed by the rotating shaft 04 and separated clear chemical (CH) flows through the passage provided at the centre of the centrifugal separator 20.

Figure 2d shows the front cross-section of a conventional self-triggering centrifugal oil separator 20 with the heavier contaminated oil particles 12 or sludge (SL) accumulated on the circumference of the oil separator 20 and unseparated liquid (L) inward thereof due to the centrifugal force developed by the rotating shaft 04 and separated clear chemical (CH) flows through the passage provided at the centre of the centrifugal separator 20 and discharged through hydro-hermetic outlet 1 thereof.

Figures 2e shows the front cross-section of a conventional self-triggering centrifugal oil separator 20 in which on pressure reaching the maximum preset value, the heavier contaminated oil particles or sludge (SL) is discharged through the vent 16 provided in the oil separator 20. Now, to relieve the high-pressure inside the oil separator 20.

FIGURE 3 shows the front cross-section of a conventional self-triggering centrifugal oil separator 20 of Figures 2a-2e with the repetition of process steps of Fig. 2c to 2e and the situation inside the oil separator 20 after the discharge of the heavier contaminated oil particles 14 and sludge (SL) from the vent 16. Although, the heavier contaminated oil 14 or sludge (SL) is already separated from degrease chemical DC by this process, there are following major drawbacks of this process:

a) Centrifugal oil separator 20 is more sensitive to dirty liquid, so it attracts frequent sensor failures.

b) Dirt/mug still gets deposited in the multi-plate passages 06 and it gradually affects the performance of the oil separator 20.

Figure 4 shows a schematic diagram of the oil separator mechanism 200 configured in accordance with the present invention, which receives oil mixed degreasing chemical DC from the degrease tank. The oil separator mechanism includes the following main portions: an oil separator tank as the main tank 100 made of mild steel (MS) having several portions; i.e. an oil settling tray 116 for collecting separated oil 108 in the oil settling compartment 118; baffle plate arrangement 122 including baffle plates 102 specially designed, e.g. corrugated and made of oleophilic material having a tendency to attract oil and repel water. These plates 102 are inclined, preferably making an angle of 600 with respect to the horizontal surface and are installed mutually parallel in the direction of flow of chemical 104. The baffle plate arrangement 122 increases the surface contact time of the oil-mixed degreasing chemical DC flowing therethrough and reduces it velocity for separating oil from this chemical by starting the accumulation of oil on the plates 102 as bubbles 106 rising to the top of the baffle plate arrangement 122 and floating as large oil drops 108. While the separated dirt 110 strikes the corrugation of the baffle plates and starts falling downward due to heavy weight thereof and gets accumulated as dirt/muck 112 in the hopper 114 disposed below the oil separation tank 200. The oil drops 108 floating above the baffle plate arrangement 122 are collected in an oil collecting tray 116 provided in the oil settling compartment 118. The hopper 114 preferably has a truncated conoidal shape with tapered walls and equipped with a main tank drain valve 126, preferably a butterfly valve to drain out dirt/muck/sludge 112 at regular intervals during cleaning of the oil separation tank 200. It helps in removing cleaning water through the drain line (not shown). A vertical level balancer pipe 128 is fitted in the clear chemical compartment 130, preferably fitted from outside the bottom thereof. This vertical pipe 128 allows to adjust the level of chemical 132 flowing from the baffle plates arrangement 122 to the oil settling compartment 118 to help collection of the oil floating in the oil collection tray 116 having a drain line fitted with a ball valve (not shown) for controlling the flow of collected oil and to carry it to the main oil collection tank 140 (Figure 5).

Figure 5 shows an enlarged partial view of the oil separator mechanism 200 marked as encircled potion T in Figure 4. This portion includes a solenoid valve A (preferably an electro-pneumatic valve) fitted at the oil separator 200 inlet, which can be shut-off instantly on receiving a high-level signal from the float sensor C fitted in the clear chemical compartment 130. A clear chemical return pump, preferably a 7.5 kW pump 134 is also provided downstream the clear chemical compartment 130 for transferring separated clear chemical 132 to the dip-degrease tank 136 (not shown). This clear chemical pump 134 is operated intermittently (i.e. approx. 15 min/hour - 6 hours/day) depending on the level of the clear chemical 132 collected in the clear chemical compartment 130.

Accordingly, two float sensors, i.e. a clear chemical transfer pump on/off sensor B and a high-level alarm sensor C are installed in the clear liquid collection compartment 130. First floating clear chemical pump on/off sensor B issues a signal to start or stop the chemical transfer pump 134 for transferring or stopping this transfer of clear chemical collected in the clear chemical collection section 130 towards degrease chemical bath 136 (not shown).

In an abnormal condition, when the level of clear chemical 132 increases in the clear chemical collection compartment 130 to reach the maximum level thereof, the second floating high-level alarm sensor C issues a signal to the system to close the solenoid valve A fitted on the inlet of the oil separator mechanism 200 to avoid any overflow of the chemical.

Another floating oil high-level sensor D is fitted in the separated oil collection tank 140, and on reaching the maximum oil level therein due to any reason, this floating oil high-level sensor D also issues a signal to the system to close the solenoid valve A fitted on the inlet of oil separator mechanism 200.

WORKING OF THE INVENTION

The following process steps are undertaken in the oil separator mechanism 200, once the contaminated degrease chemical DC enters this improved oil separator 200:

(i) Degrease chemical DC flows due to gravity from the tank side-tray (not shown) to the oil separator 200 through solenoid valve A.

(ii) Degrease chemical DC entered in the oil separator 200 comes in contact with the inclined baffle plates 102 of the corrugated deflector plates 122 made of oleophilic material, e.g. a substance with affinity for oils and not for water.

(iii) Continuous contact of the oil mixed degrease chemical DC with the these oleophilic plates 102 gradually enlarges the size of the oil particulates forming bubbles 106 and making large-sized oil drops 108, which rise to the top of liquid surface.

(iv) Dirt particles/muck 110 present in the degrease chemical DC strike the inclined oleophilic plates 122 and move down to settle as dirt/muck 112 at the bottom of the hopper 124 which is also equipped with a butterfly valve 126 to drain out this dirt/sludge 112 at regular intervals and during cleaning of the oil separation tank 200, it also helps in removing cleaning water through the drain line (not shown).

(v) Clear chemical 132 flows straight in the direction 104 through the plates 122 towards the vertical pipe 128 and enters the pipe from bottom and collects in the clear chemical compartment 130.

(vi) Floating oil 108 accumulates on the liquid surface and the clear chemical 132 and overflows into first collecting tray 118.

(vii) Further, oil mixed chemical in first tray 118 is separated by metal baffles 120 and clear oil 108 passes to oil collection tray 116, from which separated oil 108 is taken out via another valve 130 to the final oil collection tank 140.

(viii) Clear chemical 132 passes below the oil collection tray 116 and collects in clear chemical compartment 130, from where it is pumped by a clear chemical pump 136 back to the dip-degrease tank 136.

TECHNICAL ADVANTAGES AND ECONOMIC SIGNIFICANCE

The system to separate oil from degrease chemical and configured in accordance with the present invention has the following technical and economic advantages:

• Reduces oil content in the degreasing bath from 4.00 to 2.5 gm/liter to substantially improve the process parameter.

• Reduces suspended dirt particles in the degreasing bath 2300 to 1500 ppm.

• Eliminates manual oil skimming activity, so spared manpower can be used for other maintenance activities.

• Saves electrical energy by up to 24000 units per annum.

• Saves LNG, which was required for boiler to heat chemical up to 80°C.

• Oil separator mechanism 200 developed in-house just @ a cost of INR 1.5 Lakh, thus saving capital expenditure of about INR 30 Lakh.

• Easy to operate and maintain.

• Lesser moving parts in the mechanism, thus saving cost of machines spares worth about INR 3.75 Lakh per annum.
• Oil separator mechanism 200 can be used both for Emulsifying and Non-Emulsifying chemicals.

• Oil separation in Emulsifying chemical is possible without any external energy such as heat or mechanical force.

• Maintenance free system as it operates on Fluid Mechanics.

• Less skill is required to operate system.

• No disadvantage like bowl disc choking as in the conventional centrifuge oil separator.
• Dirt can be removed through hopper and drain system.

• “Zero” energy consumption to separate oil from oil-degrease chemical mixture.

• Eliminates pre-filtration of chemical before sending to oil separator unit.

• Eliminates additional utilities like flushing water and Compressed air.

The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.

The description provided herein is purely by way of example and illustration. The various features and advantageous details are explained with reference to this non-limiting embodiment in the above description in accordance with the present invention.

The descriptions of well-known components and manufacturing and processing techniques are consciously omitted in this specification, so as not to unnecessarily obscure the specification.
It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, the skilled person will recognize that the embodiments herein can be practiced with modification within the spirit and scope of embodiments described herein.

Therefore, the skilled person can easily make innumerable changes, variations, modifications, alterations and/or integrations in terms of materials and method used to configure, manufacture and assemble various constituents, components, subassemblies, assemblies and in terms of the size, shapes, orientations and interrelationships without departing from the scope and spirit of the present invention.

The numerical values given of various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher or lower than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the disclosure unless there is a statement in the specification to the contrary.

Throughout this specification, the word “comprise”, or variations such as “comprises” or “comprising”, shall be understood to implies including a described element, integer or method step, or group of elements, integers or method steps, however, does not imply excluding any other element, integer or step, or group of elements, integers or method steps.

The use of the expression “a”, “at least” or “at least one” shall imply using one or more elements or ingredients or quantities, as used in the embodiment of the disclosure in order to achieve one or more of the intended objects or results of the present invention. ,CLAIMS:We claim:

1. A system (200) to separate oil from a contaminated mixture thereof with a degreasing chemical to be used for pre-treatment of vehicle bodies in paint-shops of automobile manufacturing plants, said system comprising:

• a multi-chamber oil separator tank (100) having an inlet (104) on one side thereof for supplying the mixture of dirty degreasing chemical and oil; and an outlet on the other side thereof, for removing the clean degreasing chemical;

• a baffle plate arrangement (122) having a plurality of baffle plates (102) disposed inside said tank (100);

• an oil settling tank (120) for collecting oil and degreasing chemical separated from dirt/muck/sludge present in said mixture;

• an oil collection tray (116) disposed in said tank (120);

• a clean degreasing chemical tank (130) with an outlet disposed at the other side of said oil separator tank (100); and

• an oil collection tank (140) for collecting oil separated from said mixture;

wherein said baffle plate arrangement (122) comprises a plurality of baffle plates disposed parallel to each other and inclined with respect to the horizontal plane for separating the oil, dirt and degreasing chemical present in said mixture in separate chambers of said multi-chamber oil separator tank (100).

2. System as claimed in claim 1, wherein said baffle plates are made of oleophilic material and configured with corrugations to attract oil and repel water, the inclination of said baffle plates increases the surface contact time of said mixture therewith and reduces the velocity of oil separating therefrom accumulating as separated oil bubbles floating to the top of said tank (100) and formed as large oil drops; the dirt striking said corrugations and dropping down as separated dirt (110) to the bottom of said tank (100); and the mixture of oil and degreasing chemical moving forward towards said oil collecting tank (110) for further separation into oil overflowing into said oil collection tray (116) and clean degreasing chemical (132) flowing into said clean chemical tank (130).
3. System as claimed in claim 1, wherein said multi-chamber oil separator tank (100) comprises a main tank (100) for installing said baffle plate arrangement (122); an oil settling compartment (120) having an oil collection tray disposed therein; and a clean degreasing chemical collection tank (130) with a vertical level balancer pipe (128) fitted at the bottom centre thereof and sharing a common wall with said oil settling tank (120).

4. System as claimed in claim 1, wherein said multi-chamber oil separator tank (100) comprises a hopper (114) disposed at the bottom thereof, preferably having a truncated conical shape; and equipped with drain valve (126), preferably a butterfly valve for draining out at regular intervals, the dirt/muck/sludge (112) separated from said mixture and collected at the bottom of said tank (100) during the cleaning of said oil separator tank (100).

5. System as claimed in claim 3, wherein said vertical level balancer pipe (128) is fitted in said clear chemical collection tank (130), preferably fitted from outside the bottom thereof; said vertical pipe (128) allowing to adjust the level of the clean degreasing chemical (132) flowing from said baffle plates arrangement (122) to said oil settling compartment (120) to help collection of the oil floating in said oil collection tray (116); and a clear chemical transfer pump fitted downstream thereof for transferring separated clean degreasing chemical (132) to a dip-degrease tank (136).

6. System as claimed in claim 5, wherein said oil collection tray (116) comprises a drain line fitted with a ball valve for controlling the collected oil flow and carrying said collected oil to said main oil collection tank (140).

7. System as claimed in claim 3, wherein said oil collection tank (120) comprises said oil settling compartment (120) with an inclined inflow side (118) disposed parallel to and level with said arrangement (122) and with a gap (126) therebetween for overflowing said dirt-free oil and chemical mixture into said oil collection tank (120); an oil guide (124) to lead oil from said mixture into said oil collection tray (116); and an outflow side of said tank (120) made common with the inflow side of said clean degreasing chemical collection tank (130).
8. System as claimed in claim 1, wherein the outlet of said multi-chamber oil separator tank (100) configured on the other side thereof is provided on the wall thereof common with said clean degreasing chemical collection tank (130).

9. System as claimed in anyone of the claims 1 to 8, wherein the inlet of said multi-chamber oil separator tank (100) comprises:

• a solenoid valve (A), preferably an electro-pneumatic valve fitted upstream the inlet thereof;

• first on/off float sensor (B) for said clear chemical transfer pump, and a second high-level alarm sensor (C) fitted in said clear degreasing chemical collection compartment (130); and

• a floating oil high-level sensor (D) fitted in said separated oil collection tank (140).

10. System as claimed in claim 1, wherein said multi-chamber oil separator main tank (100) is made of mild steel (MS) and comprises said baffle plate arrangement (122) with a plurality of baffle plates (102) disposed parallel to each other and inclined with respect to the horizontal plane, preferably making an angle of 600 for separating the dirt from the contaminated mixture of oil and degreasing chemical in separate chambers (116), (130), and (140) thereof.

11. A process for separating oil and dirt/muck/sludge from the mixture of oil and degreasing chemical by means of the system (200) as claimed in anyone of the claims 1 to 10, said method comprising the steps of:

• supplying the mixture of the contaminated degreasing chemical (DC) and oil by gravity from the tank side-tray to said oil separator tank (200) via solenoid valve (A);

• contacting said mixture with said inclined baffle plates (102) having affinity for oils and non-affinity for water;

• separating the oil particles from said mixture by gradual enlargement thereof by forming bubbles (106) to rise to the top of the liquid surface in said tank (100) as large oil drops (108);
• separating the dirt particles/muck/sludge (110) from said mixture by striking said inclined baffle plates (122) and dropping down said separated dirt/muck/sludge particles as settled muck/sludge (112) at the bottom of said hopper (124) and draining out thereof at regular intervals during cleaning of said oil separation tank (100);

• separating said clear degreasing chemical (132) by flowing through said baffle plates (102) and leading the same towards said vertical pipe (128) by entering through the bottom thereof and collecting said clear degreasing chemical in said clear chemical compartment (130);

• accumulating said floating mixture of separated oil drops (108) and degreasing chemical and overflowing said mixture into said oil settling compartment (120);

• separating oil from said mixture of by oil guide (124) as clear oil (108) by passing the same to said oil collection tray (116) for subsequent removal to said oil collection tank (140); and

• passing said clear degreasing chemical (132) from separated in said oil collection tray (116) for collection in said clear chemical compartment (130) for final pumping by means of a clear degreasing chemical pump to a dip-degrease tank (136).

Digitally Signed.

Dated: this day of 30th AUGUST 2017. SANJAY KESHARWANI
APPLICANT’S PATENT AGENT