Title of Invention

A SYSTEM TO PREVENT THE FORMATION AND ESCAPE OF VAPOURS OF HIGHLY INFLAMMABLE LIQUIDS FROM STORAGE TANKS

Abstract

A system for inhibiting the escaping of vapours of highly inflammable liquids from storage tanks comprises an underground storage tank (UST) for receiving and storing said liquids; an over board tank(OBT)() each of the said UST (1) and OBT (10) being provided with a single and/or interconnected plurality of flexible bladder(s) (3) and (12), the said bladders suspended in the air space volume (2) and (11) of UST and OBT, the said bladder secured in the vapour space to a connecting means (7) extending in vapour space of both UST and OBT by mounting means (6) and (9); inlet and outlet pipe(16) means for filling and emptying said UST.

Full Text

1524/MUM/2006 FORM 2 THE PATENTS ACT-1970 (39 of 1970) & The Patent Rules, 2006 COMPLETE SPECIFICATION (See Section 10 and Rule 13) 1. TITLE OF THE INVENTION A system to prevent the formation and escape of vapours of highly inflammable liquids from storage tanks 2. APPLICANT a) Name b) Nationality c) Address Shekhar Laxman Kulkarni, Age 52 years An Indian National 720/8, Navi Peth, Lai Bahadur Shastri Road, Pune-411030, Maharashtra India 3. PREAMBLE TO THE DESCRIPTION The following specification particularly describes the invention and the manner in which it is to be preformed 14-08-2007/25-03-2008 ORIGINAL 1524/MUM/2006 GRANTED FIELD OF INVENTION The present invention relates to a system to prevent formation and escape of vapours of highly inflammable liquids from storage tanks. More particularly it relates to a system that prevents formation and escape of vapours of highly inflammable liquids such as petroleum products viz. petrol, gasoline, or such other volatile solvents like alcohols, acetone etc. The present invention prevents escape of vapours from storage tank during decantation of such inflammable liquids from mobile tankers to the storage tanks or removing these liquids from the storage tanks during their reuse such as refilling of automobiles tanks etc. Still more particularly it relates to the said system provided for preventing escape of the vapours of inflammable liquids wherein underground/onboard storage tanks are used. BACKGROUND OF THE INVENTION Transportation of gasoline or highly inflammable liquids, with very low boiling point, like organic solvents is generally done through tankers which transport these liquids from the place of manufacturing or storage to the actual user points. The transportation of gasoline products particularly petrol as is generally and commonly known, is done using mobile tankers. The tankers are decanted into the storage tanks, underground/onboard, at the actual place of use or distribution such as petrol pumps. During such decantation considerable amount of vapours escape from the vents of the underground storage tanks (UST). In tropical countries, the variation in atmospheric temperatures is extreme. This variation between maximum and minimum temperatures may be up to 30 °C. The transfer of petrol is done mostly in daytimes wherein the temperature may range between 20 to 40 °C 2 throughout the year except in winter season. About 10, 000 litres of petrol is decanted to the UST in about 80-90 minutes. This operation which is done at high temperature results in heavy loss of petrol vapours to the atmosphere. Higher the temperature at the decantation, higher is the loss of vapours. It is estimated that the vapour loss.is to the tune of 0.4% at each transfer. Refuelling losses also contribute to VOC concentrations in ambient air. Considering the adverse impacts of VOCs on human health, climate and ecosystem, need of vapour recovery system at refueling units is evident. The vapour recovery system will help in reducing the ambient concentrations of Total volatile organic compounds (TVOCs) in air and as well save the gasoline of the order of three Giga grams per year at two cities Delhi and Mumbai. (only) Volatile Organic Compounds (VOCs) are important air pollutants in urban atmosphere. Some of the VOCs are toxic, potentially carcinogenic and mutagenic at concentrations levels found in urban environment {Edgerton et. al., 1989). Exposure to VOCs is of concern as it may result in significant risk to human health. Evaporative emissions of VOCs from gasoline distribution network are also one of the important sources of VOCs in ambient air. The problem of escape of the vapours to the atmosphere is severe during the transfer of the petrol from the tankers to UST or during fuelling of the automobiles wherein the petrol is transferred to the vehicles from the UST. This is also true in respect of transfer of the inflammable solvents from mobile tankers to UST or transfer for use from UST to place of use of such solvents in the industrial processes. As these transfers are done at a very high speed (approximately 5000/per 20-40 min) the loss of vapours is also 3 very high. During decantation of petrol from mobile tankers also the mixture of petrol vapours and air is displaced in atmosphere from the UST vents causing loss of the costly petrol and adding polluting VOCs in the atmosphere. The problem of loss of petrol vapours is tackled in Western countries using vehicles provided with "onboard refueling vapour recovery (ORVR) system or dispenser nozzles typicaJJy equipped witn vapour recovery systems. However such systems recover only partial petrol vapour - air mixture during refueling. The Healy 800 nozzle for Healy system used in western countries reduces the volume of air returned to the UST to approximately 25% of the liquid volume dispensed to an ORVR equipped vehicle. This causes problems in the busy service stations as ORVR refueling can cause the vapour pressure in the UST to drop to level below the set value at which the UST relief vent will open causing inflow of air into UST. The US patent No. 6,805,172, teaches a vapour space pressure control system for underground gasoline storage tanks. The said method and the system controls the pressure in the ullage vapour space of a volatile liquid fuel underground storage tank temporarily, during periods of increasing ullage vapour space pressure, allows vapour to flow into an auxiliary vapour space of variable volume, defined at least in part by a resilient wall member, thereby to rescue the volume of vapour otherwise released to the environment. The said passive pressure control system comprises of a tank containing a bladder. The said tank is provided a vent pipe having a pressure/vacuum relief valve set to ingest air into the ullage vapour space in response to the vapour space vacuum at -8 inch Water column (W.C.) and to 4 release the vapour from ullage space in response to the vapour pressure over +3 inches W.C. The storage tank is provided with a thin wall urethane bladder defining an auxiliary vapour space volume in communication with the underground storage tank vapour space and also defines an air space in communication with atmosphere through an air relief valve set to open at +3/4 inch W.C. to release air from the air space or at -3/4 inch W.C. to ingest air into the air space of the UST. The passive pressure control method provided by the said patent works well during refueling of with ORVR fitted motor vehicles and where the petrol distribution stations are provided with Healy 88 nozzles. In India, at present, these systems are not mandatory at the petrol pumps. The vehicles also are not at all provided with ORVR facilities. Hence there is a need to develop a system which will work well in conditions prevailing in the developing countries worldwide. The prior art system contains mixture of inflammable petrol and air. This being explosive there is always a danger of explosion. The system provided by the present invention has no such drawback and hence the hazards due to explosion are minimized. Objective of the invention The object of the present invention is to provide a system to prevent the formation and escape of vapours of highly inflammable liquids from storage tanks. Another object is to provide a system to prevent the formation and escape of vapours of highly inflammable liquids such as petroleum products like petrol, gasoline, or such other volatile solvents like alcohols, acetone during transfer 5 of such liquids from the mobile tankers to the underground storage tanks or vice-versa. Another object is to provide a system which can be installed with necessary modifications tothe existing system at a very low cost. SUMMARY OF INVENTION The present invention accordingly provides a system of tackling the problem of escaping of the petrol vapours to atmosphere, more particularly during the unloading of the petrol or volatile liquids from the mobile tanks to the UST tanks. The system provided by the present invention practically eliminates the possibility of escape of the vapours or its mixture in atmosphere. The system provided by the present invention comprises UST having single or plurality of bladders suspended in the air space volume of the said UST. When the UST is empty, these bladder(s) are in inflated condition because of air inside these bladders. The inflated bladders afford very little volume for vapour formation in the air space of the UGT and thus substantially prevents formation of vapours during the decantation of the inflammable liquid to UGT from the mobile tankers. The system for preventing the escaping of vapours of highly inflammable liquids from storage tanks comprising an underground storage tank (UST) and a over board tank (OBT), both the tanks provided with single or plurality of flexible bladders suspended inside these tanks, the said bladders held with these tanks with mechanical supports. Both the bladders in UST and the over board vapour tank (OBT) are connected with each other through connecting means. Both the tanks are also provided with conventional vapour escape outlets to the atmosphere. 6 In the present system only air is present in the bladders and therefore there is no possibility of explosion due to mixture of petrol vapour and air. STATEMENT OF THE INVENTION: A system for inhibiting the escaping of vapours of highly inflammable liquids from storage tanks comprises an underground storage tank (UST) for receiving and storing said liquids; an over board tank(OBT)() each of the said UST (1) and OBT (10) being provided with a single and/or interconnected plurality of flexible bladder(s) (3) and (12), the said bladders being suspended in the air space volume (2) and (11) of UST and OBT, the said bladder being secured in the vapour space to a connecting means (7) extending in vapour space of both UST and OBT by mounting means (6) and (9);inlet and outlet pipe(16) means for filling and emptying said UST . A system as claimed in claim (1) wherein the flexible single and/or plurality of bladders (3) and (12) in the UST and OBT respectively are connected to each other by a connecting means (7) such as a pipe, passing through the airtight flange(s) of UST and OBT, A system as claimed in claim (1) wherein the said connecting means (7) is provided with a safety pressure or a vacuum valve (8). A system as claimed in claim (1) wherein the UST is provided with a liquid dispensing or a pumping mechanism (20) through a nozzle (19). A system as claimed in claim (1) wherein the singular or plurality of bladder(s) in the UST and OBT is/are thin walled urethane bladder. 7 A system as claimed in claim (1) wherein the said singular or plurality of bladder(s)(3) and (12) are adaptably mounted on a connecting means (7) extending in both the UST and OBT using mounting means (9) and (6). A method of preventing escaping of vapours of highly inflammable liquids comprising the steps of : decanting the inflammable liquid to the UST from the mobile tanker, wherein the air displaced from the vapour space of the UST due to filling of the liquid passes into and accommodated the bladders in the OBT through connecting means (7) effecting the said bladder(s) in the OBT to inflate to accommodate the increase in air space volume of the said UST without any loss of vapours., UST comprises single or plurality of bladders suspended in the air space volume of the said UST, when the UST is empty these bladders are in inflated condition because of air inside these bladders, the inflated bladder afford very little volume for vapour formation in the air space of the UST. BRIEF DESCRIPTION OF THE DRAWING Figure 1 is a diagrammatic representation of the side sectional view of the present invention giving the positions of the bladder(s) (3) while decanting and refueling of the UST and corresponding changes in the bladder(s) (12) of OBT. The liquid levels (22) and (23) indicate the levels of the UST, when empty and after decanting from mobile tankers respectively. 8 DETAILED DESCRIPTION OF THE INVENTION According to Fig. (1) the system for inhibiting the escaping of vapours of highly inflammable liquids from storage tanks comprises an underground storage tank (UST) (1) defining a storage air space volume (2) for storage of volatile liquid fuel with an ullage vapour space provided with a manhole and an inlet for volatile liquid, an over board tank (OBT) (10) having air space volume (11) provided with a manhole (21) and (18) respectively, each of the said UST (1) and OBT (10) being provided with a single and/or interconnected plurality of flexible bladder(s) (3) and (12) respectively, the said bladders suspended in the air space volume (2) and (11) of UST and OBT, the said single bladder secured in the vapour space to a connecting means (7) extending in vapour space of both UST and OBT by mounting means (6) and (9) the said connecting means (7) being provided with a safety valve (8) at the OBT end. The UST (1) is provided with an opening (16), which acts as an inlet and outlet. The said opening (16) connected to the said UST by said connecting means (4) and (5). The flexible single and/or plurality of bladders (3) and (12) in the UST and OBT respectively are connected to each other by a connecting means (7) such as a pipe, passing through the airtight flange(s) of UST and OBT, In still another embodiment the said connecting means (7) is provided with a safety pressure or a vacuum valve (8). The UST provided with a liquid dispensing or a pumping mechanism (20) through a nozzle (19). 9 The singular or plurality of bladder(s) in the UST and OBT is/are thin walled urethane bladder. In another embodiment the said singular or plurality of bladder(s)(3) and (12) are adaptably mounted on a connecting means (7) extending in both the UST and OBT using mounting means (9) and (6). A system as described herein is used for preventing and escaping the fuel vapours from the. storage tanks of the automobiles with mechanical modification such as providing an additional tank similar to OBT with connecting means (7), mounting means and bladders. A method of preventing escaping of vapours of highly inflammable liquids comprising the steps of: decanting the inflammable liquid to the UST from the mobile tanker, wherein the air displaced from the vapour space of the UST due to filling of the liquid passes into and accommodated the bladders in the OBT through connecting means (7) effecting the said bladder(s) in the OBT to inflate to accommodate the increase in air space volume of the said UST without any loss of vapours., UST comprises single or plurality of bladders suspended in the air space volume of the said UST; when the UST is empty these bladders are in inflated condition because of air inside these bladders, the inflated bladder afford very little volume for vapour formation in the air space of the UST. In one of the features of the present invention the UST and OBT are secured to ground or support by concrete foundations (14). In another feature of the present invention the system provided by the present invention could be installed after retrograde modifications of the 10 existing UST, suitably adapting the available facilities to provide the OBT and the bladders after necessary mechanical modifications. In yet another feature of the present invention the UST (1) is provided with a safety valve (17). In another embodiment the OBT (10) is provided with an opening (13). Whenever petrol or highly inflammable liquid is decanted to the UST (1) from the mobile tanker, the sir space volume of the UST (1) is Filled by the decanted liquid resulting in building pressure due to formation of mixture of vapours of liquid and air, thereby displacing the air in the bladder(s) (3) of the UST (1), the displaced air from the bladder(s) is carried to the bladder(s) (12) of OBT (10) through connecting means (7), and the said bladder(s) (12) inflate(s) to absorb mixture of the petrol vapour and air. This creates the equilibrium of pressure in the UST (1) and OBT (10) and escape of vapours of petrol/inflammable liquid from UST (1) to atmosphere is prevented. In an embodiment of the pressure equilibrium system provided by the present invention comprises means for temporarily during the increased ullage vapour pressure reduction in the bladder(s) (2) volume causing corresponding increase in the volume of the bladder(s) (12) of the OBT triggering inflation of the said bladder(s) to equalize the pressure and during refilling of the automobiles, means for temporarily during the decreased ullage vapour pressure, inflation of the UST bladder(s) (2) causing corresponding decrease in the volume of the bladder(s) (12) in the OBT triggering deflation of the said bladder to equalize the pressure. When petrol or highly inflammable liquid is siphoned out of the UST (1) for refueling the automobiles or use in the industry, the vapour pressure in the 11 UST (1) drops and is vacuum created by the siphoning the petrol/inflammable liquid. This vacuum is created in the UST (1) causing bladder (3) to inflate, triggering transfer of corresponding volume of air from the bladder (12) to bladder (3) of UST (1) to bring the said bladder (3) to its original volume very slowly in a period of about 24 hours Thus the system provided by the present invention provides pressure equilibrium by inflation and deflation of bladder (3) and bladder (12). As these bladders are connected to each other, there is no loss of vapours to the atmosphere. In a feature of the present invention the pressure equilibrium system provided by the present invention may be associated with other conventional safety and vent means. ADVANTAGES OF THE PRESENT INVENTION 1. The present invention provides a closed pressure equilibrium system using two tanks, provided with flexible bladders connected to each other and therefore there is no escape of petrol vapours to the atmosphere. 2. The present system does not need electricity to control the escape of the vapours to atmosphere. 3. The cost of equipment and installation of this system is negligible as compared to the savings which are achieved by the closed system. 4. The installation of this system can be done on any existing storage tankers with little modifications. 5. The installation can be done very fast. 6. The system does not need any additional- equipment like vacuum pump which saves further consumption of energy. 12 7. The system provided by the present invention has considerable advantages over a conventional system with vertical tanks provided with variable roofs. The present systems with horizontal tanks are provided with pipe fittings and hence cannot have variable roofs as present in the vertical tanks. 13 I Claim: 1. A system for inhibiting the escaping of vapours of highly inflammable liquids from storage tanks comprises an underground storage tank (UST) for receiving and storing said liquids; an over board tank(OBT)() each of the said UST (1) and OBT (10) being provided with a single and/or interconnected plurality of flexible bladder(s) (3) and (12), the said bladders suspended in the air space volume (2) and (11) of UST and OBT, the said bladder secured in the vapour space to a connecting means (7) extending in vapour space of both UST and OBT by mounting means (6) and (9); inlet and outlet pipe(16) means for filling and emptying said UST. 2. A system as claimed in claim (1) wherein the flexible single and/or plurality of bladders (3) and (12) in the UST and OBT respectively connected to each other by a connecting means (7) such as a pipe, passing through the airtight flange(s) of UST and OBT, 3. A system as claimed in claim (1) wherein the said connecting means (7) provided with a safety pressure or a vacuum valve (8). 4. A system as claimed in claim (1) wherein the UST provided with a liquid dispensing or a pumping mechanism (20) through a nozzle (19). 5. A system as claimed in claim (1) wherein the singular or plurality of bladder(s) in the UST and OBT is/are thin walled urethane bladder. 6. A system as claimed in claim (1) wherein the said singular or plurality of bladder(s)(3) and (12) adaptably mounted on a connecting means (7) extending in both the UST and OBT using mounting means (9) and (6). 14 7. A method of preventing escaping of vapours of highly inflammable liquids comprising the steps of: decanting the inflammable liquid to the UST from the mobile tanker, wherein the air displaced from the vapour space of the UST due to filling of the liquid passes into and accommodated the bladders in the OBT through connecting means (7) effecting the said bladder(s) in the OBT to inflate to accommodate the increase in air space volume of the said UST without any loss of vapours, UST comprises single or plurality of bladders suspended in the air space volume of the said UST; when the UST is empty these bladders in inflated condition - of air inside these bladders, the inflated bladder afford very little volume for vapour formation in the air space of the UST. Dated this 25/09/2006

Documents:

1524-mum-2006-abstract(14-08-2007).pdf

1524-mum-2006-abstract.doc

1524-mum-2006-abstract.pdf

1524-mum-2006-cancelled pages(14-08-2007).pdf

1524-mum-2006-claims(granted)(25-03-2008).doc

1524-mum-2006-claims(granted)-(14-08-2007).pdf

1524-mum-2006-claims.doc

1524-mum-2006-claims.pdf

1524-mum-2006-correspondence(25-03-2008).pdf

1524-MUM-2006-CORRESPONDENCE(26-2-2010).pdf

1524-mum-2006-correspondence-ipo(28-03-2008).pdf

1524-mum-2006-correspondence-received.pdf

1524-mum-2006-description (complete).pdf

1524-mum-2006-drawing(14-08-2007).pdf

1524-mum-2006-drawings.pdf

1524-mum-2006-form 1(14-08-2007).pdf

1524-MUM-2006-FORM 15(26-2-2010).pdf

1524-mum-2006-form 2(granted)(25-03-2008).doc

1524-mum-2006-form 2(granted)-(14-08-2007).pdf

1524-mum-2006-form 9(09-10-2006).pdf

1524-mum-2006-form-1.pdf

1524-mum-2006-form-2.doc

1524-mum-2006-form-2.pdf

1524-mum-2006-form-9.pdf

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