Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
  • B63B25/00—Load-accommodating arrangements, e.g. stowing, trimming; Vessels characterised thereby
  • B63B25/02—Load-accommodating arrangements, e.g. stowing, trimming; Vessels characterised thereby for bulk goods
  • B63B25/08—Load-accommodating arrangements, e.g. stowing, trimming; Vessels characterised thereby for bulk goods fluid
  • B63B25/10—Load-accommodating arrangements, e.g. stowing, trimming; Vessels characterised thereby for bulk goods fluid open to ambient air
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B08—CLEANING
  • B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
  • B08B9/00—Cleaning hollow articles by methods or apparatus specially adapted thereto 
  • B08B9/08—Cleaning containers, e.g. tanks
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
  • B65D90/00—Component parts, details or accessories for large containers
  • B65D90/22—Safety features
  • B65D90/38—Means for reducing the vapour space or for reducing the formation of vapour within containers
  • B65D90/44—Means for reducing the vapour space or for reducing the formation of vapour within containers by use of inert gas for filling space above liquid or between contents

Definitions

• the invention relates to an installation for making non-flammable and non-explosive permanently a flammable and explosive liquid when it is contained in a reser ⁇ see.
• the volume of the tank not occupied by the liquid is filled with a mixture of air and vapor in a percentage which varies according to the nature of the liquid, the ambient temperature and that of the liquid, the pressure which prevails in the volume. unoccupied tank, depending on whether it is open, closed, closed and pressurized. If the liquid contained in the tank consists of a mixture, the majority of the compounds in the vapor will be the compounds of the mixture which are the most volatile, ie those which are generally the most flammable.
• REPLACEMENT SHEET representing a danger to the entire environment of the reservoir. To avoid this, several techniques have been developed.
• flame retardant is considered to be an action to make it non-flammable and non-explosive and the term flame retardant means an agent intended to make it non-flammable and non-explosive.
• fireproofing can be achieved in several ways: either by ensuring that the volume of the unoccupied reservoir of liquid is oversaturated with vapor and therefore beyond the upper flammability limit, by means of devices various which cause, for example, the air to bubble through the liquid when the tank is sampled, or by making so that the atmosphere inside the tank also contains a percentage of substance not suitable for combustion such as as nitrogen, exhaust gases from internal combustion engines, carbon dioxide, or substances with high extinction characteristics such as halogen gases for example, in which cases these substances are used in a percentage of the order of 10% to 20%, depending on the volume occupied in the tank by steam.
• These fireproofing operations are also made necessary when it is necessary to intervene for operations of handling and repairing of the tanks, to avoid the danger that certain accidental causes may cause disastrous explosions.
• the washing operation requires fireproofing of the tank beforehand, to avoid any danger and to make the interior of the tank accessible to operators under safe conditions.
• the present invention aims to provide a permanent fireproofing installation which not only has all the performance provided by the most advanced fireproofing systems currently known, but also provides other advantages, in particular that of guaranteeing protection against environment surrounding the tank in the event of rupture of the latter, sufficient to avoid explosions in the first moments of the spill outside the liquid contained, and in most cases, to also avoid fire .
• An improved form of this installation also has the advantage of allowing the tank having contained the combustible liquid to be washed.
• the subject of the invention is an installation according to claim 1.
• the installation as shown in FIG. 1 comprises a tank 1 containing the liquid fuel to be protected by flame retardancy, a container 2 containing the flame retardant, a pump 3 intended for transferring the flame retardant agent from the container 2 to the zone situated above the liquid ' of the reservoir 1, by passing it through a unidirectional solenoid valve 4 and through gasifiers 5, by means of a supply line 6 and a valve 29.
• An inlet pipe 9 allows the introduction of the combustible liquid into the tank 1, by means of a valve 10. In this way, only the liquid which comes to supply the tank 1 at a pressure higher than that existing in tank 1 can enter the latter.
• a purification device 13 comprising a series of baffle separators and filters, is used to separate the impurities and the fraction of the combustible liquid which has condensed in this compression phase, from the flame retardant, so that only l the pure and liquid flame retardant is introduced into the container 2.
• the products other than the flame retardant are recovered via the line 14.
• a 'pressure gauge 15 controls, by a known automatic mechanism, the operation of the compressor 12 and the pump 3, so as to maintain in the tank 1 an atmosphere of flame-retardant gas at a pressure previously fixed.
• the value of this limit pressure is chosen as a function of thermodynamic considerations, the nature of the combustible liquid and the flame retardant chosen, as well as the amplitude of the thermal variations to which the tank is subjected. This pressure will be called "operating pressure".
• a reservoir 16 of compressed nitrogen is provided which, by means of a pressure reducer 17, keeps inside the container 2 containing the flame retardant. , a pressure such that it causes, during a stop of operation of the pump 3, an influx of flame retardant agent into the tank 1, by means of an additional line 18 and a non-return valve 19, which guarantees the presence of flame retardant gas in the tank 1 at a pressure close to the "working pressure".
• a non-return valve 20 then prevents the flame-retardant agent from reaching the purification device 13 and the pipe 11.
• the injectors 28 are arranged to inject the washing agent in the liquid state on the walls of the tank 1 and on its upper part, with sufficient energy supplied by the pump 3, in a manner which guarantee
• the deposits which have become much more fluid thanks to the solvent properties of the washing liquid, are discharged into a bottom discharge 21 through a valve 22 in a retention tank 23 which includes a heating element 24 allowing the washing liquid to evaporate. .
• These vapors of the washing liquid are brought, by means of a pipe 25 provided with a non-return valve 26, to the compressor 12 which will liquefy said vapors, thus allowing their purification by means of a purification device 13 comprising a group of baffle separators and filters. This makes it possible to recover almost entirely the washing liquid used.
• the other products are recovered via line 14.
• the washing cycle is determined from time to time depending on the nature of the liquid which was contained in the reservoir 1; The amount of washing liquid introduced into the tank 1 and the time of this introduction will vary depending on the consistency of the deposits. By providing two or more washing cycles depending on the case, it will be possible to achieve complete cleanliness of the reservoir 1, and storage of the deposits in the retention tank 23.
• the container 2 for the storage of the flame retardant and washing agent is preferably a tank capable of withstanding the pressure.
• the tank 1 and the container 2 are preferably part of the load-bearing structures of a ship.
• the transfer of the flame retardant and washing substance is carried out by means of a single pumping means 3, switchable by means of a valve (29), in order to be able to carry out the two functions of fireproofing and washing as desired.
• suction of the evaporating flame retardant and washing gases, and of compression of these gases is carried out by means of a single suction and compression means 13, co mutable by means of a valve provided to optionally provide the two fireproofing and washing functions.
• the separation of impurities from the flame retardant and washing agent is carried out by means of a single purification unit 13.
• the installation could be provided only to make the flammable and explosive liquid contained in a tank non-flammable and non-explosive.
• this variant would only include the parts shown in Figure 1.
• Another advantage of this installation is that, since the atmosphere of the tank consists of an inert and flame-retardant gas, the air never enters the tank 1 and the problems of corrosion by oxidation of the walls of the tank are reduced .
• the tank 1 described is a load tank of a tank vessel intended for the transport of flammable liquids such as crude oil, for example, in which case, washing can be done during navigation. , during the return journey between the port of destination of the crude oil and the port of loading.
• Another advantage of this installation is that the quantity of flame retardant and washing agent does not vary, unless an inevitable loss occurs. It therefore constitutes a fixed load which does not influence the stability of the means on which the installation is arranged.
• Another advantage of this installation is that it makes it possible to have a flame retardant agent tank with a compression pump and pipes, which can be used, under emergency conditions, for purposes other than those for which they were expected.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Ocean & Marine Engineering (AREA)
• Filling Or Discharging Of Gas Storage Vessels (AREA)
• Cleaning By Liquid Or Steam (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=4247822

Family Applications (1)

Country Status (7)

Families Citing this family (5)

Family Cites Families (6)

• 1991
  • 1991-10-18 CH CH306491A patent/CH685240A5/fr not_active IP Right Cessation
• 1992
  • 1992-10-16 WO PCT/NL1992/000185 patent/WO1993008103A1/fr active IP Right Grant
  • 1992-10-16 KR KR1019940701271A patent/KR100229701B1/ko not_active IP Right Cessation
  • 1992-10-16 JP JP5507620A patent/JPH07503924A/ja active Pending
  • 1992-10-16 AU AU29291/92A patent/AU2929192A/en not_active Abandoned
  • 1992-10-16 DE DE69202155T patent/DE69202155D1/de not_active Expired - Lifetime
  • 1992-10-16 EP EP92923399A patent/EP0607358B1/de not_active Expired - Lifetime

Non-Patent Citations (1)

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