Compact modular facility for preparing an explosive emulsion precursor

Abstract

The present invention relates to a modular facility (1) for producing an explosive emulsion precursor made up of a water-in-oil reverse emulsion, the facility comprising: - a first tank (2) for preparing an aqueous phase comprising a first heating means (3) and first stirring means for stirring the aqueous phase (4), the first tank being in communication with first pump circulation means (5) for circulating a) the aqueous phase directly or indirectly to a shearing device (6) for preparing the water-in-oil reverse emulsion, b) the feed water of the first tank from a water storage tank, and c) nitrate from a nitrate storage tank (7); - a second tank (8) for preparing an oil phase comprising a second heating means (9) and second stirring means for stirring the oil phase (10), the second tank being in communication with second pump circulation means (11) for circulating d) the oil phase from the second tank directly or indirectly to a shearing device (6) and e) components of the oil phase from external component storage tanks (12) to the second tank (8); - at least one third storage tank (13) for storing the emulsion in communication with the shearing device (6) via third pump circulation means (14) for circulating f) the water-in-oil reverse emulsion; - a heat-transfer fluid supply means (15) for supplying the first (3) and second (9) heating means with heat-transfer fluid, the facility being characterised in that the heat-transfer fluid supply means (15) is a hot water boiler and in that the first heating means (3) is a coil-shaped tubular heat exchanger made up of two tubes in a staggered arrangement.

Description

[0001] Title of the invention

[0002] Compact modular plant for the preparation of an explosive emulsion precursor

[0003] Technical field

[0004] The present invention relates to a compact modular plant for the preparation of an explosive emulsion precursor and to the use of the modular plant according to the invention for the production of an explosive emulsion precursor consisting of an inverse emulsion of water in oil.

[0005] Prior art

[0006] Explosives precursors are typically manufactured on-site by mixing an aqueous phase containing nitrates and constituting an oxidizer with an oil phase containing a surfactant and constituting a fuel. On-site mixing for the manufacture of explosives precursors helps limit transport risks.

[0007] The aqueous phase is generally prepared by dissolving ammonium nitrates and / or sodium nitrates and / or calcium nitrates in water with the addition of additives to promote carbonation and possibly additives to adjust the pH of the aqueous phase. In order to facilitate the dissolution of the nitrates, the weight proportion of which is around 80%, the water is heated to a temperature of at least 65°C, preferably to a temperature of at least 85°C.

[0008] The oily phase comprises a mixture of different vegetable and / or mineral fats and surfactants. The oily phase can, for example, be obtained by mixing new or recovered mineral oils, such as paraffin or fuel oils, with a quantity of surfactants in a proportion of 10 to 30% of the total oily phase. The oily phase is generally heated between 40 and 90 °C so as to reduce the temperature difference with the aqueous phase and promote their mixing. To obtain the emulsion constituting an explosive precursor, a low-viscosity premix or pre-emulsion is prepared in a tank using stirring means. The low viscosity of this pre-emulsion gives this pre-emulsion insufficient stability and consistency for the preparation of an explosive, which is why a shearing device is used to increase the viscosity of this pre-emulsion.The emulsion constituting the explosive precursor will subsequently be made explosive by adding and mixing chemical reagents such as sodium nitrite solution and / or solid sensitizing agents such as glass microspheres in on-site manufacturing units just before use as an explosive.

[0009] In order to limit the risks and take into account the specificity of the emulsion constituting the explosive precursor, it has been proposed in the prior art to prepare it on site using a transportable modular installation that can be assembled on site. To facilitate the transport of the various elements necessary for the preparation of the emulsion, these are transported in several containers that will be arranged on site. There are also modular installations comprising several containers that make it possible to avoid carrying out the various stages of preparation of the precursor of the emulsion within the same container.

[0010] However, the presence of numerous containers does not facilitate their transport, arrangement, or modularity of the installation. A large surface area is also required for this type of installation. In addition, these installations are intended for the preparation of large quantities of explosive emulsion precursors, in the order of 10,000 tons per year, and are therefore not suitable for the production of smaller quantities and at lower costs.

[0011] There is therefore a need to have a facility for the manufacture of an explosive emulsion precursor, which is of measured size, not very complex, easy to install, easy to dismantle and transport so as to be able to easily prepare, under safe conditions on or near the site of implementation of an explosive composition, an explosive emulsion precursor suitable for use in the preparation of an explosive composition. In particular, there is a need to have a modular facility whose implementation is simple, rapid, inexpensive, safe, and easy to implement for the preparation of small or moderate quantities of explosive emulsion precursor, for example of the order of 1500 to 2500 t / year.

[0012] In particular, there is a need to have a modular installation of measured size for the preparation of small quantities of explosive emulsion precursor so as to limit the preparation costs but also to be able to advantageously prepare on demand the necessary quantities of explosive emulsion precursor for the preparation of an explosive composition and thus promote the obtaining of an explosive composition having good pyrotechnic characteristics.

[0013] There is also a need to have a modular installation for the preparation of an explosive emulsion precursor that is simple, rapid, inexpensive, secure, and easy to implement on or near the site of implementation of an explosive composition.

[0014] To this end, the present invention advantageously provides an installation for the preparation of an explosive emulsion precursor, the elements composing it of which are advantageously capable of being combined within a single container, and a use of said installation for the preparation of an explosive emulsion precursor meeting the existing needs mentioned above.

[0015] The Applicant realized that it was possible to have a plant for the preparation of an explosive emulsion precursor, which is of measured size, not very complex, easy to install, dismantle and transport so as to be able to safely prepare on site, an explosive emulsion precursor and in particular in small to moderate quantities. The Applicant also realized that it was possible to use the modular plant according to the invention for the manufacture of an explosive emulsion precursor consisting of an inverse emulsion of water in oil, which is easy and inexpensive to implement, even for small to moderate quantities. Summary of the invention

[0016] Accordingly, a first object of the invention relates to a modular installation (1) for the manufacture of an explosive emulsion precursor consisting of an inverse emulsion of water in oil comprising:

[0017] - a first tank (2) for the preparation of an aqueous phase comprising a first heating means (3) and first means for stirring the aqueous phase (4), the first tank communicating with first pumping circulation means (5) of a) the aqueous phase directly or indirectly to a shearing device (6) for the preparation of the inverse emulsion of water, b) feed water to the first tank from a water storage tank, and c) nitrate from a nitrate storage tank

[0018] (7),

[0019] - a second tank (8) for preparing an oily phase comprising a second heating means (9) and second means for stirring the oily phase (10), said second tank communicating with second pumping circulation means (11) of d) the oily phase from the second tank directly or indirectly to a shearing device (6) and e) components of the oily phase from external component storage tanks (12) to the second tank

[0020] (8),

[0021] - at least a third emulsion storage tank (13) communicating with the shearing device (6) via third pumping circulation means (14) of f) the inverse water-in-oil emulsion

[0022] - a heat transfer fluid supply means (15) for supplying heat transfer fluid to the first (3) and second (9) heating means, said installation being characterized in that the heat transfer fluid supply means (15) is a hot water boiler and in that the first heating means (3) is a tubular heat exchanger of helical shape composed of two tubes arranged in a staggered pattern.

[0023] A second object of the invention relates to the use of the modular installation according to the first object of the invention for the manufacture of an explosive emulsion precursor consisting of an inverse emulsion of water in oil.

[0024] The use according to the invention advantageously makes it possible to easily manufacture, and at lower cost, small to moderate quantities of an explosive emulsion precursor consisting of an inverse emulsion of water in oil.

[0025] Brief description of the drawings

[0026] [Fig. 1] Figure 1 represents a perspective view of the installation according to the invention, in which we can see - a first tank (2) for the preparation of an aqueous phase comprising a first heating means (3) which is a tubular heat exchanger of helical shape composed of two tubes arranged in a staggered manner, first means for stirring the aqueous phase (4), the first tank communicating with first means for circulating by pumping (5) a) the aqueous phase directly or indirectly to a shearing device (6) for the preparation of the inverse emulsion of water, b) the feed water of the first tank from a water storage tank, and c) nitrate from a nitrate storage tank (7), - a second tank (8) for the preparation of an oily phase comprising a second heating means (9) and second means for stirring the oily phase (10),said second tank communicating with second pumping circulation means (11) of d) the oily phase from the second tank directly or indirectly to a shearing device (6) and e) components of the oily phase from external component storage tanks (12) to the second tank (8), - at least a third emulsion storage tank (13) communicating with the shearing device (6) via third pumping circulation means (14) of f) the inverse water-in-oil emulsion and - a heat transfer fluid supply means (15) which is a hot water boiler for supplying heat transfer fluid to the first (3) and second (9) heating means.,

[0027] [Fig. 2] Figure 2 represents a perspective view of the installation according to the invention comprising a fourth tank (16) for the preparation of a pre-emulsion composed of the mixture of the aqueous phase and the oily phase, said tank comprising third stirring means (17) and communicating with the first tank (2) via the first pumping circulation means (5), with the second tank (8) via the second pumping circulation means (11) and with the shearing device (6) via fourth pumping circulation means of the pre-emulsion (18).

[0028] [Fig. 3] Figure 3 represents the installation according to the invention in which several elements are included in the same container (A).

[0029] [Fig. 4] Figure 4 represents the first tank (2) comprising a first heating means, which is a tubular heat exchanger of helical shape composed of two tubes arranged in a staggered pattern.

[0030] Detailed description of the invention

[0031] The present invention relates to a modular installation (1) for the manufacture of an explosive emulsion precursor consisting of an inverse emulsion of water in oil comprising:

[0032] - a first tank (2) for the preparation of an aqueous phase comprising a first heating means (3) and first means for stirring the aqueous phase (4), the first tank communicating with first pumping means (5) for circulating a) the aqueous phase directly or indirectly to a shearing device (6) for the preparation of the inverse emulsion of water, b) feed water to the first tank from a water storage tank, and c) nitrate from a nitrate storage tank (7), - a second tank (8) for the preparation of an oily phase comprising a second heating means (9) and second means for stirring the oily phase (10),said second tank communicating with second pumping circulation means (11) of d) the oily phase from the second tank directly or indirectly to a shearing device (6) and e) components of the oily phase from external component storage tanks (12) to the second tank (8),

[0033] - at least a third emulsion storage tank (13) communicating with the shearing device (6) via third pumping circulation means (14) of f) the inverse water-in-oil emulsion

[0034] - a heat transfer fluid supply means (15) for supplying heat transfer fluid to the first (3) and second (9) heating means, said installation being characterized in that the heat transfer fluid supply means (15) is a hot water boiler and in that the first heating means (3) is a tubular heat exchanger of helical shape composed of two tubes arranged in a staggered pattern.

[0035] The present application therefore proposes a modular installation for the manufacture of an explosive emulsion precursor consisting of an inverse emulsion of water in oil, the volume and size of the elements which compose it of which is greatly reduced compared to that of existing installations. For the purposes of the invention, a modular installation is understood to mean an installation comprising several elements which can be linked to each other.

[0036] The modular installation according to the invention is easy to transport, to arrange and has a small footprint, particularly on the ground, due to the reduced number of tanks, while offering safe implementation conditions for the preparation of an explosive emulsion precursor.

[0037] The reduced size of the installation due to a limited number and volume of tanks makes it possible to reduce the installation time but also the cost of transport and installation of this installation.

[0038] The number and limited volume of the tanks included in the installation according to the invention make it possible to arrange all or part of the elements making up the installation, preferably all, in a single container. The possibility of arranging all or part of the elements making up the installation in a single container makes it easier to transport the installation, to facilitate its installation and to limit the floor space taken up.

[0039] Having a modular installation for the manufacture of an explosive emulsion precursor, the components of which are of reduced volume and size, also makes it possible to easily produce small to moderate quantities of explosive emulsion precursor, while controlling production costs. The present invention proposes in an original manner the implementation of a hot water boiler as a means of supplying heat transfer fluid. This characteristic advantageously makes it possible to overcome the regulatory constraints linked to the use of a means of supplying heat transfer fluid requiring pressurization, such as a steam boiler, which can be complex depending on the country.Using a hot water boiler as a means of supplying heat transfer fluid also reduces the costs of preparing the explosive emulsion precursor given the lower temperature of the heat transfer fluid compared to a steam boiler. Using hot water as a heat transfer fluid also limits the risks associated with high temperature and / or pressure, as well as the potential risks of environmental pollution that could be expected with another type of heat transfer fluid.

[0040] In the context of the invention, nitrates are understood to mean ammonium nitrates, and / or sodium nitrates and / or calcium nitrates, or a mixture of these salts, preferably ammonium nitrate.

[0041] For the purposes of the invention, the term "pre-emulsion" means the mixture which can be formed by mixing the aqueous phase and the oily phase in a fourth tank using stirring means but whose low viscosity provides insufficient stability and consistency for the preparation of an explosive emulsion precursor.

[0042] In the context of the present invention, the aqueous phase is typically prepared by dissolving ammonium, and / or sodium and / or calcium nitrates in water to which additives promoting carbonation and possibly additives for adjusting the pH of the aqueous phase are added. Due to the high concentration of nitrates (in a weight proportion of approximately 80-82% to 18-20% water) and in order to facilitate their dissolution, the water is heated to a temperature of at least 65°C (degrees Celsius), preferably to a temperature of 85°C.

[0043] In the context of the present invention, the components of the oily phase are various vegetable and / or mineral fatty substances and surfactants. The oily phase can be obtained by mixing new or recovered mineral oils such as paraffinic oils and fuel oil, preferably in a weight proportion of 50 / 50 to 80 / 20 with a quantity of surfactants in a proportion of 10 to 30% by weight relative to the total weight of the oily phase.

[0044] To promote mixing and reduce the temperature difference between the aqueous phase and the oil phase before mixing them in the third tank, the oil phase is heated to approximately 40-90°C, preferably 50-70°C.

[0045] The modular installation according to the invention allows the manufacture of an explosive emulsion precursor consisting of an inverse emulsion of water in oil according to the following main steps: a) a step of preparing an aqueous phase by dissolving the nitrate in water while heating, b) a step of preparing an oily phase by mixing components comprising at least one vegetable and / or mineral fatty substance and a surfactant while heating, c) a step of preparing an inverse emulsion of water in oil using a shearing device. According to a particular embodiment, step c) may be preceded by a step of preparing a pre-emulsion by mixing the aqueous phase with the oily phase.

[0046] The installation according to the present invention also comprises means for circulating fluid by pumping water to supply water to the hot water boiler from a water storage tank and means for circulating fluid by pumping fuel oil to supply fuel oil to the hot water boiler from a fuel oil storage tank.

[0047] In the context of the present invention, the term tubular heat exchanger means a tubular device for transferring thermal energy by conduction from one fluid to another without mixing them. The heat flow passes through the exchange surface which separates the fluids.

[0048] According to a particular aspect of the modular installation, the second heating means (9) is a tubular heat exchanger of helical shape.

[0049] In a particular embodiment of the invention, the second heating means is a tubular heat exchanger composed of two helical tubes arranged in a staggered pattern.

[0050] The particular geometry of the helical-shaped tubular heat exchangers present in the first and possibly in the second tank advantageously facilitates heat exchanges with the aqueous phase and the oily phase respectively.

[0051] In particular, the implementation of a tubular heat exchanger of helical shape composed of two helical tubes arranged in a staggered pattern as the first means of heating the first tank is particularly advantageous because it makes it possible to improve the heat exchanges between the aqueous phase and the heat transfer fluid included in said tubular thermal element and therefore to heat the aqueous phase more easily, more quickly, homogeneously and at lower costs. These advantageous effects are made possible in particular thanks to the particular geometry of the heat exchanger, in particular the staggered arrangement of the two helical tubes which compose it and which allows improved contact of the aqueous phase with the heat transfer fluid. In addition, this staggered geometry advantageously promotes the agitation of the aqueous phase in a turbulent regime on the exchanger, which promotes the heat exchange between the heat transfer fluid and said aqueous phase.

[0052] The tubular heat exchanger of the first tank allows for easy heating of small to moderate quantities of aqueous phase. Advantageously, the tubular heat exchanger of the first tank allows for rapid and easy heating of the aqueous phase to a temperature of at least 65°C (degrees Celsius), preferably at least 70°C and more preferably to a temperature of 85°C.

[0053] The second heating means of the modular installation and in particular the helical tubular heat exchanger of the second tank, make it possible to heat the oil phase to a temperature between 40 and 90°C, preferably between 50 and 60°C (degrees Celsius).

[0054] Generally speaking, the modular installation according to the invention advantageously makes it possible to easily and quickly heat small to moderate quantities of aqueous phase and / or oily phase thanks to the presence of the hot water boiler as a means of supplying heat transfer fluid and the presence of a tubular heat exchanger of helical shape composed of two tubes arranged in a staggered pattern.

[0055] The particular geometry of the heat exchanger advantageously makes it possible to use a hot water boiler as a means of supplying heat transfer fluid instead of a steam boiler and therefore to overcome the disadvantages associated with it, while ensuring sufficient heating of the aqueous phase and / or the oily phase.

[0056] The tubular heat exchanger of the first tank may have a length of between 30 and 100 meters, preferably between 70 and 80 meters, and a diameter of between 30 and 100 mm, preferably between 40 and 70 mm.

[0057] The second heating means of the modular installation and preferably the helical tubular heat exchanger, may have a length of between 30 and 100 meters, preferably between 70 and 80 meters and a diameter of between 30 and 100 mm, preferably between 40 and 70 mm.

[0058] In the context of the present invention, the first and second stirring means are respectively contained in the first and second tanks. These first and second stirring means respectively allow the aqueous phase and the oily phase to be stirred and therefore promote heat exchanges with the helical-shaped tubular heat exchangers and therefore facilitate the heating of the aqueous phase and the oily phase. The first stirring means advantageously allow the heat to be better distributed within the first tank and promote the homogeneous dissolution of the nitrate granules in the tank.

[0059] In the context of the present invention, the stirring means comprise at least one vertical rod extending inside the tank in which they are included and on which are mounted rotating stirring blades capable of being actuated in rotation around a vertical axis using a motor.

[0060] In the context of the present invention, the nitrate storage tank comprises a hopper connected to a metering screw for conveying the nitrate to the first tank. The installation according to the present invention may comprise one or more third emulsion storage tanks, preferably it comprises two emulsion storage tanks.

[0061] In the context of the invention, the means for circulating fluid by pumping correspond to fluid transfer pipes associated with pumps equipped with mass flow meters. These may be, for example, progressive cavity dosing pumps driven by an electric geared motor.

[0062] According to a particular aspect of the invention, the first (3) and the second heating means (9) are arranged at the level of all or part of the internal periphery of the walls of respectively the first tank (2) and the second tank (8).

[0063] The term “internal periphery of the walls” of the first and second tanks respectively means the internal zone of said tanks located near the internal surface of the walls, preferably located at a distance of between 8 and 30 cm, more preferably between 11 and 18 cm from the internal surface of the walls of the tanks.

[0064] By "all or part of the internal periphery" of the walls of said tanks, it is meant within the meaning of the present invention that the first and second heating means are arranged over at least 50%, preferably at least 60%, more preferably at least 80%, of the height of the internal periphery of the wall of the first tank and / or the second tank.

[0065] According to a particular aspect of the invention, the first heating means (3) is arranged over at least 50% of the height of the internal periphery of the wall of the first tank (2).

[0066] Preferably, the first heating means is arranged over at least 80% of the height of the internal periphery of the wall of the first tank.

[0067] According to a further particular aspect of the invention, the second heating means and preferably the helical tubular heat exchanger is arranged over at least 80% of the height of the internal periphery of the wall of the second tank.

[0068] The installation according to the present invention also comprises a water storage tank intended to supply the boiler and the first tank, a nitrate storage tank, a storage tank for each of the components of the oily phase, said components being a vegetable and / or mineral fatty substance, preferably mineral, and a surfactant, a fuel oil storage tank to supply energy to the hot water boiler.

[0069] According to an advantageous embodiment of the installation according to the invention, all or part of the tanks are cylindrical in shape.

[0070] The modular installation according to the invention therefore has the advantage of being compact. Due to this compactness, the elements making up the installation are brought together within a single container, or possibly two containers. Having a single container, or possibly two containers, advantageously makes it possible to easily transport the modular installation. Thus, according to a particular aspect, the invention relates to a modular installation in which:

[0071] - the first tank (2) for the preparation of the aqueous phase,

[0072] - the first (3) and second (9) heating means,

[0073] - the first (4) and second (10) means of agitation,

[0074] - the first (5), second (11) and third (14) means of circulation by pumping,

[0075] - the second tank (8) for the preparation of the oily phase,

[0076] - the shearing device (6) and

[0077] - the hot water boiler (15), are included in a first container (A).

[0078] More specifically, the first container (A) contains:

[0079] - the first tank (2) for the preparation of the aqueous phase,

[0080] - the first (3) and second (9) heating means,

[0081] - the first (4) and second (10) means of agitation,

[0082] - the first (5), second (11) and third (14) means of circulation by pumping,

[0083] - the second tank (8) for the preparation of the oily phase,

[0084] - the shearing device (6) and

[0085] - the hot water boiler (15), of the modular installation according to the invention.

[0086] In a particularly preferred embodiment, the first container (A) does not contain energy supply means corresponding to a generator set and / or an air compressor.

[0087] According to a particularly preferred aspect, the invention relates to a modular installation in which:

[0088] - the first tank (2) for the preparation of the aqueous phase,

[0089] - the first (3) and second (9) heating means,

[0090] - the first (4) and second (10) means of agitation,

[0091] - the first (5), second (11) and third (14) means of circulation by pumping,

[0092] - the second tank (8) for the preparation of the oily phase,

[0093] - the shearing device (6) and

[0094] - the hot water boiler (15), are contained only in a single container (A). The shearing device makes it possible to increase in a controlled manner the viscosity of the composition or mixture comprising the aqueous phase and the oily phase so as to obtain an explosive emulsion precursor. Preferably, the shearing device makes it possible to obtain an explosive emulsion precursor having a viscosity setpoint value of between 10,000 and 35,000 cps (centipoise). This viscosity value can be measured with a viscometer, for example a tabletop analog viscometer.

[0095] The shearing device of the modular installation according to the invention is arranged upstream of the third emulsion storage tank. In the installation according to the invention, the shearing device communicates with the third storage tank via the third emulsion pumping circulation means.

[0096] According to a particular embodiment, the modular installation according to the invention comprises a fourth tank (16) for the preparation of a pre-emulsion composed of the mixture of the aqueous phase and the oily phase, said tank comprising third stirring means (17) and communicating with the first tank (2) via the first pumping circulation means (5), with the second tank (8) via the second pumping circulation means (11) and with the shearing device (6) via fourth pumping circulation means of the pre-emulsion (18).

[0097] In this embodiment the fourth tank is arranged upstream of the shearing device.

[0098] The third stirring means for preparing the emulsion comprise means capable of mixing the aqueous phase and the oily phase so as to form a composition called a “pre-emulsion”. The third stirring means may comprise at least one vertical rod extending inside the third tank, on which are mounted rotating stirring blades capable of being actuated in rotation around a vertical axis using a motor. The shearing device makes it possible to increase in a controlled manner the viscosity of the “pre-emulsion” before its transfer in the form of an explosive emulsion precursor to the third storage tank via the third circulation means by pumping the emulsion.

[0099] According to a particular aspect of this embodiment, the fourth tank (16), the third stirring means (17) and the fourth pumping circulation means (18) of the pre-emulsion are included in the first container (A).

[0100] According to another embodiment, the modular installation according to the invention is devoid of a fourth tank for the preparation of a pre-emulsion. In this embodiment, the first and second tanks communicate directly with the shearing device respectively via first and second pumping circulation means. In this embodiment, the shearing device may be a dynamic mixer.

[0101] This embodiment is particularly advantageous because it makes it possible to improve the fineness of the emulsion and thus increase the shelf life of the physicochemical properties of said emulsion. The installation according to the invention may comprise an electrical cabinet for controlling the electrical power supply of the entire installation, said cabinet preferably being arranged in the first container (A).

[0102] According to a preferred aspect of the invention, the modular installation according to the invention also comprises a control panel capable of controlling the various means of circulating fluid by pumping, the various stirring means, and the various heating means. The control panel advantageously provides all the elements necessary for controlling the preparation of the emulsion precursor. The control panel also allows various valves and flow meters present in the modular installation to be controlled. The control panel also allows the electrical cabinet to be controlled, enabling the power supply of the entire installation to be controlled.

[0103] According to a particular aspect, the installation according to the invention comprises means for supplying electrical energy to supply electricity to at least the pumping circulation means (5, 11, 14, 18) and the stirring means (4, 10, 17).

[0104] In the context of the present invention, the means for supplying electrical energy comprise a generator set and / or an air compressor.

[0105] In one embodiment, the modular installation comprises a second container (B) in which at least the means for supplying electrical energy corresponding to a generator set and / or an air compressor are arranged.

[0106] In another particularly preferred embodiment, the modular installation comprises only the first container (A). In other words, in this embodiment the modular installation is devoid of a second container. In this embodiment, the means for supplying electrical energy corresponding to a generator set and an air compressor are provided directly on site.

[0107] The compressor makes it possible in particular to supply air to the various pneumatic pumps forming part of the installation according to the invention.

[0108] The control panel can be placed in the first container (A), in the second container (B) or outside these containers.

[0109] In a particular embodiment, the installation comprises a first container comprising:

[0110] - the first tank for the preparation of the aqueous phase,

[0111] - the first and second means of heating,

[0112] - the first, second and when present the third, means of agitation,

[0113] - the first, second and third means of fluid circulation by pumping, - the second tank for the preparation of the oily phase,

[0114] - the hot water boiler

[0115] - when present, the third tank for the preparation of a pre-emulsion and a second container (B) comprising at least the energy supply means.

[0116] The first container (A) and / or the second container (B) present in the installation according to the invention are provided with at least one door on at least one of their transverse walls. These doors allow in particular the entry and exit of the different elements making up the modular installation but also the passage of operators for the installation, commissioning or maintenance of the different elements making up the modular installation according to the invention.

[0117] In particular, the modular installation according to the invention is devoid of a buffer tank intended to temporarily collect the emulsion f) before its storage in at least a third storage tank (13).

[0118] The absence of a buffer tank to temporarily collect the explosive emulsion precursor advantageously makes it possible to reduce the size of the modular installation and thus make it more compact.

[0119] More particularly, the third tank for storing (13) the emulsion f) is provided with means for collecting said emulsion.

[0120] This arrangement advantageously allows samples of the explosive emulsion precursor to be taken directly from the storage tank and provides a modular installation for the manufacture of a more compact explosive emulsion precursor.

[0121] The means for sampling the explosive emulsion precursor are advantageously arranged at a closable opening of the storage tank, preferably at the opening through which the explosive emulsion precursor is intended to enter, so as to be able to carry out a sampling and / or an analysis of the explosive emulsion precursor automatically or semi-automatically upstream of its storage in said tank.

[0122] According to a preferred aspect of the invention, the sampling and / or analysis of the explosive emulsion precursor is carried out automatically or semi-automatically thanks to the presence of analysis laboratory furniture and equipment and a control panel capable of controlling the means for sampling the explosive emulsion precursor. These elements can be arranged in the second container (B) of the invention or in a third container (C).

[0123] The various tanks of the modular installation can be supported by load cells which advantageously make it possible to precisely determine and control the quantity of the aqueous phase, the oily phase, the possible pre-emulsion and the precursor of the explosive emulsion. In the context of the invention, the various tanks of the modular installation comprise one or more closable openings intended for the passage of people, in particular for maintenance operations.

[0124] According to a particular aspect of the invention, the first (2), second (8), third (13) and fourth (16) tanks comprise closable openings through which fluid transfer pipes are connected between said tanks and / or electrical cables.

[0125] The fact that the openings are closable makes it easier to transport these tanks, full or empty.

[0126] The fluid transfer pipes and / or the electrical cables consist of cable portions or pipe portions having at their ends connection elements which can be connected and disconnected to complementary sockets present at the level of said walls of one or more of the closable openings present on different tanks of the modular installation.

[0127] Advantageously, the fluid transfer pipes and / or the electrical cables consist of cable portions or pipe portions capable of being fixed via connection plugs present at other connection elements and / or at one or more closable openings. The connection plugs allow rapid connections and disconnections of the different cable portions and / or pipe portions.

[0128] Within the scope of the invention, the fluid transfer lines comprise:

[0129] - a transfer line for the aqueous phase from the first tank directly to the shearing device or to the fourth tank for preparing a pre-emulsion

[0130] - a heat transfer fluid transfer line between the heat transfer fluid supply means and the heating means of the first tank, and

[0131] - an oil phase transfer line, from the second tank directly to the shearing device or to the fourth tank for preparing a pre-emulsion

[0132] - a heat transfer fluid transfer line between the heat transfer fluid supply means and the heating means of the second tank, and

[0133] - a transfer line for the pre-emulsion from the fourth tank when present to the shearing device

[0134] - a transfer line for the emulsion from the shearing device to the third emulsion storage tank, and

[0135] - supply lines to the second tank with components of the oily phase, in particular vegetable and / or mineral fats and surfactants, from external storage tanks.

[0136] Within the framework of the invention, the modular installation also comprises different pumping groups comprising: - a pump for supplying water to the first tank from a water storage tank,

[0137] - a pump for circulating the aqueous phase from the first tank to the shearing device or to the fourth tank for preparing a pre-emulsion

[0138] - pumps for supplying components of the oil phase from external storage tanks to the second tank,

[0139] - a pump for circulating the oil phase from the second tank directly to the shearing device or to the fourth tank for preparing a pre-emulsion

[0140] - a pre-emulsion circulation pump from the fourth tank when present to the shearing device

[0141] - a pump for discharging the emulsion from the shearing device to the emulsion storage tank.

[0142] In particular, the modular installation according to the invention is characterized in that:

[0143] - the first tank (2) comprises at least a) an opening through which passes a portion of the aqueous phase transfer pipe from the first tank (2) directly or indirectly to the shearing device (6), a portion of the heat transfer fluid transfer pipe between the heat transfer fluid supply means (15) and the first heating means (3), and a portion of the water supply pipe to the first tank (2) from a water storage tank (19) and b) an opening through which passes a portion of the nitrate transfer pipe from a nitrate storage tank (7)

[0144] - the second tank (8) comprises at least one opening through which passes a portion of the oil phase transfer pipe from the second tank (8) directly or indirectly to the shearing device (6), a portion of the heat transfer fluid transfer pipe between the heat transfer fluid supply means (15) and the second heating means (9), and portions of the oil phase component supply pipe from external storage tanks (12)

[0145] - the third storage tank comprises at least one opening through which passes a portion of the emulsion transfer pipe f) from the shearing device (6).

[0146] Preferably, one or more of the tanks of the installation, preferably each of said tanks, comprises a manhole for maintenance of the tanks.

[0147] In the context of the invention, the components of the oily phase comprise a vegetable and / or mineral fatty body and a surfactant, preferably said components comprise oil, fuel oil and a surfactant.

[0148] According to a particular aspect, the installation according to the invention comprises a transfer pipe for conveying the components of the oily phase from storage tanks of each of the components to the second tank, using a pump cooperating with connection valves to which are connected supply pipes for each of the components from the storage tanks. In particular, the installation according to the invention comprises a transfer pipe for conveying the emulsion using a pump cooperating with a valve, from the shearing device to the third emulsion storage tank.

[0149] In particular, the installation according to the invention comprises a water transfer pipe from the hot water boiler to supply a pipe connected to an upper orifice of the first heating means via a valve and of the second heating means via a valve.

[0150] The modular installation according to the invention has the advantage of being able to be easily modulated thanks to the addition of optional additional equipment, such as a cooling tower, which can be easily connected to the installation via connection plugs present at the connection elements and / or at one or more closable openings.

[0151] According to one embodiment of the invention, the installation comprises a fifth tank comprising a cooling module for the explosive emulsion precursor, which may comprise a cooling tower associated with a plate exchanger. In this embodiment, the fifth tank is connected to the shearing device via a fluid transfer pipe and connection plugs present at connection elements and / or at one or more closable openings.

[0152] A second object of the invention relates to the use of the modular installation according to the invention for the manufacture of an explosive emulsion precursor consisting of an inverse emulsion of water in oil.

[0153] All of the definitions and particular and preferred characteristics stated above for the first subject of the invention, namely the modular installation, apply mutatis mutandis to the second subject of the invention, namely the use of the modular installation according to the invention.

[0154] In particular, the use according to the invention comprises: a) a step of preparing an aqueous phase by dissolving the nitrate in water while heating, b) a step of preparing an oily phase by mixing components comprising at least one vegetable and / or mineral fatty substance and a surfactant while heating, c) a step of preparing an inverse emulsion of water in oil in which the aqueous phase and the oily phase are, directly or in the form of a pre-emulsion, subjected to shearing.

[0155] Step a) is carried out in a first tank. In the context of the present invention, step a) is carried out by dissolving ammonium, and / or sodium and / or calcium nitrates or a mixture of these salts, preferably ammonium nitrate, in water. The dissolution may be followed by the addition of additives promoting the and possibly additives making it possible to adjust the pH of the aqueous phase. According to a particularly preferred aspect, the nitrates are added in a weight proportion of approximately 80-82% for 18-20% of water. Step a) is carried out at a temperature of at least 65°C (degrees Celsius), preferably at a temperature between 60 and 100°C, which advantageously facilitates the dissolution of the nitrates in the water.

[0156] Step b) is carried out in a second tank. In the context of the present invention, step b) is carried out by mixing a vegetable and / or mineral fatty substance such as paraffinic oils and fuel oil, preferably in a weight proportion of 50 / 50 to 80 / 20 with a quantity of surfactant in a proportion of 10 to 30% by weight relative to the total weight of the oily phase. Step b) is carried out at a temperature between 40 and 90°C, preferably between 50 and 60°C (degrees Celsius). This temperature makes it possible to reduce the temperature difference with the aqueous phase and to facilitate their mixing.

[0157] The shearing of step c) may be carried out using a shearing device, which may be a static or dynamic mixer. The shearing makes it possible to increase in a controlled manner the viscosity of the composition comprising the aqueous phase and the oily phase or of a pre-emulsion obtained from the aqueous phase and the oily phase, and to obtain an explosive emulsion precursor.

[0158] In a first embodiment of step c), the aqueous phase and the oily phase are directly transferred via fluid transfer lines from the first and second tanks respectively to a shearing device. In this embodiment, the shearing device may be a dynamic mixer.

[0159] In a second embodiment of step c), the aqueous phase and the oily phase are transferred in the form of a pre-emulsion via fluid transfer lines from a fourth pre-emulsion preparation tank to a shearing device.

[0160] In this embodiment, step c) therefore comprises two successive sub-steps:

[0161] - a first sub-step in which the aqueous phase and the oily phase are mixed using stirring means so as to form a first mixture called “pre-emulsion” and

[0162] - a second sub-step in which the pre-emulsion is subjected to shearing using a shearing device so as to obtain an explosive emulsion precursor consisting of an inverse emulsion of water in oil.

[0163] In the first sub-step, the stirring means may comprise at least one vertical rod on which are mounted rotating stirring blades capable of being actuated in rotation around a vertical axis using a motor.

[0164] In this embodiment, the shearing device may be a static mixer.

[0165] Step c) of the use according to the invention makes it possible to obtain an explosive emulsion precursor having a viscosity setpoint value of between 10,000 and 35,000 cps (centipoise). For step c), 80 to 90%, preferably 90% of aqueous phase and approximately 10 to 20%, preferably 10% of oily phase by weight relative to the total weight of the explosive emulsion precursor are directly subjected to shearing or mixed to obtain a pre-emulsion before being subjected to shearing.

[0166] According to a preferred embodiment, step c) is followed by a step d) in which the emulsion formed in step c) is stored in a third storage tank. Step d) may be followed or preceded by a step of cooling the emulsion formed in step c).

[0167] Example 1: Qualification tests of the means of supplying the heat transfer fluid to heat the aqueous phase

[0168] A) Materials and methods

[0169] The means of supplying the heat transfer fluid is a hot water boiler in the installation according to the invention, unlike the installations of the prior art which use water vapor boilers.

[0170] In this test, the characteristics of the heating system including the hot water boiler and the helical-shaped tubular heat exchanger composed of two tubes arranged in a staggered pattern are as follows:

[0171] [Table 1]

[0172] The following steps were taken:

[0173] 1. Fill a tank with 2400 L of water

[0174] 2. Heat the hot water boiler

[0175] 3. Open the hot water network in the heat exchanger and record the heating time from an initial temperature Ti to a final temperature Tf in the aqueous phase tank. 4. Record the following parameters during heating: tank temperature, flow rate, inlet / outlet temperature, pressure, boiler temperature).

[0176] The test conditions are as follows:

[0177] -Volume of water in the tank: 2400 L

[0178] - Initial temperature of the water in the tank: 11.5°C

[0179] - Initial temperature of the water in the boiler: 6°C

[0180] - Outside temperature: 9°C

[0181] - Tank agitation in operation

[0182] B) Results

[0183] It takes 20 minutes for the boiler water to reach a temperature of 98°C and it takes 1h3 minutes for the aqueous phase to reach a temperature of 90°C.

[0184] It is found that it is possible to heat the aqueous phase efficiently and quickly to the desired temperature by using a hot water boiler as a means of supplying a heat transfer fluid in combination with a helical-shaped tubular heat exchanger composed of two tubes arranged in a staggered pattern as the primary heating means.

[0185] Example 2: Monitoring of different parameters during the manufacture of the aqueous phase

[0186] This test illustrates the monitoring of different parameters during the manufacture of the aqueous phase.

[0187] 1) Materials and methods

[0188] The different parameters monitored are:

[0189] - Temperature of the aqueous phase

[0190] - Nitrate screw flow rate

[0191] - Heat exchanger inlet - outlet temperatures

[0192] - Hot water flow in the heat exchanger

[0193] - Hot water network pressure

[0194] The following steps were taken:

[0195] 1. Filling the tank with the quantity of water appropriate for the recipe then 2. Starting the boiler and heating the water in the tank

[0196] 3. When the water reaches the set temperature of 85°C, start the screw and add the nitrate

[0197] 4. End of heating when all the nitrate has been introduced and the temperature of the tank for the preparation of the aqueous phase reaches 90°C.

[0198] The test conditions are as follows:

[0199] - Volume of water in the tank: 500 L

[0200] - Dense ammonium nitrate: 3000 kg

[0201] - Initial temperature of the water in the tank = 34°C

[0202] - Initial temperature of the water in the boiler = 13°C

[0203] - Outside temperature = 5°C

[0204] - Tank agitation in operation

[0205] 2) Results

[0206] The results of the test are as follows:

[0207] It takes 20 minutes for the boiler water to reach a temperature of 98°C and it takes 18 minutes to heat the tank water from 34°C to 85°C since the first circulation means were started.

[0208] It takes 2 hours and 48 minutes to heat the aqueous phase tank to 90°C from the addition of nitrates for a nitrate flow rate of 12 to 20 kg / min.

[0209] It takes 3 hours 6 minutes total time to heat the tank for the preparation of the aqueous phase and the dissolution of the nitrates.

[0210] The total time is 3hl2min for the preparation of the aqueous phase.

[0211] It is found that it is possible to prepare the aqueous phase efficiently and quickly by using a hot water boiler as a means of supplying a heat transfer fluid in combination with a helical-shaped tubular heat exchanger composed of two tubes arranged in a staggered pattern as the primary heating means.

Claims

Demands 1. Modular installation (1) for the manufacture of an explosive emulsion precursor consisting of a reverse water-in-oil emulsion comprising: - a first tank (2) for the preparation of an aqueous phase comprising a first heating means (3) and first means for stirring the aqueous phase (4), the first tank communicating with first means for circulating by pumping (5) a) the aqueous phase directly or indirectly to a shearing device (6) for the preparation of the reverse water emulsion, b) feed water to the first tank from a water storage tank, and c) nitrate from a nitrate storage tank (7), - a second tank (8) for the preparation of an oily phase comprising a second heating means (9) and second means for stirring the oily phase (10), said second tank communicating with second means for pumping circulation (11) of d) the oily phase from the second tank directly or indirectly to a shearing device (6) and e) components of the oily phase from external component storage tanks (12) to the second tank (8), - at least one third storage tank (13) for the emulsion communicating with the shearing device (6) via third pumping circulation means (14) of f) the reverse water-in-oil emulsion - a means of supplying heat transfer fluid (15) to supply heat transfer fluid to the first (3) and second (9) heating means said installation being characterized in that the means of supplying heat transfer fluid (15) is a hot water boiler and in that the first heating means (3) is a tubular heat exchanger of helical shape composed of two tubes arranged in a staggered pattern.

2. Modular installation according to claim 1 in which the second heating means (9) is a tubular heat exchanger of helical shape.

3. Modular installation according to claim 1 or 2 in which the first (3) and the second heating means (9) are arranged at the level of all or part of the inner periphery of the walls of the first tank (2) and the second tank (8), respectively. Modular installation according to any one of the preceding claims, wherein the first heating means (3) is disposed over at least 50% of the height of the inner periphery of the wall of the first tank (2). Modular installation according to any one of the preceding claims, wherein: - the first tank (2) for the preparation of the aqueous phase, - the first (3) and second (9) means of heating, - the first (4) and second (10) means of agitation, - the first (5), second (11) and third (14) means of circulation by pumping, - the second tank (8) for the preparation of the oily phase, - the shearing device (6) and - the hot water boiler (15), are included in a first container (A). Modular installation according to any one of the preceding claims characterized in that it comprises a fourth tank (16) for the preparation of a pre-emulsion composed of a mixture of the aqueous phase and the oily phase, said tank comprising third stirring means (17) and communicating with the first tank (2) via first pumping circulation means (5), with the second tank (8) via second pumping circulation means (11), and with the shearing device (6) via fourth pumping circulation means for the pre-emulsion (18). Modular installation according to claims 5 and 6 in which the fourth tank (16), the third stirring means (17), and the fourth pumping circulation means (18) for the pre-emulsion are included in the first container (A).A modular installation according to any one of the preceding claims, characterized in that it comprises means for supplying electrical power to supply electricity to at least the pumping circulation means (5, 11, 14, 18) and the stirring means (4, 10, 17). A modular installation according to any one of the preceding claims, characterized in that it lacks a buffer tank for temporarily collecting the emulsion (f) before its storage in at least a third storage tank (13). A modular installation according to any one of the preceding claims, characterized in that the third storage tank (13) for the emulsion (f) is provided with means for withdrawing said emulsion.

11. Modular installation according to any one of the preceding claims characterized in that the first (2), second (8), third (13) and fourth (16) tanks comprise closable openings through which fluid transfer lines between said tanks and / or electrical cables are connected.

12. Modular installation according to any one of the preceding claims, characterized in that: - the first tank (2) includes at least a) an opening through which passes a portion of the aqueous phase transfer line from the first tank (2) directly or indirectly to the shearing device (6), a portion of the heat transfer fluid line between the heat transfer fluid supply means (15) and the first heating means (3), and a portion of the water supply line to the first tank (2) from a water storage tank (19) and b) an opening through which passes a portion of the nitrate transfer line from a nitrate storage tank (7) - the second tank (8) includes at least one opening through which passes a portion of the oil phase transfer line from the second tank (8) directly or indirectly to the shearing device (6), a portion of the heat transfer fluid line between the heat transfer fluid supply means (15) and the second heating means (9), and portions of the oil phase component supply line from external storage tanks (12) - the third storage tank includes at least one opening through which passes a portion of the emulsion transfer line f) from the shearing device (6).

13. Use of the modular installation according to any one of claims 1 to 12 for the manufacture of an explosive emulsion precursor consisting of a reverse water-in-oil emulsion.

14. Use according to claim 13 comprising: a) a step of preparing an aqueous phase by dissolving the nitrate in water by heating, b) a step of preparing an oily phase by mixing components comprising at least one vegetable and / or mineral fat and a surfactant by heating, c) a step of preparing an inverse water-in-oil emulsion in which the aqueous phase and the oily phase are, directly or in the form of a pre-emulsion, subjected to shear.

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