FR3008989A1 - SYSTEM AND METHOD FOR TRANSFERRING SOLID MATERIAL IN GRANULAR FORM - Google Patents

Abstract

A transfer system (10) of solid material (11) in granular form, of a first chamber (E1) in which there is a first pressure (P1) towards a second chamber (E2) in which a second pressure (P2) prevails greater than the first pressure (P1), comprises a transfer lock (12) between the first and second enclosures (E1, E2) and delimiting an internal volume (V), an inlet opening (13) able to put into communication fluidic the internal volume (V) with the first chamber (E1), an exhaust opening (14) adapted to put in fluid communication the internal volume (V) with the second chamber (E2), a single piston (15) displaceable within the transfer lock (12) between first and second positions such that the internal volume (V) varies between a first value occupied in the first position of the piston (15) and a second value occupied in the second position of the piston (15) and lower than the first value, and a control element (16) of displacement of the piston (15) allowing the passage of the first value to the second value is performed by the piston (15) when the internal volume (V) is in fluid communication with the second chamber (E2) and before a fluidic communication connection between the internal volume (V) and the first chamber (E1) and that the passage of the second value to the first value is achieved by the piston (15) when the volume internal (V) is in fluid communication with the first enclosure (E1).

Description

FIELD OF THE INVENTION The invention relates to the field of solid material transfer in granular form, especially biomass, between two chambers in which different pressures prevail. The invention more particularly relates to a system and a method of transfer. It also relates to a preferred application of the method to the transfer of biomass to a gasification reactor. State of the art In the context of the invention, the term "granular" preferably refers to the fact that the solid material to be transferred is in the form of particles or grains, of variable or non-variable granulometry and of submillimetric, millimetric or centimeter dimensions, and which may be more or less mixed with a liquid. What is referred to as "biomass" includes under one of its uses any inhomogeneous material of biological origin, which can be quasi-dry, such as sawmill residues or straw, or soaked with water like household waste. Variable grain size, transport is problematic. However, in view of the valorisation of biomass which is more and more current or even imposed, such as for example by thermochemical conversion, the transport of this solid material is becoming widespread and must meet demanding criteria, such as the no losses, under optimal cost conditions. The solid particles of biomass are powders or chips, for example cellulosic particles, such as fine chips of plants, such as wood.

Many solid material transport or conveying systems exist, including those relating to biomass: conveyors, typically auger systems, pneumatic transfer systems or rotary sluice systems. But all these systems have been developed to operate at pressures near atmospheric pressure, or in other words for small pressure differences between the zones upstream and downstream of the conveying or transfer.

However, during the upgrading process, such as thermochemical conversion, it is necessary, from biomass of different types and sizes, usually stored at atmospheric pressure, to be able to continuously feed a reactor (gasification reactor), reactor type fluidized bed or a driven flow reactor operating under pressure. Generally the transfer of granular solid materials between a storage silo at atmospheric pressure and a downstream device operating at a higher pressure is carried out by a transfer system called "lock snap" using one or more intermediate pressurized transfer chambers, with nitrogen for example, or airlock. The pressurization makes it possible to go from the atmospheric pressure to the pressure of the downstream device which is, for example, a gasification reactor. This device is generally used for the gasification of coal and is composed of at least one transfer chamber (or at least one airlock), an upstream valve for the introduction of a volume of solid particles at atmospheric pressure and a downstream valve for the discharge in the feed chamber of the downstream device considered (chemical reactor) operating under high pressure.

The operation of the "lock-catch" type transfer system is cyclic, each cycle being summarized in the following steps: introduction of a volume of solid particles into the transfer chamber, most often by gravity, by opening the valve in upstream, the downstream valve being kept closed, - closing of the upstream valve, the downstream valve being kept closed, - pressurization of the volume defined by the transfer chamber, until the pressure in it reaches the pressure in the feed chamber of the chemical reactor, - opening of the valve downstream, which allows the transfer of the solid particles into the feed chamber, generally by gravity flow, - closing of the valve downstream, the upstream valve being kept closed, and evacuation of the excess pressure present in the transfer chamber, the evacuated gas being sometimes stored for reuse. The main drawbacks of a lock-latch type transfer system are: a high energy consumption, corresponding to the compression of the gas and to the total depressurization of the airlock, that is to say a very high consumption of pressurizing gas. The electrical energy required for the compression of the gas is of the order of 1% in value and represents approximately 3% in gross energy compared to the lower heating value of the biomass. The gas generally used for pressurization is nitrogen or CO2 and a need for energy is also needed for the manufacture of this gas. This energy is relatively high in the case of biomass (compared to coal) because its mass density is low, as well as its calorific value. - An additional gas supply (N2 or CO2) to empty, after pressurization, the transfer chamber in a buffer tank. a dilution of the biogas by the neutral gas introduced into pressure from the porosities of the biomass. - The valves are in contact with the material to be transferred, likely to damage their operation (shutter, not complete closure by said material).

In an attempt to answer these general problems related to the "lock hopper" transfer system, various solutions have been devised, such as those described in the document US4150759A1, in the document FR2973082A1 and in the document WO2011 / 044911A2. However, these solutions do not yet give complete satisfaction due to the fact that they have all the following disadvantages: - they use several pistons, so the number of mechanical members is high and it follows that the management of the displacement of the pistons is complex, - the pistons are used to push the biomass, which implies the need to have a specific seal at the level of friction with the biomass, - in case of failure in the management of the positioning of the pistons, it is likely to a leak in the seal of the pump appears with a gas leak on the side of the high pressure towards the side of the low pressure.

Finally, there is a need for a transfer system that avoids gas transfers at the pressure prevailing in the second chamber under high pressure (typically 40 bars in the case of a gasification reactor) to the first chamber where there is a pressure close to the atmospheric pressure. Failure to do so results in high levels of energy consumption and possible pollution problems through the transfer of gas. All of these issues may arise for other applications and other types of solid material in granular form other than biomass transfer in a gasification reactor.

OBJECT OF THE INVENTION The object of the present invention is to propose a solids transfer solution in granular form between two chambers under different pressures which overcomes the disadvantages listed above. In particular, an object of the invention is to provide a transfer system and method that are simple and economical, efficient and energy consumption is as low as possible.

Another object of the invention is to provide a transfer system and method that avoids the risk of gas transfer from the second enclosure to the first enclosure at the time of the transition from the communication with the second enclosure to the implementation of communication with the first speaker. These objects can be achieved by a solids transfer system in granular form, a first chamber in which there is a first pressure to a second chamber in which there is a second pressure greater than the first pressure, the transfer system comprising a transfer lock intended to be disposed between the first and second enclosures and delimiting an internal volume, an intake opening adapted to put in fluid communication the internal volume with the first enclosure, an exhaust opening adapted to put in fluid communication the internal volume with the second chamber, a single piston movable inside the transfer lock between first and second positions such that the internal volume varies between a first value occupied in the first position of the piston and a second value occupied in the second piston position and lower than the first value, and a piston displacement control element allowing the passage of the first value to the second value is performed by the piston when the internal volume is in fluid communication with the second chamber and before a fluid communication between the internal volume and the first chamber and that the passage of the second value to the first value is achieved by the piston when the internal volume is in fluid communication with the first chamber. The first and second values of the internal volume are such that the ratio between the first pressure and the second pressure is preferably equal to the ratio between the second value and the difference between the first value and the volume occupied by the granular solid material in the internal volume of the transfer lock and from the first chamber when the internal volume occupies the first value and the internal volume is in fluid communication with the first chamber. In particular, this second value may be substantially zero. Preferably, the passage of the piston from the first position to the second position causes the passage of the exhaust opening of a first state in which the internal volume of the transfer lock is in fluid communication with the second chamber at a second position. state in which the internal volume of the transfer lock is not in fluid communication with the second chamber. The piston occupying its second position can make a closure of the exhaust opening and eliminate any fluid communication between the second chamber and the internal volume of the transfer lock. In a preferred embodiment, the passage of the piston from the first position to the second position causes the passage of the inlet opening of a first state in which the internal volume of the transfer lock is in fluid communication with the first enclosure to a second state in which the internal volume of the transfer lock is not in fluid communication with the first enclosure. The piston occupying its second position can then make a closing of the inlet opening and eliminate any fluid communication between the first chamber and the internal volume of the transfer lock. In a first variant, the transfer lock may comprise a hollow body intended to be fixed in a reference frame connected to the first and second chambers and a rotating chamber movably mounted by pivoting in the hollow body. The rotating chamber may be tubular or spherical and the pivot axis of the rotating chamber may coincide with the straight axis of sliding of the piston relative to the transfer lock. The pivot axis of the rotating chamber can be oriented in a substantially horizontal direction so that the flow of solid material from the first chamber to the second chamber via the transfer lock is practiced in a gravity manner.

The rotating chamber may have a cylindrical outer surface having a cutting section that is a circle and pivotable with respect to an inner surface of the hollow body and an inner surface of cylindrical shape having a sectional section that is a polygonal or circular shape complementary to the cross section of the piston perpendicular to the axis of sliding of the piston. The transfer lock may comprise a granular solid material sealing means disposed between the outer surface of the rotating chamber and the inner surface of the hollow body. The hollow body may comprise first and second through orifices according to its thickness and opening respectively into the first and second enclosures, and the rotating chamber may comprise a single through-light according to its thickness, the light of the rotating chamber varying by pivoting the chamber rotating between: a first position arranged facing the first orifice of the hollow body in which the internal volume is in communication with the first chamber through the light and the first orifice and in which the internal volume is not in fluid communication with the second chamber, - a second position disposed facing the second orifice of the hollow body in which the internal volume is in communication with the second chamber through the light and the second orifice and wherein the internal volume is not in fluid communication with the first speaker.

The first orifice and the second orifice may be aligned in a vertical direction, the first orifice being disposed above the second orifice, allowing the solid material in granular form to flow first gravitationally from the first chamber to the rotating chamber through the light occupying its first position and through the first orifice, and then, after pivoting the rotating chamber, from the rotating chamber to the second chamber through the light occupying its second position and through the second orifice. In a second alternative variant, the transfer lock can comprise a fixed chamber dedicated to the transfer between the two enclosures, a single piston moving inside the fixed chamber so as to vary the internal volume delimited by the fixed chamber between the first and second values, 10 - a first upper valve intended to occupy an open or closed state in which the internal volume respectively is and is not in fluid communication with the first enclosure, - and a second lower valve intended to to occupy an open or closed state in which the internal volume respectively is and is not in fluid communication with the second enclosure. A solid material transfer method in granular form, from a first chamber in which there is a first pressure to a second chamber in which there is a second pressure greater than the first pressure, may comprise a phase of use of such a device. transfer system. This use phase can comprise the following successive steps: a first step of placing the piston in the first position so that the internal volume of the transfer lock takes its first value; a second step of placing the volume in communication internal of the transfer airlock with the first chamber and spill, including gravity, a quantity of solid material in granular form in all or part of the internal volume, - a third step of placing in communication the internal volume of the airlock transfer with the second chamber and discharge into the second chamber, in particular gravity, the amount of solid material in granular form contained in the internal volume, - a fourth step of passage of the first value to the second value by the piston then that the internal volume is in fluid communication with the second enclosure, - a fifth step of placing in communication fluidic communication between the internal volume and the first chamber, removing the fluid communication between the internal volume and the second chamber and then passing from the second value to the first value by the piston.

In the case where the transfer lock comprises a fixed hollow body with respect to the first and second enclosures and a rotating chamber movably mounted by pivoting in the hollow body, the third and fifth steps may comprise the implementation of a pivoting step of the rotating chamber relative to the hollow body. One application of this transfer process may be to supply a gasification reactor with biomass, in which the biomass constitutes the solid material in granular form to be transferred and the second enclosure is constituted by the gasification reactor. BRIEF DESCRIPTION OF THE DRAWINGS Other advantages and features will emerge more clearly from the following description of particular embodiments of the invention given as non-restrictive examples and shown in the accompanying drawings, in which FIGS. show the different steps of an operating cycle of an exemplary transfer system according to the invention.

DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION The transfer system 10 shown in FIGS. 1 to 5 makes it possible to transfer solid material 11 in granular form from a first enclosure E1 in which there is a first pressure P1 towards a second enclosure E2 in which there is a second pressure P2 strictly greater than the first pressure P1. A preferred application will be one in which the solid material 11 is biomass and the second enclosure E2 is a gasification reactor. The first chamber E1 is preferably a storage element for the biomass to be transferred to the gasification reactor via the system 10. In this case, the first pressure P1 is substantially equal to the atmospheric pressure while the second pressure P2 is equal to order of a few tens of bars, for example of the order of 40 bars. In general, the transfer system 10 comprises a transfer lock 12 intended to be disposed between the first enclosure El and the second enclosure E2. The transfer lock 12 delimits a variable internal volume V as indicated below. An inlet opening 13 is able selectively to put or not in fluid communication the internal volume V with the first enclosure E1. There is also an exhaust opening 14 capable of selectively putting or not in fluid communication the internal volume V with the second enclosure E2. The transfer lock 12 comprises a single piston 15 movable within the transfer lock between first and second positions such that the internal volume V varies between a first value occupied in the first position of the piston 15 and a second value occupied. in the second position of the piston 15. The second value is strictly less than the first value. According to an important characteristic, the transfer lock 12 also comprises an element 16 for controlling the displacement of the piston, allowing: - the passage of the first value to the second value is carried out by the piston 15 when the internal volume V is in communication fluidic with the second chamber E2 and before a subsequent fluidic communication between the internal volume V and the first chamber E1, - and the passage of the second value to the first value is performed by the piston 15 when the internal volume V is or is likely to be in fluid communication with the first enclosure E1. More specifically, the single piston 15 comprises a sliding portion housed wholly or partly in a hollow body 17 fixed in a frame linked to the first and second speakers E1, E2. It is the displacement of this moving part which realizes the variation of the internal volume V between the first and second values. The piston may comprise a fixed part, integral with the hollow body 17 and intended to participate in the implementation of the displacement of the movable part selectively in a forward direction and in a return direction from the control commands issued by the element 16 Whatever the nature of the solid material 11 in granular form, there can be provided a means for metering the amount of solid material 11 poured into the transfer lock each time the internal volume is in fluid communication with the first speaker E1. Indeed, at each operating cycle of the transfer system 10, a determined and quantified quantity of material 11 is first discharged into the internal volume from the first enclosure E1 at a time when the internal volume is in fluid communication with the first chamber El and is not in fluid communication with the second chamber E2, then is discharged from the internal volume to the second chamber at a later time when the internal volume is in fluid communication with the second chamber E2 and is no longer in fluidic communication with the first enclosure E1. Preferably, the first value of the internal volume V occupied in the first position of the piston 15 and the second value of the internal volume V occupied in the second position 15 are such that the ratio calculated between, on the one hand, the first pressure P1 and the other the second pressure P2 is equal to the ratio calculated between, on the one hand, the second value of the internal volume V and, on the other hand, the difference between the first value of the internal volume V and the volume occupied by the solid material 11 in granular form in the internal volume V of the transfer chamber 12 and coming from the first enclosure E1 when the internal volume V occupies the first value and the internal volume V is in fluid communication with the first enclosure E1.

To illustrate the general principles above, the piston 15 occupies its first position in FIGS. 1, 2 and 5 where the internal volume V delimited internally by the transfer lock 12 is equal to the first value defined above, while the piston 15 occupies its second position in FIGS. 3 and 4, in which the internal volume V delimited internally by the transfer lock 12 is equal to the second value defined above. It may be advantageous, which corresponds to the embodiment illustrated in Figures 1 to 5, to choose a second value of the internal volume V substantially zero. However, it remains possible to choose a second value of the internal volume V strictly greater than 0 but verifying the inequation explained above with respect to the first and second pressures P1 and P2 and the first value of the internal volume V.

Preferably, the transfer lock 12 comprises, in addition to the hollow body 17, a rotating chamber 18 movably mounted by pivoting in the hollow body 17 about an axis X. As will be detailed later, this pivoting movement of the rotating chamber has the effect of varying positions of a light 19. In order to allow its pivoting movement inside the cavity delimited internally by the hollow body 17 while having a possibility of sealing between the hollow body 17 and the rotating chamber 18 during their relative movement, the rotating chamber 18 is preferably of tubular or spherical shape and the pivot axis X of the rotating chamber 18 coincides with the rectilinear axis of sliding of the piston 15 relative to the transfer lock 12. The ratio of the dimensions between the length and the diameter of the rotating chamber 18 may vary according to the requirements of size and robustness and the flow requirements of solid material 11. Preferably, the rotating chamber 18 has: - an outer surface of cylindrical shape, a section section (seen in a plane perpendicular to the pivot axis X) is a circle and pivoted around X with respect to a inner surface of the same shape of the hollow body 17, - and an inner surface of cylindrical shape, a section section (seen in a plane perpendicular to the axis of sliding of the piston) is a polygonal or circular shape complementary to the section of the section of the piston 15 perpendicular to the axis of sliding of the piston 15.

In the particular case where the piston has a section having a shape which is not cylindrical, the piston must be able to turn about the axis X at the same time as the chamber 18.

Thus, the movable portion of the piston slides inside the cavity delimited internally by the rotating chamber 18 while the latter is able to pivot about X inside the cavity defined by the hollow body.

As will be detailed below, the pivot axis X of the rotating chamber 18 is preferably oriented in a substantially horizontal direction so that the flow of the solid material 11 from the first enclosure El to the second enclosure E2 via the transfer lock 12 is practiced in a gravitational manner. More specifically, the flow or discharge of the solid material 11 of the first chamber E1 to the internal volume V is practiced by gravity and the flow or discharge of the solid material 11 from the internal volume V to the second chamber E2 is also practice by gravity.

However, it may be envisaged that the pivot axis X of the rotating chamber 18 may form an angle with the rectilinear axis of sliding of the piston 15 relative to the transfer lock 12, for example of the order of 90 °. For example, in the case where the rectilinear sliding axis of the piston 15 with respect to the transfer lock 12 is oriented in a horizontal direction, the pivot axis X can be oriented either in another horizontal direction and for example perpendicular, or in a vertical direction, but the spill of material is then no longer practiced by gravity. In the illustrated embodiment, the hollow body 17 comprises a first orifice 20 passing through the thickness of the hollow body perpendicular to the X axis and a second orifice 21 passing through its thickness. The first orifice 20 opens into the first chamber El and the second orifice 21 opens into the second chamber E2. The rotating chamber 18 comprises the light 19 (already mentioned), which is single and through the thickness of the rotating chamber perpendicular to the axis X. The light 19 of the rotating chamber 18 varies by pivoting the rotating chamber 18 between a first position (FIGS. 1, 4 and 5) arranged opposite the first orifice 20 of the hollow body 17 in which the internal volume V is in communication with the first enclosure E1 through the light 19 and the first orifice 20 and in which the internal volume V is not in fluid communication with the second chamber E2, and a second position (FIGS. 2 and 3) disposed opposite the second orifice 21 of the hollow body 17 in which the internal volume V is in communication with the second chamber E2 through the lumen 19 and the second orifice 21 and in which the internal volume V is not in fluid communication with the first enclosure El.

Preferably, the passage of the piston 15 from the first position to the second position concretely causes the passage of the exhaust opening 14 of a first state in which the internal volume V of the transfer lock 12 is in fluid communication with the second enclosure E2 to a second state in which the internal volume V of the transfer lock 12 is not in fluid communication with the second enclosure E2. The first state of the exhaust opening 14 is shown occupied by the material to be transferred in FIG. 2, just before the transfer of the material to the chamber E2. The passage of the piston 15 to its second position in Figures 3 and 4 causes the passage of the exhaust opening 14 in its second state although the light 19 is in its second position. It may in particular be provided that the piston 15 closes the exhaust opening 14 when it occupies its second position and eliminates any fluid communication between the second chamber E2 and the internal volume V of the transfer lock 12 even if the light 19 is in its second position. When the light 19 is not in its second position, the exhaust opening 14 is anyway in its second state because it is closed by the wall of the rotating chamber, regardless of the position adopted by the piston.

In Figures 1 and 5, the exhaust opening 14 occupies its second state although the piston 15 is in its first position due to the fact that the light 19 of the rotating chamber 18 is in its first position. This is the wall of the rotating chamber, placed at the right of the second orifice 21 which closes the exhaust opening 14, the single lumen 19 being opposite the first orifice 20. In addition, the passage of the piston 15 from the first position to the second position preferably causes the passage of the inlet opening 13 of a first state in which the internal volume V of the transfer lock 12 is in fluid communication with the first enclosure E1 to a second state in which the internal volume V of the transfer lock 12 is not in fluid communication with the first enclosure E1. It can in particular be provided that the piston 15 closes the inlet opening 13 when it occupies its second position and eliminates any fluid communication between the first enclosure El and the internal volume V of the transfer lock 12 even if the light 19 is in its first position. When the light 19 is not in its first position, the inlet opening 13 is anyway in its second state because it is closed by the wall of the rotating chamber, regardless of the position adopted by the piston. Thus, in Figure 4, the inlet opening 13 is in its second state even if the light 19 is in its first position. Preferably, the first orifice 20 and the second orifice 21 are aligned in a vertical direction perpendicular to the axis of pivoting of the rotating chamber 18, the first orifice 20 being disposed above the second orifice 21. The solid material 11 in form granularly can flow first gravity first from the first chamber El to the rotating chamber 18 through the lumen 19 occupying its first position and through the first orifice 20, then, after pivoting the rotating chamber 18, the rotating chamber 18 at the second chamber E2 through the light 19 occupying its second position and through the second orifice 21. It follows from the foregoing that it is the meeting of the light 19 of the rotating chamber 18 and the first orifice 20 of the hollow body 17 which constitutes the intake opening 13 and it is the meeting of the light 19 of the rotating chamber 18 and the second orifice 21 of the hollow body 17 which is the exhaust opening 14. The first state of the intake opening 13 corresponds to the configuration adopted when the light 19 is in its first position (provided that the piston 15 is in its first position) and as it there is a single light 19, the exhaust opening 14 is automatically in its second state. By cons, the first state of the exhaust opening 14 corresponds to the configuration adopted after the implementation of a suitable rotation of the rotating chamber 18 so as to place the light 19 of the rotating chamber 18 opposite the second orifice 21 of the hollow body 17 (provided that the piston 15 is in its first position), that is to say when the light 19 is in its second position: as there is only one light 19, the opening admission 13 is automatically in its second state.

Thus, when the intake opening 13 is in its first state, the exhaust opening 14 is necessarily in its second state. Moreover, when the exhaust opening 14 is in its first state, the inlet opening 13 is necessarily in its second state. There is no situation where the two openings 13, 14 are simultaneously in their first states, avoiding any risk of involuntary gas transfer from one enclosure to another. In a preferred embodiment, the transfer lock 12 comprises granular solid material sealing means 11 disposed between the outer surface of the rotating chamber 18 and the inner surface of the hollow body 17. Once the desired amount of solid material 11 is discharged (arrow F1) into the internal volume V (Figure 1), the rotating chamber 18 is rotated (arrow F2) of the order of 180 °. During this rotation, the seal between the first low-pressure enclosure E1 and the second higher-pressure enclosure E2 is permanently ensured in the gap between the outer surface of the rotating chamber 18 and the inner surface of the hollow body 17. Each of the first and second orifices 20, 21 preferably has a dimension in a direction perpendicular to the X axis less than a quarter of the circle of the chamber 18. It is possible to use a technology similar to that of the ball valves or cylindrical. A ball valve (commonly known as a ball valve or quarter-turn valve) is provided with an integral passage or cylindrical hole in a ball rotated (quarter turn) in a spherical chamber, the sealing being carried out directly at the metal-on-metal contact, or on a coating, for example polytetrafluoroethylene. A cylindrical valve allows a full passage through a light made in a rotating cylinder, sealing being made on the cylinder. Rotary locks operate on the same principle with the difference that the cylinder is compartmentalized to dispense powder in a metered manner. Alternatively or in combination, a hydraulic barrier by injection of a low gas flow between the hollow body 17 and the rotating chamber 18 can be implemented to allow on the one hand to avoid the fine dust to be inserted between the inner surface of the hollow body 17 and the outer surface of the rotating chamber 18 and secondly to check the seal by measuring the leakage rate.

The size of the rotating chamber 18 is in particular a function of the solid material flow 11 to be transferred, this flow rate also depending on the duration (typically between 1 and 10 s) of the transfer cycle detailed below. For example, in the case where a flow rate of 1 ton per hour is sought (the cycle having a duration of 5 s for example), it is necessary to implement 720 cycles in one hour. The corresponding volume of material 11 is 5000 L in the case of biomass. In this example, the transfer chamber has a volume of about 7 L: it is possible to provide a diameter of about 20 cm in diameter and a length of about 20 cm. For this dimension of the rotating chamber 18, the light 19 would have a width of the order of 12 or 13 cm in a direction perpendicular to the X axis and a length of about 20 cm along the X axis.

The use of the transfer system 10 may advantageously be as follows.

The solid material transfer 11 in granular form, from the first enclosure El in which the first pressure P1 prevails towards the second chamber E2 in which the second pressure P2 is greater than the first pressure P1, comprises a phase of use of a Such a phase of use preferably comprises the following successive stages: a first placement step (arrow F6) of the piston in the first position (FIG. 1) so that the internal volume V of the transfer lock 12 occupies its first value, - a second step of communication of the internal volume V of the transfer lock 12 with the first chamber El and spill (arrow F1), including gravity, a quantity of solid material 11 in form granularity in all or part of the internal volume V at the first value, - a third step (FIG. 2) of communication of the internal volume V of the transfer chamber. t 12 with the second chamber E2 and discharge (arrow F3) in the second chamber E2 by rotating 180 ° of the rotating chamber 18, including gravity, the amount of solid material 11 in granular form contained in the internal volume V a fourth step (FIG. 3) of passage (arrow F4) from the first value to the second value by the piston 15 while the internal volume V is in fluid communication with the second enclosure E2; a fifth step (FIG. and 5) for fluidic communication between the internal volume V and the first chamber E1, for suppressing the fluidic communication between the internal volume V and the second chamber E2 and then for passing (arrow F6) from the second value to the first value by the piston 15.30 In the particular embodiment where the transfer lock 12 comprises the hollow body 17 fixed relative to the first and second speakers E1, E2 and the rotating chamber 18 pivotably mounted in the hollow body 17, the third and fifth steps comprise the implementation of a pivoting step of the rotating chamber relative to the hollow body. The arrow F2 illustrates the pivoting of the rotating chamber 18 during the third step, of moving the light 19 from the first position to the second position. The arrow F5 illustrates the pivoting of the rotating chamber 18 during the fifth step, of moving the light 19 from the second position to the first position. The pivoting direction during the third step may be the same or opposite to the pivoting direction during the fifth step.

It should be noted that the pivoting of the rotating chamber 18 for the implementation of the fifth step can begin before the piston 15 occupies its second position but the piston 15 must occupy its second position when the internal volume is still in fluid communication with the second speaker E2.

In the illustrated embodiment, the passage of the second value to the first value by the piston 15 is performed after the pivoting step of the rotating chamber 18 which carries out the fluidic communication between the internal volume V and the first enclosure E1 and simultaneously the suppression of the fluidic communication between the internal volume V and the second enclosure E2. In another variant not shown of the transfer system, the transfer lock is constituted by a chamber no longer rotating but instead fixed, dedicated to the transfer between the two speakers E1, E2. The change of state of the openings 13, 14 is no longer practiced by pivoting the chamber but against the transfer lock comprises a first upper valve intended to occupy an open or closed state in which the internal volume V defined by the fixed chamber respectively is and is not in fluid communication with the first enclosure El and a second lower valve intended to occupy an open or closed state in which the internal volume V delimited by the fixed chamber respectively is and is not in fluid communication with the second enclosure E2. In contrast, in the same manner as before, the transfer lock comprises a single piston capable of varying the internal volume between the first and second values, the piston moving within the fixed chamber. In particular, this piston plays a shutter role by occupying the volume of the chamber after the gravitational fall of the solid material 11 in the second chamber E2, to avoid the transfer of gas from the second chamber E2 to the first chamber E1 . The operating cycle of this transfer system variant comprises the same general steps as previously described, which can be implemented concretely by performing the following successive steps: opening of the upper valve on the side of the first enclosure and closing the lower valve on the side of the second chamber, the piston being such that the internal volume occupies the first value, - pouring a determined quantity of solid material 11 into the internal volume of the fixed chamber, thanks to a system dosing system (worm, rotary lock, etc ...), - closing of the upper valve on the side of the first chamber, - opening of the lower valve on the side of the second chamber and gravity discharge of the solid material in the second chamber out of the fixed chamber, - displacement of the piston so that the internal volume V comes to occupy the second value, closing the lower valve on the side of the second chamber, opening the upper valve on the side of the first chamber, moving the piston to change the internal volume from the second value to the first value. It emerges from the two variants previously described that there is a solid material transfer system in granular form between two chambers under different pressures without transfer of gas from the chamber in which there is the greatest pressure towards the chamber in which reigns the least pressure. The transfer of the material may preferentially be done in a gravitational manner. The piston acts as a partial or total closure of the internal volume of the transfer chamber, whether it is rotating or fixed, at the moment of the passage of the fluid communication between this internal volume and the chamber in which the greater pressure to the setting in fluid communication between this internal volume and the enclosure in which reigns the least strong pressure. This thus makes it possible to avoid gas transfer from the high pressure side to the low pressure side, in particular during the rotational return of the chamber in the case of a rotating chamber. This closure occurs at a time when the internal volume is still in fluid communication with the enclosure under high pressure and before a subsequent fluid communication with the enclosure under lower pressure. An advantage of not having gas transfer is also not to expend energy to compress the gas pressure in the first chamber to the pressure in the second chamber (the pressure difference is generally of the order 40 bars for a driven flow gasification reactor), while avoiding the risk of gas transfer from the second chamber to the first chamber. The particular variant of the rotating chamber is an advantageous combination of: - the rotational movement of the chamber for a gravity conveyance between the two chambers at different pressures while ensuring the sealing, - and the closing of this chamber on the side of the highest pressure, to avoid transferring gas from the highest pressure side to the lower pressure side, when returning the chamber. The transfer system and method have the advantages of being simple (one rotating part and one piston) and economical, efficient and of having the lowest possible energy consumption (limited to the only force necessary for the displacement of the piston). piston). They advantageously avoid the risks of gas transfer from the second chamber to the first chamber at the time of the passage from the fluidic communication with the second chamber to the setting in fluid communication with the first chamber. The additional advantages are as follows: - absence of gas consumption, - the sequence of the operating cycle is rapid, essentially limited by the filling and emptying time of the lock chamber by the solid material 11, - the solid material, In particular, the biomass is not pushed by the piston and it falls by gravity drop, - there is no risk of placing the first and second enclosures in communication with a pilot failure, - the flow rate of solid material can be adapted by the cycle frequency, - the system can be extrapolated to several sizes, - it is possible to associate in parallel several transfer systems ente them by a connecting mechanism such as a camshaft or connecting rod to operate simultaneously. Finally, the solution developed above can be used for other applications and other types of solid material in granular form other than the transfer of biomass into a gasification reactor.

Claims (19)

REVENDICATIONS1. Transfer system (10) of solid material (11) in granular form, of a first chamber (El) in which there is a first pressure (P1) to a second chamber (E2) in which a second pressure (P2) prevails at the first pressure (P1), the transfer system (10) comprising a transfer lock (12) intended to be arranged between the first and second enclosures (E1, E2) and delimiting an internal volume (V), an opening inlet (13) adapted to put in fluidic communication the internal volume (V) with the first enclosure (El), an exhaust opening (14) adapted to put in fluid communication the internal volume (V) with the second enclosure ( E2), a single piston (15) movable inside the transfer lock (12) between first and second positions such that the internal volume (V) varies between a first value occupied in the first position of the piston (15) and a second value occupied in the d second position of the piston (15) and lower than the first value, and a control element (16) of the displacement of the piston (15) allowing the passage of the first value to the second value is achieved by the piston (15) when the internal volume (V) is in fluid communication with the second chamber (E2) and before a fluidic communication between the internal volume (V) and the first chamber (El) and that the transition from the second value to the first value is achieved by the piston (15) when the internal volume (V) is in fluid communication with the first chamber (El). 2. Transfer system (10) according to claim 1, characterized in that the first and second values of the internal volume (V) are such that the ratio between the first pressure (P1) and the second pressure (P2) is preferably equal the ratio between the second value and the difference between the first value and the volume occupied by the solid material (11) in granular form in the internal volume (V) of the transfer chamber (12) and coming from the first chamber (El) when the internal volume (V) occupies the first value and the internal volume (V) is in fluid communication with the first chamber (El). 3. Transfer system (10) according to claim 2, characterized in that the second value is substantially zero. 4. Transfer system (10) according to one of claims 1 to 3, characterized in that the passage of the piston (15) from the first position to the second position causes the passage of the exhaust opening (14) a first state in which the internal volume (V) of the transfer lock (12) is in fluid communication with the second chamber (E2) to a second state in which the internal volume (V) of the transfer lock (12) is not in fluid communication with the second enclosure (E2). 5. Transfer system (10) according to claim 4, characterized in that the piston (15) occupies its second position makes a closure of the exhaust opening (14) and eliminates any fluid communication between the second chamber (E2 ) and the internal volume (V) of the transfer lock (12). Transfer system (10) according to one of claims 1 to 5, characterized in that the passage of the piston (15) from the first position to the second position causes the passage of the inlet opening (13). a first state in which the internal volume (V) of the transfer lock (12) is in fluid communication with the first chamber (El) to a second state in which the internal volume (V) of the transfer chamber (12) n is not in fluid communication with the first enclosure (El). 7. Transfer system (10) according to claim 6, characterized in that the piston (15) occupies its second position closes the inlet opening (13) and eliminates any fluid communication between the first chamber (El ) and the internal volume (V) of the transfer lock (12). 8. Transfer system (10) according to one of claims 1 to 7, characterized in that the transfer lock (12) comprises a hollow body (17) intended to be fixed in a frame linked to the first and second chamber ( E1, E2) and a rotating chamber (18) movably pivotally mounted in the hollow body (17). 9. Transfer system according to claim 8, characterized in that the rotating chamber (18) is of tubular or spherical shape and the pivot axis (X) of the rotating chamber (18) coincides with the straight sliding axis. of the piston (15) relative to the transfer lock (12). 10. Transfer system (10) according to claim 9, characterized in that the pivot axis (X) of the rotating chamber (18) is oriented in a substantially horizontal direction so that the flow of the solid material ( 11) from the first enclosure (El) to the second enclosure (E2) via the transfer lock (12) is conveniently provided. 11. Transfer system (10) according to one of claims 9 or 10, characterized in that the rotating chamber (18) has an outer surface of cylindrical shape, a cutting section is a circle and pivotable relative to an inner surface hollow body (17) and a cylindrical inner surface of which a sectional section is a polygonal or circular shape complementary to the section of the piston (15) perpendicular to the sliding axis of the piston (15). The transfer system (10) according to claim 11, characterized in that the transfer lock (12) comprises a granular solid material sealing means (11) disposed between the outer surface of the rotating chamber (18). and the inner surface of the hollow body (17). 13. Transfer system (10) according to one of claims 8 to 12, characterized in that the hollow body (17) comprises first and second orifices (20, 21) through its thickness and opening respectively in the first and second chamber (E1, E2), in that the rotating chamber (18) comprises a single through-light (19) according to its thickness, the light (19) of the rotating chamber (18) varying by pivoting of the rotating chamber (18). ) between: - a first position arranged facing the first orifice (20) of the hollow body (17) in which the internal volume (V) is in communication with the first chamber (El) through the light (19) and the first orifice (20) and in which the internal volume (V) is not in fluid communication with the second chamber (E2), - a second position disposed opposite the second orifice (21) of the hollow body (17) in which the internal volume (V) is in communication with the two th enclosure (E2) through the lumen (19) and the second orifice (21) and wherein the internal volume (V) is not in fluid communication with the first enclosure (El). 14. Transfer system (10) according to claim 13, characterized in that the first orifice (20) and the second orifice (21) are aligned in a vertical direction, the first orifice (20) being arranged above the second orifice (21), allowing the solid material (11) in granular form to flow gravitationally firstly from the first chamber (E1) to the rotating chamber (18) through the light (19) occupying its first position and through the first orifice (20), then, after pivoting the rotating chamber (18), the rotating chamber (18) to the second chamber (E2) through the light (19) occupying its second position and through the second orifice (21). 15. Transfer system (10) according to one of claims 1 to 7, characterized in that the transfer lock comprises - a fixed chamber dedicated to the transfer between the two enclosures (E1, E2), - a single piston moving inside the fixed chamber so as to vary the internal volume (V) delimited by the fixed chamber between the first and second values, - a first upper valve intended to occupy an open or closed state in which the internal volume respectively is and is not in fluid communication with the first enclosure (E1), and a second lower valve for occupying an open or closed state in which the internal volume is respectively and is not in fluid communication with the second enclosure (E2). 16. A solid material transfer in granular form, a first chamber (El) in which a first pressure (P1) prevails to a second chamber (E2) in which there is a second pressure (P2) greater than the first pressure (P1), comprising a phase of using a transfer system (10) according to any one of claims 1 to 15. 17. Transfer method according to claim 16, characterized in that said phase of use comprises the following successive steps: a first step (F6) of placing the piston (15) in the first position so that the internal volume ( V) of the transfer lock (12) occupies its first value, - a second step of communication of the internal volume (V) of the transfer lock (12) with the first chamber (El) and discharge (F1), in particular of gravitationally, of a quantity of solid matter (11) in granular form in all or part of the internal volume (V), - a third step (F2) of communication of the internal volume (V) of the transfer chamber (12). ) with the second chamber (E2) and discharging (F3) in the second chamber (E2), in particular gravitational manner, the quantity of solid matter (11) in granular form contained in the internal volume (V), - a fourth step (F4) of passing from the first value to the d the latter value by the piston (15) while the internal volume (V) is in fluid communication with the second chamber (E2), - a fifth step (F5) of fluid communication between the internal volume (V) and the first enclosure (El), eliminating the fluidic communication between the internal volume (V) and the second chamber (E2) and then passing (F6) from the second value to the first value by the piston. 18. The method of claim 17, characterized in that the transfer lock (12) comprising a hollow body (17) fixed relative to the first and second enclosures (E1, E2) and a rotatable chamber (18) mounted in a movable manner by pivoting in the hollow body (17), the third and fifth steps comprise the implementation of a step (F2, F5) pivoting the rotating chamber (18) relative to the hollow body (17). 19. Application of the transfer process according to any one of claims 16 to 18, for supplying a gasification reactor with biomass, in which the biomass constitutes the solid material (11) in granular form to be transferred, the second enclosure (E2). is constituted by the gasification reactor.