Abstract: Heat exchanger (100, 200) for cooling contaminated fluids and which are subjected to variable thermal load, by means of heat transfer to a receiving liquid and/or vapor fluid, said heat exchanger comprising a tube bundle consisting of a plurality of independent tubes (1), two plenums (9, 10, 109, 110), plates (12, 13, 112, 113), and characterized in that said independent tubes (1) comprise an inner tube (2, 102) in which the contaminated gas flows, and an outer tube (3, 103) being said inner tube (2, 102) and outer tube (3, 103) coaxial and where between the outer surface (2?, 102?) of the inner tube (2, 102) and the inner surface (31, 103?) of the outer tube (3, 103) is defined an annular passage G in which flows the receiving fluid and in that said inner tube (2, 102) is welded to the plate (12, 112) in a gas inlet section, while a gas outlet section is guided in a corresponding hole of the plate (13, 113), so that the inner tube (2, 102) expansion in an axial direction is not constrained.

Abstract: A method for producing syngas from preferably vegetal biomass is described. The method provides for the use of a fixed bed gasifier, equipped with two reactors. The biomass is fed to both reactors together with a primary flow rate of air. Advantageously, the method according to the present invention is different from the known art since a secondary flow rate of air is withdrawn from the first reactor at the area where the biomass dries, and fed to the second reactor at the area where the biomass dries, and vice versa, alternately during time. Alternatively, an oscillating air flow is created in each reactor. The achievable result is a greater syngas production, but not exclusively. The syngas quality is improved too, since the biomass has a longer time for completing the gasification reactions.

Abstract: Method for the calculation of the working fluid loss in an organic Rankine cycle plant, comprising at least one evaporator (1), a preheater (5), a turbine (2), a condenser (3), a pump (4), a collecting well (7) and a process piping (8), wherein said working fluid, when the plant is stopped, is in part present in known volumes inside the plant and partly drained in at least a storage tank (6) comprising at least three rooms or volumes: —a first volume (Vck) for storing the fluid to be measured, —a second volume (Vc) having a restricted section for measuring the volume of fluid stored in said first volume (Vck), —a third volume (Vckd) containing the portion of the fluid already measured, wherein, in said method, the working fluid loss of the plant is calculated as the difference between the fluid amount measured in two different instants of time.

Abstract: A turbine of an organic Ranking cycle ORC is described, the turbine comprising a shaft supported by bearings and a plurality of seals arranged round the shaft for confining the operating fluid expanding in the turbine. The seals define at least four axially consecutive chambers. The operating fluid, with function of barrier fluid, is fed into one of the chambers adjacent to turbine stages; a gas, preferably inert, is fed into one of the chambers adjacent to the bearings, and the corresponding seals are gas seals. This configuration prevents the operating fluid from any kind of contamination by the lubricant used for the bearings, and avoids polluting the environment.

Abstract: A method and a turbine for expanding an organic operating fluid in a Rankine cycle includes the step of feeding the operating fluid to a turbine provided with a plurality of arrays of stator blades alternating with a plurality of arrays of rotor blades, to define corresponding turbine stages, constrained to a shaft which rotates on the respective rotation axis. The method also includes: a) causing a first expansion of the operating fluid in one or more radial stages of the turbine, b) diverting the operating fluid exiting from the radial stages in a direction axial and tangential with respect to the rotation axis, and c) causing a second fluid expansion in one or more axial stages of the turbine. Step b) corresponds to an enthalpy change of the operating fluid equal to at least 50% of the average enthalpy change provided for completing the fluid expansion in the turbine.

Abstract: A fluid sealing device for rotating machines having a rotor part including at least one disk carried by a rotating shaft rotating in and relatively to a stator part in the presence of a fluid is disclosed. The rotating shaft has a sealing system defining a first environment at a first pressure. The stator part has a wall in front of the disk of the stator part defining a second environment therewith containing a fluid at a second pressure. The device includes a movable ring placed between the wall of the stator part and the disk of the rotor part and has a front sealing gasket facing towards the disk. The movable ring is moved in the active position when the rotating machine is stopped to prevent the fluid passage from one environment to the other.

Abstract: Heat exchanger (100, 200) for cooling contaminated fluids and which are subjected to variable thermal load, by means of heat transfer to a receiving liquid and/or vapor fluid, said heat exchanger comprising a tube bundle consisting of a plurality of independent tubes (1), two plenums (9, 10, 109, 110), plates (12, 13, 112, 113), and characterized in that said independent tubes (1) comprise an inner tube (2, 102) in which the contaminated gas flows, and an outer tube (3, 103) being said inner tube (2, 102) and outer tube (3, 103) coaxial and where between the outer surface (2?, 102?) of the inner tube (2, 102) and the inner surface (31, 103?) of the outer tube (3, 103) is defined an annular passage G in which flows the receiving fluid and in that said inner tube (2, 102) is welded to the plate (12, 112) in a gas inlet section, while a gas outlet section is guided in a corresponding hole of the plate (13, 113), so that the inner tube (2, 102) expansion in an axial direction is not constrained.

Abstract: A method for producing syngas from preferably vegetal biomass is described. The method provides for the use of a fixed bed gasifier, equipped with two reactors. The biomass is fed to both reactors together with a primary flow rate of air. Advantageously, the method according to the present invention is different from the known art since a secondary flow rate of air is withdrawn from the first reactor at the area where the biomass dries, and fed to the second reactor at the area where the biomass dries, and vice versa, alternately during time. Alternatively, an oscillating air flow is created in each reactor. The achievable result is a greater syngas production, but not exclusively. The syngas quality is improved too, since the biomass has a longer time for completing the gasification reactions.

Abstract: The invention relates to an ORC (Organic Rankine Cycle) for the conversion of thermal energy into electric energy, comprising at least one heat exchanger unit for re-superheating the working fluid by means of the thermovector fluid from the hot source, between the discharge of the first expander and the input of the second expander, and a regenerator unit including a first regenerator and at least one second regenerator for regenerating the working fluid in at least two successive stages, in said first regenerator and at least in said second regenerator respectively, with an additional regenerative heat exchange along the flow line connecting the liquid working fluid output of the second regenerator to the liquid working fluid input of the first regenerator.

Abstract: The invention concerns an ORC plant (Organic Rankine Cycle) for a conversion of thermal energy into electric energy, that comprises a heat exchange group for the exchange of heat between the thermal carrier fluid and a working fluid destined to feed at least one expander connected to an electric generator. The heat exchanger group comprises in succession at least one primary heater and a primary evaporator respectively for preheating and evaporation of the working fluid.

Abstract: The invention concerns a turbine for the expansion of gas and vapor, comprising a body or case, a fixed external sleeve member, overhanging frontally from a frontal wall of said case, and a turbine shaft (15) extending coaxially and rotating in said external sleeve member (18) with the interposition of a supporting unit (19). The external sleeve member has a head flange to axially hold said supporting unit; the turbine shaft ends with a joint to connect it to a device to be operated. The supporting unit (19) includes ball bearings to support the turbine shaft (15) in said external sleeve member (18), and between said external sleeve member (18) and a contiguous end of said turbine shaft (15) an aggregate (50) is provided to generate an adjustable axial force so as to compensate the axial thrust of the turbine shaft to limit the application of improper axial loads on the ball bearings.

Abstract: It is described a method and a turbine for expanding an organic operating fluid in a Rankine cycle, the method comprising the step of feeding the operating fluid to a turbine provided with a plurality of arrays of stator blades (S1-S4, AR) alternating with a plurality of arrays of rotor blades (R1-R5), to define corresponding turbine stages, constrained to a shaft which rotates on the respective rotation axis. The method comprises the further steps of: a) causing a first expansion of the operating fluid in one or more radial stages (S1-S3, R1-R3) of the turbine, b) diverting (AR) the operating fluid exiting from the radial stages in a direction axial and tangential with respect to the rotation axis, and c) causing a second fluid expansion in one or more axial stages (R4, S4, R5) of the turbine. Step b) corresponds to an enthalpy change of the operating fluid equal to at least 50% of the average enthalpy change provided for completing the fluid expansion in the turbine.

Abstract: The invention concerns a turbine structure for the expansion of gas and vapour, comprising a body or casing with a peripheral work fluid transit volute from an entrance to an exit passage, at least a first stator and possible subsequent stators, a turbine shaft rotating around an axis and carrying at least a first rotor and possible subsequent rotors working together downstream of the first stator and subsequent rotors, respectively, an external tube member jutting out frontally from said body or casing and coaxial to the rotating turbine shaft, and where between the tube member (18) and the turbine shaft (15) is positioned a supporting unit (19) extractable en bloc from said external tube (18) except for the shaft.

Abstract: The invention is directed to an ORC (Organic Rankine Cycle) system at least partially co-generative for the production of electric energy and the heating of a fluid. The system includes at least two regenerative exchangers positioned in series on the route of the work fluid between the exit of an electric expander-generator group and the entrance of a condenser of the ORC system, and a heat exchanger-user connected by means of an offtake line to at least one of said regenerative exchangers to receive from them a part of the capacity of work fluid and crossed by the user fluid to be heated by means of a thermal exchange with said capacity of work fluid. A part of the capacity of the work fluid on exiting from the user exchanger is returned to the same regenerative exchanger.

Abstract: The invention regards a turbine for the expansion of gas and vapor that comprises a body or casing with a volute for the transit of the fluid from an input to an output passage through at least a statoric and a rotoric group, a possible front shield that extends radially from said volute towards the axis of the turbine shaft, an external tube member fixed in front of said shield or said volute designed to hold the turbine shaft with the interposition of a supporting unit (19), where said turbine shaft (15) has a head (15?) supporting the rotoric group (16, 17). The turbine shaft (15) together with the rotoric group (16, 17) is movable axially between a work position, in which the head of said shaft is at a distance from an internal end of the external tube member (18) facing towards the statoric group, and a retracted position, in which the head of the shaft or a part of the rotoric group rests against said internal end of said tube member with the interposition of at least a front seal (41).

Abstract: The invention concerns an ORC plant (Organic Rankine Cycle) for a conversion of thermal energy into electric energy, that comprises a heat exchange group for the exchange of heat between the thermal carrier fluid and a working fluid destined to feed at least one expander connected to an electric generator. The heat exchanger group comprises in succession at least one primary heater and a primary evaporator respectively for preheating and evaporation of the working fluid.

Abstract: A fluid sealing device for rotating machines having a rotor part including at least one disk carried by a rotating shaft rotating in and relatively to a stator part in the presence of a fluid is disclosed. The rotating shaft has a sealing system defining a first environment at a first pressure. The stator part has a wall in front of the disk of the stator part defining a second environment therewith containing a fluid at a second pressure. The device includes a movable ring placed between the wall of the stator part and the disk of the rotor part and has a front sealing gasket facing towards the disk. The movable ring is moved in the active position when the rotating machine is stopped to prevent the fluid passage from one environment to the other.

Abstract: The invention relates to an ORC (Organic Rankine Cycle) for the conversion of thermal energy into electric energy, comprising at least one heat exchanger unit for re-superheating the working fluid by means of the thermovector fluid from the hot source, between the discharge of the first expander and the input of the second expander, and a regenerator unit including a first regenerator and at least one second regenerator for regenerating the working fluid in at least two successive stages, in said first regenerator and at least in said second regenerator respectively, with an additional regenerative heat exchange along the flow line connecting the liquid working fluid output of the second regenerator to the liquid working fluid input of the first regenerator.

Abstract: The invention is directed to an ORC (Organic Rankine Cycle) system at least partially co-generative for the production of electric energy and the heating of a fluid. The system includes at least two regenerative exchangers positioned in series on the route of the work fluid between the exit of an electric expander-generator group and the entrance of a condenser of the ORC system, and a heat exchanger-user connected by means of an offtake line to at least one of said regenerative exchangers to receive from them a part of the capacity of work fluid and crossed by the user fluid to be heated by means of a thermal exchange with said capacity of work fluid. A part of the capacity of the work fluid on exiting from the user exchanger is returned to the same regenerative exchanger.