A method of preventing blockage of circulating bed material in a circulating fluidized bed reactor includes collecting a continuously flowing bed of solid particles in a gas lock in a return leg of a reactor, measuring gas lock bed pressure values within the bed of the particles, generating a gas lock bed height indication signal on the basis of measured gas lock bed pressure values. A definition stage includes defining and storing to a control system a range of normal gas lock bed height indication signals, formed in normal circulation flow conditions, as a function of the reactor load, and defining and storing to the digital control system a reactor load dependent alarm criterion. The method includes comparing a current gas lock bed height indication signal with the reactor load dependent alarm criterion, and decreasing the reactor load if the current indication signal fulfils the reactor load dependent alarm criterion.

A method of preventing blockage of circulating bed material in a circulating fluidized bed reactor includes collecting a continuously flowing bed of solid particles in a gas lock in a return leg of a reactor, measuring gas lock bed pressure values within the bed of the particles, generating a gas lock bed height indication signal on the basis of measured gas lock bed pressure values. A definition stage includes defining and storing to a control system a range of normal gas lock bed height indication signals, formed in normal circulation flow conditions, as a function of the reactor load, and defining and storing to the digital control system a reactor load dependent alarm criterion. The method includes comparing a current gas lock bed height indication signal with the reactor load dependent alarm criterion, and decreasing the reactor load if the current indication signal fulfils the reactor load dependent alarm criterion.

A combustor air bar grid for use within a fluidized bed reactor includes at least two main air collector bars in fluid communication with a source of fluidizing gas, a plurality of primary air bars that are transversal to the main air collector bars and arranged on the at least two main air collector bars such that the main air collector bars support them, and in fluid communication to at least two of the main air collector bars. The main air collector bars and the primary air bars define ash removal openings in the air bar grid and a plurality of fluidized nozzles are arranged to each of the primary air bars for fluidizing the bed reactor. A fluidized bed reactor includes such a combustor air bar grid.

The invention relates to an improved method for chemical-looping combustion of a solid hydrocarbon-containing feed using a particular configuration of the reduction zone with: a first reaction zone R1 operating under dense fluidized bed conditions; a second reaction zone R2; a fast separation zone S3 for separation of the unburnt solid feed particles, of fly ashes and of the oxygen-carrying material particles within a mixture coming from zone R2; fumes dedusting S4; a particle stream division zone D7, part of the particles being directly recycled to first reaction zone R1, the other part being sent to an elutriation separation zone S5 in order to collect the ashes through a line 18 and to recycle the dense particles through a line 20 to first reaction zone R1. The invention also relates to a chemical-looping combustion plant allowing said method to be implemented.

The invention relates to an improved method for chemical-looping combustion of a solid hydrocarbon-containing feed using a particular configuration of the reduction zone with: a first reaction zone R1 operating under dense fluidized bed conditions; a second reaction zone R2; a fast separation zone S3 for separation of the unburnt solid feed particles, of fly ashes and of the oxygen-carrying material particles within a mixture coming from zone R2; fumes dedusting S4; a particle stream division zone D7, part of the particles being directly recycled to first reaction zone R1, the other part being sent to an elutriation separation zone S5 in order to collect the ashes through a line 18 and to recycle the dense particles through a line 20 to first reaction zone R1. The invention also relates to a chemical-looping combustion plant allowing said method to be implemented.

A process for producing black powder oxygen carriers for use in a chemical looping combustion unit includes the steps of: (a) removing and collecting the black powder waste material that was formed in a gas pipeline; (b) pre-treating the collected black powder to adjust its spherical shape to avoid attrition and fines production; and (c) activating the black powder to increase its reactivity rate and produce the black powder oxygen carrier that is suitable for use in the chemical looping combustion process as an oxygen carrier.

A process for producing black powder oxygen carriers for use in a chemical looping combustion unit includes the steps of: (a) removing and collecting the black powder waste material that was formed in a gas pipeline; (b) pre-treating the collected black powder to adjust its spherical shape to avoid attrition and fines production; and (c) activating the black powder to increase its reactivity rate and produce the black powder oxygen carrier that is suitable for use in the chemical looping combustion process as an oxygen carrier.

A device with annular spouted fluidized bed can be used for carrying out the majority of the technical processes carried out in fluidized bed devices. The reaction chamber of the device has, throughout at least a part of its height, a downwardly tapering funnel shape with step-structured inner surface. The shape of the reaction chamber, together with the tangential admission thereto of fluidized and other gases, makes it possible to create, in the reaction chamber, an adjustable toroidal fluidized bed, in which the rotation rate of the particles of the material undergoing treatment can be adjusted in both horizontal and vertical planes, and also makes it possible to control the dwell time of particles of different sizes in the reaction zone, the intensity with which materials are treated, and other process parameters.

A device with annular spouted fluidized bed can be used for carrying out the majority of the technical processes carried out in fluidized bed devices. The reaction chamber of the device has, throughout at least a part of its height, a downwardly tapering funnel shape with step-structured inner surface. The shape of the reaction chamber, together with the tangential admission thereto of fluidized and other gases, makes it possible to create, in the reaction chamber, an adjustable toroidal fluidized bed, in which the rotation rate of the particles of the material undergoing treatment can be adjusted in both horizontal and vertical planes, and also makes it possible to control the dwell time of particles of different sizes in the reaction zone, the intensity with which materials are treated, and other process parameters.

A combustor air bar grid for use within a fluidized bed reactor includes at least two main air collector bars in fluid communication with a source of fluidizing gas, a plurality of primary air bars that are transversal to the main air collector bars and arranged on the at least two main air collector bars such that the main air collector bars support them, and in fluid communication to at least two of the main air collector bars. The main air collector bars and the primary air bars define ash removal openings in the air bar grid and a plurality of fluidized nozzles are arranged to each of the primary air bars for fluidizing the bed reactor. A fluidized bed reactor includes such a combustor air bar grid.