A watertube panel portion for a fluidized bed reactor and a corresponding method. The watertube panel portion includes multiple parallel metal tubes having a tube length L1, an outer surface, an original outer diameter OD1, and an original wall thickness WT1, and a circumferentially extending recess formed in a central portion of each of the tubes, between first and second end portions. The recess has a constant depth D that is less than the wall thickness WT1. The recess encircles the outer surface of the central portion of the metal tube. A circumferentially extending metal coating has a constant thickness of at most the depth D of the recess to blanket the recess of each of the multiple metal tubes. A fin is continuously welded between each pair of adjacent tubes.

A circular fluidizing bed combustion system with uniform airflow distributing device is provided. The system comprises a fluidizing bed and a uniform airflow distributing device. The fluidizing bed is comprised of a fluidizing bed boiler body, an airflow distributing plate and a plurality of air caps, wherein, the airflow distributing plate is provided inside the fluidizing bed boiler body and divides the inner space of the fluidizing bed boiler body into a fluidizing chamber which is located in the upper portion of the boiler body and an air chamber which is located in the lower portion of the boiler body, and the plurality of air caps are arranged on the airflow distributing plate for injecting the fluidizing air into the fluidizing chamber. The inner space of the air chamber is divided into a distributing chamber that is located under the airflow distributing plate and an air inlet chamber that is located on one side of the distributing chamber by means of a perforated plate. The distributing chamber is comprised of a front wall, two side walls, a top wall that extends upwards obliquely from the upside of the front wall, and a bottom wall extends downwards obliquely from the downside of the front wall. A first guide plate, a second guide plate and a third guide plate are installed in the distributing chamber. This system makes the flow of the fluidizing air entered into the fluidizing chamber through each air cap uniform, and enhances the combusting efficiency of the coal powder in the fluidizing chamber.

A circular fluidizing bed combustion system with uniform airflow distributing device is provided. The system comprises a fluidizing bed and a uniform airflow distributing device. The fluidizing bed is comprised of a fluidizing bed boiler body, an airflow distributing plate and a plurality of air caps, wherein, the airflow distributing plate is provided inside the fluidizing bed boiler body and divides the inner space of the fluidizing bed boiler body into a fluidizing chamber which is located in the upper portion of the boiler body and an air chamber which is located in the lower portion of the boiler body, and the plurality of air caps are arranged on the airflow distributing plate for injecting the fluidizing air into the fluidizing chamber. The inner space of the air chamber is divided into a distributing chamber that is located under the airflow distributing plate and an air inlet chamber that is located on one side of the distributing chamber by means of a perforated plate. The distributing chamber is comprised of a front wall, two side walls, a top wall that extends upwards obliquely from the upside of the front wall, and a bottom wall extends downwards obliquely from the downside of the front wall. A first guide plate, a second guide plate and a third guide plate are installed in the distributing chamber. This system makes the flow of the fluidizing air entered into the fluidizing chamber through each air cap uniform, and enhances the combusting efficiency of the coal powder in the fluidizing chamber.

The invention relates to a method for operating a fluidized bed boiler, comprising carrying out the combustion process with a fluidized bed comprising ilmenite particles, wherein the average residence time of the ilmenite particles in the boiler is at least 75 hours. The invention further relates to ilmenite particles obtainable by a corresponding method and the use of said ilmenite particles as oxygen-carrying material.

The invention relates to a method for operating a fluidized bed boiler, comprising carrying out the combustion process with a fluidized bed comprising ilmenite particles, wherein the average residence time of the ilmenite particles in the boiler is at least 75 hours. The invention further relates to ilmenite particles obtainable by a corresponding method and the use of said ilmenite particles as oxygen-carrying material.

A watertube panel portion for a fluidized bed reactor and a corresponding method. The watertube panel portion includes multiple parallel metal tubes having a tube length L1, an outer surface, an original outer diameter OD1, and an original wall thickness WT1, and a circumferentially extending recess formed in a central portion of each of the tubes, between first and second end portions. The recess has a constant depth D that is less than the wall thickness WT1. The recess encircles the outer surface of the central portion of the metal tube. A circumferentially extending metal coating has a constant thickness of at most the depth D of the recess to blanket the recess of each of the multiple metal tubes. A fin is continuously welded between each pair of adjacent tubes.

A circular fluidizing bed combustion system with uniform airflow distributing device is provided. The system comprises a fluidizing bed and a uniform airflow distributing device. The fluidizing bed is comprised of a fluidizing bed boiler body, an airflow distributing plate and a plurality of air caps, wherein, the airflow distributing plate is provided inside the fluidizing bed boiler body and divides the inner space of the fluidizing bed boiler body into a fluidizing chamber which is located in the upper portion of the boiler body and an air chamber which is located in the lower portion of the boiler body, and the plurality of air caps are arranged on the airflow distributing plate for injecting the fluidizing air into the fluidizing chamber. The inner space of the air chamber is divided into a distributing chamber that is located under the airflow distributing plate and an air inlet chamber that is located on one side of the distributing chamber by means of a perforated plate. The distributing chamber is comprised of a front wall, two side walls, a top wall that extends upwards obliquely from the upside of the front wall, and a bottom wall extends downwards obliquely from the downside of the front wall. A first guide plate, a second guide plate and a third guide plate are installed in the distributing chamber. This system makes the flow of the fluidizing air entered into the fluidizing chamber through each air cap uniform, and enhances the combusting efficiency of the coal powder in the fluidizing chamber.

A sealpot for a combustion power plant includes a downcomer standpipe which receives solids of the combustion power plant, a bed including a first end and a second opposite end, the first end connected to the downcomer standpipe, a discharge standpipe disposed at the second opposite end of the bed, and an orifice plate disposed between the bed and the discharge standpipe separating the discharge standpipe from the bed. The orifice plate includes apertures disposed at a height above the bed which allow transport of fluidized solids and gas through the orifice plate.

A sealpot for a combustion power plant includes a downcomer standpipe which receives solids of the combustion power plant, a bed including a first end and a second opposite end, the first end connected to the downcomer standpipe, a discharge standpipe disposed at the second opposite end of the bed, and an orifice plate disposed between the bed and the discharge standpipe separating the discharge standpipe from the bed. The orifice plate includes apertures disposed at a height above the bed which allow transport of fluidized solids and gas through the orifice plate.

Disclosed is a process for producing an alloyed, in particular multiple-alloyed aluminide or chromide layer on a component by alitizing or chromizing. First a green compact layer (9) consisting of a binder (5) and metal particles (7) is deposited on the component (1) to be coated and then alitizing or chromizing is carried out, binder and metal particles being deposited on the component separately from one another, first the binder and then the metal particles. A turbine component produced by this process is also disclosed.