Method and device for the continuous gravimetric metering of flowing materials for burner systems
A method for the continuous gravimetric metering of flowing materials for burner systems, in which the instantaneous mass flow is determined and metering occurs by means of a metering unit can be achieved by means of determination of the type of flowing material. The instantaneous heat output for the flowing material is determined from the type of flowing material and the heat capacity thereof and the mass flow determination. The output from the metering device is regulated to match the set feed rate, depending on the instantaneous heat output. In addition, a device for the continuous gravimetric metering of flowing materials for burner systems comprises a metering unit by means of which the flowing material can be metered. Also provided is a material recognition system for determining the type of the flowing material, an arithmetic unit for determining the instantaneous heat output of the flowing material and a metering controller by means of which the output from the metering unit is regulated to match the set feed rate, depending on the instantaneous heat output.
1. A method for the continuous gravimetric metering of flowing materials for burner systems, with the instantaneous mass flow being determined and the metering occurring with a metering device, wherein
the type of each flowing material is determined, the known individual calorific value from the type of each flowing material is determined and the instantaneous calorific value of the flowing materials is determined from the determination of the mass flow and the output from the metering device is regulated in adjustment to the set-point conveying rate depending on the instantaneous calorific value.
2. A method according to claim 1 , wherein the determination of type of flowing material is carried out by way of NIR spectroscopy.
3. A method according to claim 1 , wherein the flowing materials are plastic materials.
4. A method according to claim 1 , wherein the output of the metering device is regulated by taking into account the distance between metering device and burner system.
5. A method according to claim 1 , wherein the output of the metering device is controlled or regulated by changing the speed of the metering device.
6. A method according to claim 1 , wherein the output of the metering device is regulated in the case of pneumatic conveyance by changing the air quantity and/or air speed.
7. An apparatus for the continuous gravimetric metering of flowing materials for burner systems, with the instantaneous mass flow being determined and with the flowing materials being metered by means of a metering device, wherein
there are provided a material recognition system for determining any kind of flowing material, a computer unit configured to receive information from the material recognition system and to determine the instantaneous calorific value of the flowing materials, and a metering control unit configured to adjust the output of the metering device to the set-point conveying rate based on the instantaneous calorific value.
8. An apparatus according to claim 7 , wherein the material recognition system comprises a contactless material sensor and a radiation source with which the flowing material can be irradiated with a radiation to which the material sensor is sensitive.
9. An apparatus according to claim 8 , wherein the material sensor is an NIR spectroscopic sensor and the radiation source emits light in the near-infrared range, especially that the radiation source is a halogen lamp.
10. An apparatus according to claim 7 , wherein the material recognition system is arranged directly before the metering device.
11. An apparatus according to claim 7 , wherein the flowing materials are plastic materials.
12. An apparatus according to claim 7 , wherein the burner system is a rotary kiln for cement production.
13. An apparatus according to claim 7 , wherein the metering device and the flow meter form a unit, especially a rotary metering weigher.