System for preheating glass melting furnace batch materials
A system for preheating batch materials in a glass melting furnace includes a preheater having an outlet through which fluid is exhausted and an inlet that receives fluids exhausted from the furnace and recirculated from the preheater outlet. In one embodiment, a cyclonic separator has an inlet in communication with the preheater outlet and an outlet in fluid communication with a fan. A controller controls the speed of the fan responsive to a drop in pressure between the separator inlet and outlet and a temperature at the separator outlet. In other embodiments, controllers control valves that (i) control the amount of fluids exhausted from the preheater that are delivered to a flue and recirculated to the preheater or (ii) control the amount of fluids diverted to charger for the furnace, in response to temperatures in a duct coupled to the preheater inlet.
1. A system for preheating batch materials prior to delivery to a glass melting furnace, comprising:
a preheater configured to receive unheated batch materials and to deliver heated batch materials, the preheater including a primary outlet configured to exhaust fluid from the preheater and a primary inlet configured to receive exhaust fluids from the glass melting furnace and exhaust fluids recirculated from the primary outlet of the preheater;
a cyclonic separator having an inlet in fluid communication with the primary outlet of the preheater and an outlet configured to exhaust fluids from the cyclonic separator;
a fan in fluid communication with the outlet of the cyclonic separator;
a pressure sensor configured to generate a pressure signal indicative of a drop in pressure between the inlet and the outlet of the cyclonic separator;
a temperature sensor configured to generate a temperature signal indicative of a temperature at the outlet of the cyclonic separator; and,
a cyclonic flow controller configured to control a speed of the fan responsive to the pressure signal and the temperature signal.
2. The system of claim 1 wherein the cyclonic flow controller is further configured, in controlling the speed of the fan, to:
receive a target flow rate signal indicative of a desired fluid flow rate through the cyclonic separator;
determine an actual flow rate through the cyclonic separator responsive to the pressure signal and the temperature signal; and,
adjust the speed of the fan if the actual flow rate meets a predetermined condition relative to the target flow rate.
3. The system of claim 2 , further comprising a temperature controller configured to generate the target flow rate signal responsive to the temperature signal.
4. The system of claim 3 , further comprising a valve configured to control fluid flow from the fan to a bypass inlet of the preheater.
5. The system of claim 4 wherein the temperature controller is further configured to transmit a valve control signal for controlling a position of the valve responsive to the temperature signal.
6. The system of claim 5 wherein the target flow rate signal and the valve control signal are generated in response to the temperature signal in accordance with a predefined split range control profile.
7. The system of claim 1 , further comprising:
a valve configured to control fluid flow tip a bypass inlet of the preheater from a flue carrying exhaust fluid from the glass melting furnace; and,
a bypass valve controller configured to transmit a valve control signal for controlling a position of the valve responsive to the temperature signal.
8. The system of claim 1 , further comprising a valve configured to control fluid flow from the fan to a bypass inlet of the preheater.
9. The system of claim 8 , further comprising a temperature controller configured to transmit a valve control signal for controlling a position of the valve responsive to the temperature signal.