Patent Number: 
Section: claims

1. A method to determine an operational period for a filter in a filtration device comprising:determining an initial remaining operational period based on an installation date of the filter and an initial expected operational period, wherein the initial expected operational period is determined before the filter starts filtration;periodically calculating a remaining actual operational period of the filter based on the remaining operational period based and an elapsed operational period of the filtration;monitoring an opacity of gases through the filter, andperiodically adjusting the calculated remaining actual operational period based on the monitored opacity. 2. The method of claim 1 wherein the filtration device is a bag house and the filter is an array of bag filters, and further comprising replacing the bag filters at or before the expiration of the adjusted remaining actual operational period. 3. The method of claim 1 wherein the operational period is a filter life. 4. A method for dynamically determining a remaining actual operational life a bag filter in a bag house having a controller, the method comprising:entering into the controller bag filter data and an installation date of the bag filter in the bag house;determining an initial bag filter life based on the bag filter data;decrementing the initial bag filter life to determine a remaining actual bag filter life and periodically decrementing the remaining actual bag filter life;monitoring a bag house operating condition, wherein the operating condition includes the opacity of a gas having passed through the bag filter;adjusting the remaining actual bag filter life based on the monitored bag house operating condition and periodically decrementing the remaining actual bag filter life, andreplacing the bag filter at a time based on the decremented, adjusted remaining actual bag filter life. 5. The method of claim 4 wherein bag house operating condition is the pressure differential and the pressure differential is determined promptly after a bag filter cleaning operation. 6. The method of claim 4 wherein the bag house operating condition is the particulate level and the method further comprises:determining a difference between the particulate level and a baseline particulate level, wherein the baseline particulate level is a function of remaining bag life, andadjusting the remaining bag life to reduce the difference. 7. The method of claim 4 wherein the remaining actual bag life is displayed on a user terminal in communication with the controller. 8. An apparatus for dynamically determining a remaining actual operational life of a filter in a filtration device, comprising:a non-transitory electronic storage containing data including an installation date of the filter, and data indicating an initial filter life;a sensor monitoring a particulate level in an outlet gas flow from the filtration device, and the sensor includes an exhaust gas opacity sensor in the outlet gas flow from the filtration device;a computer controller including an executable program stored on the electronic storage, wherein the execution of the program causes the controller to determine a remaining actual operational filter life based on a difference between a sensed level exhaust gas opacity provided by the opacity sensor and an expected opacity level, wherein the expected opacity level is determined by the controller based on opacity data stored in the electronic storage correlating the expected opacity level to an operational period of the filter, anda user terminal indicating the remaining actual filter life. 9. The apparatus as in claim 8 further comprising a filter cleaning device coupled to the filter and the executable program periodically commands the filter cleaning devices to remove dust and particles from the filter. 10. The apparatus as in claim 8 wherein the filtration device is a bag house and the filter is at least one bag filter. 11. The apparatus as in claim 8 wherein the opacity data is a lookup table which correlates various periods of expected remaining life to various opacity levels. 12. The apparatus as in claim 8 wherein the wherein the filter is an array of bag filters arranged in the device. 13. The apparatus as in claim 8 wherein the filter is a porous material.