Compartmented pulse jet dust collector

Claim 2

IN A DUST COLLECTOR SYSTEM THAT INCLUDES A PLURALITY OF PULSE JET DUST COLLECTOR UNITS FOR FILTERING OPERATION WITH CARRIER GAS AT TYPICAL PULSE JET AIR-TO CLOTH FLOW RATIOS, EACH COLLECTOR UN IT CONVENTIONALLY INCLUDING A DIRTY AIR PLENUM, A CLEAN AIR PLENUM ABOVE THE DIRTY AIR PLENUM, A PLURALITY OF COMPRESSED AIR GAS DISTRIBUTION PIPES MOUNTED IN EACH CLEAR AIR PLENUM, EACH OF SAID PIPES HAVING A PLURALITY OF ORIFICES, A PLURALITY OF ASSEMBLELIES SUPPORTED IN THE DIRTY AIR PLENUM AND EACH COMPRISING A CONVENTIONAL NEEDLED FELT FILTER BAG MOUNTED TO FILTER INCOMING CARRIER GAS AND OUTLET MEANS PROVIDING AN OUTLET PASSAGE FOR DIRECTING FILTERED AIR INTO THE CLEAN AIR PLENUM, EACH OF SAID OUTLET MEANS COMPRISING A VENTURI NOZZLE, EACH ASSEMBLY OF FILTER BAG AND OUTLET MEANS BEING IN JET PULSE CLEANING RELATION TO SEPARATE ONE OF SAID ORIFICES, FOR DIRECTING A PULSE JET THROUGH THE FILTER BAG IN A DIRECTION OPPOSITE TO NORMAL CAN VELOCITY FLOW THERETHROUGH AND A PLURALITY OF FIRST ACTUATING MEANS FOR SEPARATELY CONTROLLING SUPPLY OF COMPRESSED GAS AT A PRESSURE FROM ABOUT 60 TO ABOUT 100 PSIG TO DIFFERENT ONES OF SAID PIPES, AND TIMER MEANS FOR CONTROLLING ACTUATION AND SEQUENCING OF THE FIRST ACTUATING MEANS OF ALL OF SAID COLLECTOR UNITS, AN IMPROVED ARRANGEMENT FOR CLEANING THE FILTER BAGS FOR MAINTAINING NORMAL BAG LIFE AT STABLE AIR-TO-CLO TH FLOW RATIOS WHEN APPLIED TO THE RECOVERY OF EXTERMELY FINE FUME PARTICLES FROM A CARRIER GAS, SAID ARRANGEMENT INCLUDING A COMMON CLEAN GAS OUTLET DUCT, SEPARATE DUCT MEANS ESTABLISHING INDIVIDUAL COMMUNICATIONS BETWEEN EACH OF SAID CLEAN AIR PLENUMS AND SAID COMMON DUCT, SEPARATE DAMPER MEANS FOR CONTROLLING FLOW OF CARRIER GAS FROM EACH OF SAID CLEAN AIR PLENUMS THROUGH THE CORRESPONDING ONE OF EACH SEPARATE DUCT MEANS AND INTO SAID COMMON DUCT, AND A PLURALITY OF SECOND ACTUATING MEANS EACH CONTROLLING ONE OF SAID DAMPER MEANS, SAID TIMER MEANS CONNECTING THE FIRST AND SECOND ACTUATING MEANS IN SEPARATE COMPOSITE SETS, EACH OF SAID LAST-NAMED SETS CONSISTING OF THE PLURALITY OF FIRST ACTUATING MEANS CORRESPONDING TO A PREDETERMINED ONE OF SAID COLLECTOR UNITS AND THE SECOND ACTUATING MEANS CORRESPONDING TO THE SAME COLLECTOR UNIT, SAID TIMER MEANS INCLUDING MEANS FOR SEQUENTIALLY ENERGIZING THE COMPOSITE SETS AT TIME SPACED INTERVALS AND MEANS FOR ENERGIZING THE ACTUATING MEANS OF EACH COMPOSITE SET IN A SEQUENCE WHEREIN THE CORRESPONDING DAMPER MEANS CLOSES FOR A PREDETERMINED DAMPER INTERVAL THAT IS FROM ABOUT 20 TO ABOUT 60 SECONDS IN DURATION TO ALLOW THE CAN VELOCITY OF THE CORRESPONDING COLLECTOR UNIT TO BECOME AND REMAIN MINIMAL AND WHEREIN EACH OF THE CORRESPONDING FIRST ACTUATING MEANS OPERATES IN A PREDETERMINED SEQUENCE OF TIME SPACED PULSE INTERVALS OCCURRING AT A TIME WHEN THE CAN VELOCITY IS MINIMAL THE FIRST PULSE INTERVAL BEGINNING ABOUT 10 SECONDS AFTER THE BEGINNING OF ITS CORRESPONDING DAMPER INTERVAL AND EACH PULSE INTERVAL BEING FROM ABOUT 100 TO ABOUT 150 MILLISECONDS IN DURATION AND THE OFF TIME BETWEEN SUCCESSVE PULSE INTERVALS BEING FROM ABOUT ONE SECOND TO ABOUT 4 SECONDS IN DURATION SUCH THAT EACH PULSE JET ACTS TO DISLODGE THE EXTREMELY FINE FUME PARTICLES FROM WITHIN A MYRIOD OF INTERSTICES IN THE CORRESPONDING FILTER BAG FOR FREE FALL WHILE THE CAN VELOCITY REMAINS MINIMAL.

Claim 3

In a dust collector in accordance with claim 1 and wherein each of said first actuating means comprises a solenoid operably connected to one diaphragm valve to control supply of compressed gas to one gas distribution pipe and wherein each of said second actuating means comprises a solenoid operably connected to position one of said damper means.

Claim 4

In a dust collector system in accordance with claim 1 and wherein each of said first actuating means comprises a solenoid operably connected to one diaphragm valve, electrical means connects a pair of said solenoids to control a pair of said diaphragm valves for simultaneously supplying compressed gas to a pair of gas distribution pipes located in spaced apart relation to the same collector unit and wherein each of said second actuating means comprises a solenoid operably connected to control an air cylinder to position one of said damper means.

Claim 5

In a dust collector system that includes a plurality of pulse jet dust collector units for filtering operation with carrier gas at typical pulse jet air-to-cloth flow ratios; each collector unit conventionally including a dirty air plenum, a clean air plenum above the dirty air plenum, a plurality of compressed air gar distribution pipes mounted in each clean air plenum, each of said pipes having a plurality of orifices, a plurality of assemblies supported in the dirty air plenum and each comprising a conventional needled felt filter bag mounted to filter incoming carrier gas and outlet means providing an outlet passage for directing filtered air into the clean air plenum, each assembly of filter bag and outlet means being in jet pulse cleaning relation to a separate one of orifices, for directing a pulse jet throuGh the filter bag in a direction opposite to normal can velocity flow therethrough, each of said outlet means comprising a venturi nozzle, and a plurality of first solenoid means for separately controlling supply of compressed gas to different ones of said pipes; and timer means for controlling actuation and sequencing of said first solenoid means of all of said collector units; an improved arrangement for cleaning the filter bags for maintaining normal bag life at stable air-to-cloth flow ratios when applied to the recovery of extremely fine fume particles from a carrier gas, said arrangement including a common clean gas outlet duct, separate duct means establishing communication between each of said clean air plenums and said common duct, separate damper means for controlling flow of carrier gas from each of said clean air plenums through the corresponding one of said separate duct means and into said common duct, and a plurality of second solenoid means each controlling one of said damper means, said timer means having a plurality of composite sets of contacts, one for each of said dust collector units, each set of contacts including a plurality of first contact means for separately controlling the first solenoid means associated with the corresponding dust collector unit, and second contact means for controlling energization of the second solenoid means associated with the corresponding dust collector unit; said timer means including cyclically operating means for individually selecting said sets of contacts in a predetermined sequence of time spaced intervals and sequencing means for energizing the selected set of contacts by maintaining energization of the said second contact means thereof for closing the corresponding damper means for a predetermined damper interval that is from about 20 to about 60 seconds in duration to allow the can velocity of the corresponding collector unit to become and remain minimal and by successively energizing the contacts of said plurality of first contact means thereof in a predetermined sequence of time spaced pulse intervals occurring at a time when the can velocity is minimal, the first pulse interval beginning about 10 seconds after the beginning of its corresponding damper interval and each pulse interval being from about 100 to about 150 milliseconds in duration and the off time between successive pulse intervals being from about one second to about 4 seconds in duration such that each pulse jet acts to dislodge the extremely fine fume particles from within a myriod of interstices in the corresponding filter bag for free fall while the can velocity remains minimal.

Claim 6

In a dust collector system that includes a plurality of pulse jet dust collector units for filtering operation with carrier gas at typical pulse jet air-to-cloth flow ratios; each collector unit conventionally including a dirty air plenum, a clean air plenum above the dirty air plenum, a plurality of compressed air gar distribution pipes mounted in each clean air plenum, each of said pipes having a plurality of orifices, a plurality of assemblies supported in the dirty air plenum and each comprising a conventional needled felt filter bag mounted to filter incoming carrier gas and outlet means providing an outlet passage for directing filtered air into the clean air plenum, each assembly of filter bag and outlet means being in jet pulse cleaning relation to a separate one of orifices, for directing a pulse jet throuGh the filter bag in a direction opposite to normal can velocity flow therethrough, each of said outlet means comprising a venturi nozzle, and a plurality of first solenoid means for separately controlling supply of compressed gas to different ones of said pipes; and timer means for controlling actuation and sequencing of said first solenoid means of all of said collector units; an improved arrangement for cleaning the filter bags for maintaining normal bag life at stable air-to-cloth flow ratios when applied to the recovery of extremely fine fume particles from a carrier gas, said arrangement including a common clean gas outlet duct, separate duct means establishing communication between each of said clean air plenums and said common duct, separate damper means for controlling flow of carrier gas from each of said clean air plenums through the corresponding one of said separate duct means and into said common duct, and a plurality of second solenoid means each controlling one of said damper means, said timer means having a plurality of composite sets of contacts, one for each of said dust collector units, each set of contacts including a plurality of first contact means for separately controlling the first solenoid means associated with the corresponding dust collector unit, and second contact means for controlling energization of the second solenoid means associated with the corresponding dust collector unit; said timer means including cyclically operating means for individually selecting said sets of contacts in a predetermined sequence of time spaced intervals and sequencing means for energizing the selected set of contacts by maintaining energization of the said second contact means thereof for closing the corresponding damper means for a predetermined damper interval that is from about 20 to about 60 seconds in duration to allow the can velocity of the corresponding collector unit to become and remain minimal and by successively energizing the contacts of said plurality of first contact means thereof in a predetermined sequence of time spaced pulse intervals occurring at a time when the can velocity is minimal, the first pulse interval beginning about 10 seconds after the beginning of its corresponding damper interval and each pulse interval being from about 100 to about 150 milliseconds in duration and the off time between successive pulse intervals being from about one second to about 4 seconds in duration such that each pulse jet acts to dislodge the extremely fine fume particles from within a myriod of interstices in the corresponding filter bag for free fall while the can velocity remains minimal.