Abstract 1. INTE THE METHOD OF CLEANING BY BACKWASHING A LIQUID FILTER BED FORMED OF SOLID HARD PARTICLES HAVING A SPECIFIC GRAVITY APPRECIABLY GREATER THAN THAT OF THE MATTER REMOVED FROM THE LIQUID FILTERED THROUGH SAID BED, THE IMPROVEMENT WHICH COMPRISES INITIALLY RECYCLING THE LIQUID TO BE FILTERED UPWARDLY THROUGH SAID BED AS BACK WASHING LIQUID WHILE PASSING A GAS UPWARDLY THROUGH SAID BED, THE COMBINED FLOW OF SAID LIQUID AND SAID GAS BEING CONTROLLED TO CAUSE AT LEAST 25% EXPANSION OF THE SETTLED VOLUME OF SAID BED AND VIGOROUS RANDOM MOVEMENT OF SAID SOLID PARTICLES WITHOUT ENTRAINMENT OF SAID SOLID PARTICLES IN SAID LIQUID OF MATTER PREVIOUSLY DEPOSITED IN TRAINMENT IN SAID LIQUID OF MATTER PREVIOUSLY DEPOSITED IN SAID BED, SAID RECYCLING OF SAID LIQUID TOGETHER WITH SUSPENDED AND ENTRAINED MATTER BEING CONDUCTED BY PUMPING SAID LIQUID FROM ABOVE SAID BED INTO THE BOTTOM OF SAID BED, PARTIALLY REMOVING SAID SUSPENDED AND ENTRAINED MATTER FROM SAID LIQUID WHILE SAID LIQUID IS BEING PASSED BY SAID PUMPING FROM ABOVE SAID BED INTO THE BOTTOM OF SAID BED, AND THEN DISCARDING SAID LIQUID IN WHICH THE REMAINDER OF SAID MATTER IS SUSPENDED AND ENTRAINED PRIOR TO RESUMING THE USE OF SAID BED FOR FILTRATION.
INTE THE METHOD OF CLEANING BY BACKWASHING A LIQUID FILTER BED FORMED OF SOLID HARD PARTICLES HAVING A SPECIFIC GRAVITY APPRECIABLY GREATER THAN THAT OF THE MATTER REMOVED FROM THE LIQUID FILTERED THROUGH SAID BED, THE IMPROVEMENT WHICH COMPRISES INITIALLY RECYCLING THE LIQUID TO BE FILTERED UPWARDLY THROUGH SAID BED AS BACK WASHING LIQUID WHILE PASSING A GAS UPWARDLY THROUGH SAID BED, THE COMBINED FLOW OF SAID LIQUID AND SAID GAS BEING CONTROLLED TO CAUSE AT LEAST 25% EXPANSION OF THE SETTLED VOLUME OF SAID BED AND VIGOROUS RANDOM MOVEMENT OF SAID SOLID PARTICLES WITHOUT ENTRAINMENT OF SAID SOLID PARTICLES IN SAID LIQUID OF MATTER PREVIOUSLY DEPOSITED IN TRAINMENT IN SAID LIQUID OF MATTER PREVIOUSLY DEPOSITED IN SAID BED, SAID RECYCLING OF SAID LIQUID TOGETHER WITH SUSPENDED AND ENTRAINED MATTER BEING CONDUCTED BY PUMPING SAID LIQUID FROM ABOVE SAID BED INTO THE BOTTOM OF SAID BED, PARTIALLY REMOVING SAID SUSPENDED AND ENTRAINED MATTER FROM SAID LIQUID WHILE SAID LIQUID IS BEING PASSED BY SAID PUMPING FROM ABOVE SAID BED INTO THE BOTTOM OF SAID BED, AND THEN DISCARDING SAID LIQUID IN WHICH THE REMAINDER OF SAID MATTER IS SUSPENDED AND ENTRAINED PRIOR TO RESUMING THE USE OF SAID BED FOR FILTRATION.
Claim 2
Dependent Claim
201 words
INTE THE METHOD OF CLEANING BY BACKWASHING A LIQUID FILTER BED FORMED OF SOLID HARD PARTICLES HAVING A SPECIFIC GRAVITY APPRECIABLY GREATER THAN THAT OF THE MATTER REMOVED FROM THE LIQUID FILTERED THROUGH SAID BED, THE IMPROVEMENT WHICH COMPRISES INITIALLY RECYCLING THE LIQUID TO BE FILTERED UPWARDLY THROUGH SAID BED AS BACK WASHING LIQUID WHILE PASSING A GAS UPWARDLY THROUGH SAID BED, THE COMBINED FLOW OF SAID LIQUID AND SAID GAS BEING CONTROLLED TO CAUSE AT LEAST 25% EXPANSION OF THE SETTLED VOLUME OF SAID BED AND VIGOROUS RANDOM MOVEMENT OF SAID SOLID PARTICLES WITHOUT ENTRAINMENT OF SAID SOLID PARTICLES IN SAID LIQUID OF MATTER PREVIOUSLY DEPOSITED IN TRAINMENT IN SAID LIQUID OF MATTER PREVIOUSLY DEPOSITED IN SAID BED, SAID RECYCLING OF SAID LIQUID TOGETHER WITH SUSPENDED AND ENTRAINED MATTER BEING CONDUCTED BY PUMPING SAID LIQUID FROM ABOVE SAID BED INTO THE BOTTOM OF SAID BED, PARTIALLY REMOVING SAID SUSPENDED AND ENTRAINED MATTER FROM SAID LIQUID WHILE SAID LIQUID IS BEING PASSED BY SAID PUMPING FROM ABOVE SAID BED INTO THE BOTTOM OF SAID BED, AND THEN DISCARDING SAID LIQUID IN WHICH THE REMAINDER OF SAID MATTER IS SUSPENDED AND ENTRAINED PRIOR TO RESUMING THE USE OF SAID BED FOR FILTRATION.