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Flow indicator for filter apparatus
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Slurry feeder
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Filter underdrain
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Water-treating process and apparatus
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Removal of manganese from water
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Method and apparatus for treating water
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Water purifying apparatus
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Iron removal apparatus
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Method and apparatus for treating water
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Water softening
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Automatic backwash filter control
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Aeration of treated water in elevated tanks
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Machine for making concrete blocks
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Method for installing well strainers
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Well casing and strainer
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Concrete well strainer
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Water aeration in tanks
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