John D. Simmons

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Drexel Hill, PA, US

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Patents Grantslast 30 patents

Information Patent Grant
Methods and apparatus for monitoring a filter bed by differential p...
- Patent number 6,159,384
- Issue date Dec 12, 2000
- RG, Delaware, Inc.
- R. Lee Roberts
- C02 - TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
Information Patent Grant
Methods and apparatus for monitoring a filter bed by differential p...
- Patent number 5,980,755
- Issue date Nov 9, 1999
- RG, Delaware, Inc.
- R. Lee Roberts
- C02 - TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE