Appeal No. 97-2914
Application No. 08/448,060
The fact remains, however, that none of the prior art references or Aadmission@ cited by the examiner,
individually or in combination, teach or suggest the means for injecting dry sorbent particles into the flue
gas after particulate collection and before wet scrubbing, so that some of the dry sorbent particles react
with and remove substantially all the SO3 in the flue gas, followed downstream by the means for
conveying the
substantially SO3-free gas, reacted dry sorbent, and unreacted dry sorbent particles to a wet scrubber
means in which the unreacted dry sorbent is available as a wet reagent to remove SO2 from the
substantially SO3-free flue gas during wet scrubbing.
Both Cyran and Steag teach dry cleaning or sorbent means, but both also teach removal of the
particles downstream with filters. The examiner argues that the present claims have the term
Acomprising@ which does not exclude the filter of Cyran or Steag. Nevertheless, the presence of a filter
would undermine the requirement in the claimed invention that the unreacted dry sorbent particles are
conveyed into the wet scrubber means to produce a wet reagent for removing SO2. The examiner has
provided no other evidence suggesting to one of ordinary skill in the art a modification of the prior art so
that the dry sorbent passes into the wet scrubber means as required in the presently claimed process.
Without such evidence, the prima facie determination of obviousness for the claimed invention as a
whole cannot stand. See In re Dembiczak, 175 F.3d 994, 1000, 50 USPQ 2d 1614, 1618 (Fed. Cir.
1999).
The prior art cited by the examiner can be seen as Ateaching away@ from the presently claimed
invention on this point. As discussed above, both Cyran and Steag teach the interception of particles
downstream from the dry cleaning or sorbent step with a filter. Interception suggests that the sorbent
particles have no other use, which Ateaches away@ from the downstream use of those particles. As
10
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 Next
Last modified: November 3, 2007