PTAB

IPR2019-01582

EnerCorp Sand Solutions Inc v. Specialized deSanders Inc

Key Events

Petition

petition

Title: Desanding Apparatus and a Method of Using Same
Brief Description: The ’921 patent discloses an apparatus for removing particulates, such as sand, from multiphase fluid streams common in oil and gas production. The invention utilizes a vessel with an internal, generally upright spiral plate baffle that receives an incoming fluid stream, directs it along an elongated horizontal path to promote separation, and allows particulates and liquids to fall under gravity while desanded gas exits from a central outlet.

Prior Art Relied Upon: Al-Alusi (Application # 2009/0314161).
Core Argument for this Ground:
- Prior Art Mapping: Petitioner argued that Al-Alusi, which discloses a cyclone separator for removing contaminants from an aircraft’s airstream, teaches every element of the challenged claims. Al-Alusi’s separator vessel (102) includes a tangential fluid inlet (204), a central outlet conduit (200, 202), and an internal spiral plate (212). Petitioner asserted this plate is "generally upright," is located below the vessel top, receives the fluid stream, and directs it along an elongated, generally horizontal path. The plate has an open top above the fluid inlet and an open bottom through which particulates fall. The intake for the outlet conduit is located in a central portion of the baffle and below its open top. For dependent claims, Petitioner contended Al-Alusi’s description of the spiral plate’s dimensions inherently forms an Archimedean spiral (claim 2) and that its conical lower section is an inclined side wall facilitating particulate migration to a drain (claims 8-9).

Prior Art Relied Upon: Al-Alusi (Application # 2009/0314161).
Core Argument for this Ground:
- Prior Art Mapping: Petitioner argued that to the extent Al-Alusi does not explicitly anticipate every limitation, any differences would have been obvious modifications. This includes modifying the separator head shape (claims 14-16) which is a routine design choice, and ensuring the inclined wall slope exceeds the angle of repose for particulates (claim 10) which is a fundamental requirement for gravity-based solids handling.
- Motivation to Combine (or Modify): A Person of Ordinary Skill in the Art (POSITA) would have been motivated to adapt Al-Alusi's separator for oil and gas desanding. Al-Alusi states its technology can be applied to "other systems." To avoid the continuous loss of valuable hydrocarbons from the drain (weep hole 208), a POSITA would modify the system for batch operation by restricting the drain. This would necessarily cause liquids to accumulate, forming a gas/liquid "freeboard interface" at the level of the gas outlet intake, as recited in the claims.
- Expectation of Success: A POSITA would have a high expectation of success in adapting Al-Alusi. Cyclone separation is a well-understood, predictable technology. Al-Alusi itself teaches using computational fluid dynamics (CFD) to determine the appropriate dimensions for maximizing collection efficiency in any given application, demonstrating that such modifications were routine.

Prior Art Relied Upon: Al-Alusi (Application # 2009/0314161) and Cauley (Patent 7,641,770).
Core Argument for this Ground:
- Prior Art Mapping: This ground addresses claim 11, which recites a specific drain configuration comprising an inlet valve, a particulate accumulation chamber, and a discharge valve. Petitioner argued Al-Alusi provides the base separator vessel with a drain, while Cauley teaches a standard "double-dump valve" used for handling bulk materials like tar sands. Cauley's valve inherently includes an inlet gate (valve 36), an intermediate chamber, and an outlet gate (valve 38).
- Motivation to Combine: A POSITA motivated to modify Al-Alusi for batch operation (as argued in Ground 2) would seek a known method for removing collected solids from a pressurized vessel without shutdown. Cauley's double-dump valve is an analogous, standard solution for this exact problem. A POSITA would combine Cauley's valve with Al-Alusi's drain outlet to achieve safe and efficient batch removal of sand while maintaining system pressure.
- Expectation of Success: The combination involves attaching a standard, off-the-shelf component to a standard outlet port using known techniques. Each element performs its expected function, making the result of the combination entirely predictable.

"freeboard interface": Petitioner argued this term has a dual meaning based on the specification. If liquids are present in the fluid stream, the term means the gas/liquid interface (liquid level). If no liquids are present, it is the highest elevation to which particulates can accumulate before the separator fails, which is determined by the intake opening of the outlet conduit.
"generally upright spiral plate baffle": Relying on prosecution history where the applicant distinguished the Greve reference, Petitioner contended this term requires a plate-like spiral oriented to "check, impede, and obstruct" the incoming, generally horizontal fluid stream. This construction distinguishes the claimed baffle from a simple horizontal ramp or raceway that does not obstruct the primary gas flow.

Petitioner argued that discretionary denial under 35 U.S.C. §325(d) would be inappropriate because the asserted grounds are not the same as or substantially similar to those previously presented to the USPTO. The primary reference, Al-Alusi, was never cited or considered during examination. Petitioner asserted Al-Alusi is materially different from the examination references (Milia and Greve), as it teaches key features—such as a spiral baffle with an open top and an outlet conduit intake descending below that top—that the patent owner previously used to distinguish the prior art. Consequently, the petition raises new issues of patentability not previously considered by the examiner.

Petitioner requested the institution of an inter partes review and the cancellation of claims 1-16 of the ’921 patent as unpatentable.