David,

 

In addition to the information I already e-mailed below, Lakeside makes a screen (Raptor) very similar to the Huber RPPS fine screen (Lakeside actually used to distribute Huber screens in the US, but have parted ways and have been making similar screens for a while now).  As with the Huber RPPS screen, it would be a 2 mm perforated plate rotary drum screen in its own tank with integral washer/compacter.  Lakeside has a Raptor in Medical Lake, WA not far from Cheney and Spokane.  The Medical Lake WWTP is a 1 MGD facility producing reclaimed water using standard media filters.  If you contact City Hall at (509) 565-5000, I’m sure they’ll direct you to the correct contact at the WWTP.  Again, please let us know if you’d like for us to arrange a visit to any or all of these facilities.  I saw full scale units of both the Huber and Lakeside rotary drum screens at WEFTEC and they are similar in many ways.

 

 

David,

 

You’d asked for information on local installations of the fine screens we are recommending for consideration.  As you will recall, we recommend using rotary drum screens with perforated plates having 2 mm circular openings.  The two manufacturers we are giving consideration to are Huber and Parkson, both of which are well established in this technology.  Currently the fine screens are included as part of the MBR System Supplier’s scope of supply.  We considered both the Huber RPPS screen and Parkson Rotomesh Screen (see attached brochures).  The Huber RPPS screen is an in-channel type screen, but can be installed above grade in its own tank (look at pictures of this type of installation in the Rotomat Ro2 brochure).  The Rotomesh screen is self-contained for above grade installation.  The fine screen specification in the Membrane System RFQ/RFP package is based on the Huber RPPS screen.  We recommend this screen over the Parkson Rotomesh for a few reasons:

 

1)       Each RPPS screen has an integral washer compactor.  The Rotomesh requires a separate stand alone washer compactor unit, which requires additional screenings conveyors for more than one screen to share the same washer compactor unit.

2)       The footprint of the RPPS unit is a little smaller since the washer/compactors are integral with the screen and only one conveyor would be required to convey screenings from all of the screens to the dumpster.

3)       Budgetary cost information suggests that the RPPS screens and Rotomesh screens would cost about the same.  The budgetary cost of the RPPS is $210,000, or $630,000 for 3 screens (cost includes stainless steel tanks with covers).  The budgetary cost of the Rotomesh is $170,000 for each screen and $60,000 for each washer/compactor, which would be a total budgetary cost of $630,000 for 3 screens and two washer compactors (one backup).  These costs do not include screenings conveyors.

 

Huber has a Rotamat® Ro2 installation in Colville, WA (picture of installed unit attached).  This unit is basically identical to the proposed RPPS unit, only it uses a V-Wire screen rather than perforated plate.  Contact information is as follows:

 

Colville, WA  WWTP

Ralph Lane

Wastewater Treatment Plant Operator II

Or

Dennis Ferguson

Water/Sewer Superintendent

dennis@publicworks.ci.colville.wa.us

(509) 684-2244 (Main # for Water/Sewer Dept.)

 

Parkson has a Rotoshear unit installed in Cheney, WA.  The Rotoshear at Cheney is essentially the same as Rotomesh, but it uses wedgewire rather than perforated plate.  Contact information is as follows:

 

Cheney, WA  WWTP

Dan Ferguson

Treatment Plant Operator III

(509) 498-9293 (Office # for Public Works)

dferguson@cityofcheney.org

 

Unfortunately, neither of these installations are close.  It would be a very long day of driving to visit both.  You may want to call each first and discuss the installation with them.  If after doing that you are still interested in visiting one or both, I can setup site visits with the vendors.  We could probably visit both in one day if we flew to Spokane and rented a car.  Colville is about 1.5 hours north of Spokane and Cheney is about 20 minutes south of Spokane.

 

Tom Giese, P.E.

Kennedy/Jenks Consultants

32001 32nd Ave. S, Suite 100

Federal Way, WA  98001

(253) 874-0555

Direct: (253) 942-3402

Fax:  (253) 952-3435