Document ID: EPA-HQ-OW-2008-0667-3543
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2014-08-15T04:00Z

316B RULE

 TELEPHONE LOG

Name of Caller: 	John Sunda, SAIC

Date: 	January 15, 2010

Company Name: 	SPX Cooling Technologies, Inc.

Street Address:	7401 W 129 Street

City/State/ZIP:	Overland Park, KS 66213

Person Contacted:	Kent A. Martens, P. E.

Title:	Chief Technical Advisor - Evaporative Cooling	

Contact Info:	Tel:      913/664-7501

	Fax:     913/693-9522

	Cell:     913/302-7234

	kent.martens@spx.com	

Questions:  Inquired about plume and noise abatement cooling towers
including questions about operating problems cited by others with the
plume abated towers at Newington Energy Facility

The Newington plume abatement cooling tower is an obsolete cooling tower
design called “Clear Flow” that they no longer sell.  The dry
cooling portion of this design used corrugated PVC sheets with air and
water flowing between alternating sheets. He was not sure of the problem
but thinks it involved some leaking of cooling water in this part of the
system. This design of corrugated PVC sheets and alternating flow is
somewhat similar in design to their new Clear Skies technology but in
this case the alternating flow is ambient air and wet cooling exhaust.
This technology was originally designed as a water conservation
technology but has demonstrated an ability to function as plume
abatement as well.  He agreed that it may take some time for this
technology to acquire more public acceptance.  They have performed a
successful full scale demonstration in New Mexico.

Regardless, they do have plume abatement towers that use conventional
coils that are suitable for saltwater applications. He suggested they
would need to be constructed using high grade stainless steel or
titanium.

I asked about cycles of concentration for saltwater systems and he said
that typically they operate in the range of 1.3 to 1.7. I mentioned that
the Newington NPDES permit fact sheet indicated that the tower could
operate at a COC of 2.0 and he said that 2.0 was possible but it was
pushing the limit.  

Regarding increased energy usage for plume abatement – although the
dry coils are higher than the wet tower spray nozzles, once the system
fills up with water the head loss is primarily due to friction losses
and the increase in pumping head will range from 5 to 10 ft with 8 ft
being a typical value.  There will also be a slight fan energy increase
on the order of about 5 to 10%.  This is due to the fact that the system
needs to account for some damper air leakage. Dampers are used to close
off the dry cooling coil portion in winter when it is not needed.   He
said that an increase in capital costs for a plume abated tower of 2.5
to 3.5 can be expected.  

Regarding the ability to use plume abatement in back-to-back
configurations, it isn’t that it can’t be done but rather that since
the coils must be placed in a vertical configuration, it is difficult to
get full mixing of the dry cooling airflow coming in on one side with
the wet cooling airflow. So you don’t get sufficient dryer airflow
mixing towards the back side resulting in partial plume abatement (i.e.
only front half of plume is fully abated).

Regarding noise attenuation, he though that a 10% increase in capital
costs might be low especially if the noise abatement requirements are
aggressive. I suggested an aggressive design target of 50 dBA at 500 ft.
He did a quick calculation of an 18 cell back-to-back tower showing the
non-abated design producing 63.3 dBA at 500 ft and the same abated tower
producing 47 dBA at 500 ft using numerous additional features resulting
in nearly double the cost of the towers.  I requested that he provide me
with some design and cost estimates for comparable towers with different
features including aggressive noise abatement, moderate noise, and plume
abatement. 

Some noise abatement points he made:

Noise abatement requires a sophisticated analysis by a specialist.  

Some of the additional technologies may only be necessary on one side of
the tower limiting costs.

Low noise fans can cost orders of magnitude more than conventional fans

Barrier walls work well for close up receptors but not as well for far
off receptors

They have an array of technologies such as splash baffle, inlet and
outlet attenuators, aluminum frame baffles, etc.

Follow-up on May 5, 2010

Inquired about degree of increase in O&M costs for plume abatement. I
said that my calculations showed a total fan & pump power increase of
about 15% and he said that would be a reasonable estimate. I noted that
our cooling tower and basin capital costs were about $80/gpm. He said
that his quick calculation was $40/gpm but if you included installation,
controls, mechanical & electrical equipment that this figure was
reasonable. I then noted that using a factor of 2.5 resulted in a
capital cost increase of $200/gpm for plume abatement.. 

I then noted that O&M costs for conventional towers was often cited as
1%-2% and that our EPA cost estimate includes about $1.25/gpm (about
1.5% of $80) for non-power maintenance and another $1.25 for chemicals
to operate at high COC.  He said that there would also be an increase in
non-power O&M costs due to the larger tower and maintenance of coils and
dampers. He said a 50% to 100% increase in the non-power O&M over that
for the conventional tower would be reasonable.