Figure I Generalized map of the Wilbur Mining ... - University of Utah

case of chariging exchanger-surface area to accommodate
changes in flow and temperature conditions by
adding or removing plates.
For instance in this application, as individual
buildings eome on line, plates could be
added. Since the plates are in parallel, flow is
increased while pressure drops reraain the same and
inlet and outlet temperatures reraain the same.
Small changes in/seeondary loop inlet temperature
(or priraary for that.matter.) can-be accommodated by
adding or reim.ving plates and still maintairi outlet'temperature.
Where-large secondary inlet water
temperature changes are raaae (for instance, if
all buildings changed from a 40°F T to 6d°F T) it
may be necessary to series portions of the exr
ehanger. This can be accomplished with external
pluratiing while using the same exchanger plates arid
adding, a blocking plate between the" seried sections.
Design Recommendations. For the initial 14building
district 2 plate-type heat, exchangers are
arranged in parallel with automatic controls to
stage the flow in both the pumps and exchangers.
Thus, loads' up to 50i of peak will be handled by
one pump and exchanger,, reducing pum"pihg costs and
provi di rig maintenance time. One unit, will prpvide'
the heat required approximately 65% of the' time
during the Klamath Fa-lls heating_ season.
The exchangers will be selected to operate at
the mini [iiura flows required fpr domes tic, water heating
during surmer months arid also allow the, addition
of plate's to handle inc'reased loads while
maintaining inlet-and ,outlet temperatures as the
district is expanded.
plate heat exchanger general s'pecif icati ons:
Type - Single pass with 150
• 316, sst plates EPDM gaskets
Size - 9'3" long x 1'7" y/ide x 5' high
makirtium platage
Geothermal side - 219°F Tnlet
175°F Outlet
4.3 psig pressure drop
(1,000 gpm maximum
flow with full
platage.)
350: gprii flow
Secondary "side - eOQ^F Outlet
160°F Inlet
3.7 ps.ig pressure ;idrop
(1,000 gpra raaximum
flbw.wi'th full
piatage)
376 gf)m flow
Cost - .$14,000 ea. - 2'required
Life of the '316 sst plates is expected to be 30
years qr more in the Klamath Falls geothermal waters...
Gasket life, is expec.ted to ,be 5 years v/ith'
frequent cleaning, and gasket cost is $41 each-
The unit tan be disassembled for .cleaning and reassembled
in 4 hours by 2 riieri. Additional plates
for future expansion cost, $80 each including, gaskets."
Estimated maintenaricl costs—5 years--
$6,340.
389
Pumps
Lund, et. al.
Production Well -Puraps. The productipn well
pujiips are vertical turbine v/ith variable speed
fluid drive. The variable ispeed drive provides
for coritinuous. operation of the pumps to provi die
constant pressureat the well head and in the supply
iirie urider varying flow requireraents. Pump
discharge pressure is monitored by the fluid coup-
Itng control which changes turbine shaft speed to
mairitain constant discharge pressure Troin rio-flow
to full-flow conditions and eTiiiii nates the need
for stoi'age tanks required with iritermittent,pump'
operation. The turbine shaft is always rotating
proyiding lubrication for reduced bearing and.
shaft wear, the drives have proven successful in
the Oregon rrfstitute of Technology and Presbyterian
Intercommunity Hospital systeras; v/here it is estimated
that bearing, sKaft, and raotor li-fie have-been
doubled.
-Vertical turbine-pumps are selected by choosing
the most economical combination of pulrif bov/1
arid nuraber of stages that will produce the.desired
pressure and flow rates,. Attention must be giveri
to efficiency arid'where variable speeds are a r^equiferaent,
the pump curve should be ,as flat as possible
to maintain high overall wire-to-water
efficiency.
Well Head Pumps.
Vertical turbine witli variable . ;peed drive:
.Rated flow at 1750 RPM
500 gpm
Column length
350 ft
Golumn diameter
Sowl diameter
8 in
9 3/4. iri
Shaft diameter.
1 1/2 in
Number of bov/ls
11
Discharge' p'ressure
20 psi
Motor (electric)
Drive - torque, converter type
2i,slip at full load.
75 hp
Rated Capacity
75 hp
Wire-to-water efficiency
Current cost
72%
$41 ,-488
'Number requi red .
Estiraated maintenance costs;:
2 ea
Change packing .S-lubricate, 6- mo.
interval
Pull pump', inspect S replace
$29
bearirigs, 3-year iritervals
Overhaul variable speed drive,
$4,000
5-year interval
$580
Ih.i'ection Pump. Since the museum well has
been selected as the injection site, and since the.
well is; a flowing artesian v/ell,, an inj.ection pump
will be required. It is assumed that injection
pressures foir a goOd producing well, are .approxiriately
equal to the drawdown pressures plus any artesian-pressure
when that well is used for injection.
This has been experienced at Raft River arid
in Klaraath Falls. Additional pumping pressure of
ab_qut ;25% is recommended to account for the difference
in temperature when irijectiori temperatures are
Ipwer than pr'oduction temperatures, gradual fouling