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• Overview of Heat Recovery• Boiler Systems and Operating Costs• Factors Effecting Blowdown• Blowdown Heat Recovery “The Energy Tank”
• Unbiased, Third-Party, Water & Energy Management Consulting Firm :
- Not affiliated with any equipment or chemical suppliers.
- Provide clients with sound technical advice and recommendationsto effectively manage and reduce their Operating Costs.
- Provide Root Cause Failure Analysis of Failed equipment orprocesses not performing to Design Criteria.
- 15 Years Industrial Water Treatment back-ground.
- 12 Years conducting Energy Audits and working with clients onrecycle / reuse projects.
- Use Utility Mapping Process to systematically define all operating costs in Steam / Hot Water / Process Cooling applications.
- Defined costs can be used to identify cost effective projectsdesigned to reduce system operating costs.
Generalized Industry Overview
Of Boiler Plant Costs
Boiler(s)Fuel:
Direct Cost $
Water:
Direct Cost $
Flue Gas:
Direct Loss $ Steam:
Direct Loss $
Cost to Process $
Simplified Boiler Plant Operating CostAs viewed by Capture H2O
City Water $
Regen. or Power $
Waste $Treated Water $+
Boiler Feedwater$++ Treated Water / Chemicals / Steam
Boiler(s)Fuel $
Flue $
Vent $
Blowdown $Typically between 1 – 20% of Steam Load. Effected by Treated Water
Combination of Large Bottom and Small Surface Blowdown
Energy / Water / Chemicals
City Water $
Steam $+++
Traps
Condensate $
Treated Water / Energy
Vent $
Steam to heat Boiler Feedwater
$+++
BLOWDOWN HEAT RECOVERY (BHR)Patented Process: Canada No.: 2,414,611 USA No.: 6,938,583
“THE ENERGY TANK ”Trade Name Registered
Blowdown from steam boilers is a necessary function. This function however releases significant energy from the
Steam Generation Process.
The BHR process effectively recovers essentially all this energy and routes it back to the boiler feedwater system.
This simplified process reduces Fuel Consumption, Greenhouse Gas Emissions and Water Usage.
How the Patented BHR Process Saves
City Water $
Treated Water $+
Boiler Feedwater$++
Boiler(s)Fuel $
Flue $
Blowdown $
Typically between 1 – 20% of Steam Load
Cooled by Treated Cold Make-up Water
City water cooling eliminated
Steam $+++
Vent $Flash SteamRecovered to steam going to Feedwater
Cold Make-up
Hot Make-up – less steam needed to heat feedwater
Steam to FeedwaterReduced$+++
Canada Patent No.: 2,414,611 USA Patent No.: 6,9 38,583
The Patented BHR Process1) Flash Steam generated due to pressure drop is recovered to
Low Pressure Steam System (steam going to deaerator) or Atmospheric Water Tank (vented feedwater tank or condensate receiver).
2) Large Storage section allows for retention time of remaining blowdown volume for heat recovery to make-up. Make-up passed through series of stainless steel coils to recover sensible heat in the hot blowdown water.
3) Due to cooling blowdown water with the make-up, the need for cooling with City Water before the drain is eliminated.
How is it Different / Better??1. Simplified straight-forward approach with no moving parts. “The Energy Tank” tm
serves as you Boiler Room blowdown/blow-off vessel.A BHR Energy Tank will pay for itself in less than 1 year compared to the 100% non-recoverable cost of a replacement blowdown tank!
2. Captures 100% of all blowdown streams– Large Bottom blowdown, Intermittent Surface Skim, Level Column blowdown all recovered. Any other process can only recover Intermittent/Continuous Surface Skim due to size/pressure rating limitations.
3. Due to large “Storage Section” capacity/retention time, “Hit and Miss” potential of typical Continuous Blowdown Heat Recovery processes is eliminated. Thermal stresses, “flash steam hot” to “make-up cold”, realized in Continuous Blowdown Heat Exchanger is eliminated – prolonging life expectancy of heat exchanger.
4. Any repairs or maintenance can be done on-site / in-situ with nothing more than a set of wrenches. Entire heat exchanger coil system can be removed and re-installed in a couple of hours.
StandardBlowdown
Tank
Standard BlowdownPlus
Continuous Blowdown Heat Recovery
BHR ProcessWith
"The Energy Tank" tm
$5,000 - $12,000 $12,000 - $30,000 $5,000 - $40,000
Depressurizes all blowdown streams
Depressurizes manual/bottom blowdown
Depressurizes ALL blowdownstreams
Releases steam to atmosphere
Recovers some flash steam to Feedwater/deaerator
No flash steam lost to atmosphere
Consumes city water to cool blowdown
Consumes city water to cool bottomblowdown and some
continuous blowdown
No “Hit or Miss” due to large storage section
residence time
Need to replace every 20 – 30 yrs
“Hit and Miss” process due to intermittent flows of blowdown
or make-up
No mechanical equipmentto maintain / monitor / fail
Needs a Level Control Device to maintain level in Flash Pot
(valve or steam trap)
No additional space required.Fits in same space as standard
blowdown tank
Thermal stress (hot/cold) on heat exchanger due to
intermittent flow
Does Notconsume city waterto cool blowdown streams
Need to repair/replace componentsevery 12 – 24 months
Heat Exchanger protected from thermal stresses
Need to replace every 20 – 30 yrs
UtilitiesOptimized
6399 Olde Drive, Appin, Ontario N0L - 1A0P/F: 519-289-5246 C: 519-668-8714
P
BHR-XXHM "Energy Tank"
Cold Blowdown Water to Sewer
Cold Softened Make-up toBHR-XXHM
Heated Softened Make-up to Deaerator
4-inch Atmopshere Vent Line
Blowdown (Timed & Intermittent)To Flash Chamber on BHR-250HM
PRV Station to reduceSteam to less than 7 psig going to deaerator
BHR-XXHM Flash Steamoutlet line feeding to down-steamside of PRV, c/w check valveto prevent backfeeding toBHR-XXHM
Boiler Feedwater
Steam to users
Typical Installation of BHR-XXHM "Energy Tank"
Deaerator5 - 7 psig
Typical “The Energy Tank” tm Internals
Steam Muffler
Loop Drain
BLOWDOWN HEAT RECOVERY – ADDITIONAL SAVINGS OPPORTUNITY Average Load
No Heat Recovery Average Load
CBD Heat Recovery Steam Load, #/Hr 70,000 Blowdown Load, #/Hr 3,500 1,150 Gas Savings, $ / CM Based on $0.25/CM Gas Cost
>$50,600
>202,000 CM
>$16,000
>64,000 CM Water Savings, CM City water eliminated at blowdown tank
>10,000 CM
>$10,000
>4,600 CM
>$4,600 Environmental Savings Tons Carbon Dioxide gas emissions
>425 Tons
>134 Tons
NET SAVINGS : GAS: >64,000 CM $16,000 ABOVE CURRENT SAVINGS EMISSIONS: >134 TONS OF CARBON DIOXIDE GAS WATER : >4,600 CM CITY WATER >$4,600
Already Have Continuous BlowdownHeat Recovery?
Here’s what you are missing from a 1 ½-inch Manual Bottom Blowdown!
PLANT LOCATION: Food Plant in Toronto
Boiler Horsepower: 400 BHPProjected Load: 85 %Efficiency (Fuel to Steam) 70 %Cycles of Concentration: 15 CyclesSteam Pressure: 100 psigSteam Temperature: 338 Deg. FSensible Heat at Steam Pressure: 309 BTU/#Make-up Water Temperature: 60 Deg. FProjected Make-up Temperature: 100 Deg. FPercent Condensate Returns: 85 % of Steam FlowCondensate Temperature: 160 Deg. FHours of Operation per Day: 24 HoursDays Operation per Week: 5 DaysCost of Gas: $0.3500 $/CM
How GREEN are your BLUE Numbers?BHR Energy Calculation available at
www.blowdownheatrecovery.com
Calculated Steam Load: 11730 #/HrCalculated Blowdown Losses: 782.0 #/HrTotal Boiler Feedwater Flow: 12512 #/HrFlash Steam Potential: 11.4 % to 7 psig dea.Flash Steam From Blowdown: 89.1 #/HrFlash Energy Available: 102428.1 BTU/HrEnergy to Heat Condensate to Steam Temp.: 1774749.0 BTU/HrEnergy to Heat Make-up to Steam Temp.: 706537.0 BTU/HrProjected Energy to Heat Make-up: 604877.0 BTU/HrEnergy to Heat Boiler Feedwater - Existing: 2481286.0 BTU/HrEnergy to Heat Boiler Feedwater - Projected: 2277197.9 BTU/HrEnergy Saved: 6997306.6BTU/DayEquivalent Gas Saved: 195.2CM/DayDaily Savings: $68.33 $/DayAnnual Savings: $17,766.60$/Year
How GREEN are your BLUE Numbers?BHR Energy Calculation available at
www.blowdownheatrecovery.com
CASE STUDY
Major Pharmaceutical Company, NJ USA
Installation Detail
Pharmaceutical Plant, NJ – Test Data (August 2009 – 1 Minute Time Stamps)
One Minute Time Stamp Intervals from Externally Mounted Thermocouples2 x CB-300HP Boilers / Manual and Conductivity Controlled Blowdown
Blowdown Heat Recovery Process - Temperature Evaluation
Flash Steam and Make-up Outlet Temperatures
50
100
150
200
250
300
1 1285 2569 3853 5137 6421 7705 8989 10273 11557 12841 14125 15409 16693 17977 19261 20545 21829 23113 24397 25681 26965 28249 29533 30817
Time in Minutes (August 1st - 31th, 2009)
Tem
pera
ture
(D
eg. F
)
Flash Steam and Make-up Outlet Temperatures August 1st
50
100
150
200
250
300
1 42 83 124 165 206 247 288 329 370 411 452 493 534 575 616 657 698 739 780 821 862 903 944 985 1026 1067 1108 1149 1190 1231
Time (Minutes)
Tem
pera
ture
(D
eg. F
)
Blue Line = Make-up Outlet TemperatureThermocouple on outside of piping.Wavy lines represent on/off flow and changing velocity.
Red Line = Flash Steam Outlet TemperatureThermocouple on outside of piping. Temperatures above 212F confirm steam flow to heat pipe above atmospheric steam temperature.
• Project Cost: $46,500
• Savings: $24,000/yr• Funding Source: CPA
• Time to Implement: 3 Months From CPA Approval
“Energy Tank” Project