Overview of Heat Recovery Boiler Systems and Operating Costs Factors Effecting Blowdown Blowdown Heat Recovery The Energy Tank

Transcription

1 Overview of Heat Recovery Boiler Systems and Operating Costs Factors Effecting Blowdown Blowdown Heat Recovery The Energy Tank

2 Unbiased, Third-Party, Water & Energy Management Consulting Firm: - Not affiliated with any equipment or chemical suppliers. - Provide clients with sound technical advice and recommendations to effectively manage and reduce their Operating Costs. - Provide Root Cause Failure Analysis of Failed equipment or processes not performing to Design Criteria Years Industrial Water Treatment back-ground Years conducting Energy Audits and working with clients on recycle / 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 projects designed to reduce system operating costs.

3 Generalized Industry Overview Of Boiler Plant Costs Flue Gas: Direct Loss $ Steam: Direct Loss $ Cost to Process $ Fuel: Direct Cost $ Water: Boiler(s) Direct Cost $

4 Simplified Boiler Plant Operating Cost Steam to heat Boiler Feedwater $+++ As viewed by Capture H2O Flue $ Fuel $ Boiler(s) Condensate $ Treated Water / Energy Steam $+++ Traps Vent $ Vent $ City Water $ Regen. or Power $ Waste $ Treated Water $+ Boiler Feedwater $++ Treated Water / Chemicals / Steam Blowdown $ City Water $ Typically between 1 20% of Steam Load. Effected by Treated Water Combination of Large Bottom and Small Surface Blowdown Energy / Water / Chemicals

5 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.

6 How the Patented BHR Process Saves Steam to Feedwater Reduced $+++ Canada Patent No.: 2,414,611 USA Patent No.: 6,938,583 Flue $ Fuel $ Boiler(s) Steam $+++ City Water $ Boiler Feedwater $++ Vent $ Flash Steam Recovered to steam going to Feedwater Treated Water $+ Hot Make-up less steam needed to heat feedwater Cold Make-up Blowdown $ Typically between 1 20% of Steam Load Cooled by Treated Cold Make-up Water City water cooling eliminated

7 The Patented BHR Process 1) 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.

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9 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.

10 Standard Blowdown Tank Standard Blowdown Plus Continuous Blowdown Heat Recovery BHR Process With "The Energy Tank" tm $5,000 - $12,000 $12,000 - $30,000 $5,000 - $40,000 Depressurizes all blowdown streams Releases steam to atmosphere Consumes city water to cool blowdown Need to replace every yrs Depressurizes manual/bottom blowdown Recovers some flash steam to Feedwater/deaerator Consumes city water to cool bottom blowdown and some continuous blowdown Hit and Miss process due to intermittent flows of blowdown or make-up Needs a Level Control Device to maintain level in Flash Pot (valve or steam trap) Thermal stress (hot/cold) on heat exchanger due to intermittent flow Need to repair/replace components every months Depressurizes ALL blowdown streams No flash steam lost to atmosphere No Hit or Miss due to large storage section residence time No mechanical equipment to maintain / monitor / fail No additional space required. Fits in same space as standard blowdown tank Does Not consume city water to cool blowdown streams Heat Exchanger protected from thermal stresses Need to replace every yrs

11 P PRV Station to reduce Steam to less than 7 psig going to deaerator Steam to users Deaerator 5-7 psig BHR-XXHM Flash Steam outlet line feeding to down-steam side of PRV, c/w check valve to prevent backfeeding to BHR-XXHM Boiler Feedwater 4-inch Atmopshere Vent Line Heated Softened Make-up to Deaerator Blowdown (Timed & Intermittent) To Flash Chamber on BHR-250HM Cold Softened Make-up to BHR-XXHM BHR-XXHM "Energy Tank" Cold Blowdown Water to Sewer Typical Installation of BHR-XXHM "Energy Tank" Utilities Optimized 6399 Olde Drive, Appin, Ontario N0L - 1A0 P/F: C:

12 Typical The Energy Tank tm Internals Steam Muffler Loop Drain

13 Already Have Continuous Blowdown Heat Recovery? Here s what you are missing from a 1 ½-inch Manual Bottom Blowdown! 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 Water Savings, CM City water eliminated at blowdown tank >$50,600 >202,000 CM >10,000 CM >$10,000 >$16,000 >64,000 CM >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

14 How GREEN are your BLUE Numbers? BHR Energy Calculation available at PLANT LOCATION: Food Plant in Toronto Boiler Horsepower: 400 BHP Projected Load: 85 % Efficiency (Fuel to Steam) 70 % Cycles of Concentration: 15 Cycles Steam Pressure: 100 psig Steam Temperature: 338 Deg. F Sensible Heat at Steam Pressure: 309 BTU/# Make-up Water Temperature: 60 Deg. F Projected Make-up Temperature: 100 Deg. F Percent Condensate Returns: 85 % of Steam Flow Condensate Temperature: 160 Deg. F Hours of Operation per Day: 24 Hours Days Operation per Week: 5 Days Cost of Gas: $ $/CM

15 How GREEN are your BLUE Numbers? BHR Energy Calculation available at Calculated Steam Load: Calculated Blowdown Losses: Total Boiler Feedwater Flow: Flash Steam Potential: Flash Steam From Blowdown: Flash Energy Available: Energy to Heat Condensate to Steam Temp.: Energy to Heat Make-up to Steam Temp.: Projected Energy to Heat Make-up: Energy to Heat Boiler Feedwater - Existing: Energy to Heat Boiler Feedwater - Projected: Energy Saved: Equivalent Gas Saved: Daily Savings: Annual Savings: #/Hr #/Hr #/Hr 11.4 % to 7 psig dea #/Hr BTU/Hr BTU/Hr BTU/Hr BTU/Hr BTU/Hr BTU/Hr BTU/Day CM/Day $68.33 $/Day $17, $/Year

16 CASE STUDY Major Pharmaceutical Company, NJ USA

17 Installation Detail

18 Pharmaceutical Plant, NJ Test Data (August Minute Time Stamps) Temperature (Deg. F) Blowdown Heat Recovery Process - Temperature Evaluation One Minute Time Stamp Intervals from Externally Mounted Thermocouples 2 x CB-300HP Boilers / Manual and Conductivity Controlled Blowdown Flash Steam and Make-up Outlet Temperatures Time in Minutes (August 1st - 31th, 2009) Red Line = Flash Steam Outlet Temperature Thermocouple on outside of piping. Temperatures above 212F confirm steam flow to heat pipe above atmospheric steam temperature. Temperature (Deg. F) Flash Steam and Make-up Outlet Temperatures August 1st Time (Minutes) Blue Line = Make-up Outlet Temperature Thermocouple on outside of piping. Wavy lines represent on/off flow and changing velocity.

19 Energy Tank Project Project Cost: $46,500 Savings: $24,000/yr Funding Source: CPA Time to Implement: 3 Months From CPA Approval