maintenance shows of america april 2010 tampa florida presented by: byron nichols representing: the...

BOILER ROOM SHEETS:INTERPRETING THE

RECORDS

Maintenance Shows of AmericaApril 2010

Tampa Florida

Presented By: Byron Nichols

Representing: The American Society of Power Engineers

The Basic Log Book should record such readings as:

System Pressures System Temperatures Fuel Meter Readings Fuel Inventory Water Test Results Chemical additions

How should these readings be recorded?

As often as necessary to insure the safe and efficient operation of the system. This can be a little a once per day, twice per day, or once every hour.

With few exceptions the more reading taken give better data and can indicated system upset which can be missed using less frequent inspection methods.

Reading should be taken at the same time of day.

How do we record system variables:

Reading are recorded in written form.

Readings are logged using computer programs.

The First Step: Do the numbers make sense?

A basic understanding of the relationships of the operating principles of boilers and unit conversions will help to identify false or grossly inaccurate data.

Let’s look at a few examples:

Boiler Room Log Sheet #1 Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8Boiler Load (lbs/hr) 42,000 39,000 41,000 45,000 47,000 43,000 37,000 35,000Boiler (PSI) 100 99 100 100 99 100 101 100FW (PSI) 150 151 149 151 150 150 148 150D/A (PSI) 7 7 7 8 7 7 8 8Fuel Oil Pump (PSI) 150 150 151 150 149 150 150 151Boiler Burner Oil (PSI) 42 39 41 45 47 43 37 35Furnance Pressure (inH2O) 3.2 2.9 3.1 3.5 3.7 3.3 3.7 2.5Boiler Steam Total (Lbs) 960,000 831,000 942,000 998,000 1,032,000 1,008,000 1,001,000 798,000Boiler Oil Used (Gal) 9,200 7,890 9,029 9,565 9,891 9,661 9,594 7,591Lbs steam/Gal oil used 104 105 104 104 104 104 104 105Make-Up Water Total (Gal) 23,132 20,024 22,650 21,643 23,624 24,289 26,533 19,229Outside (°F) 30 31 29 28 26 29 33 34Boiler Stack (°F) 458 450 452 460 462 455 450 448Return Condensate (°F) 160 162 168 170 173 171 165 164D/A Tank (°F) 230 231 230 232 230 230 230 230Boiler Cond (micromho) 2800 2700 2800 2900 3000 2700 2800 2900Boiler M-Alk (ppm) 320 300 340 320 300 290 300 290Boiler Sulfite (ppm) 30 32 34 36 30 28 30 32Boiler Phosphate (ppm) 40 42 41 38 39 40 39 40Condensate Cond (micromho) 20 22 26 28 22 22 24 26Condensate pH 8.6 8.7 8.5 8.8 8.7 8.8 8.7 8.6Condensate Hardness (ppm) 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1Make-Up Cond (micromho) 100 120 110 110 110 100 120 110Make-up Hardness (ppm) 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1Feedwater Cond (micromho) 30 32 34 32 32 28 32 36Feedwater Hardness (ppm) 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1

42,000 lb/hr X 24 hr/day = 1,008,000 lb/day

1,008,000 lb/day ~ 960,000 lb/day

√

1 lb steam ~ 1,000 BTU

960,000 lb/day x 1,000 BTU/lb = 960,000,000 BTU day

1 gallon #2 fuel oil ~ 138,000 BTU

9,200 gal/day x 138,000 BTU/gal = 1,269,600,000 BTU/day

960 MMBTU ≠ 1,269.6 MMBTU

Efficiency = heat out / heat in

960 MMBTU / 1,269.6 MMBTU ~ .76 or 76%

√


System Pressures

System Temperatures Fuel Meter Readings Fuel Inventory Water Test Results Chemical additions

System Pressures (1/3):

Relatively constant boiler pressure = smooth system operations.

Stress resulting from pressure is held within acceptable limits.

Constant pressure = constant temperature (unless boiler is equipped with superheaters).

Constant temperature minimizes thermal stresses.

Wide variations in pressure indicate system problems.

System Pressures (2/3): Pressure gauges must be correct type for

the application. Have the proper range, be properly installed and calibrated.

Pressure gauges come in many types depending on the application:

System Pressure 3/3):

Looking at pressure trends:

Boiler Pressure (excessive droop or improper tuning).

Feedwater pressure (worn pump). Deaerator pressure (improper pressure control

tuning, malfunctioning steam pressure regulator, improperly sized unit, too much make-up water).

Fuel oil pump (malfunctioning regulator, worn pump, clogged strainer).

Burner oil pressure (plugged burner tip, malfunctioning regulator).

Furnace pressure (soot slag build-up, improper damper operation).


System Pressures System

Temperatures Fuel Meter Readings Fuel Inventory Water Test Results Chemical additions

System Temperature may include:

Feedwater tank or Deaereator temperatures.

Stack gas outlet temperature.

Fuel oil temperature (if burning heaver grades of fuel oil).

What should the water temperature be leaving the

deaerator:

Within 3 to 5°F of the steam temperature supplied to the deaerator.

How to we determine the pressure temperature

relationship?

We can refer to the steam tables.

How is the pressure in the deaerator controlled?

A pressure control valve or regulator is used to maintain a constant pressure in the deaerator.

remember:

constant pressure = constant temperature

Deaerators:

50 70 90 110 130 150 170 190 2100

2

4

6

8

10

12

Oxygen (ppm) vs. Temper-ature (F)

Oxygen (ppm) vs. Temperature (F)

Feedwater inlet

Steam inlet

Storage Tank

Stack Temperature:

The single biggest loss in boiler operation is heat up the stack. It can be affected by

several factors: Burner tuning. Excess air. Scale deposits. Soot deposits. Damaged refractory. Broken fire side baffles.

To Stack

Combustion Chamber

Baffles direct the flow of flue gases to allow heat to be transferred from the gases of combustion to the water in the boiler:

Baffle

Stack Temperature:



What is scale?

Scale is the collection of mineral deposits formed on the heating surfaces of a boiler.

The effect of scale:

Thickness Efficiency Loss

1/64” 4% 1/32” 7%

1/8” 18% 1/4” 38%

How does scale boiler heating surface failure?

BOILER TUBE

Stack Temperature:



What is soot?

Soot is carbon deposits caused by incomplete combustion

The effect of soot:

Thickness ~Efficiency Loss

1/32” 2.5%1/16” 5%

1/8” 9.5%


System Pressures System Temperatures Fuel Meter

Readings Fuel Inventory Water Test Results Chemical additions


System Pressures System Temperatures Fuel Meter Readings Fuel Inventory Water Test Results Chemical additions

Fuel inventory:

Fuel inventory should be recorded on a regular basis (daily is recommended).

Fuel oil tank sounding charts should be readily available or calculations must be performed.

Fuel oil tanks should be sounded before and after deliveries and checked against delivery statement for accuracy.

Fuel meter readings:

Fuel oil is ideally metered to each separate burner.

Gas is typically metered at the plant inlet.

Points to remember:1 gallon of #2 fuel oil contains ~ 138,000

BTU.1 cubic foot of natural gas ~1,000 BTU.


System Pressures System Temperatures Fuel Meter Readings Fuel Inventory Water Test

Results Chemical additions

Boiler Water Test:Typical Data -

Boiler water conductivity. Feedwater conductivity. Condensate conductivity. Boiler M-Alkalinity. Boiler sulfite. Boiler phosphate/polymer. Boiler silica. Feedwater hardness. Condensate hardness. Condensate pH.

A sudden drop in boiler sulfite residual could indicate:

A malfunctioning feed pump. A plugged injection point. A malfunctioning deaerator. Gross air in-leakage in the feedwater

system. Excessive make-up water.

Boiler Water Test:Typical Data -

Boiler water conductivity. Feedwater conductivity. Condensate conductivity. Boiler M-Alkalinity. Boiler sulfite. Boiler phosphate/polymer. Boiler silica. Feedwater hardness. Condensate hardness. Condensate pH.

Boiler Room Log Sheet #1 Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8Boiler Load (lbs/hr) 42,000 39,000 41,000 45,000 47,000 43,000 37,000 35,000Boiler (PSI) 100 99 100 100 99 100 101 100FW (PSI) 150 151 149 151 150 150 148 150D/A (PSI) 7 7 7 8 7 7 8 8Fuel Oil Pump (PSI) 150 150 151 150 149 150 150 151Boiler Burner Oil (PSI) 42 39 41 45 47 43 37 35Furnance Pressure (inH2O) 3.2 2.9 3.1 3.5 3.7 3.3 3.7 2.5Boiler Steam Total (Lbs) 960,000 831,000 942,000 998,000 1,032,000 1,008,000 1,001,000 798,000Boiler Oil Used (Gal) 9,200 7,890 9,029 9,565 9,891 9,661 9,594 7,591Lbs steam/Gal oil used 104 105 104 104 104 104 104 105Make-Up Water Total (Gal) 23,132 20,024 22,650 21,643 23,624 24,289 26,533 19,229Outside (°F) 30 31 29 28 26 29 33 34Boiler Stack (°F) 458 450 452 460 462 455 450 448Return Condensate (°F) 160 162 168 170 173 171 165 164D/A Tank (°F) 230 231 230 232 230 230 230 230Boiler Cond (micromho) 2800 2700 2800 2900 3000 2700 2800 2900Boiler M-Alk (ppm) 320 300 340 320 300 290 300 290Boiler Sulfite (ppm) 30 32 34 36 30 28 30 32Boiler Phosphate (ppm) 40 42 41 38 39 40 39 40Condensate Cond (micromho) 20 22 26 45 52 75 80 92Condensate pH 8.6 8.7 8.5 8.8 8.7 8.8 8.7 8.6Condensate Hardness (ppm) 0.1 0.1 0.1 0.4 0.6 0.8 0.8 1Make-Up Cond (micromho) 100 120 110 110 110 100 120 110Make-up Hardness (ppm) 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1Feedwater Cond (micromho) 30 32 34 32 32 28 32 36Feedwater Hardness (ppm) 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1

Increases in condensate return impurities indicate:

Possible contamination due to failed heat exchangers in the condensate system.

Improper plumbing of condensate vent lines.

Possible corrosion in the condensate system.


System Pressures System Temperatures Fuel Meter Readings Fuel Inventory Water Test Results Chemical

additions & boiler blowdown

Overall swings of boiler test results are most often the result

of: Inconsistent boiler blowdown.

Continuous blowdown

Surface blowdown

Bottom blowdown

How to measure chemical additions:

Always measure chemical feed amounts to insure consistent results.

How can we learn what the log sheet is telling us?

Operator Training!

Presented By The American Society of Power Engineers, Inc.™

A Non-Profit Cooperation

For More Information or a copy of his presentation contact:

www.asope.orgE-Mail [email protected]

866-926-1821

QUESTIONS?

http://www.asope.org/

mailto:[email protected]

maintenance shows of america april 2010 tampa florida presented by: byron nichols representing: the...

Documents

lbday slide

baffle slide

constant temperature

boiler tube slide

incomplete combustion

fuel oil temperature

constant pressure

constant boiler pressure