National Cement Company. P.S.C Dubai LOESCHE SYMPOSIUM: Cost saving as result of conversion from HFO to pulverized coal Presented by: Eng. Radwan Mouakat Düsseldorf, 25.09.2014
National Cement Company P.S.C Dubai
Dubai City in year 1976
Dubai City Today
Today in the heart of Dubai City National Cement Co. P.S.C Dubai Works
National Cement Co. Works in brief Commissioned wet process in 1978 Converted to dry process in 1987
National Cement Co. Works in brief Current capacity 4000 tpd Original heat source was HFO Conversion to coal firing since 2012
Fuel price from 2004 to 2012 (USD/TON)
Consumption of fuel per ton of clinker
Challenges Rising price of heavy oil and gas Difficult market conditions Strong impact on production costs Cost reduction challenge Decision cost saving conversion from HFO to pulverized coal
Selection A Strategic Decision Selection of the Coal grinding Company? For cost saving as result of conversion from HFO to pulverized coal
Concepts and Considerations Coal Grinding Plant Concepts and Considerations
Processing Design latest regulations regarding constructions Lay-out and operation of coal handling facilities Safety regulations Modern fuel efficient kiln types Drying of coal Grindability of coal meal fineness Mill for grinding of coal
Conditions Arrangement of coal grinding plant: There are various factors have to be taken into considerations when arranging a coal grinding plant: Quality of coal Supply of hot air for drying Type and numbers of Kiln Investment cost Maintenance cost Reliability
Conditions Based on evaluation of these matters, decision can be made regarding the following: Direct, semi-direct or indirect firing Inert or non-inert operation Ball mill or Vertical Roller Mill Bag Filter or EP for possible dedusting Instrumentation & automation of the coal grinding plant Filters and coal mills silos
Conditions Coal stacking and storing Other Safety precautions, the following tips should be considered: Feeding arrangement, to ensure steady feed of raw coal to the mill. Horizontal surfaces, where coal may settle. Ducts should have proper inclinations (min. 60 upwards and 45 downwards.) Gas velocity in ducts (min. 20m/sec.)
Conditions Mill separator, duct between separator and filter, filter and coal meal silos should be fitted with pressure relief valve, which must open to the outside air, not inside the buildings. The installations mechanical and electrical equipment to be well maintained for future maintenance. Buildings and equipment should be kept clean Common sense: To consider the operation, designed plant which is in accordance with current industrial standards, to reduce risks.
Benefits Lower energy consumption Higher drying capacity Output capacity can easily be varied within a wide range corresponding to the fuel consumption of the Kilns Fast feed output response Accept larger feed sizes up to 80mm Lower noise level Requires less building volume
Challenges Larger quantity of air to be dedusted Less suitable for abrasive coal. Wear parts are expensive and replacement causes downtime. Sensitive to variations in feed rate and feed quantity
Result of selection and evaluation A Strategic Decision Selection of the Coal grinding Company LOESCHE GmbH For cost saving as result of conversion from HFO to pulverized coal
Beginning in 2012
Why LOESCHE Vertical Roller Mill One Compact System, comprising grinding, drying and classification Stable running conditions, hence easy to operate Easy to maintain and reduced specific wear rates Highly energy efficient Very flexible grinding system
LOESCHE Coal Mill in the City of Dubai Mill Type: LM 28.2 D Feed Material: Hard Coal Throughput (design): 40 tph Product Fineness: 12%R90μm Drive Capacity: 600 kw Commissioned:2012
National Cement Co. Coal Mill Building
Share Vertical Mills for Coal Grinding Numbers represent the year 2007/08
LOESCHE Mill Flow-sheet
Pulverized Coal Dosing Dosing Unit DRW 4.12/2 DRW 4.12/2 Type Rotor weigh feeder Rotor weigh feeder Material Coal Dust Coal Dust Capacity 16,2 t/h 17,8 t/h Application Calciner Main Burner Commissioning 02.05.2012 02.05.2012 Bulk Density 0,35 0,6 t/m 3 0,35 0,6 t/m 3 Distance of Feed Line 70m 123m
Raw coal specifications S.NO SPECIFICATIONS UNIT SPECIFICATION YEAR 2013 YEAR 2014 01 TOTAL MOISTURE % MAX - 8.50 7.58 8.93 02 INHERENT MOISTURE % MAX - 3.50 1.60 1.86 03 GROSS CALORIFIC VALUE Kcal/k g MIN - 6400 6438.11 6549.72 04 SULPHUR % MAX - 1.00 0.60 0.61 05 ASH CONTENT % MAX - 16.00 15.91 15.01 06 VOLATILE MATTER % MAX - 26.00 28.02 29.00
Coal price for the year 2012
Market prices for coal 2013 & 2014
Coal consumption COAL CONSUMPTION PER TON OF CLINKER FROM JUNE - DEC. 2012 0.13 0.125 0.12 M. TON 0.115 JAN. FEB. MARC APRIL MAY JUNE JULY AUG. SEPT. OCT. NOV. DEC. M. TON 0.1241 0.1249 0.1248 0.1211 0.1244 0.1243 0.1277 CONSUMPTION OF COAL PER TON OF CLINKER FOR THE YEAR 2013 0.135 0.13 0.125 M.TON 0.12 0.115 JAN. FEB. MARC APRIL MAY JUNE JULY AUG. SEPT. OCT. NOV. DEC. M.TON 0.1263 0.1296 0.1281 0.1290 0.1312 0.1326 0.1265 0.1266 0.1225 0.1237 0.1225 0.1229 CONSUMPTION OF COAL PER TON OF CLINKER FROM JAN. - JULY 2014 0.135 0.13 0.125 M.TON 0.12 JAN. FEB. MARC APRIL MAY JUNE JULY AUG. SEPT. OCT. NOV. DEC. M.TON 0.1255 0.1244 0.1324 0.1283 0.1250 0.1252 0.1252
Alternative fuels
Alternative fuels Such fuels as wood chips, sludge, used car tyres or even house hold garbage.. etc. The application of these fuels are becoming more and more interesting. There is no doubt that in the future the cement kiln will be used more and more as incineration plant for disposal of hazardous waste. In this regard, we are nowadays using carbon dust which is available in Aluminium industry with reasonable Price, also full unit of used car tyres.
Carbon Dust Specifications S.NO SPECIFICATION UNIT YEAR-2013 YEAR-2014 01 GROSS CALORIFIC VALUE CARBON DUST GRADE-I CARBON DUST GRADE- II CARBON DUST GRADE-I CARBON DUST GRADE- II Kcal / Kg 7562.26 3586.11 7534.07 4095.51 02 SULPHUR % 1.69 1.07 1.48 1.30 03 ASH CONTENT % 3.01 45.68 2.85 38.23
Alternative fuels
Alternative fuels PERCENTAGE OF COAL AND ALTERNATE FUEL FROM JUNE 2012 TO JULY 2014 100.00 95.00 90.00 85.00 80.00 75.00 70.00 65.00 60.00 55.00 50.00 45.00 40.00 35.00 30.00 25.00 20.00 15.00 10.00 5.00-94.90 91.45 92.40 % 5.10 8.55 7.60 2012 2013 2014 COAL ALTERNATE FUEL
Energy cost ENERGY COST IN USD/TON OF CLINKER 60.00 50.00 40.00 30.00 Series1 20.00 10.00 - FUEL OIL COAL COAL + CARBON DUST COAL + TYRES COAL + CARBON DUST + TYRE Series1 51.70 13.67 13.30 13.16 12.79
Energy cost ENERGY COST IN USD/TON OF CLINKER 15.00 14.00 13.00 12.00 Series1 11.00 10.00 COAL COAL + CARBON DUST COAL + TYRES COAL + CARBON DUST + TYRE Series1 13.67 13.30 13.16 12.79
Thank you very much for your kind attention!