Regulations regarding Coal Ash Utilisation in Europe Hans-Joachim - PowerPoint PPT Presentation

Regulations regarding Coal Ash Utilisation in Europe Hans-Joachim Feuerborn European Coal Combustion Products Association NCAB_workshop_Nov. 23/24, 2005 1

Content 1. Introduction 2. Regulations for use of coal ash in - cement production - concrete - road construction 3. Environmental regulations 4. Concluding remarks NCAB_workshop_Nov. 23/24, 2005 2

Introduction Production of CCPs in Europe (EU-15) in 2003 Fly Ash 67.8 % 9.3 % 17.2 % Bottom Ash Boiler Slag, 3.2 % FGD Gypsum SDA Product, 0.8% FBC Ash 1.7 % total amount 65 million tonnes NCAB_workshop_Nov. 23/24, 2005 3

Introduction Utilisation of CCPs in Europe (EU-15) in 2003 Utilization in construction Industry Restoration of Open and Underground Mining Cast Mines, Quarries and Pits 52.4% 35.9% Disposal, 3.7% Temporary stockpile, 8.0% total amount 65 million tonnes NCAB_workshop_Nov. 23/24, 2005 4

Introduction Demands of the construction market � availability of huge amounts of material � constant quality (continuous process) � sufficient product properties (grain size distribution, surface,reactivity, ...) � long term availability � meeting of technical requirements � environmental compatibility NCAB_workshop_Nov. 23/24, 2005 5

Introduction Utilisation of fly ash in the construction industry and in underground mining in Europe (EU 15) in 2003 Concrete Concrete Blocks Addition 27.8% 5.8% Blended Road Cement 11.3% Construction, 23.4% Filling Application 25.9% Cement Infill, 3.3% Raw Material Others, 2.5% (total utilisation 21.1 million tonnes) NCAB_workshop_Nov. 23/24, 2005 6

Introduction Utilisation of Bottom Ash in the Construction Industry and Underground Mining in Europe (EU 15) in 2003 Road Construction, Filling Application 33.1% 4.6% 48.2% Others 10.4% Cement 3.7% Concrete Blocks Concrete (total utilisation 2.7 million tonnes) NCAB_workshop_Nov. 23/24, 2005 7

Introduction Utilisation of Fly Ash in the cement and concrete industry in Europe (EU 15) from 1993 to 2003 clinker raw material blended cement concrete 16 utilization in million tonnes 14 12 10 8 6 4 2 0 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 NCAB_workshop_Nov. 23/24, 2005 8

Regulations for use of coal ash for cement Chemical parameters of fly ashes from coal and lignite Parameter Fly ash from Coal Fly Ash from Lignite SiO 2 36 – 60 18 – 80 Al 2 O 3 23 – 35 1 – 19 FeO 3 3 – 17 1 – 22 CaO 0,3 – 8,5 2 – 52 CaO frei 0,1 – 25 MgO 0,5 – 5,4 0,5 – 11 K 2 O 0,5 – 6 0,1 – 2 Na 2 O 0,1 – 3,5 0,01 – 2 SO 3 0,1 – 2,1 1 – 15 NCAB_workshop_Nov. 23/24, 2005 9

Regulations for use of coal ash for cement Requirements for Siliceous and Calcareous Fly Ash by DIN EN 197-1 Parameter siliceous fly ash calcareous fly ash V W 1 W 2 ≤ 5 % by mass Loss on ignition Reactive calcium oxide 1) ≤ 10 % by mass ≥ 15 % by mass 10 – 15 % by mass ≤ 1 % by mass 2) Free calcium oxide ≥ 25 % by mass Reactive silicon dioxide 3) - Compressive strength at 28d 4) ≥ 10 N/mm² - - Expansion 5) ≤ 10 mm - - 1) CaO reactiv = total CaO reduced by fraction calculated as CaCO 3 and CaSO 4 2) CaO free -= amount up to 2,5 % by mass accepted when soundness is given (see 5) ) 3) SiO 2reactiv = fraction of SiO 2 which is soluble after treatment with HCl and boiling KOH-solution 4) mortars with ground fly ash as binder, amount < 40µm between 10 and 30 % by mass 5) mixture of 30 % by mass ground fly ash, 70 % by mass cement NCAB_workshop_Nov. 23/24, 2005 10

Regulations for use of coal ash in concrete • Utilisation of fly ash as an addition to concrete has a long history in several countries. • In 1994, the first European Standard EN 450 "Fly Ash for Concrete" was published. • About 6 million tonnes of fly ash are used as concrete addition every year in Europe. • In May 2005, the harmonized standard EN 450 part 1 and part 2 was published. This standard has to be introduced to national law in 2006. NCAB_workshop_Nov. 23/24, 2005 11

Regulations for use of coal ash in concrete Chemical Requirements for Fly Ash for Concrete by EN 450 Parameter Requirements Test Frequency Loss On Ignition max. 5.0 w.-% d SO 3 max. 3.0 w.-% m Cl max. 0.01 w.-% m max. 2.5 w.-% 1) CaO free w 1) fly ash with CaO free higher than 1 w.-% but less d : daily w: once per week than 2.5 w.-% must comply with the requirements m: once per month for soundness NCAB_workshop_Nov. 23/24, 2005 12

Regulations for use of coal ash in concrete Physical Requirements for Fly Ash for Concrete by EN 450 Parameter Requirements Test Frequency Soundness 1) max. 10 mm w Fineness 2) max. 40 w.-% d Fineness variation d 3) ± 10 w.-% ⌧ Activity index after 28 days min 75 % 2 m after 90 days min 85 % 2 m Density variation m 3) ± 150 kg/m 3 ⌧ 1) required only if CaO frei > 1,0 w.-% d : daily 2) mass proportion in % of the ash retained when wet sieved w: once per week m: once per month on a 0,045 mm mesh sieve 3) average value as declared by the producer 2 m: twice per month NCAB_workshop_Nov. 23/24, 2005 13

Regulations for use of coal ash in concrete EN 450-1 Fly ash for concrete - Part 1: Definition, specifications and conformity criteria EN 450-2 Fly ash for concrete - Part 2: Conformity evaluation NCAB_workshop_Nov. 23/24, 2005 14

Regulations for use of coal ash in concrete EN 450-1: Fly ash for concrete Definition of fly ash fine powder of mainly spherical particles, derived from burning of pulverized coal, with or without co-combustion materials, which has pozzolanic properties and consists essentially of SiO 2 and Al 2 O 3 ,... � Reactive SiO 2 min 25 % by mass � Reactive CaO max 10 % by mass NCAB_workshop_Nov. 23/24, 2005 15

Regulations for use of coal ash in concrete EN 450-1: Fly ash for concrete New items of EN 450 � Introduction of three categories of loss on ignition � Introduction of two categories of fineness � Acceptance of fly ash obtained from co-combustion � Consideration of processing plants as production plants NCAB_workshop_Nov. 23/24, 2005 16

Regulations for use of coal ash in concrete EN 450-1: Fly ash for concrete LOI Categories of EN 450-1 Category LOI in % by mass min max A - 5.0 B 2.0 7.0 C 4.0 9.0 NCAB_workshop_Nov. 23/24, 2005 17

Regulations for use of coal ash in concrete EN 450-1: Fly ash for concrete Fineness Categories of EN 450-1 Category Amount retained on a Fineness variation from 0.045 mm mesh sieve declared value in% by mass in percentage points N 40 ± 10 S 12 no requirement NCAB_workshop_Nov. 23/24, 2005 18

Regulations for use of coal ash in concrete EN 450-1: Fly ash for concrete Types of Co-combustion Materials 1 Vegetable material like wood chips, straw, olive shells and other vegetable fibres 2 Green wood and cultivated biomass 3 Animal meal 4 Municipal sewage sludge 5 Paper sludge 6 Petroleum coke 7 Virtually ash free liquid and gaseous fuels NCAB_workshop_Nov. 23/24, 2005 19

Regulations for use of coal ash in concrete Limitation of Co-combustion Materials � Minimum percentage of coal (K c ) shall not be less than 80 % by mass of the fuel � Maximum proportion of ash from co-combustion materials (M) shall not be greater than 10 % by mass of the fly ash ⋅ + ⋅ + + ⋅ K A K A .... K A = ⋅ ≤ 1 1 2 2 n n M 100 10 % ⋅ + ⋅ + ⋅ + + ⋅ K A ( K A K A .... K A ) c c 1 1 2 2 n n K i a nd K c are the proportions of co-combustion materials and coal being fired A i and A c are the ash contents of the co-combustion materials and the coal NCAB_workshop_Nov. 23/24, 2005 20

Regulations for use of coal ash in concrete EN 450-1: Fly ash for concrete The new standard covers also fly ash produced by: • classification • blending • selection • grinding • sieving • carbon reduction • drying NCAB_workshop_Nov. 23/24, 2005 21

Regulations for use of coal ash in concrete Processing Plants in Europe United Kingdom • classification (BS 3892) • carbon reduction (ST I - process) STI separation unit installed at: - Longannet Power Station (Scotland) - Didcot Power Station (England) NCAB_workshop_Nov. 23/24, 2005 22

Regulations for use of coal ash in concrete Processing Plants in Europe The Netherlands • silo, mixing and sieving installation (SMZ centre, Rotterdam) SMZ Center in Maasflakte near Rotterdam construction in 1995 capacity 250.000 tpa (source: Vliegasunie) NCAB_workshop_Nov. 23/24, 2005 23

Regulations for use of coal ash in concrete Processing Plants in Europe France • re-drying facilities (Carling, Hornaing) Hornaing; capacity 50 tph Carling; capacity 80 tph (source: Surschiste) NCAB_workshop_Nov. 23/24, 2005 24

Regulations for use of coal ash in concrete Processing Plants in Europe Germany • re-drying facility (Lünen) capacity 60.000 tpa (source: SEG) NCAB_workshop_Nov. 23/24, 2005 25