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Cement

CI/SfB I I (90.4) I s I I

Fly Ash BSEN 450 1 Class N Category 100%

non-primary materials

FM96927OHS61759

EMS96928

EN 450 N is a Quality Assured processed Fly Ash (also known as Pulverised Fuel Ash, or abbreviated to PFA).

Fly Ash is supplied to the readymixed concrete and concrete product markets as a cement replacement.

Using Fly Ash as a cement replacement

reduces the overall CO2 footprint of the

concrete. When PFA is used in concrete

environmental savings can equate

to 20% reduction in overall CO2 emissions

for 30% Fly Ash content (based on mixes

designed with equal 28 day strengths).

Improved surface finish of the

completed structure. Fly Ash contributes

to producing a more cohesive concrete

which has a reduced rate of bleeding

making it easier to compact and giving

the concrete better pumping properties.

Reduces permeability, which reduces

shrinkage, creep and gives greater

resistance to chloride ingress andsulphate attack. Pozzolans such as

PFA react with lime (alkali calcium

hydroxide produced by cement hydrating)

to form stable calcium silicates and

calcium aluminate hydrates. These fill the

voids in the concrete and remove some

of the lime which reduces the permeability

of the concrete.

Improves long term strength,

performance and durability.The Fly Ash

reaction with lime also improves the

strength, durability, chloride and sulfate

resistance of the concrete.

Using Fly Ash reduces the temperature

rise in thick sections with the addition of

less cement in a concrete mix the heat

that is produced through hydration is

greatly reduced.

Minimises risk of Alkali Silica reaction -

Alkali Silica reaction is significantly reduced,

if not completely eliminated, with the use of

more than 25% of PFA. This is due to the

fact that PFA readily reacts with sodium

and potassium alkalis within the concrete.

Admixtures can be used to extend the

properties of Fly Ash in concrete, mortars

and grouts.

Applications

Aggregate Industries Fly Ash can be combined

with Type CEM I cement to produce material

conforming to BSEN 1971.

Basic oxide composition

Component Average %

by weight

SiO2 45 to 51

AI2O3 27 to 32

Fe2O3 7 to 11

CaO 1 to 5

MgO 1 to 4

K2O 1 to 5

Na2O 0.8 to 1.7

TiO2 0.8 to 1.1

SO3* 0.3 to 1.3

Cl 0.05 to 0.15

* Water soluble. The figures for SiO2 do not refer tofree silica but to silicon present as silicates of

varying compositions.

Byproduct from coal fired power generation.

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Fly Ash BSEN 450 1 Class N Category

Specification

BSEN450 1 CLASS N CATEGORY B LOI

FLY ASH is classed as a TYPE II ADDITION,

defined in BSEN 2061 CONCRETE as a

finely divided inorganic pozzolanic or latent

hydraulic material used in cements in order

to improve certain properties or to achieve

special properties.

Complies with the requirements of BSEN

450 1 FLY ASH FOR CONCRETE,

DEFINITIONS, REQUIREMENTS AND

QUALITY CONTROL.

Can be combined with CEM 1 Cement to

BSEN 1971 Type CEM I at the concrete

mixer or the cement factory to produce

CEM 1 Fly Ash cements conforming to

BSEN 1971:2000.

Aggregate Industries Fly Ash is permitted

to be used in concrete according to

BS8500:2006 COMPLIMENTARY BRITISH

STANDARD TO BSEN2061.Fly Ash can

also be used to produce a wide range of

cementitious products and is suitable as a

filler or additive in concrete products.

Life

Life is our range of sustainable products and

services. For more information please visit

www.aggregate.com/life

Production of Fly Ash at UK power stations

When pulverised coal is burnt the Fly Ash

has to be removed from the flue gases before

they are released into the atmosphere. The Fly

Ash is therefore precipitated from the gas, first,

by mechanical separation and then by a series

of two or three electrostatic precipitators which

progressively remove fine particles, so the

last stage of precipitation collects the finest

material of all.

As a base raw material Fly Ash is variable

for several reasons, including the sources

of the coal, the efficiency of its pulverisation,

and above all the furnace in which the

pulverised coal is burnt and then the

method of precipitating the ash from the

combustion gases.

In principle the furnace acts as a particle

separator. About 20% of the ash particleseither form together or combine into a form

of clinker, which falls to the bottom of the

furnace and is known as furnace bottom

ash. The remaining 80% is known as Fly

Ash and it is this material that is normally

considered as an artificial pozzolan.

Pozzolans

Pozzolans are either naturally or artificially

produced materials that, when mixed in

finely divided form in concrete, chemically

react at normal temperatures with the

Calcium Hydroxide (LIME) that it is produced

during the hydration of the CEM 1 Cement.

All concretes made with CEM 1 Cement

alone produce an excess of lime which

weakens the concrete because it is porous

and chemically vulnerable to acids, carbon

dioxide and soluble sulphates. If a material

such as a pozzolan that combines with and

fixates the lime, is added under controlledconditions, the result is a stabilized hydrate

that is not only stronger but also less

permeable to chemical attack.

Manufacturing standard

All Aggregate Industries products are supplied

in accordance with BS ISO 9001:2008, BS

ISO 14001:2004 & BS OHSAS 18001:2007.

Logistics

Aggregate Industries supplies PFA to its

national customer base in pressurised

road tankers.

COSHH data

COSHH data on Aggregate Industries

products is available on request.

Technical support

For technical support please call our

Technical Services on: 01469 585806.

Reports of tests providing data on

chemistry and fineness are available.

Unit 2 & 3 Yarborough Court,

Front Street, Ulceby. Nr Grimsby,

North Lincolnshire DN39 6RZ

Tel: +44 (0) 1469 585806

Fax: +44 (0) 1469 588912

The information contained within this publication was accurate at time of

production. However, Aggregate Industries reserves the right to introduce

modifications or changes to detail at any time without notice. No charge is

levied for this publication or advice therein, and accordingly the company,

its employees and authorised agents can accept no liability whatsoever,

either indirectly or directly arising from the use of its products in connection

Aggregate Industries UK Limited. July 2013 with any information or advice contained in this guide.

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