nt face=arial size=-1 color=black>Yahoo! is not affiliated with the authors of this page or responsible for its content.
Integrated Pollution Prevention and Control Reference Document on Best Available Techniques in Edificio EXPO, c/ Inca Garcilaso s/n, E-41092 Sevilla - Spain
Telephone: direct line (+34-95) 4488-284, switchboard 4488-318. Fax: 4488-426.
Internet:
http://eippcb.jrc.es
; Email:
eippcb@jrc.es


EUROPEAN COMMISSION
DIRECTORATE-GENERAL JRC
JOINT RESEARCH CENTRE
Institute for Prospective Technological Studies
Technologies for Sustainable Development
European IPPC Bureau

















Integrated Pollution Prevention and Control

Reference Document on Best Available Techniques in
the Smitheries and Foundries Industry


July 2004




Executive Summary - Smitheries
i
EXECUTIVE SUMMARY

The Smitheries and Foundries BREF (Best Available Techniques reference document) reflects
an information exchange carried out under Article 16(2) of Council Directive 96/61/EC. This
executive summary is intended to be read in conjunction with the BREFs Preface, which
explains the structure of the document, its objectives, usage and legal terms. The executive
summary describes the main findings, the principal BAT conclusions and the associated
emission/consumption levels. It can be read and understood as a stand-alone document but, as a
summary, it does not present all the complexities of the full BREF text. It is therefore not
intended as a substitute for the full BREF text in BAT decision making.


Scope of this BREF

This document reflects the exchange of information on the activities covered by Annex I,
categories 2.3 (b), 2.4 and 2.5 (b) of the IPPC Directive, i.e.

2.3. Installations for the processing of ferrous metals:
(b)
smitheries with hammers the energy of which exceeds 50 kilojoule per hammer, where
the calorific power used exceeds 20 MW
2.4. Ferrous metal foundries with a production capacity exceeding 20 tonnes per day
2.5. Installations
(b)
for the smelting, including the alloyage, of non-ferrous metals, including recovered
products, (refining, foundry casting, etc.) with a melting capacity exceeding 4 tonnes
per day for lead and cadmium or 20 tonnes per day for all other metals.

After comparing the above descriptions to the actual capacitites of existing installations in
Europe, the TWG outlined a working scope, which covered the following:

- the casting of ferrous materials, e.g. lamellar cast iron, malleable and nodular iron, steel
- the casting of non-ferrous materials, e.g. aluminium, magnesium, copper, zinc, lead and
their alloys.

Smitheries were excluded from this documents scope since no European smitheries were
reported which met the conditions stated in Annex I 2.3.(b). This document therefore only
discusses foundry processes. Cadmium, titanium and precious metals foundries, as well as bell
casting and art casting foundries were also excluded on capacity grounds. Continuous casting
(into sheets and slabs) has already been covered in the BREF documents related to iron and
steel production and non-ferrous metal industries, and therefore, it is not dealt with in this
document. In covering non-ferrous metals in this document, the process is considered to start
with the melting of ingots and internal scrap or with liquid metal.

From a process point of view, the following foundry process steps are covered in this document:

- pattern making
- raw materials storage and handling
- melting and metal treatment
- mould and core production, and moulding techniques
- casting or pouring and cooling
- shake-out
- finishing
- heat treatment.
Executive Summary - Smitheries

ii
The foundry industry

Foundries melt ferrous and non-ferrous metals and alloys and reshape them into products at or
near their finished shape through the pouring and solidification of the molten metal or alloy into
a mould. The foundry industry is a differentiated and diverse industry. It consists of a wide
range of installations, from small to very large; each with a combination of technologies and
unit operations selected to suit the input, size of series and types of product produced by the
specific installation. The organisation within the sector is based on the type of metal input, with
the main distinction being made between ferrous and non-ferrous foundries. Since castings in
general are semi-finished products, foundries are located close to their customers.

The European foundry industry is the third largest in the world for ferrous castings and second
largest for non-ferrous. The annual production of castings in the enlarged European Union
amounts to 11.7 million tonnes of ferrous and 2.8 million tonnes of non-ferrous castings.
Germany, France and Italy are the top three production countries in Europe, with a total annual
production of over two million tonnes of castings each. In recent years, Spain has taken over the
fourth position from Great Britain, with both having a production of over one million tonnes of
castings. Together, the top five countries produce more than 80 % of the total European
production. Although the production volume has remained relatively stable over the past few
years, there has been a decline in the total number of foundries (now totalling around 3000
units), which is also reflected in the employment numbers (now totalling around 260000
people). This can be explained by progressive upscaling and automation in the foundry units.
However, the foundry industry is predominantly still an SME industry, with 80 % of companies
employing less than 250 people.

The main markets served by the foundry industry are the automotive (50 % of market share),
general engineering (30 %) and construction (10 %) sectors. A growing shift of the automotive
industry towards lighter vehicles has been reflected in a growth in the market for aluminium and
magnesium castings. While iron castings mostly (i.e. >60 %) go to the automotive sector, steel
castings find their market in the construction, machinery and valve making industries.


The foundry process

A general flow chart of the foundry process is depicted in the figure below. The process can be
divided into the following major activities:
- melting and metal treatment: the melting shop
- preparation of moulds and cores: the moulding shop
- casting of the molten metal into the mould, cooling for solidification and removing the
casting from the mould: the casting shop
- finishing of the raw casting: the finishing shop.

Various process options can be taken, depending on the type of metal, size of series and type of
product. Generally, the main division within the sector is based on the type of metal (ferrous or
non-ferrous) and the type of moulding used (lost moulds or permanent moulds). While any
combination is possible, typically ferrous foundries largely use lost moulds (i.e. sand moulding)
and non-ferrous foundries mainly use permanent moulds (i.e. die-casting). Within each of these
basic process options a variety of techniques exist according to the type of furnace used, the
moulding and core-making system (green sand or various chemical binders) applied, and the
casting system and finishing techniques applied. Each of those have their own technical,
economic and environmental properties, advantages and disadvantages.

Chapters 2, 3 and 4 of this document follow a process-flow approach to describe the various
operations, from pattern making to finishing and heat treatment. Applied techniques are
described, emission and consumption levels given and techniques to minimise the
environmental impact are discussed. The structure of Chapter 5 is based on a distinction
between the type of metal and the type of moulding. Executive Summary - Smitheries
iii
Melting
- ferrous:
cupola
induction
electric arc
rotary
- non-ferrous:
induction
shaft
crucible
reverberatory
Metal treatment
Permanent
mould
maintenance
Lost mould making
- sand mould
- sand core
- inserts
- pattern
wood, plastic,
metal
- lost model
resin, wax
Manual moulding
Moulding automate
Casting
-
gravitational pouring
- high-pressure
- tilt pouring
- centrifugal
- low-pressure
- continuous
Cooling
Shake-out / Take-out
Sand preparation
Sand regeneration
Finishing
-removal of casting system
-shot blasting
-deburring
-thermal treatment
Raw materials, chemicals, patterns, dies
Finished casting
Sand
Legend:

The foundry process


Key environmental issues

The foundry industry is a major player in the recycling of metals. Steel, cast iron and aluminium
scrap is remelted into new products. Most possible negative environmental effects of foundries
are related to the presence of a thermal process and the use of mineral additives. Environmental
effects therefore are mainly related to the exhaust and off-gases and to the re-use or disposal of
mineral residues.

Emissions to air are the key environmental concern. The foundry process generates (metal-
laden) mineral dusts, acidifying compounds, products of incomplete combustion and volatile
organic carbons. Dust is a major issue, since it is