Figure 1: Sand Flows in the Queensland Foundry Industry

	The Queensland Foundry Industry
New Sand Purchased 48,700 tpa		Spent Sand 46,400 tpa
	Sand Lost (< 5% baghouse dust & general loss) 2,300 tpa	Landfill 85%   Beneficial Reuse 15%

As depicted in Figure above, the average rate of internal sand reclamation for the Queensland foundry industry as a whole is currently 36%. Based on stated plans by several Queensland foundries, the industry average could potentially increase to 50% within the next two years.

Moving beyond 50% recovery will be relatively difficult. A further 5% may be gained if companies improve the efficiency of the current systems. Further gains will probably only be possible through the greater use of thermal reclamation, by improving moulding techniques to reduce the sand input, by changing to different casting processes or by identifying cost effective methods for sand reclamation at small foundries.

While significant work has already been undertake, most Queensland foundries recognise that there are many opportunities for continuous improvement in terms of by-product minimisation and for improving resource efficiency. Key areas identified by the sector include improved sand reclamation, metal yields, energy efficiency and the beneficial reuse of by-products. All of these opportunities are discussed in further detail in this report.

a) non-secured, b) relatively, c) ferrous, d) human, e) heavy, f) solid,

g) costs, h) thermal, i) stated, j) efficiency, k) dust, l) by-product

1. Wastes generated from ferrous foundries are relatively benign.

2. Most chemical additives used for sand binding can rather easily be decomposed.

3. Waste sand from ferrous foundries is usually sent to secured landfill.

4. The presence of heavy metals in the non-ferrous foundry sands is the reason for their sending to secured landfill.

5. Bag-house dust from ferrous foundries is dark and heavy so it is very harmful for health.

6. Changing energy sources means using bagasse instead of grid power, natural gas instead of propane, electricity instead of diesel.

1. The major waste streams of ferrous foundries are sand, bag-house dust and slag.
2. The ferrous foundries hope to achieve 100% reuse for their major waste streams in the nearest future.
3. The volume of material going to landfill is planned to be reduced by 25,000 tonnes per year.
4. Reuse of wastes can reduce the cost of purchasing materials as well as reducing the cost of unnecessary processing, handling and disposal costs.
5. Major foundries seek to minimise waste and maximise resource efficiency.
6. A number of foundries are in the process of installing manual sand reclamation systems or optimising the systems to increase recovery rates.
7. One of the Queensland foundries, using a shell casting process, has recently commenced thermal sand reclamation to recover 100% of its waste sand.
8. There are many opportunities for continuous improvement in terms of by-product minimisation and for improving resource efficiency.

1) ‘End-of-pipe’ strategy;

2) On-site sand reclamation;

3) Changing energy sources.

1) What are the impacts of foundry industry on the environment?

2) How can waste materials be disposed?

3) Where is spent foundry sand generated in Queensland disposed?

4) Is it possible to achieve 100% beneficial reuse for the major waste streams?

5) Can you give some examples of waste minimization?

shot-blast dust, steel, ladle lining, rolls, iron ore, bag-house dust, raw materials, non-ferrous alloys, solid metal charge, steel sheets, spent green sand, used pots, iron and steel scrap, steel bars, flux, fuel, dross, high-strength irons, large-section billets, chips, air emissions.