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Key departmental publications, e.g. annual reports, budget papers and program guidelines are available in our online archive.

Much of the material listed on these archived web pages has been superseded, or served a particular purpose at a particular time. It may contain references to activities or policies that have no current application. Many archived documents may link to web pages that have moved or no longer exist, or may refer to other documents that are no longer available.

Adelaide Malting Pty Ltd - Cleaner Production
Cogeneration Helps Reduce Malting Costs

Adelaide Malting have improved their energy efficiency through the replacement of electricity-powered fans with gas engine-powered fans. Heat recovered from the gas engine is used for malt drying, avoiding the need for electricity-powered malt drying technology. As well as reducing energy consumption, the initiative has boosted plant capacity by 20 percent.

Background

Adelaide Malting, part of the Coopers Brewery Group of Companies, produces barley malt for the local, interstate and overseas beer-brewing industry.

The company operates from modern facilities at Cavan, about 10 kms north of Adelaide, South Australia. It has a full-time staff of 20, an annual turnover of $20-25 million, and is the third largest maltster in Australia. Current annual production of malted barley is 64,000 metric tonnes (mt).

Adelaide Malting was the first maltster in Australia to be accredited with the ISO 9002 quality systems accreditation.

The Process

In the malting process, barley undergoes steeping (soaking), germination and kilning (drying).

Adelaide Malting has two production units on the one site, which both utilise common barley and malt storage, barley and malt cleaning, steep water and refrigeration facilities.

Plant No.1 operates at its designed capacity of 24,000mt per annum. Plant 2 has four germination boxes giving a capacity of 40,000mt per annum.

Computerised facilities ensure that humidity and temperature produce ideal germination rates. As well, daily batch analysis of malt in process ensures that the resultant product will contribute most efficiently to the subsequent brewing process.

In kilning, fans blow large volumes of air, preheated to 70 to 80 degrees Celsius, to remove water from wet grain.

Prior to the installation of the gas engines, air was heated by a natural gas direct fired Low NOx burner system and blown through the grain beds using three, 70 kW electric fans.

Heat recovery plant

Heat recovery plant

Cleaner Production Initiative

A detailed study by the local gas supply company (The Gas Company) into using on-site power generation, concluded that the most cost effective approach was to direct drive the major fan on the site using a gas engine fitted with heat recovery to partly heat the malt drying air.

Initially (1994), the gas powered engine fitted with heat recovery drove a single large fan,  replacing three electrically driven fans, reducing the maximum electrical demand of the site by 210 kW and increasing processing capacity by 20 percent. Heat recovered from the unit reduced the firing rate of the gas burner by about 15 percent. In 1995, as a result of proven energy savings in Plant 1, two gas engines were selected to drive the kiln fans in Plant 2, together with heat recovery to pre-heat the kiln air.  

Cogeneration system flow diagram

Cogeneration system

Advantages of the Process

The system recovers almost all the energy input to the engine. The only heat lost is that radiated from the engine and gearbox surfaces and the loss in the 120 degree Celsius exhaust gases. The overall efficiency of the plant, including mechanical shaft work, is approximately 90 percent.

The process operates continuously, except for a few hours each month when the engine oil is changed and preventative maintenance carried out.

Cost

$175,000

Payback Period

2+ years

Annual Savings:
Gross
Net


$100,000
$70-75,000

Cleaner Production Incentive

Given the electrical constraints of the site, on-site power generation with heat recovery was a natural choice when considering ways of expanding plant capacity.

Adelaide Malting is continually striving to improve the efficiency of its operations and the quality of its product. This initiative was one element in this on-going improvement strategy.

Barriers

No barriers were encountered. The plant was designed and built by The Gas Company. Adelaide Malting specified and installed the fan and associated duct work connections.

Further Developments

In 2000, Adelaide Malting also installed a 230kW genset with heat recovery to generate electricity at approximately 55 percent of the cost of retail power. This latest improvement has resulted in four identical gas engines on site with all maintenance carried out internally. The genset supplies the total power needs for Plant 2, with heat recovery into the kiln in parallel with Engines 2 and 3.

Heat Recovery Layout at 2001 Diagram

Heat Recovery Layout at 2001

Contact

Bill Gill
Managing Director
Adelaide Malting Pty Ltd
30 Cardiff Court
Cavan  SA  5094
Ph: 08 8349 6155
Fax: 08 8349 4321
Email: bgill@admalt.com

Implementation: 1994
Further initiatives: 1995, 2000
Case study initially prepared: April 1998 by the Environment Management Industry Association of Australia
Last modified: May 2001

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