Energy Waste Solutions
Introduction
The Waste Minimisation Project presents a unique opportunity for Australian Industry to work Cooperatively on Waste Issues. The collaborative nature of the Project extends to a commitment by member companies, of disseminating Case Studies that will benefit Industry as a whole. The following Case Studies represent a series that showcase successful projects, undertaken by companies committed to Environmental Waste Management.Case Study 1:
Arnotts is one of the largest biscuit companies in the world, with seven manufacturing sites in Australia and the Pacific. The site at Huntingwood, NSW is a new factory with state of the art facilities and fully automated production. Even with this site being of the latest design, there have still been considerable gains to be made by looking for sources of energy efficiency.
In line with the Arnotts environmental policy to use all resources efficiently with low amounts of wastage Arnotts has been keen to implement changes to reduce the use of energy throughout the Huntingwood site. A range of projects have been undertaken in the areas of reducing gas and electricity consumption including the reconfiguration of a gas oven to reduce consumption by over 60%, the reduction in energy used to light the offices and services tunnels with no effect on the operating environment and the conversion of the warehouse from LPG to natural gas.
The success of these reduction measures is being capitalised on by continually looking for new opportunities. Currently they are exploring the options for co-generation to enable the installation of an efficient and low cost method of desalination of waste water from the production processes. They are also monitoring the chilled water tower for the air-conditioning system to determine the scope of reductions available in this system.
Lighting of Service areas
With the Huntingwood site being a high consumer of energy, the average electricity demand per month is around 600,000 kWh, it was envisaged that there would be a variety of areas in which savings could be demonstrated. The company set out to identify these opportunities by engaging energy consultants, their first stop was an audit of the lighting levels in the factory. This audit highlighted the areas that were typically forgotten or overlooked and realised that there were significant dollar savings to be made. This has been demonstrated by the project undertaken to review the lighting requirements of the service areas and halls. Normally these areas are frequented only once a week, yet they were being lit at a constant level 24 hours a day.
The intiatives implemented to reduce the energy consumption in the service areas and halls consisted of two small but significant modifications to the lighting system:
· Installation of time delay switches in the service areas. Allowing automatic switch off after a preset time interval
· Installation of daylight sensors which adjust the lights according to the available natural lightingThese simple and effective measures resulted in a reduction in the use of around 260,000 kWh per annum for a capital outlay of just over $17,000. This investment translated into a payback period of less than 1.5 years.
Case Study 2:
Background
Futuris Brakes International, manufactures friction brake shoes and disc brake pads for locomotive, freight car and transit applications. Up until six years ago, Futuris sold product solely to a domestic market. Since then sales have grown to a point that sees 60% of product exported to all corners of the globe, including Asia, North and South America, Africa and Europe. The life expectancy of a typical brake shoe or pad on a Tangarra, for example is about 3 months. This is still 5-10 times longer than a comparable cast iron product but necessitates constant stock replenishment all over the world, to keep up with what is close to a consumable item. Environmentally conscious production is therefore a high priority given the amount of dust generated by the manufacturing process.The Process
Futuris uses 50 machines throughout its Wetherill Park,NSW site. Compressed air is connected to each machine to aid in cooling during the production process or to keep equipment clean and free of dust. Typical of the machinery in use is:
· Hot Moulding Presses
· Stamping Presses
· Mixers
· Blenders
· Assembly stationsThis initiative was selected because compressed air losses could be readily measured and any improvement would have a significant impact on the environment whilst reducing production costs.
Also, proposed solutions were not capital intensive and would be easier to sustain.
Another factor was the non-threatening nature of the project, which would have minimal effect on disturbing employee relations.
The Initiative
The compressed air system was monitored on a non-production day so leaks could be easily identified.
Initially, 22 leaks, displaying a range of causes were found across all machine types.
The causes fell into the following main categories:
· Faulty diaphragms
· Loose nuts on air guns
· Redundant air hoses
An air leak calculator was downloaded from the Sustainable Energy Development Authority web-site(SEDA - www.seda.nsw.gov.au). This was used to measure exact losses, savings could then be converted into dollars and the number of tonnes of CO2 not being released into the atmosphere.
A progressive maintenance program was developed to fix the 22 leaks. The main feature of the program was its low cost due to the fact that only minor parts and minimal labour were needed to fix the problem.
The opportunity was also taken to install snap on quick connection fittings. This facilitated the isolation of machines, where previously many machines could only be maintained en masse and excessive downtime was a problem.
Achievements and Savings
Based on the SEDA calculator, annual savings of $43,000 are projected.
More importantly, nearly 500 tonnes of harmful co2 will not end up polluting our atmosphere.
This is equivalent (and much easier) to removing 110 cars from the road.
Savings or improvements of a less quantifiable nature are as follows:
· Less wear and tear on the compressor
· Less noise pollution
· A safer working environment, compressed air being a very dangerous commodity.
Lessons Learned
Many lessons were learned in the course of this project, not the least being the willingness to address the use of a commodity previously thought of as an expendable, non-measurable item.
Futuris learnt that:
· Compressed air usage should be classified as a utility and therefore a cost.
· Substantial savings can be realised without excessive capital outlay and resources.
· As a project it is easy to measure and fix
· The relative 'cost' of compressed air came as a surprise.
Finally, as energy prices increase, an initiative such as this will become an even more valuable and non-negotiable undertaking.
Case study 3:
Sara Lee Bakery Australia manufactures and markets a large range of products for the Retail, Foodservice, Sara Lee Bakery Shops and Export Markets. Products include; Ice Cream, Cheesecakes, Fruit Pies, Fruit Danish, Puddings, Cakes, Croissants, Muffins, Quiche and Savoury Bakes.
The Company operates by two main principles: The first is to produce a range of food products to the highest possible standard and the second is to be an efficient, low cost producer, so that their products are priced within the reach of everyone. In this drive to reduce resource use the company embarked on a range of programs, one of which specifically examined energy consumption.
Initially a broad review of energy use at the factory was conducted to identify the areas of high consumption. This process highlighted the freezers as the main source of energy use and represented the greatest opportunity to make savings.
Sara Lee Bakery operates from a single site in Australia which is located just north of Sydney at Lisarow. Initially the raw materials are delivered to this site and stored in a central holding freezer. During the production process all products are frozen via a series of spiral freezers which are then immediately shipped off site to external freezer storage. The central holding freezer and the five spiral freezers are serviced by one large Ammonia refrigeration plant.
Changing the temperature without a reduction in Quality
The assessment of the possible savings from the refrigeration plant led to the set points of this plant to be raised while still allowing for the core temperature of the product to be within their Quality Assurance specifications.
The change involved raising the settings from -50 Kpa/ -45oC up to -37 Kpa/ -42oC.
This simple measure involved no capital outlay and ensured savings were to be gained immediately.
Other changes have been highlighted by this assessment which will involve some capital outlay and have a potential to save over $130,000 per annum.
Further Information on the AMC Industry Waste Minimisation Program and Additional Case Studies may be obtained by:
Phone: (02) 9209 4051, Fax (02) 9209 4470
