20 ENERGY SAVING TIPS

Hammer Mill

The new generation of large diameter hammer mills uses significantly less electricity with the same grinding result than the older generation of small diameter hammer mills. An average energy saving of 15 to 20% is possible with a fine structure.

The application of a frequency-controlled hammer mill.• One can adjust the speed of the motor to the

recipe and the desired structure after grinding. This may lead to an energy saving of 4%.

• A frequency control can also be used to reduce the starting current by which a smaller power connection is required.

• The peak current becomes limited and therefore cost saving.

• Time can be saved by shorter stop times.• Lost energy from frequency control can be

used for energy generation (Low Harmonic).

By matching the screen perforation perfectly to the required structure of the formula energy can be saved. The application of a 3 mm perforation instead of a 2,5 mm perforation may yield a saving up to 20%. By equipping the hammer mill with an automatic screen exchange, screens can be exchanged quickly and easily while the hammer mill is running stationary between two batches, preventing down time of the hammer mill.

Timely replacement of the worn hammers and sieves results in optimal hammer mill settings and thereby saving energy.

In these times of rising energy prices, shortage of resources, emissions targets and changing legislation the compound feed industry is challenged with limiting energy consumption.

In feed mills the pelleting and grinding processes consume the most energy. Optimizing these processes has an immediate effect on energy consumption. But there are many more ways to save energy in your feed mill.

We are pleased to present 20 energy saving tips and a checklist that might be useful in determining energy saving opportunities in your feed mill.

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Grinding and Mixing

Grinding and mixing process

Sieving of the fine ingredients before grinding may result in an energy saving of up to 5 % as these components do not need to be ground.

Singular as opposed to multiple grinding leads to an improved quality of ground product and at the same time an energy saving up to 20% because of an optimal use of the hammer mill (larger batches and less idle time). Singular grinding requires though an investment in extra storage silos.

By putting a pre mixer before the hammer mill, a more even load in the hammer mill is achieved which in turn leads to a saving in time and thus energy.

Limiting contamination in the mixers may quickly lead to a saving in energy up to 20%. The contamination of the mixers can be limited by applying separate liquid mixers.

Grinding and Mixing

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Counter flow coolers are more energy efficient than belt coolers and take up less space.

Applying frequency controlled fans may lead to an energy saving of up to 20%. Frequency controlled fans enable adjustment of the air quantity to variable conditions.

Cooling

The pelleting process requires 60-65 % of the energy consumption in a compound feed mill. Energy can be saved by optimizing the pelleting process.

Conditioning

A long term conditioning of the steam treated feed by the LTV can lead to an energy saving of up to 20%. During conditioning, moisture diffuses deeper in the feed meal and makes the meal better deformable. Less mechanical energy is required for a good quality uniform pellet.

Pellet mill

The higher the demand for a good pellet quality the higher the energy consumption and roller and die wearage. The correct choice of PDI (= pellet durability index) can provide a saving in energy.

The application of automatic roller adjustment. By retracting the rollers while idle, energy can be saved and at the same time the lifetime of the rollers and the die increases.

Application of a frequency control to limit starting current and optimize the die speed.

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Pelleting Process

Automatic process control

An extensive automation of process control and management can result in saving energy. The factors that play a role are:• Limiting idle time.• Optimizing settings and operation.• Better preventive maintenance.• Timely cleaning of the mixers and pelleting line

Stimulating consciousness about energy saving measures The operators determine to a large extent the exact settings and operation of the feed mill. Preventing idle time and down time of machines, switch off transport systems, machines, lighting, heating and ventilation when not in use can save a lot of energy. Training operators and making them conscious about their role in applying energy saving measures may make a difference of a few percentages

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Drive system

Primarily energy can be saved with the application of high efficiency drives (IE3).

Transport equipment

From an energy consumption point of view, mechanical transport systems are preferred over pneumatic systems. The energy consumption of pneumatic systems is 2 to 5 times higher. Pneumatic systems may be chosen for minimizing contamination risks.

Compressed air system

The application of an advanced modular compressed air system prevents leakage and creates an optimal flow. This may lead to a saving in energy of up to 30%.

Preventive maintenance

Timely replacement of worn components and of the dies in the pellet mill results in optimal machine settings and thereby saving energy.

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Check List

Heelderweg 11 6097 EW Panheel | P.O. Box 5010 6097 ZG Heel | The Netherlands | Phone +31 (0)475 579 444 | Fax +31 (0)475 579 223 | info@aarsen.com | www.aarsen.com

This checklist can help you to determine to what extent energy saving measures have been taken in your compound feed factory!

To define the optimal set of measures for energy efficiency it is important to take into account all relevant parameters of the feed milling process and the formulas produced.

Our representatives will gladly help you to define the best solution for the specific requirements of your feed mill production process.

The saving percentages mentioned in this sheet are indicative and for average situations. Sources: Information magazine compound feed industry – InfoMil – The NetherlandsExperience and data from worldwide installed feed mills – Van Aarsen International – the Netherlands

Applicable to existing installation

Applicable for replacements

and new constructions

Grinding and MixingIs a large diameter hammer mill used with big breaker plates (new generation hammer mill)?

X

Is the hammer mill frequency controlled? XCan sieves with larger perforations quick and easy be applied? XAre the hammers and sieves timely replaced? XIs the product sieved before it enters the hammer mill? XIs the product pre-mixed before it enters the hammer mill? XIs the product singular ground (pre-grinding)? XAre the mixers cleaned regularly? XAre separate liquid mixers applied? X

Pelleting processIs long term conditioning applied in the pelleting process? XIs the PDI determined and controlled? XDoes the pellet mill have an automatic roller adjustment system? XAre the dies timely replaced? XIs the pellet press cleaned regularly? XAre counter flow coolers used? XIs the cooling fan frequency controlled? X

Drive systemAre high efficiency motors applied? X

Transport equipmentIs a completely mechanical transport system applied? X

Compressed air systemDo you have an advanced compressed air system? X

Process controlIs the process control automation system tuned? XIs attention paid to stimulating consciousness about energy savings of your operators? X