Green Business - Environmental Protection Agency - Case Study on Sturdy Products


Aims of this project

Sturdy Products Ltd. is a private limited company which employs approximately 50 people from its base in Blessington, Co. Wicklow.  Sturdy Products manufactures rotationally moulded plastic products.  The aims of the project were to convert the supply of the company's primary raw material from 20 kg bags to a bulk supply, and to implement heat recovery from the manufacturing plant to supplement the office heating system.

Sturdy Products uses in excess of 900 tonnes of polyethylene raw material per annum. This powder material was delivered in convenient, accurately measured 20 kg bags which were manually emptied into the mixing process where other ingredients were added depending on the product being manufactured.  The main aim of this project was to eliminate the use of the 20 kg bag by switching to one tonne bulk bag supply with automated dispensing.

Project description

Existing processes were examined with the main areas of concern identified as handling the raw material, dispensing into the mixing tanks and adding the colour powder. The project identified one tonne flexible intermediate bulk containers (FIBCs) as the most appropriate form of bulk supply, although it remained vital to ensure an accurate quantity of powder in the mixing process.

The project involved the on-site development and testing of a prototype system. Once this system was proven, material handling systems to carry the bulk bags and an electronic control system to automate the powder dispensing process from the FIBC via a valve and load cell were installed at the site. Suitable racking was installed in the storage area to accommodate the FIBCs.

The heat recovery element to the project involved ducting air from the moulding machines and the installation of a simple heat exchanger to preheat the water of the office central heating system.  The system can alternatively filter the heated air and use it directly for space heating of other areas in the production building.

Achievements and lessons

The company has converted the supply of all its polyethylene powder over to the reusable FIBCs and has completely eliminated the 20 kg bags. The costs associated with their disposal have also been eliminated.

The new dispensing system is more efficient and less labour intensive than the previous method. The successful implementation of the project has resulted in the following annual savings:

  • 45,000 disposable bags eliminated from the solid waste stream saving €2,000 waste costs.
  • Switching to bulk supply saved 2.5% of material costs corresponding to €16,000.
  • Annual labour savings of €3,430.
  • Eliminated waste disposal costs of €2,000.


The initial plan was to install one automated dispensing system in the primary mixing area of the factory, but this has been expanded to include two additional automated dispensing systems in other mixing areas of the factory.

This project was carried out by

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