CASE STUDY 3: Styrene Emission Reduction
Craft Fibreglass Ltd, Fairfield
Company Characteristics
Craft Fibreglass is a Corporate 3 member of the Composites Institute of Australia employing around 20 employees fabricating a range of custom design products.
The OH&S regulations set limits on worker exposure to styrene vapour in the workplace. Reduction of workplace styrene levels can be achieved by increasing ventilation or by reducing the emissions at the source. Increasing ventilation increases the emissions to the outside atmosphere whereas reduction at source reduces both workplace and environmental emission.
What did they do?
Changed moulding process
Craft Fibreglass needed to increase production and could not get enough skilled workers so looked for a technology answer. They also recognized that if they continued to operate in their existing manner they were likely to cause odour problems to their neighbours and draw attention of local regulatory authorities. Further, the company wanted to make the working environment better for their employees. They decided to tackle emission reduction at the source by changing from open hand lay up moulding to a closed moulding process using one of the several vacuum moulding process called Closed Cavity Bag Moulding or CCBM.
Benefits
Craft Fibreglass recognized the need to improve its workplace environment and make it a safer and more appealing place to work in. Installing mechanical exhaust ventilation would only increase environmental emissions outside the factory whereas the CCBM process would significantly reduce emissions both at the source in the workplace and therefore overall environmental emissions. This is in addition to increased throughput, readily accessible employees and reduced costs.
Controlling the quantity of resin used on a job and using vacuum to wet out the reinforcement reduces resin usage by 27% or $1.67 per square metre (based on a 2mm thick laminate).
Reduction in cycle times using CCBM resulted in greater productivity and more efficient use of labour thereby reducing labour costs per moulded item.
As the employees are not getting their "hands dirty" and do not need the skills of a hand laminator they are easier to hire, train and retain.
What are the Outcomes?
Cost of setting up CCBM including License fee and equipment is around $15,000
The only other costs are reusable silicone bags which including labour is approximately $300 per square metre.
The following gains were made in production of products using CCBM.
· Styrene Emissions reduced by 68%
· Resin Usage reduced by 27%
· Waste reduced by 1%
· Labour reduced by 15 - 20%
· Cycle time reduced by 33%
Financial Benefit
Based on a monthly resin usage of 500 kg a month at $3.10/kg and employing 5 laminators instead of 6 the saving over a year is:
$5022 in resin usage and $30, 0000 in labour.
Therefore the payback period is around 6 months.
Where to Now?
Craft Fibreglass will continue to use CCBM for products that it is suitable for and seek to develop new uses.
Composites Institute of Australia Model EMP Case Study #3
WORKSHEET 6 - STYRENE EMISSION FROM OPEN MOULDING PROCESESS
CCBM vs Hand Lay-up
Process / Resin / Styrene Content % / Application Method / Suppression / Emission factor / Quantity Used kg/y / Emission kg/yCanoe / Body / 40 / Hand Lay-up / None / 6.2 / 6000 / 372
Canoe / Body / 40 / CCBM / None / 2.0 / 6000 / 120
Procedure:
- State process
- State Type of Resin
- Select Styrene Content from Table
- Select Application Method
- Select Non-Vapour Suppressed or Vapour Suppressed
- Find correct Emission Factor from Table W6a
- Find Quantity of resin used in the process in kg/year
- Calculate Styrene Emission from Process
Calculation:
Styrene Emission kg/y = Resin Use kg/y X Emission Factor/100
Process / Total EmissionCanoe / Spray-up / 372
Canoe / CCBM / 120
Difference / 252
% Decrease / 67.7
Composites Institute of Australia Model EMP Case Study #3