Print page

Email page

PET bottle manufacturing

Q: We are a small bottling facility and bottled water company located in a pristine part of the country. We wish to expand our bottling facility and add a Nissei two-stage injection and blow molding system on site. Our goal is to control our manufacturing process so that we can become competitive and self contained. To achieve our goal, we must expand our existing plant facility. One of the requirements that the county planners are asking us to provide prior to granting us permission to proceed is confirmation that our PET injection and blow molding process will not contaminate the surrounding environment. I am having a hard time finding some kind a report or data on PET bottle manufacturing and the environment. All I can find is information on the recycling process. Can you provide information on the subject?

A: In establishing your PET blow molding center, you have about 3 challenges where you can be tripped up.

1. Air Emissions
2. solid waste/hazardous waste/cleaning compounds
3. Water emissions.

The source of your air emissions will be fume and dust and off gassing from the blow molding process. The data on that should come from the molding equipment manufacturer. You may also have a source of heat (additional boiler emissions or gas) that needs to be included in your emission calculations you submit to the air board.

The second thing is the water emissions. You are using a CIP system for your process water, or should be if you are not, and that represents no change, except in capacity. I assume that you are discharging to a sewer and do not have a separate state permit. Even if you have a separate permit, the calculations are primarily for increases in cooling water and cleaning from the CIP. You will have to address the effluent quality with the CIP equipment manufacturer, or sample before and estimate the increases and changes from the projected chemical increases. One thing to watch out for is potential toxic discharges from your disinfectants. You may have to consult with the sewer board to get a list of what they prohibit.

The third thing is the solid/hazardous waste stream. You will have plastics that you will collect and recycle back to the supplier. You will have floor dusts from cutting and trimming operations, which you can demonstrate are non hazardous by obtaining the MSDS from the supplier for the PET. Then, you will have grease and oils which you will collect and dispose of in accordance with the local regulations, along with your maintenance shop wastes. Pay attention to your solvent usage and make sure that it is handled as a hazardous waste if it contains chlorinated compounds. There should be no problem there if you recycle and use a good service for lube oils and maintenance materials.

The final problem you will have is writing that all down. If I can be of assistance in helping with the calculations, please let me know.