Also motor oils and gasoline proceed toward the Washer Machine infeed, hidden into returned bottles

    Also motor oils and gasoline proceed toward the Washer Machine infeed, hidden into returned bottles

It is a fact: when bottles are urgently needed, also glass returnable bottles born to host beer or mineral water, can fulfill their basic purpose of container for liquids of completely different nature.   Out of the Bottling Plant its glass and PRB returnable bottles can in reality encounter a use to contain mineral oils, like the motor oil,  petrol, gasoline and other hydrocarbons.  The consequences of a seeminlgy innocent act, without an electronic device capable to detect hydrocarbons before these bottles reach the Filler Machine, can affect severely the health of the people later ingesting those hydrocarbons.  Worldwide press shows plenty of these news, on a daily base.  

Oil-beverage mix prevention

Mineral oils whose level over the bottles' base top of the inner convexity amounts to (5 – 10) mm, can be detected by a specific inspection part of the Empty Bottle Inspector.  How many millimeters, how many milliliters, strictly depends on the glass (or, PRB):

  • thickness;
  • transparency to the infrared portion of the em spectra;
  • linear speed of the bottle, slower Lines allow more time to integrate measurements arising by a single bottle.                     

For this purpose, the illuminator of the bottle Base inspection, an array of LEDs or a strobo flasher, encounters a second use as source of light for the IR Residual Liquid Control. An additional IR sensor, intercepts and convert in electric signal a portion of the light pulse directed toward the Base inspection CCD or CMOS-camera. The signal is then amplified and digitised, then resulting normalized in a desired range, quite commonly 4096 bit wide.  This result is then compared to the limit values the Service Technician has to set for the IR Residual Control inspection, during the commissioning of the Empty Bottle Inspector.  

  Benzene oxide molecule. One of the most frequently oils whose traces are encountered into returned bottles (picture Jynto/CC0 1.0)

Differences greater than the reject threshold referred to non-defective bottles, shall control the rejection of the container toward one of two mutually alternative way out:

  • automatic destruction, in a bin;
  • return to Bottle Washer Machine, for a second attempt to wash the bottle.

 A sight into one an EBI optoelectronics cabinet. The illuminator of the bottle Base inspection (an array of LEDs or a strobo flasher, like in this case), encounters a second use as source of light for the IR Residual Liquid Control. A sensor sensible to the infrared portion of the spectra, intercepts part of the photons and converts them in electric signal.  The signal, then amplified and digitised, results finally normalized in a desired range and compared with a set range.

 Marked yellow the infrared band of the entire electromagnetic spectrum, comprised between visible ultraviolet UV and microwaves

Layout remarks

A bottle with mineral oil into should not enter at all into any Bottle Washer Machine.  If, on the opposite, it enters the Washer Machine, this results in contamination of the inner water.  Contamination later well visible as an iridescent effect over the external sidewall of thousands of bottles.   This, meaning that a relatively small amount of mineral oil, e.g. 200 ml, is yet enough to leave a truly negative memory of its passage to many thousands of following bottles.   As a consequence, the correct destination for the Infrared Residual Liquid Control rejects is toward the automatic destruction, e.g. jointly with the Finish inspection rejects, rather then a return to the Bottle Washer Machine.  But, in general, there is always the possibility that several inspections part of  the Empty Bottle Inspector separately detect a defect in a single bottle.  An example arises by the case when a massive amount of water-based residual liquid lies into the bottle. 


 Droplets of motor oil of mineral origin suspended into water.  Returnable bottles following special temporary necessities can fulfill their most basic purpose of container, terminating filled with hydrocarbons 

like this where the measurement of the information is affected by poor Specificity.   This shall force in the end the Bottler in a closed vicious circle.   These bottles filled with so much water and soda, are clear markers of plastic foils and papers jamming the out feeds of water by the bottles, where these are purportedly tilted upside down to empty and rinse them in the Bottle Washer Machine. The example above meant to remember that the Empty Bottle Inspector is a complex Expert System born to prevent extreme undesidered consequences to final Customers; but not the best way to help to, namely, posticipate the due ordinary maintenance of the Washer.  

E.g., a bottle whose capacity is 330 ml, reaching the EBI by the Washer Machine filled with 250 ml of (hot) water and caustic soda, shall be  also considered a defect.  High Frequency Residual liquid control.   Then, two separate inspections shall intervene requesting a reject, and not only the Infrared Residual Liquid control we are  here treating.   The common outfeed for a bottle with water and soda into is surely the Bottle Washer but not for the Infrared Residual Liquid control, as we saw. This bottle shall surely be sent to Bottle Washer, in contradiction with the rule to prevent bottles with mineral oils from entering the Bottle Washer Machine.  Simply: there are too many cases  

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This website has no affiliation with, endorsement, sponsorship, or support of Heuft Systemtechnik GmbH, MingJia Packaging Inspection Tech Co., Pressco Technology Inc., miho Inspektionsysteme GmbH, Krones AG, KHS GmbH, Bbull Technology, Industrial Dynamics Co., FT System srl, Cognex Co., ICS Inex Inspection Systems, Mettler-Toledo Inc., Logics & Controls srl, Symplex Vision Systems GmbH, Teledyne Dalsa Inc., Microscan Systems Inc., Andor Technology plc, Newton Research Labs Inc., Basler AG, Datalogic SpA, Sidel AG, Matrox Electronics Systems Ltd.

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