Frequently Asked Questions

Below is a list of commonly asked questions from customers.

Using the links below, see if you can find an answer to your question.

If not, feel free to Contact Us


The keg has a weight of 1.25kg.

The Dolium® kegs are 100% recyclable. The environmental impact of Dolium® kegs when compared to stainless steel kegs is much lower.

Dolium PET keg Environmental Impact


The maximum working pressure is 3,5 bar (50 psi) which is equal to stainless steel kegs.

The Dolium® kegs remain functional up to 5,0 bar. The Pressure Relief Valve (PRV) opens at 5,2 bar (+/- 0,2). For more details see PRV.

Dolium PET keg Working Pressures

The technical shelf life, in compliance with the brewer's specifications, is proven to be 6 months. This is equal to stainless steel kegs.

PET : Polyethylene terephthalate is a resin used for injection stretch blow moulding of bottles and containers for food and beverage. This is the basic resin for the Dolium® keg body.

HD-PE : High Density Polyethylene is a resin used for injection moulding of plastic parts. This is the basic resin for the Dolium® keg's top and bottom.

The Dolium® body is composed of Invista® PET Polyshield® blended with 5% of MXD6 Polyamide.

The polyshield component contains the oxygen (O2) active barrier, keeping the oxygen away from the product, whilst the MXD6 Polyamide is responsible for blocking the CO2 from leaving the keg.

The average loss of CO2 is 0.05gr/30L/month. For the oxygen content present in the keg over time please refer the graph below:

Dolium PET keg O2 PPB Chart

The monolayer keg wall is blended with a specific amber colour which is protecting beer in the frequency range of 300-450 nm which is the UV sensitive range for hops resulting in light struck off-flavours.

Dolium PET keg UV Protection Chart

DOLIUM® kegs have a lifetime of 600 days, determined by the active oxygen scavenger that is built into the monolayer wall of the kegs. These corresponding 20 months start at the day of preform production as during the injection moulding process this O2 barrier gets activated.

DOLIUM® brings the new empty kegs on the market within the next month, as bodies are blow moulded and kegs assembled within a few days prior to delivery.

The pallet label indicates the 'BEST FILL BEFORE DATE' which is formatted in 'MONTH + YEAR'. This timeline of about 6 months guarantees the brewer/filler the beverage shelf-life of at least another 12 months. The earlier the filling, the longer the guaranteed beverage shelf-life is.

Experience suggests that an additional period of 100 days is feasible but can't be guaranteed by the resin manufacturer and as such not by DOLIUM®.

Dolium PET keg Pallet Label
Dolium PET keg Best Before Date Graph

Filling and Tapping

Dolium® kegs are available in 30 liter (7.93 US gallons) and 20 liter (5.28 US gallons) volumes.

Dolium® kegs are equipped with either:

  • S type spear=Sankey, well type or European Sankey type
  • D type spear=Draft, American Sankey type
  • A type spear=Alumasc, Flat type
  • G type spear=Grundy, Trilobe type
Dolium PET keg Fittings

For all spear types the connection process is equivalent to stainless steel kegs.

The Dolium® kegs can run on manual, semi-automatic, full-automatic, in-line and rotative filling lines.

Each filling line can differ from another. We can provide you with more technical details on request.

Dolium® can also provide samples for qualifying brewers for testing purposes.

Please Contact Us for more information.

No internal cleaning required. Our customers receive clean and sealed kegs. The Dolium® keg is assembled using clean and sterile components in a clean room environment.

We recommend to rinse the outer spear parts by use of hot water (85°C for 2 seconds) or clean water (peracetic acid or chlorine dioxide) prior to opening the valve system.

Yes. Our customers receive CO2 pre-flushed and CO2 pressurized kegs.

Dolium® guarantees a CO2 concentration above 90%.

Therefore a final CO2 flush is required on the filling line prior to filling equal to practice with stainless steel kegs.

No, the Dolium® kegs can run on manual, semi-automatic, full-automatic, in-line and rotative filling lines at filling speeds equivalent to stainless steel kegs.

Dolium® kegs can be filled manually in straight up position or upside down equal to stainless steel kegs. For detailed instructions please Contact Us.

For detailed descriptions of pressure and temperature settings please Contact Us or consult our Handling & Safety instructions.

Dolium® kegs are delivered CO2 pressurized, a pressure test is recommended.

No cleaning or disinfection activity is required. A CO2 flush is still mandatory prior to filling.

Ensure that Dolium® kegs never get into contact with caustic soda or alkaline detergent solutions (a.o. lye, alkaline chlorine solutions, tensides) as PET is not compatible with these type of products.

The Dolium® keg is designed for a head space of minimum 2% of the nominal volume.

Please keep the beverage pressure below 3 bar with a minimum pressure difference of 1 bar between in and out.

Yes, the working temperature of the Dolium® keg is set between 0°C and 35°C.

Please check our Handling & Safety instructions.

Beverages packed in stainless steel kegs are always at their best being drafted and consumed as fresh as possible.

We promote the same for Dolium® kegs. A maximum period of 30 days should be targeted for using kegs and draft.

Once the keg has been emptied and disconnected it is still filled with CO2 gas under pressure.

Therefore we recommend depressurizing the keg as soon as possible in a well-ventilated area.

The depressurization procedure is simple and can be be done by turning the Pressure Relief Valve by 90 degrees with a flat head screwdriver.

Please check the neck carrier on the keg or our Handling & Safety instructions for a detailed description.

Once the keg is depressurized, you can break down the plastic by crushing, cutting or shredding.

Never put the keg outside as domestic waste! Once the keg is depressurized, it should be recollected, brought into the recycling circuit.


Please contact our sales team at for a quotation.

The minimum order is 1 pallet. 1 pallet of 30L Dolium® kegs contains 44 kegs. 1 pallet of 20L Dolium® kegs contains 55 kegs.

When your kegs are rotating 1-4 times a year, the Dolium® one-way PET keg becomes the most efficient option.

Dolium PET keg Efficiency Chart

Dolium® kegs are more efficient than stainless steel kegs because of:

  • High long distance transport costs on two way stainless steel kegs
  • High loss of stainless steel kegs due to theft or damage
  • High Capex investments in stainless steel keg renewals
  • High Capex investments in stainless steel keg to cover the volume growth
  • High Capex investments during seasonal peak volumes

Please contact our sales team at and we will be happy to connect you with the proper distributor or to process your request directly ourselves.

For qualifying brewers we have a program in place to provide free samples for testing purposes.

Dolium® kegs have the flexibility and compatibility required to fill manually or automatically.

If you are interested in testing the compatibility for your system please contact us for further details at

With manufacturing in Belgium and distribution throughout the globe, we can meet your needs no matter the country you are in.

Please contact so we can best assist you.

Products by:

Dispack-Projects NV

Production Warehouse:
  • Dispack-Projects
  • Vosseschijnstraat 192 A
  • 2030 Antwerpen
  • Belgium
  • EU



Find us on:

Facebook icon Twitter icon Instagram icon