Collecting or Processing Waste Oil? Perhaps Propak can help you!

Propak can design and supply waste oil conversion units, which will produce, either fuel oil or Number 2 oil (diesel). These units are skid mounted for easy transport and field installation. Propak can offer a choice of several designs and capacities.

Of the 2.4 billion gallons of lubricating oil used per year in the U.S. alone, thirty three percent (33%) is burned in industrial heaters without being upgraded while 60% is dumped, incinerated or consumed. Only 7% is reprocessed back to lubricating oil due to low consumer acceptance. Some companies that operate used oil reprocessing plants use a simple thermal cracking process. The process partially cracks the feedstock and yields a highly unstable low-grade fuel oil, which can be corrosive, tarry, and discolored along with a characteristically foul odor. All of these factors decrease the overall marketability of the product, thereby reducing the incentive to reprocess used oils. By improving the quality and marketability of gasoil derived from used oils, the ROBYS™ process enables the thermal cracking of used oil to gasoil products such as diesel fuel and heating oil to exist as a profitable alternative to existing methods of used oil disposal. The ROBYS™ technology is a relatively low cost, modular gasoil stabilization and purification process. It can stand alone and be added to an existing plant or it can be integrated into a complete thermal cracking plant design. The high olefin content of thermally cracked gasoils contributes to instability and gum formation. Foul odor, dark color, and acidity are all characteristic of nitrogen, sulfur, and chlorine compounds present in the gasoil. Figure 1 illustrates the color comparison between untreated gasoil derived from thermal cracking and the same gasoil treated using the. ROBYS™ system.

The ROBYS™ process has been integrated into the design of proven refinery caliber used oil thermal cracking systems that have been developed by others. Figure 2 shows the ROBYS™ system's place in a typical thermal cracking plant. Complete used oil thermal cracking plants incorporating the ROBYS™ process are available and can be constructed in modules to produce gasoil in the range of 30,000 metric tons per year input capacity and greater. Propak Systems Ltd. of Calgary, Alberta, Canada manufactures such used oil plant design under license from the developer of the thermal cracker, Great Northern Processing Inc. (GNP).

Fuel Oil Purification & Stabilization

The ROBYS™ Process" purifies and stabilizes reclaimed and refined fuel oils. ROBYS™ is designed as an add-on unit to waste oil recycling and petroleum refining operations.

What's Special about ROBYS™?

The ROBYS™ process can produce fuel oils that:

• are not odorous (foul smelling)
• meet regulatory and consumer color criteria
• minimize the formation of gums and tars during storage
• are not highly acidic

One of the great advantages of the ROBYS™ process Is that it can be designed as a stand-alone fuel purification and stabilization process. It can be skid-mounted and installed in plants with minimum interruption to production. Since the ROBYS™ process is an independent purification unit that treats the product steam, it can be adapted to other applications where hydrocarbons need to be purified and stabilized.

Odour and Colour

Several processes on the market attempt to convert waste oils into fuels. But without ROBYS™, their partially processed or final products often contain compounds that cause foul odours. A relatively rapid deterioration of products, also causes them to become darker in colour, which makes them even less marketable.

Gums and Tars

In some processes, waste oils are cracked at high temperatures so that the product oils are rich in olefins. Olefins cause instability in the resulting fuel oil; they tend to polymerize and form tarry deposits that impair equipment by plugging pumps, lines, and burner tips. This, in turn, causes maintenance problems, plant and equipment downtime, fuel wastage and incomplete combustion. The ROBYS™ process can eliminate these problems.

Acids

Acids cause thermally cracked waste oils to be corrosive and excessively high acid numbers fail the ASTM criteria for fuels. Normal waste-oil conversion processes seldom deal effectively with the large amounts of acid present in the reprocessed fuel.

ROBYS™, however, substantially reduces the content of sulphur, nitrogen, and chlorine, the very elements that give rise to all the acids. That reduction also accounts for the absence of malodour from fuel oils that have been through the ROBYS™ process.

For most waste-derived fuels, the above-mentioned factors limit markets and lower their value. Therefore, ROBYS™, a process that purifies and stabilizes waste-derived fuels, can increase their marketability.

Improved Economics of Waste-Oil Reprocessing

The ROBYS™ process has great potential to improve the economics of waste-oil reprocessing and possibly to replace conventional methods of stabilizing fuels and oils.

The process effectively and economically stabilizes and purifies fuel oil. Through this process, acids, odour and precipitates are very much reduced. So also are sulphur, chlorine and nitrogen compounds.