September 9, 2015
Volume 17 Issue 52
Prista Is Hot for Cold Blending
Bulgarian lube maker Prista Oil is upgrading the blending technology at its Ruse lubricants blending plant in Bulgaria, and hopes to persuade others to do likewise.
In the first phase of the upgrade, performed in June, the plant’s capacity of 110,000 metric tons per year was increased by 5,000 t/y. The company’s management expects additional capacity in the near future. “Our rationale was not so much to increase the plant’s capacity but rather to test and implement a new blending technology that gives excellent results compared to the traditional mechanical or in-line blending,” Milen Boychev, executive director of Prista Oil, told Lube Report.
In partnership with a Russian engineering team associated with Warsaw, Poland-based GQOil Innovation Europe, Prista now aims to promote CCBL – cavitation cold blending lubricants – technology in Europe. “It is a novel technology that can be simply described as imploding air bubbles in the cavitation zone that can mix the components on a molecular level,” Andrzej Chodyniecki, chief operating officer of GQOil, told Lube Report.
A key advantage is the reduced time and reduced temperature needed to accomplish mixing, according to Boychev. “Reduction of the time increases the throughput [volume], and reduction of the temperature decreases the energy costs. Both performance indicators are key factors for any lube blending process.” He added that the technology allows blending to be performed at about 20 degrees Celsius, versus the 40 to 60 degrees needed in conventional mixing processes.
In cavitation blending, base oils and additives go into a pre-mix tank and are mechanically stirred for 10 to 20 minutes. This “pre-mix” then is fed into the CCBL unit’s columns.
Here, the liquid is pumped at great velocity through a set of holes. As the moving liquid exits the holes under pressure, it releases air bubbles in the cavitation zone. These bubbles rapidly collapse due to the pressure of the surrounding oil, which generates a burst of energy that can be harnessed to disperse and homogenize the ingredients.
"The collapsed bubbles generate a jet of surrounding liquid but produce intense local heating, high pressures, and enormous heating and cooling rates also,” Chodyniecki related. The effect “takes a few microseconds and is on a micro-area level, so the temperature of the whole premix increases only by 2 or 3 degrees on the output side.” Any remaining bubbles move to the top of the liquid in the finished tank, mechanically mixing the components in the process of de-aeration. Finally, the batch in the finished product tank is ready for testing, storage and packaging without any additional mixing.
GQOil boasts that this process eliminates the need for reblends or corrections (i.e., additional blending because a finished product does not meet the target specification). “Normally this happens in low-volume, 10,000 ton per year or smaller mechanical blending plants, when producing small batches,” Chodyniecki said. “CCBL secures a better mixing process, and if dosage is made correctly, the finished lube results are perfect.
The equipment is not complicated to install and launch, said Prista, and is available in stationary and mobile versions. The mobile version is designed to fit into a 20-foot shipping container (or a 40-foot container including control room and lab), so it can be transported to smaller or off-shore sites. Prista is offering demonstration visits to potential users, and the partners are working to further develop the system as an integrated dosing and blending unit.
A report posted at GQOil Innovation’s website (http://www.gqoil.com/new/INDUSTRIAL%20TEST%20REPORT%202015.pdf) shows operational and quality data from actual batches of engine oil produced at Prista using CCBL. The tests, performed at the Bulgarian blender’s ISO 17025-certified laboratory, “proved that this technology and equipment secures smooth production and high blending efficiency,” the companies said.
GQOil added that its engineers have extensive experience in working with the mining and lubricant industry. The cavitation cold blending lubricants project was started as a prototype five years ago, and the concept dates to 2007, according to the company’s website.
Based in the Danube River port city Ruse, Bulgaria, Prista Oil is one of the biggest lube marketers in Eastern Europe. Its main business is lubricant and grease production, and it also manufactures LED lights and car batteries. The company has lube production facilities in Bulgaria, Turkey and Hungary. It also owns a blending plant in Uzbekistan, in a joint venture with the Uzbek state oil major Uzbekneftegaz.