PROCESSING & TECHNOLOGY Nanocavitation: a …

1 TECHNOLOGY developed by Cavitation TechnologyInc (CTI), USA, and introduced to the oils andfats PROCESSING industry by Belgium s DesmetBallestra. It has been proven to increase oilyield and substantially reduce the chemicalsrequired to produce refined vegetable oil whilemaintaining, and even improving, oil heart of the TECHNOLOGY is theNanocavitation reactor. A nano reactor is a sta-tic device with no moving parts (see Figure 1,Most vegetable oils need to berefined to render them more suit-able for their final use, be it humanconsumption or industrial use. Themain components to be removedare the free fatty acids (FFAs) and phospho-lipids.)

2 They are usually removed by applying acaustic soda and acid treatment in neutralisa-tion and degumming, respectively. Apart from these main unwanted oily sub-stances, other minor components are alsoremoved in the last decades, some importantimprovements have been introduced in oiltreatment processes. Improved mixing of chem-icals in caustic soda and acid treatment usingultra high shear mixers, and the introduction ofenzymes (phospholipases) to specifically attackthe gums, have substantially improved the effi-ciency of these wet oil treatment processes. Today, a modern neutralising plant can pro-duce oil with less than FFAs and less than5ppm in phospholipids in the oil exiting theplant.

3 The use of computer-controlled instrumentsand the development of better performing cen-trifugal separators have further helped vegetableoil refiners to better control their operation,decreasing their operating costs and improvingoil yields. However, the basic process hasremained unchanged for several cavitation has now found its way intothese processes and the first industrial applica-tion, nano neutralisation, is being commer-cialised neutralisation is a real novel, patented? OFI AUGUST/SEPTEMBER 2012 & TECHNOLOGYNano neutralisation is a noveltechnology which increases oilyield while substantially reducingthe chemicals required toproduce refined vegetable Marc Kellens explains theprocess behind the technologyNanocavitation: aproven newconceptabove).

4 Its name is derived by the creation ofnanometer-sized bubbles that are formed whilethe fluid is pumped through the nano reactorunder high pressure, creating an intense hydro-dynamic physical and chemical actions actu-ally take place in the nano reactor is not yetfully understood, but its effect is amazing. Crude vegetable oil is pumped through aseries of scientifically designed geometries. FIGURE 2: TYPICAL NANO NEUTRALISATION PROCESS FLOW DIAGRAMFIGURE 1: COMPUTER IMAGE OF A NANO REACTOR (INTERNAL)Source: Cavitation TECHNOLOGY IncSource: Desmet Ballestra OFI AUGUST/SEPTEMBER 2012 each stage, there is a dramatic pressuredrop.

5 The water molecules in the oil vaporiseand recompress to a liquid at each stage, creat-ing shockwaves that break the phospholipidmicelles to their molecular level and, hence,make the non-hydratable phospholipids morehydratable. In addition to that, the nano reactor thor-oughly mixes the acid and caustic soda solu-tions that have been added to the crudevegetable oil to a level that even the best highshear mixer cannot nano reactor can be installed in any exist-ing neutralisation process with relative ease andat minimal cost. A typical nano neutralisationprocess flow diagram is shown in Figure 2 (pre-vious page).

6 The temperature of the crude vegetable oilonly needs to be heated to 40-60 C instead of80-90 C typically needed for acid fluid pressure before the nano reactor canreach up to 100 barg, but typically it operatesbetween 60-70 barg. Results and benefitsNano neutralisation has been found to substan-tially reduce chemical consumption. The acidthat is normally used to chemically cleave thecalcium (Ca)/Magnesium (Mg) metals from thenon-hydratable phospholipids is nearly elimi-nated. With no need to neutralise excess phos-phoric or citric acid, and with the outstandingmixing in the nano reactor, the quantity ofcaustic soda required to neutralise the FFAsfalls even below reducing excess caustic soda, there is lesssaponification of oil into soap and a muchcleaner separation in the centrifugal results in a valuable increase in oil yield asless neutral oil passes with the soapstock.

7 The cleaner separation also results in lesssoap remaining in the oil exiting the soap sepa-rator. Less soap in the oil reduces the amount ofsilica or water wash needed to remove the soapsprior to at several separate commercial instal-lations in the USA have shown it is possible tocompletely eliminate the need for acid treat-ment when PROCESSING either crude non-degummed or crude degummed soyabean oil. Inall cases, a phosphorous level below 10 ppm,even less than 5ppm, was achieved. The nano reactor allowed the caustic sodaaddition to be reduced by 30-50%. The soaps offthe neutralising centrifuge were below 150 ppm(see Table 1, above).

8 In addition to the acid and caustic soda sav-ings, both industrial trials gave significantimprovements in oil yield. The oil yieldimprovement has been found to be above , in some cases, greater than 1%.A commercial installation that is processingPROCESSING & TECHN0 LOGY approximately 20 tonnes/hour of crude waterdegummed soyabean oil has been operating anano reactor since early 2011. There have beensavings in phosphoric acid, caustic soda and sil-ica. The plant is currently using approximately90% less phosphoric acid and 50% less causticsoda than before the nano reactor was addition, the silica addition has beenreduced to nil.

9 But most significant in terms ofsavings was the gain in refined oil yield ofaround %.The choice to go for a nano reactor in oilneutralising is driven by its economic on top of that, it has also been shown to bemore forgiving on incoming oil quality. Thisallows a smoother operation and more consis-tent oil quality output. The monthly savings ofa refinery with a nano reactor are shown inTable 2 (left).Using a nano reactor in a vegetable oil refin-ery provides several other benefits. The sub-stantial chemical savings are better for theenvironment, adding another significant eco-nomic benefit.

10 Crude vegetable oil processedthrough a nano reactor allows the neutralisa-tion centrifuge to operate more smoothly sincethe separation line between the light and heavyphase is more defined. Other nano cavitation applicationsWith the results obtained in nano neutralisa-tion far exceeding expectations, the focus todayis on the degumming process. Comparable ben-efits are to be expected here as the list of nano cavitation applications inoil PROCESSING will become even longer the morethe working principle of this unique and trulyrevolutionary TECHNOLOGY is revealed. Moreresearch and science behind this technologywill help us to better understand the processand hence its potentials: a real challenge forevery scientist and plant operator.