Biodiesel is an organic, renewable alternative to conventional diesel fuel. It is environmentally friendly due to lower emissions and usable in current engines designed to operate on diesel fuel.
The transesterification process converts organic fats and oils into biodiesel. In other words, transesterification is the process of converting fats into biodiesel and glycerin. Methanol and lye being the catalysts in the process. The lipids are animal fat or used vegetable oil.
A biodiesel centrifuge uses a high g-force of 8,000 Gs to separate biodiesel from glycerin. The centrifuge bowl rotates at 7,000 RPM. The centrifugal force spins out the denser glycerin to discharge out the heavy phase outlet. The lighter biodiesel discharges through the biodiesel chamber outlet.
A small 'self-cleaning' centrifuge is able to separate 10 GPM of biodiesel and 5 GPM of hot WVO.
The following are key advantages of centrifuges in biodiesel production.
The biodiesel production process uses industrial centrifuges in most of the production steps. The list below explains each step with the corresponding centrifuge application.
Post reaction is essential to separate the two immiscible liquid phases (biodiesel and glycerol) to get pure biodiesel. It is critical to remove all traces of glycerol and any sediment to reduce the load on the next process step.
Industrial centrifuges are a proven way to separate the two liquids at this stage. Alfa Laval industrial centrifuges (disc-stack type) generate a high centrifugal force on the fluid. This force separates the glycerol from the biodiesel to produce ASTM grade biodiesel. Especially in cases where virgin vegetable oils are the feedstock.
Biodiesel produced using WVO or animal fat needs a further step to remove any remaining impurities. A simple water wash polishes the biodiesel to ASTM purity level.
An industrial centrifuge is the best fit for the separation of wash water from biodiesel. High centrifugal force in the disc stack centrifuge separates the water from biodiesel. This separation is, again, a continuous, efficient process.
Polishing the biodiesel removes tiny particulate matter from the finished biodiesel. In the case of water wash, trace amounts of water may still be present in the biodiesel. The centrifuge removes the water from the biodiesel at this polishing stage.
Distilling separated glycerol recovers the methanol and produces glycerin. Pure glycerin has good resale value and is demand in the food and cosmetics industries.
Clarification of glycerin to remove small impurities makes it usable. A disc stack centrifuge has the required g-force to remove the finest trace particles from glycerin.
The advantages of using industrial centrifuges (listed above) are applicable for glycerin purification as well.
Biodiesel production requires the use of methanol. This requirement, in turn, needs unique manufacturing specifications. Biodiesel centrifuge systems manufactured by Dolphin Centrifuge have the following features. We refer to these features as the ‘Biodiesel Kit.’
| Centrifuge Type | Alfa Laval Disc Stack Centrifuge with Biodiesel Kit | ||
| Model | BDB 104 | BDPX 207 | BDB 209 |
| Sludge Handling | Manual Clean | Self-Cleaning | Manual Clean |
| Biodiesel Kit Features | Compatible Elastomer, Corrosion Resistant Top-coat, Friction Clutch Replacement, Motor Suitable for Hazardous Applications | ||
| Capacity | |||
| Titrated WVO Stock | 3 GPM | 10 GPM | 35 GPM |
| Glycerin Separation | 6 GPM | 18 GPM | 60 GPM |
| Wash-Water | 3 GPM | 10 GPM | 35 GPM |
| Glycerin Clarification | 5 GPM | Not Suitable | 40 GPM |
| Motor | 2 HP | 10 HP | 15 HP |
| Bowl Speed | 7,500 RPM | 6,400 RPM | 6,700 RPM |
| Sludge Space | 0.325 Gal | 1.3 Gal | 2.0 Gal |
| Technical Specifications | |
| Capacity | 15 GPM on Biodiesel Glycerin |
| Motor Power | 5 HP |
| Voltages | 230 / 460 3-Phase |
| Size | 4' x 5' |
| Weight | 2,000 Lbs |
| Options | Teflon Coated Covers |
| Technical Specifications | |
| Capacity | 25 GPM on Biodiesel Glycerin |
| Motor Power | 7.5 HP |
| Voltages | 230 / 460 3-Phase |
| Size | 4' x 6' |
| Weight | 2,500 Lbs |
| Options | Teflon Coated Covers |
| Technical Specifications | |
| Capacity | 50 GPM on Biodiesel Wash Water |
| Motor Power | 15 HP |
| Voltages | 230 / 460 3-Phase |
| Size | 5' x 5' |
| Weight | 2,800 Lbs |
| Options | VITON O-Rings |