Mineral Filter Aids for Cleaner Fuels

In Honor of the Successful National Biodiesel Conference & Expo


Ethanol Bioenergy Facility

This year, the National Biodiesel Conference & Expo was held virtually from January 18th through the 21st. While unable to meet in person, the conference was able to bring together industry professionals to share expertise, best practices, and new ideas. In honor of this successful event, today, we are exploring the use of mineral filter aids for cleaner fuels.

Mineral Filter Aids for Cleaner Fuels

Why Biodiesel Filtration Is Important

Phosphorous and soaps are two main impurities targeted for removal. These impurities are created during the process of neutralizing free fatty acids.

When biodiesel is made, soap is produced as a by-product when free fatty acids in the oils mix with water and catalyst. Generally, the higher the free fatty acid level, the higher the soap content. It is considered a contaminant and congeals in the filter fibers, reduces throughput, causes clogs, and increases the time it takes for producing. Also, when soap burns, it leaves behind an ash residue in your engine.

Phosphorus can be found in plant oils when a phosphorus-containing fertilizer was used. Phosphorus also needs to be filtered because the phospholipid compounds can greatly impair the effectiveness of emission control systems. The effects are cumulative, so over time, even trace levels can cause severe damage.

Using a filter media is important because it prevents the cloths used in a filter press from being blinded, which happens when too many particles are collected and oil can no longer pass through. Filter media can also be added to the bulk of the oil being processed before it passes through the filter press. This increases the time it takes for the liquid to be filtered.

Diatomaceous Earth Filter Aids for Cleaner Fuels

To see why diatomaceous earth is a great filtration media and filter aid, you’d have to view it under a microscope. Diatoms have a wide variety of shapes and a honeycomb-like structure. The pores within and between the cell walls are so small, they trap bacteria, clay particles, some viruses, and other suspended solids from liquids, leaving liquids cleaner and with drastically reduced solids and contaminant levels. Benefits include:

  • High Porosity. The pores within and between the cell walls are so small, they trap bacteria, clay particles, some viruses, and other suspended solids from liquids, leaving liquids cleaner and with drastically reduced solids and contaminant levels.
  • High Flow Rate. Diatomaceous earth filter cakes extend the flow rate of the material being filtered and prevents clogging.
  • Longer Filter Cycles. The high solids holding capacity of diatomaceous earth allows for much longer filter cycles (allowing more solids to be removed) than what would be possible with other filtration methods.

Perlite Filter Aids for Cleaner Fuels

Perlite is an amorphous mineral consisting of fused sodium potassium aluminum silicate. In its natural state, it’s a dense, glassy rock formed by volcanic rock. When crushed and organic acids at both low and high and treated under proper conditions, perlite pops like popcorn, expanding up to 20 times its original volume. There are many reasons it is an ideal candidate for filtering oils:

  • Easy Application: Experience in a variety of applications has shown users can easily switch their current filtration media to a perlite filter aid economically and without sacrificing performance. It can be used with either pressure or vacuum filtration equipment.
  • Inert State: Perlite is naturally inert, so no tastes, colors, or odors are transferred to the filtered product. This is especially important for food applications.
  • Insoluble: Perlite filters are virtually insoluble in mineral and organic acids at all temperatures. Solubility in strong alkaline solutions varies, depending on temperature and contact time.
  • Lower Weight, Same Volume: Perlite filter aids can weigh as much as 50% less than the other types of filter media. This makes it easier and safer to use.
  • Impressive Density. Perlite filter aid grades provide the user with a density advantage from 20 to 50% over other types of filter aids.
  • Anti-Caking: Perlite filter aids are also revered for the end of the filtration process; the filter cakes remain porous and do not compact.
  • Cost Savings: When compared to other filtration media, like Diatomaceous Earth, perlite offers comparable savings in filter aid usage, especially on rotary vacuum precoat filters.

Pacific Biodiesel’s Impactful Solution Using Mineral Filter Aids for Cleaner Fuels

Pacific Biodiesel is the nation’s longest operating biodiesel producer and established the first retail biodiesel pump in America. The company is working toward making Hawaii more petroleum-free. Pacific Biodiesel recently made upgrades to its recycling operations at its 5.5 MMgy biodiesel production facility. The company recently improved the pretreatment equipment with a new set of filter press plates with diatomaceous earth that can preprocess cooking oil. One of the most abundant contaminants is polyethylene that is rendered in tallow and animal fats found in carcasses from ear tags or trays and melted plastics from recycled food waste. Using the diatomaceous earth and filter press plates, Pacific Biodiesel has been able to pull out the material. This is a great accomplishment because still to this day, many production plants say there is nothing they can do to pull this material out. After the oil is filtered through and the DE captures the poly materials, a dry filter cake is left behind. Rather than throwing it away, Pacific biodiesel is looking into whether the filter cakes can be repurposed after use and converted to a soil amendment or fertilizer.

Dicalite Management Group Knows All about Mineral Filter Aids for Cleaner Fuels

Dicalite Management Group’s superior mineral filter aids are light in weight, chemically inert, and form high porosity filter cakes to maintain a free flow of the liquid. The structure of the particles must be such that they will not pack too closely. This not only permits high initial liquid flow but also provides pore spaces to trap and contain the filterable solids and leave a high percentage of channels remaining open for flow. Particle size distribution must be tailored to permit precoating on coarse wire and yet give the desired flow rate and clarity. Diatomaceous earth, perlite, and cellulose are widely used materials that meet these criteria.

Our multi-offering of diatomaceous earth, perlite, and vermiculite equip us with the knowledge and products to support your filtration needs. Our customer service representatives located at our plants are standing by, and our technical experts are anticipating your call. Call us today at 866-728-3303 for your free sample and to see for yourself what makes Dicalite Management Group a customer-first industrial minerals company.

If you’d like to learn more about using minerals for filtration, download our free e-book A World of Filtration Experience today.

Join Our Mailing List

Our blog offers insight and information about new and exciting uses for perlite, diatomaceous earth, and vermiculite deriving from years of research and application. From passive fire resistance to mineral depth filtration, by subscribing to our mailing list, you will receive the latest information surrounding the Dicalite, Dicaperl, and Specialty Vermiculite brands and products.

Join Our Mailing List
Dicalite Introduces Harvest Hero, a New Gardening Product Line Focused on Growing Media & Soil AmendmentsShop Today