Lenticular Filter Sizing Guide for Beer

Last updated: 6/2021

Applies to: Brewers looking to size a lenticular housing (based on batch size), and choose filter media (based on flow rate needed).

FACTORS TO CONSIDER

Selecting the correct size lenticular filter for your brewing operation depends on three primary factors:

1. How much beer you need to filter (Batch Size) 
2. How much time you want to spend filtering/what your throughput is (Flow Rate) 
3. Do you anticipate batch size or throughput increasing over the next 3-5 years?

Below, we’ll consider how batch size and flow rate can help dictate the appropriate lenticular filter size, and how you can build a system that leaves room for production increases.

BATCH SIZE

Broadly speaking, lenticular filtration is appropriate for batch sizes up to about 140 bbl. The right filter for your production will not be grossly over-sized for smaller batches or under-sized for larger ones. The size of lenticular housings are classified by:

• diameter (12 or 16 inches)
• height in terms of modules (1,2,3 or 4)

The larger diameter and larger height modules are the most flexible: 16” housings can use both 12” and 16” media, and taller housings can use any number of modules by simply changing out the center post. For example: If batch sizes are projected to start small but you’d like to leave room for growth in production, you may consider a 16” 4-high housing for the most flexibility. We find it is best to operate as though you have more beer to filter, and that it is less filterable than you assume. It is better to have additional filtration capacity and not need it, than vice-versa.

See the table below to correlate lenticular housing size with batch size. The recommendations are based on performing a polishing filtration on a well-settled ale without stopping midway to regenerate. 

*Fine-tune sizing based on desired throughput, filter grade selection, and filterability of your beer.

**For batch sizes larger than 140 bbl, we recommend a centrifuge or pressure leaf filter to pre-clarify your beer before your final polishing step.

FLOW RATE

Flow rate refers to the rate at which a system can filter product. It is primarily gauged by the grade of filter media selected, and its diameter. Coarser media predictably yields higher flow rates and is balanced against tighter media’s increased dirt holding capacity. As with all filtrations, going too tight, too soon will yield lower throughputs and possible loss of mouthfeel, weight and color of the beer due to the increasing adsorption capability of tighter grades.

A system’s throughput is also influenced by many additional variables so it is important to take consider how they may affect the estimated flow rate of your setup. Again, when in doubt it is best to assume your beer is  less filterable than you think it is:

• Product turbidity & filterability (how cloudy the product is and how easy it is to remove the source of the cloudiness)
• Transfer technology (pump vs CO₂ pressure, head and flow rate of pump)
• Use of fining agents
• Pre-clarification (e.g. via pressure leaf or centrifuge)

The following table shows average flow rates for different media grades and sizes and should be considered a rough guideline. Flow rates are shown in barrels per hour  per module, for a well settled ale when starting filtration at a 5-7psi pressure drop. For a lagered product, flow rates can increase.

*1 US bbl. = 31 gallons **For carbon media to be as efficient as possible, we recommend a beer be brightly polished (K250 and tighter), so that carbon isn’t prematurely blinded with suspended solids. This practice ensures the highest total throughputs for carbon embedded medias and ensures the lowest cost per surface area spend.

Learn More

For more information on lenticular filters, usage, sizing and media, download our Lenticular Operating Instructions and watch our YouTube demonstration below.