Filter Trolley Q&A

Questions and Answers about our filter trolleys.

Q: Why do I need to winterize and dewax?

A: Some extracts have contaminants such as lipids, fats and waxes.  These contaminants cause foul smell and taste so must be removed.  By removing these fats and waxes you also improve shelf life and stability of your final products, reducing problems like discoloration and oxidation in distillate.  Also, since some crude oils may be 50% wax, by removing these earlier in the process it may reduce the amount of extracts to process in half.  You would thus save by needing smaller machines in the molecular distillation step of the process.  Wiped film and similar systems are also very sensitive to lipids and waxes, and may be damaged by the accumulation of these in the system.  Cleanup of these machines is also more difficult with crude oils that have not been winterized since they turn into carbon residues.  Filtration after the winterization process is the fastest and easiest way to remove lipids and waxes from your crude.

Q: How big is your filter trolley?

A: 800mm Filter Trolley is:
1.73x bigger than an Infinity MC8
1.78x bigger than 630mm Trolley
4.68x bigger than 400mm Trolley
1.73x bigger than DrainDroyd
190x bigger than 358ml Buchner
32x bigger than 800ml Buchner
1.73x bigger than 24" BelArt
29.9x bigger than a Hochstrom

 

Q: How fast does your 800mm trolley filter?

A: Although the pump on the trolley can pump 26 GPM, filtration rate will depend on filter surface area, porosity of paper/cloth used, filter aid used, solvent used, rate of solvent dissolution (ie 10:1), liquid temperature, viscosity, percentage of solids in suspension, suspended particle distribution, etc... The paper used will be the determining factor in your filtration rate. See our tables to determine rapidity when buying our filter paper.

 

Q: How fast does the 800mm trolley filter?

A: If using 1.5-micron paper, a maximum of 3.93 gallons per minute.
If using 45-micron paper, a maximum of 91.8 gallons per minute.
Vacuum assist increases speed.  The pump has a limit of 26 GPM.
Based on rapidity of our filter papers, being 60 mls/min on 901 Grade 1.5 microns and 1400 mls/min on 1278 Grade 45-micron Ahlstrom papers you can expect the above theoretical max flow rates. Those rates are on laboratory-controlled conditions at a set head and water temperature using distilled water. The bottleneck is the paper, not the system. Also, as the paper swells, filtration slows. As the paper clogs, filtration slows.

 

Q: What temperature does the pump operate at, as my AODD pump seizes at 0F.

A: Our standard pumps are rated to 0C. Our FDA pumps are rated to -20C, and offer pumps rated to -40C/F. All can be used in colder conditions, but it will lower your diaphragm service life. It is a trade-off you must choose. Fortunately, servicing these pumps is easy and inexpensive.

 

Q: Have you tested your filter trolley at -86C? It says PP temp range at -15c I believe.

A: “A key factor in the molecules’ ability to slip and slide is temperature. Specifically, there is something called the “glass transition temperature” (Tg), which is the point below which an amorphous solid (such as glass, polymers, tire rubber, or cotton candy) goes from being ductile to brittle. For most common materials, says Rutledge, this temperature is so high or so low that it is not easily observed – the Tg of window glass is 564 degrees C, and that of tire rubber is -72 degrees C.

But many plastics exhibit their transition at everyday temperatures and can be “frozen” into brittleness. One example: polypropylene, an inexpensive material often used in containers, toys, outdoor furniture, and recycling bins has a Tg of between -20 and 0 degrees C, so it can easily lose its molecular mobility and become shatter-prone on a winter day.”
https://engineering.mit.edu/engage/ask-an-engineer/why-do-plastics-get-brittle-when-they-get-cold/
We do not condone the use of our equipment outside of material tolerances. That being said, it is improbable that the 20mm thick PP will crack because of temperature itself. Fractures would be the product of an impact (mechanical shock) while at glass transition temperature and or subjecting the machines to quick shifts in temperature (thermal shock) say by pouring a hot solution on a -70C machine. Our trolleys filter cold winterized fluids without fractures.
Users who chill their equipment usually use steel units which have an efficient thermal transfer and will warm your solution and potentially drop lipids from suspension. We make our machines of plastics with a high R value that does not transfer temperature well so will not warm your solution.
You do not have to chill your equipment to operate successfully. If you do, be careful as our warranty would not cover this issue.
Note that stainless steel is also subject to Tg.

 

Q: Why is no solution coming out of my pump?  I started it a few minutes ago and nothing happens!

A: Most likely you simply have to wait.  It takes time for solution to percolate down and work its way through the pipes and pump.  It may be 3-5 minutes before the first filtrate makes it out. Check out our Blog for more tips.

 

Q: Are they C1D1 compliant?

A: Yes.  There are no controls or electrical pumps, so this equipment cannot generate any sparks, so it is safe to use in a C1D2 environment.  The pump runs off of compressed air, which you must supply.

 

Q: What consumables do you need for this machine?

A: These machines can use filter paper of any grade or porosity, filter cloth and filter aides of various types and grades.

 

Q:  Where do we get this paper and cloth?

A: We sell paper and cloth.  You can also buy the paper off of Amazon or lab paper manufacturers.

 

Q: What exactly is the cloth used for?

A: The primary function of the cloth is to create a uniformly porous surface for your filter paper to sit on.  The filter grate for obvious reasons has holes to filter through and thus reduces the total filter surface area.  If you use paper alone and do not place the cloth beneath the paper, in effect you may only have half or less of the filter surface area!

When using paper, we always recommend using the filter cloth.  It helps prevent tearing the paper from excessive vacuum, and it adds uniformity to the filter grate perforations.  Basically, the cloth helps to filter faster and prevents the little round patches you are used to seeing in your funnel; the cloth distributes vacuum evenly throughout the paper.

The cloth can also be used on its own, covered with a filter aid for a rough pass filtration.  When you move on to polishing pass, you would use a smaller micron filter paper.  The cloth should last several months with proper care.

 

Q: What’s the smallest micron paper you can use?

A: You can use ANY porosity filter paper. Here is what we sell, but if you need a special grade, we can make it for you.

 

Q: Why is paper so expensive?

A: Lets do the math.  Comparing to the popular 5.5" Hochstrom filter, it takes 29 sheets to equal 1 sheet of the 800mm trolley.  Stage 1 (20 micron) Hochstrom paper costs $0.225 per sheet.  Stage 2 (8 micron) costs $0.225.  Stage 3 (1 micron) costs $1.00 per sheet.  Multiply by 29 and it works out something like this per sheet when you buy in bulk:

Stage 1 (Competitor) $6.65 / Us $3.05
Stage 2 (Competitor) $6.65 / Us $3.80
Stage 3 (Competitor) $29.00 / Us $7.50

 

Q: Are they ASME certified?

A:  Filtration equipment does not get ASME certified, so there is no filter trolley that can get ASME certified.  We follow all guidelines with the piping, hydraulics, plates, etc... but the unit itself cannot be certified.  For example, we have equipment in many bottling, brewery, and liquor applications where all equipment must be FDA certified.  Each component on the filter follows FDA guidelines, but the filter itself cannot be FDA certified despite all components following the guidelines. Our pumps are CE certified, which satisfies most Fire Marshall requirements.

 

Q: Are they food grade?

A:  The materials we use to build these machines are FDA Certified, we can provide written proof upon request. The PP pumps that come standard with the unit are not, but you can upgrade to an FDA pump.

 

Q: Are they FDA CGMP Compliant?

A: Though our basic trolley model is made with PP that is food grade, the PP used in the AODD pump is not. We offer an FDA AODD pump upgrade to comply with FDA Current Good Manufacturing Practices.

 

Q: Are they insulated or jacketed?

A: Yes, they are insulated. Unlike a metal option, this thick plastic has a high R value and has little thermal transfer. Your solution will stay cold far longer than a metal machine.

 

Q: Is there an interior lining (PTFE or other) to protect against solvent leaching?

A: A Google search took me to a quick reference chart of chemical compatibility for Polypropylene. I’m no chemist but basically the articles states that the PP was submerged for 48 hours and the following chemicals show excellent compatibility to PP which I understand means no reaction. Ethanol, Isopropyl, Methanol, Hydrochloric, Nitric. I’d stay away from Pentane. Hexane and Heptane show good and fair compatibility.  A liner is unnecessary.  Reference: https://www.calpaclab.com/polypropylene-chemical-compatibility-chart/  

 

Q: What about terpene compatibility (ie. crude, pre-distillation)? Can you offer a liner/coating etc (GMP)?

A: There are no compatibility issues with Terpenes or crude. It’s exactly what we are offering this equipment for. We tried d-Limonene which is a good measure as per strong Terpene solvents and there are no issues.  Polypropylene and compatibility with d-Limonene, browsing online many manufacturers including US Plastics do not recommend the use of the two together.  However, what is not recommended is the prolonged use, as in submersion, over time of pure heated (+70C) Limonene.  The <1% contained in your solution does not pose a risk.  Neither does cleaning your equipment with Limonene.

 

Q: Can you use solvents on this machine?

A: Ethanol, Iso, Methanol, etc... are safe to use.  So is pure Hydrochloric acid and many other acids and solvents.

 

Q: Can you use silica on this machine?

A: Silica as in DE (diatomaceous earth) and Silica Gel 60 (though expensive and not recommended for this application) can be used on these filters as well as Perlite, Alumina and any other filter aide.

 

Q: How about carbon or clay?

A: Yes, this is a filter so you can filter out any solids from your solution.  To filter out carbon, we recommend a filter aid and the right porosity filter paper.  Clay is problematic as it tends to blind the paper, so we suggest lots of filter aide as a pre-coat, or added to the solution before filtration.

 

Q: How difficult is this machine to clean?  I heard cleaning PP was next to impossible and I am afraid if it gets contaminated with Miclo I’d have to throw this machine away!!!

A: Our machines are safe to clean with pure or diluted Nitric, Hydrocloric, and Sulfuric acids as well as Caustic Soda.  We recommend using a soft cloth or sponge with Limonene followed by a solvent wash with a spray bottle.  Dry solvent with a paper towel.  You can’t use pure nitric on a steel funnel!

 

Q: Does this have a way to get to temp (-50) to dewax? Or just filtration only?

A: Filtration only.  It does not chill.  DO NOT throw dry ice in this machine as you will void your warranty.

 

Q: What is dewaxing anyways?

A: Winterization is when you freeze the fats, lipids and waxes usually overnight and then filter them out (Dewaxing). Therefore, dewaxing commonly refers to the removal of lipids, fats, and plant waxes from oils and/or botanical extracts.

 

Q: What material are these machines made of?

A: Quality German Polypropylene (made by Bayer) thermo-welded plastics.

 

Q: Where are these machines made?

A: Arezzo, Italy by skilled Italian craftsmen in a rural village in Italy.

 

Q: How loud is the pump on the trolleys?

A: 70 dB, yes it is loud.  You can get a muffler to help with the noise.

 

Q: How much air does the pump consume?

A: A maximum of 17.9 CFM at 100 PSI. Normal operation is 25-50 PSI.

 

Q: What size air compressor do you recommend?

A: Consult an expert based on the pump curve for this machine, but the quick answer is a 5Hp 80 Gallon compressor. You can purchase any one of these.

 

Competition Analysis

Q: How does this machine compare to the competition?

A: It’s on a league of its own. Seriously! Our machine is usually bigger and cheaper than competitors, and has many features that make it easy and convenient to use. We offer knowledgeable support and don't sell hype.

 

Q: How does your trolley compare to the Infinity Manufacturing MC8 Filter Table System?

A: The MC8 is similar in size to a 630mm trolley, actually slightly smaller. At $7,750 for a non-insulated model, our insulated trolleys are about $100 cheaper. MC8 has 3 funnel units, but cost triple the price of a trolley. The MC8 does not include required pumps; the trolleys include pumps and are ready to ship. Our trolleys have proven their reliability for four years now and are used by companies throughout the world, both large and small.

 

Q: How is the trolley better than a DrainDroyd?

A: The DrainDroyd is a quality stainless steel filter.  Unfortunately, it has the following shortcomings:

• It is very expensive; I was quoted upwards of $17,000 delivered.

• It doesn’t include a vacuum pump needed to operate. Sold Separately.

• It uses a vacuum pump.

• The mechanism used to hold down the filter paper is not efficient. The filter paper leaks. Improvements have been made to this design, however.

• The hopper is not made to be filled with a solution, you must slowly add as you filter.

• Filling the hopper makes the machine top heavy, and it becomes dangerous as it easily tops over.

• It is made of steel that will quickly warm your solution.

• It is not insulated.

• You cannot use acids to remove Miclobutanil from this machine.

 

Q: How is a trolley better than a Hochstrom filter from Summit?

A: The Hochstrom filter is a small 5.5" ID filtering funnel, limited to small-scale laboratory filtration.  Many pieces, including pumps, and glassware are required to make that filter operate.  A set of 4 Hochtrom filters with accessories costs upwards of $12,000 as per the manufacturer’s website.  Also, a $17,500 vacuum pump is recommended for these systems.  The SC Filtration 800mm trolley in contrast includes all accessories needed to operate, and you would need 29 of these small Hochstrom filters to match our filter area.

 

Q: Why are trolleys better than a Bel-Art which is far cheaper?

A: Bel-Art funnels are simple and inexpensive filters.  Unfortunately, they have the following shortcomings:

• They easily crack under extreme cold temperatures as they are made of thin PE.

• The bottom filter grate warps over time with cold temperatures.

• The hopper loading capacity is small as the unit is not very tall.

• It doesn’t come with a pump.

• The filter paper flares at the edges, and it tends to leak. It is not meant to be fully submerged.

• The hopper is not made to be filled with a solution, you must slowly add as you filter. This makes it more labor intensive than a trolley.

 

Q: Why is a trolley better than a Chinese Nutsche Vacuum Filter?

A: A 30 Liter, 400mm Nutsche system seems to retail from $1500-2000 and has the same capacity of our 400mm $6,950 unit.  Unfortunately, after shipping and the necessary pump, you are likely to spend $6-7,000 for one.  In reality, the capacity and throughput are about the same as our unit.  Though some Chinese companies offer high-quality products, many have quality issues with inferior glass and metals that rust.  If your glass breaks, how do you replace it?  Will your manufacturer honor a warranty?  Our trolley will not break, are made from top quality European components and we offer US service, support, and replacement parts.

 

Q: How is a trolley better than a lenticular filter?

A: Lenticular filters are pressurized filters where you must pump your solution into a closed canister.  They excel in many industries and have specific applications where the filters inside capture particles inside the filter membrane, and not just on the filter surface area like a paper does.  Removal of waxes is not recommended for this filter as the surface quickly clogs and and little waxes are actually collected inside the membranes.  A lenticular filter is also very expensive, costing $5,000 for the filter Housing alone with no pumps.  The single use cartridges are also expensive, costing as much as $1,000.00 for a cartridge change. Use lenticular for cold centrifuge extracts, and a trolley for CO2 or BHO crude, or if your budget or operation is smaller. You can purchaser lenticular systems here.

Further Questions

Q: Let’s say for a standard setup: Whatman #1 equivalent paper, BHO extract dissolved in ethanol at -20C, no filter aid, and your biggest surface area trolley. How long until the filter cloth clogs up on first pass?  50% potency. An OG with heavy waxes. I’m kind of struck that SC doesn’t just answer the question for any set of ‘normal’ working conditions...whether it’s room temp filtration followed by cold or straight to cold, use of a filter aid, etc. Is it too much to have an SOP? My fear with all filtration solutions is that the filter paper clogs and needs to be replaced within 30 seconds of operation.

A: So let’s go over this in layman’s terms. What % of wax is in your crude? Not all BHO is the same and % of wax differs by strain or batch and method. The greater the wax the slower the filtration rate. Is it going into the filter at -20? Or are you winterizing at that temperature, then letting it warm up a bit before filtration? The colder the solution the slower it filters. What solvent? I can imagine 80% ethanol at -40C that is more a slurpy than a liquid. See how all that makes this calculation difficult? What dissolution rate? I have customers doing 40:1 which will obviously filter faster. 10:1 is slower. What paper porosity? Obviously 1 micron will be slow if used as a first pass. But if you do a rough pass at 45 microns then 5 then 1.5 it’s totally different speeds. This is where particle distribution becomes important. You remove the chunky stuff first. Why no filter aid? This will solve the fast clog issue. In the end our machine will filter as fast as your conditions permit. We will help you develop an SOP that is effective and makes your life easier. Through shared knowledge we have learned, we will help you deal with slow filtration issues and increase longevity of the papers used.  Each lab processes different materials with different conditions on different equipment so there is no universal method. I know I didn’t answer your question, but I hope you get the point without me sounding like a smart ass. 😅

 

Q: I need to have a pump that’s UL Certified, also a filter press that’s is UL CERTIFIED can you help?  What about ASME?

A: Yes.  We can design to UL 508A if required.  ASME really has no jurisdiction over our design since we are not a system under high pressures or contain pressure vessels.  Neither of these certifications are required for our system.

 

Q: Do you have a storefront?

A: We do not. We manufacture our plastics in Germany and assemble the trolleys in Italy. Our warehouse is in Miami, FL.  If you are around Florence, Italy we would love to show you the factory floor. We have many retailers if you need to see a trolley in person, and we offer demos and rentals from time to time.

 

Q: Do you do demos?

A: No, view our YouTube channel instead.

 

Q:  How does a diaphragm pump work

A: Air drives a piston inside the pump that moves 2 diaphragms.  In each cycle the pump sucks with one diaphragm and pumps with the other.  This reverses the next cycle as now one diaphragm pumps and the other sucks. 

Here is a video for further explanation: https://youtu.be/SCo9My_dz_U

 

Q: What trade shows do you plan to exhibit in.

A: MJBIZCON in Vegas, some NCIA shows, CANNACON, IndoExpo, LIFT and possibly others from time to time. 

 

Q: Are you the only one who sells that size paper?

A: You can buy the paper online, order from a manufacturer, or buy off of Amazon and cut manually to size if need be.

 

Q: How often do you change your filter paper in a single run? If you are filtering 55 gallons in a single run.  Would I have to split up the run?

A: It depends. If using a small trolley, I would expect many paper swaps. If using the 800mm less so.  If using filter aid, even less paper swaps.  It depends how many gallons of wax you expect to remove from those 55 gallons.  If it’s Co2 crude at 50% wax, I would expect quite a few swaps.  The porosity or grade of paper used will also determine how many swaps. 

 

Q: When do I need to change my filter papers?

A: When you notice the filtration speed is too slow, probably at 10-20% of when the paper was new.  So if you started at 4 liters per minute and now the flow rate is under a liter, it will soon be time to change the paper before it totally clogs up.

 

Q: I have 20 gallons of solution on my trolley and my paper is now clogged.  There is no way this will filter out even if I leave it working overnight.
A: Looks like you overdid it. Live and learn. Grab a soft or silicone spatula and scrape the wax off the paper. This will get you filtering again. Change the paper ASAP. 

 

Q: This machine looks heavy. How much does it weigh?

A: The 400mm you can pick up, at 70 pounds.  The 800mm is about 200 pounds.  All are easily movable as they ride on included wheels. 

 

Q: Is the filter plate removable for cleaning?

A: You mean the filter grate?  The filter paper sits on top of the grate which yes is easily removed with the included keys. 

 

Q: What filter paper grade do you recommend?

A: 10 micron with a slight layer of filter aid.  Most customers filter at 45-10 micron once, winterize again, filter at 10-5 micron, winterize again, and filter again at 5-0.7 micron.  It depends how much wax needs to be removed and how knowledgeable you are with dewaxing and winterizing process.  

 

Q: How many times do you recommend we winterize and filter?
A: Once.  Three times for optimal results. 2 reasons people filter 3 times is because they use steel or glass filters that may melt waxes, or their papers leak on the edges and wax gets through. Your dilution rates or solvent of choice may be the problem. You may also not be winterizing cold enough or long enough.  Do lab tests to determine best conditions for your material.  You may also choose to filter 3 times to get better results.  One pass could yield removal of 98%+ of waxes.

 

Q: What is the typical SOP your customers do when winterizing and filtering?
A:

1. Find the perfect solvent:crude ratio for your material by conducting lab tests.

2. Freeze (winterize) your solvent/crude mixture overnight to as cold as possible, preferably in a -86C freezer.

3. Filter using 1278 grade filter paper covered with 1-2" of your favorite filter aid.  This removes 90-98% of waxes.  Wash your filter aid with cold ethanol before disposal to recover any remaining crude.  The ethanol (or solvent of choice) wash is important not only for recovery but for dilution, as waxes will drop out at different rates with different dilution rates.

4. Winterize your solvent mix once again.  Filter using 923 or 986 grade paper using no filter aid.  Recover 1-9% of the remaining wax.

5. Winterize your solvent again.  Filter using 909 or 901 grade paper using no filter aid.  Recover the last remaining portion of wax.

 

Q: What is a filter aid anyway?

A: Something to help prevent your filter paper from clogging prematurely.  I like DE (diatomaceous earth) found as Celite at your local brew supply place.  Also, Perlite and a host of other powders can retain solids before it gets to your paper. 

Please Google silicosis https://en.wikipedia.org/wiki/Silicosis
We strongly recommend the use of food grade or lab grade minerals and filter aids in your process to avoid the remote possibility of including crystalline silica to your products.

 

Q: Installation of the filter paper sucks!  It took me 10 minutes!  This doesn’t work for me.

A: Paper installation should be quick and easy.  Don’t be scared to crimp, fold, or shove your paper in place. It shouldn’t tear easily. Quickly wrestle it into the groove and secure it with the gasket.  The installation process is not a delicate one, don’t be afraid.  Folds or creases will not cause filtration problems. The paper need not lie flat on the grate to work great, it just needs to be properly sealed at the edges.

 

Q: What is the lid for?  Does the lid create negative pressure for filtration?

A: The lid is to prevent evaporation and does not create or modify pressure.

 

Q: What kind of warranty do you offer?

A: We guarantee the mechanical operation of this machine for 12 months from date of purchase.