The plate filter press, tips and tricks

[Russell Lampron]

For most, filtering syrup is the messiest and most frustrating task in the sugar house. This thread is intended to be a guide for the operation of the plate filter press. If you have a good procedure for operating a press share it here. If you need help figuring out how to operate your press or if you want to know how to operate it more efficiently ask your questions here.

My experience started with a Wes Fab 7" hand pump press. It didn't take long for me to realize that I needed a mechanical pump of some sort to save my arm. I swapped out the hand pump for an air operated diaphragm (AOD) pump and the messes began. The hand pump press wasn't designed to handle the pressure that the AOD pump produces and it was squirting hot syrup from between the plates all over the place, including the ceiling of the sugar house. I figured out that I had to run the pump at the lowest speed possible to keep the pressure down. This allowed me to get a reasonable amount of syrup through it before I had to change papers. I produced about 15 gallons per boil and could get that filtered with ease.

Fast forward to 2022. This season I helped a friend with 12000 plus taps make syrup and was shocked by the way that he operated his 10" press. He waited until his draw off container had about 30 gallons of syrup in it and then mixed in 7 grain scoops of filter aid (DE). He then started the press which also has an AOD pump on it. He set it at about half throttle and opened the bypass to control the pressure. He was filling a 55 gallon barrel and before it was full the pressure got too high and the flow too low to continue on. At that time I asked if I could try something before he changed the papers. I closed the bypass and started the pump so that it just barely pumped. To our amazement we got another 30 gallons through the press before we had to change the papers. Most importantly we were able to get the level in the draw off container down low enough to be able to change papers without overflowing it. From then on operating the press was my job.

I'll explain what I learned in another post as I've found that post that are to long don't get read (TLDR).

[ecp]

Continues filtering is much less running around for sure. I see a lot of posts about filter press issues and read most of them. There are a lot of different ways to operate them and for some reason no 2 presses are the same which I find odd. Last night (first time ever) my 2 presses kept clogging with niter flakes in the hollow plate holes. Has anyone else experienced that?

[Russell Lampron]

The next thing to know about is DE. How much to use to charge the press and how much to put in per gallon of syrup. There is no cut and dried formula for this. As with most of us I read posts on this forum and did it by trial and error, mostly error at first. When I found something that worked I stuck with it.

When it comes to charging the press this is what worked for me. For a 7" three plate press I used 2 cups of DE, for a 7" seven plate press I used 3 cups and for a six plate 10" press I used 9 cups. To charge the press mix the amount of DE that you're going to use with enough hot syrup to completely fill the press and a quart or more extra. Start the press and pump the mixture through. For an AOD pump run it fast enough to build about 10 psi, this distributes the DE evenly and forms a cake that will stick to the papers. For those of you with gear pump presses charge it with the bypass closed. When the press is full keep pumping the mixture through until all of the DE that was in the syrup is in the press. Now pour the remaining syrup into the syrup to be filtered. Start pumping your syrup back into the syrup to be filtered until it is clear. Your press is now charged and you can start filtering.

I'll cover batch filtering and continuous filtering in my next post.

[cropseyvillemark]

Thanks for starting this thread. Please keep the tips and tricks coming!

[Russell Lampron]

Now that the press is charged it's time to discuss the filtering process. There are two ways to filter syrup, batch filtering and continuous filtering.

The first, batch filtering is done by filtering all of your syrup at one time. Before you filter your batch you need to know how DE to use and if that amount is more than your press can hold. In my research I've found that recommended DE amounts vary from 1/5 cup to 1/2 cup per gallon of syrup with more being used for dirtier and late season syrup.

To find out how much DE your press will hold measure the inside opening of a frame with this formula, length x width x depth equals cubic inches, LxWxD = CI. Then multiply that number by the number of frames that your press has and that will give you the capacity in cubic inches. Now convert the cubic to cups. One cup equals 14.428ci. A press frame that measures 6x6x1 for example holds 36ci. If that press has 4 frames the capacity will be 144ci. Now divide the cubic inches by 14.438 to get the number of cups that the press will hold, 144÷14.438=9.937 cups. Now subtract the number of cups of DE that you charged the press with 10-2=8, to find how many more cups of DE that you can use in your batch of syrup. If you use a 1/4 cup per gallon one cup of DE will filter 4 gallons of syrup. Multiply that by the number of cups 4x8=32 that you can add to the batch and you should be able to filter 32 gallons of syrup before the press is full.

Clear as mud right! Next I'll cover continuous filtering.

[ecp]

Now that the press is charged it's time to discuss the filtering process. There are two ways to filter syrup, batch filtering and continuous filtering.

The first, batch filtering is done by filtering all of your syrup at one time. Before you filter your batch you need to know how DE to use and if that amount is more than your press can hold. In my research I've found that recommended DE amounts vary from 1/5 cup to 1/2 cup per gallon of syrup with more being used for dirtier and late season syrup.

To find out how much DE your press will hold measure the inside opening of a frame with this formula, length x width x depth equals cubic inches, LxWxD = CI. Then multiply that number by the number of frames that your press has and that will give you the capacity in cubic inches. Now convert the cubic to cups. One cup equals 14.428ci. A press frame that measures 6x6x1 for example holds 36ci. If that press has 4 frames the capacity will be 144ci. Now divide the cubic inches by 14.438 to get the number of cups that the press will hold, 144÷14.438=9.937 cups. Now subtract the number of cups of DE that you charged the press with 10-2=8, to find how many more cups of DE that you can use in your batch of syrup. If you use a 1/4 cup per gallon one cup of DE will filter 4 gallons of syrup. Multiply that by the number of cups 4x8=32 that you can add to the batch and you should be able to filter 32 gallons of syrup before the press is full.

Clear as mud right! Next I'll cover continuous filtering.

But how would you be able to hit the nominal number if sugar sand fills the press as well?

[Russell Lampron]

But how would you be able to hit the nominal number if sugar sand fills the press as well?

The reality of it is that the volume of the nitre isn't something that we can measure before we filter. You can use a little less DE to compensate for it because most of the time you can use less and not have a problem.

[ronintank]

I have the daryl sheets press its a 5 inch and i usually run about 8-9 gallons at a time through it per batch.
for my press with all the plates in it. i charge the heated to 200 deg. syrup with 3 cups of DE i use a wisk to mix the de into the syrup when mixed i place the suction hose and the jar filling hose into the syrup kettle and start hand pumping.
Recycling the charged syrup through the press and back into the kettle. this heats the press and fills the chambers in the press with the proper de bed for complete filtering. I would say i hand pump if for about 3-5 min. then start filling jars.
In my mind you need enough de to create the proper filter bed for how many plates you use for your size press. it is not based on how many gallons you run through it. on my sheets press i think the void plates are 3/4" thick and the perfect bed is 1/4" de per side with a 1/4" gap in the middle, this gap will allow for a batch with lots of niter. Before i filter i let the finished syrup sit for a couple days to let the niter settle out so the syrup i filter has a low niter amount in it.

[Amber Gold]

Russ, that's a great idea when the press plugs up at the end of a night. In the past, I've broken down the entire press to get the last of the syrup through. It makes way more sense to just clean out the last plate and get that little bit of capacity back that you need. Thanks.

[Russell Lampron]

I've just reread what I covered above and realized that I haven't covered one of the most important things about successful filtering and that is temperature. As with DE usage the information out there isn't always true. Most recommendations are correct when they say that the syrup should be at 200* or higher. I did find a video by Smoky Lake that said not to go over 192* to filter because the syrup will precipitate more nitre. While that statement is true for heating syrup it's not true for cooling syrup. The ultimate goal is to have the syrup coming out of the press hot enough to sterilize the container that you're filling. As we all should know that temperature should be 180* or higher.

If you've seen that video disregard the temperature recommendation and heat your syrup to 200* or higher. The hotter the syrup is the easier it will it will be to filter.

[Russell Lampron]

Now on to continuous filtering. I found virtually no information on this other than a mention of it being a type of filtering. With continuous filtering you're going to add the DE to the syrup while you're filtering.

To do this you're going to need to know how many gallons your draw off container will hold and set a target level to add the DE. For example when you reach your target level add the amount of DE for that quantity of syrup and begin filtering. Keep an eye on the syrup you're filtering and add more DE when you reach the target level again or when you can't see much DE in the syrup to being filtered. You can guesstimate here as to the number of gallons that has come into your draw off container since you started the press and add the appropriate amount of DE.

In some cases you're going to empty your draw off container waiting for syrup to come. In that situation shut off the press and wait until you reach the target level again, add DE and restart the press.

It's okay to shut off the press for short periods of time and start again without doing anything to keep the press hot. If that period is going to be long enough for the syrup coming out of the press to be below 180* pump the syrup back into the draw off container until it's hot enough to continue filling containers. The pressure will be a little higher when you start out but will come back down as the press comes up to temperature.

Someone on this forum said that he let his press sit until the next day and was able to start it again and filter on. I tried it myself to see if it was possible or if it was bs. It was very sluggish and the pressure was real high at first but it did work and I was able to get another day's boil through it without changing papers. As a disclaimer here, I don't recommend that you run your press this way! I only did it to see if it was possible.

[Thompson's Tree Farm]

Russ,
We often use the press a second day. If the plates are no where near full of DE we flush the press with hot water off the pre heater and dump it back into the evaporator. Next morning we do the same thing to pre heat the press. Works fine. We always flush the press with hot water and put that water back into the evaporator before we break it down.

[Russell Lampron]

Russ,
We often use the press a second day. If the plates are no where near full of DE we flush the press with hot water off the pre heater and dump it back into the evaporator. Next morning we do the same thing to pre heat the press. Works fine. We always flush the press with hot water and put that water back into the evaporator before we break it down.

I always flush the press with hot water too but didn't the day that I tried my experiment. The sweet that I flushed out went into my draw off pan and was mixed in with the new syrup the next time that I boiled.