Pre-coating the Filter Press

[SeanD]

The directions for my press say (and I've read here) to pre-coat or charge the filter press with 3 gallons of syrup or hot water and DE. Is that only if I'm filtering as I draw off?

If I'm batch filtering, do I still need to do that? Couldn't I just mix the DE I need into the batch and recirculate it until it is clear? I've seen videos where people batch filter that way.

[MISugarDaddy]

If you are batch filtering, do as you asked, mix the DE with 3 or so gallons and recirculate it until it is clear, then run the rest of the batch through your press. If your pressure starts to build, mix in a little more DE to the remaining syrup in the batch. We normally do 10 gallon batches. We start with about 3 gallons of syrup and 3 cups of DE to charge the press, then mix about 2 more cups with the rest of syrup to continue to build the cakes in your press. (Our press is a 7" press with 4 sets of plates.)
Gary

[SeanD]

Ok, thanks for that. Tomorrow I'll be filtering about 11-12 gallons. It's really cold out there. If I heat 3 gallons to prime the press, the rest will be cold when I add it to the pot/finisher and I'll have to wait for it to heat up. I'd read that once the press starts going not to stop it and restart it or it will pass DE. How do you introduce the rest of your unfiltered syrup to the 3 you used to charge the press?

[mainebackswoodssyrup]

Sean, how big is your pot? I would try and do it all in one batch, heating it all once or spreading it out in 2 batches. 3-4 cups of de for a half batch and 4-5 for a full batch. Adding cold syrup to the pot probably won’t work well. I’ve never had any luck trying to do it that anyway.

[JoeJ]

If you go back to the thread "How Much Diatomaceous to use" in the "Bottling and Filtering" forum, you can read my 3-18-2015 explanation of my take on proper charging and use of the filter press. When I bought my new 10" press after struggling with my 7" press for 10 years, I decide to figure out how to properly make it work. I carefully measured out and counted the number of cups of DE that i put into a bowl and wet it with water. I stacked up my hollow plates and packed DE into the stack of plates until they were all full. That was the total number of cups of DE that I needed to fill my press AND NOT PACK IT. The methods and formulas are is that post. From my observations and in my opinion, the vast majority of sugar makers do not run their filter presses correctly. You need to operate these machine methodically and scientifically. By scientifically, I mean you need to know exactly how much DE you are putting in your syrup. Not "I put in 2 scoops" or "I guess that I add 2 cups in 5 gallons". I know that my filter press holds 42 cups of DE when it is full. When I start my boiling, I put 42 cups of DE into a large 48 cup plastic container. I use 1/3 of my total DE, 14 cups to precharge my filter press in 5 gallons of syrup. After that, I add a carefully measured 2 1/2 cups in each 5 gallon batch until all of the DE in the plastic container is gone. At that point, I know my press is full and will continue filtering for quite some time. My press is usually full when I hit about 80 gallons and then the press will continue sometimes even up to 115 gallons. I have two measuring cups. One 8 cup large one to do the precharge 14 cups and a small 4 cup measuring cup to dispense the 2 1/2 cups in each 5 gal batch.
It does not matter if you have a 3 plate 7" press or a 7 plate 10" press, the same method is used. With a 7" press you would obviously have a container with a small number of total DE in it. It all comes down to how much DE it take to fill all of the hollow plates and how to properly add the DE to your syrup.

This method is also dependent on the type of DE that you use. If you are using the Dicalite in the Blue Bag, the numbers in my 3-18-16 post work. Dicalite is a finer DE than the black bag Celite. Celite is a courser DE and takes 1/3 less DE than the Dicalite. I found this out by using my formula working with Dicalite and then getting a bag of Celite and plugging my press way too soon. I called CDL and was told of the difference in the two grades of DE. I had to adjust my number of cups of Celite DE down 35% to fill the press.

If this is all too confusing, PM me and I will try to clarify any questions.

Joe

[MISugarDaddy]

Sean,
We heat all our syrup to be filtered on a kitchen stove before filtering it. We have a separate 10 gallon pot on a burner that we used to feed our filter press. We place approximately 3 gallons of syrup in the pot and add 3 cups of DE to it. We mix it thoroughly with a large whisk, then turn on the filter press. (We keep that syrup hot by lighting the burner under it during the entire filtering process.) We recirculate the syrup and DE back into this pot until the syrup runs clear. We then pour in more syrup off the stove into the pot and at the same time, start discharging the clean syrup into our bottler. If the batch is large enough to require it, we mix 2 more cups of DE into the pot as it is being pumped through the press to increase the cake size in the filter press. The largest batch we can bottle at one time is 12 gallons due to the size of our bottler.

After the last of the syrup is drawn out of the pot, we add about 3 gallons of boiling water to empty pot and pump that through the press and collect it in a separate food grade pail. This removes any syrup remaining in the press. We add this watered down syrup to the evaporator the next time we boil. This idea was unfortunately not mine, but rather a good friend/fellow trader. It gets more syrup out of the press than just draining the press when you are finished.

Good luck with your filtering endeavor. Once you figure out a good technique, you will really love having a filter press.
Gary

[SeanD]

Ok, this is all great info. I had originally planned this out for filtering at the end of a boil. Those nights, I'll have 3 gallons of already hot syrup in a bucket that I can use to charge the press. The rest of the batch will be in a 16 gallon pot on a turkey fryer heating up for when the press is ready. From there I can go to a blue barrel or my bottler.

I hadn't thought about doing this on days when I'm not boiling. It sounds like I will heat the pre-charge syrup and the main batch separately. I have a small burner that I use for my bottler. I'll use that to heat 3 gallons of pre-charge syrup with DE. At the same time, I'll have the rest of this unfiltered batch (7-8 gal) in the 16 gal pot on the turkey fryer. I'll mix DE in that batch as well. I will re-circulate the pre-charge syrup back to itself until it is clear then start filtering the main batch.

By the way, I have a 7", 4-plate CDL/WesFab. It has a 1/2" diaphragm pump. In their directions they have me use 4 cups of DE with 3 gallons of pre-charge hot water and then "occasionally add" 1 cup per 5 gallons to the rest of the batch.

Switching from the pre-charge to the main batch is where I have a couple of questions. Is it okay to shut off the press for a few seconds while I move the hoses from the pre-charge to the main batch? Or for that matter, whenever switching from recirculating in the unfiltered batch to the bottler? Should I avoid sucking air into the press as I switch over?

Can I let syrup that is already clear recirculate indefinitely as I get the syrup through the press up to 185-190?

[Sugarmaker]

Sean,
Sounds like your getting set up! Not sure any of my comments will help??
I filter syrup using DE just about like the instructions for your 4 plate.
Not the same press as yours but as an example: I used about 4 cups in 8 gallons of syrup that was setting warm in a draw off container at the press. mixed that DE in and let it circulate till clear. Then on the next draws of syrup maybe a gallon I would add maybe 1/2 cup of DE. Start the press and run that through. Shut off the filter press and wait for the next hot batch. Did 24 gallons that way over about 4 hours boil time a couple days ago. This is of course going to vary with the amount of sugarsand in your syrup.
You will need to also watch your pressure and maybe use the bypass a little too?
Maybe I am cheap, ok I am. I use a 5 gallon bucket of DE for the season of 150 gallons of syrup.
Regards,
Chris

[mainebackswoodssyrup]

Yes, you can shut it off while you move hoses around. Sucking air is more of an issue with a gear pump than an air pump but avoid it if you can. We recirculate the syrup for a few minutes to get the press warmed up and the charge of DE onto the plates. So always recirculate….check the plates with your hands to see if they are hot. Be careful, they will get very hot.

[maple flats]

Never try to filter cold syrup, it must always be filtered hot. This is how I do it and never have an issue, I have a 7" 5 plate (5 hollow plates plus waffle plates, 10 individual filter papers):
I heat the syrup to 205-210F, then I draw 3-4 gal of hot syrup into my mixing pot. I add 1.5-2 cups DE, mix and then pump it thru the filter press pump and bypass it back to the mixing pot for 20-30 seconds. That helps ensure complete mixing. I then open the filter ball valve and close the bypass valve, sending the filtered syrup back to the mixing pot. I watch the syrup as it flows out of the hose. When it starts to "sparkle" I open the by pass valve, close the filter valve and then hook the 180 bend that discharges filtered syrup over the top edge of the bottler (or into a barrel). When that batch is finished I draw more hot syrup into the mixing pot. In my case that pot holds almost 7 gal, I fill it to 5-6 gal. I then add about 1.25 cups DE, stir, run thru pump and back to the mix pot for about 20-30 seconds again, then I open the filter valve and close the bypass valve. No need to do the extra step because the filter papers are already coated with DE and the filtered syrup discharge is already sending the syrup to the bottler (or a barrel). If you have more syrup to filter, repeat until finished or whatever you are sending the syrup to is full. My bottler is a water jacketed bottler, and before I start sending syrup to it, I turn it on and have it hot. The filtering will cool off the syrup, but my bottler brings it back up to 185-187F. I'm then ready to bottle, after I verify density using my Murphy Cup and Hydrometer, I then grade it, record the grade, mark the sample couvette (I use a Hanna Checker which gives the % of light passing thru the test vial called a couvette) then I proceed to bottle or jug the syrup. Always bottle at least 180F but not over 190F. Having filtered it much hotter you will not get more niter forming.
However, when I repack syrup that was filtered and bulk packed (into a barrel or other bulk container) I do it a little differently. I heat it to 175-180, then filter as before, but after the filter papers are coated, I only add about 3/4 cup DE on each additional batch. Not heating it to the 205-210 helps keep the grade, the more you heat it the darker it will get and on repack syrup I want to get the grade it was when packed in bulk. That usually works, but if it was on the darker side of whatever grade it was when bulk packed, it may end up on the light side of the next darker grade.

[SeanD]

Thanks everyone for the input. I ran the filter press tonight and I think I was successful. I used the steps I mentioned above - though I have to figure out how to manage the space around the press, turkey fryer, etc. so I'm not scrambling around to get what I need.

There were a couple of scary parts like when I thought I broke the pump. It had a funny sound and nothing was being pulled or pushed out. It turns out the suction hose had sucked onto the bottom of the pot.

Then, more than once, as I was adjusting the suction hose, I pulled it above the syrup and it sucked air. The press didn't like that. The press started cavitating and the pressure gauge needle was swinging so wildly it was a blur. Eventually it settled down.

I think having a small press helped me with the temperatures. Even with it being 35 in the sugarhouse, the press heated up pretty easily and I was putting 185-187 deg. syrup into my bulk containers.

When I broke the press down, all the papers were intact and the cakes of DE were evenly spread out amongst all the plates.

Questions:
The syrup coming out seemed clear almost immediately, but I continued to recirculate because I thought it could not work possibly that quickly. I was just kind of guessing at how long to keep going. How long does pre-charging and/or getting to clear syrup usually take? Is a couple of minutes really possible?

My press directions say to stay below 80 PSI. It sat at 30 PSI until I got the air in there and it climbed to 60 PSI. I opened the bypass to control it. Could I have just let it work at 60 PSI?
Is there an ideal pressure to aim for?

Can the papers and DE go into the compost pile?

I'm sure I'll have more questions as I get past the basics. Thanks again for all the input. It was a big help.

[maple flats]

The question of how much pressure likely depends on the press. When I was first using a filter press I was told that it should be kept at 40PSI or under, not because the press would fail but because a paper could fail and let DE into the filtered syrup. I have a Lapierre 7" press, the dealer who told me to keep the pressure at or below 40psi was a Leader dealer. Since then I think the only press I've heard that can be run at a higher pressure is the Leader clear press, according to a Leader salesman, because of the design that supports the filter papers in the clear press.
In the other presses, a waffle plate supports the filter papers, which is much coarser support, while the Leader clear has a SS support with much smaller holes (but lots more holes) thus allowing higher pressure because the filter papers are better supported.