Into the woods by 5:30 AM to cook. It was cold overnight: low to mid-20s. Forgot to drain the line from the storage tank to the R/O. It had slushy ice. The R/O feed pump would run, but the high pressure pump wouldn’t start until that ice was removed because there wasn’t enough sap flow to sustain the pump. It was 7:15 AM before the R/O was going.
The R/O was not preforming. The pH wash didn’t restore performance. We limped along until 11:00 AM then swapped from the FilmTec membrane to the CDL membrane. The spare membrane didn’t preform much better. Both the concentrate and permeate were under .5 gal/min. Likely closer to 0.2 gal/min. The gauge doesn’t have graduations for anything less than .5 gal/min.
We checked the permeate: no sugar in it. Approximately 3.5 Brix on the concentrate. If the flow was higher we could even tolerate the lower Brix. The R/O is rated at 125 gal/hr. Real world is 90 to 100 gal/hr. We were getting 25-30 gal/hr.
Gave up on the R/O by 1:00 PM to concentrate on cooking old style. Dividing attention between the R/O and firing diminishes effectiveness of both. This became a 14 ½ hour day. If the R/O performed to specifications, it should have been a six to seven hour day.
After three batches into the milk can, we returned to amber color as the sap from the warm days was cooked off.
Sunny and mid-30s by afternoon. Some tress dripped, but we have to abandon that sap. Didn’t have the resources to collect and with the forecast snowstorm, couldn’t cook it.
Since replacing the Grundfos feed pump with the Goulds feed pump three seasons ago, we’ve had performance problems with R/O. We suspect the Goulds pump is over-sized for a single 4” membrane and pushes more sap through then the re-circulation pump can handle. We’ll have down time this week because of the snowstorm and then cold weather with single digits at night, and plan to investigate how these pump specifications differ.
The day cooking.
7:15 AM R/O start
8:00 AM 2 3/4″
8:20 AM batch
9:00 AM 4 1/4″
10:00 AM 4 ¼”
10:15 AM batch
11:00 AM 4″
11:00 AM switch to CDL membrane
11:35 AM resume R/O
12:00 PM 4″
12:55 PM batch
1:05 PM stopped R/O
2:00 PM 3 3/4″
3:00 PM 1 1/4″
3:10 PM batch, amber color returned
4:00 PM 8″ raw sap
5:00 PM 6 ½”
5:35 PM batch
6:00 PM 4 1/2″
7:00 PM 2 1/2″
7:30 PM 2″
7:45 Pm done
Back to the farmhouse by 8:00 PM.
Blizzard warning in effect for tomorrow through Monday. 8”-18” forecast with winds 40-50 mph. We are on the trailing edge of the storm. 18”-24” expected 50 miles to the North in the center of the storm track.