poor separation in vacuum belt filter ( VBF )
poor separation in vacuum belt filter ( VBF )
(OP)
Hi, All
I have encountered problem in vacuum belt filter ( VBF )due to poor separation. Feed is slurry which consists of carboxy methyl cellulose ( CMC ), salt and isoprophil alcohol ( IPA ). CMC is product which has to be extracted from IPA and salt in VBF by IPA solution. It comes out from VBF must be less than 0.5 % IPA. But it is impossible that level could be achieved even though adjustment feed and IPA concentration have been conducted. It may be occured that product have low viscosity and high degree of substitution ( DS ). Does any expert can suggest me to solve this problem.
I have encountered problem in vacuum belt filter ( VBF )due to poor separation. Feed is slurry which consists of carboxy methyl cellulose ( CMC ), salt and isoprophil alcohol ( IPA ). CMC is product which has to be extracted from IPA and salt in VBF by IPA solution. It comes out from VBF must be less than 0.5 % IPA. But it is impossible that level could be achieved even though adjustment feed and IPA concentration have been conducted. It may be occured that product have low viscosity and high degree of substitution ( DS ). Does any expert can suggest me to solve this problem.





RE: poor separation in vacuum belt filter ( VBF )
The problem could be that your system capacity is consummed pumping out air that leaks in instead of pumping out vaporized CMC. The test for leaks involves quantifying the leak rate by pumping down the system to lowest vacuum value and observing the pressure rise after the system is shut in. The system will need to be down for this test. Take the time basis and the pressure difference, total system volume (piping, vessel, etc), to calculate a volume air rate. The desired capacity for vapor plus air should then be within the pumps capacity. If not then your system is pumping the air instead of product. The need for this test can be verified if a condensing unit is downstream and the pound rate of recovered product is below required. Adequate mixing should help with viscosity problems
Hope this helps.
RE: poor separation in vacuum belt filter ( VBF )
DS can indeed alter the water-solubility and negativity of CMC, but it is largely the MW of the original starting cellulose that determines the viscosity.