Glycerine Refining
A. Purification
The Sweet Water Purification process involves sweet water coming from the splitting tower being heated to around 60 – 70 degrees Celsius using the steam in the Heater. The water is then freed to the reaction vessel where various chemicals are added like Alum, Sodium Hydroxide, Ferric Chloride and HCl.
A process of agitation follows which is actioned with air in the reaction vessel. The chemicals react with the impurities in the sweet water and form a precipitate. Subsequently the water is passed through a filter where crude glycerine is passed through the filter pores and collected in an intermediate tank. All precipitated impurities are captured by the filter cloths, which can be changed and recycled regularly.
A process of agitation follows which is actioned with air in the reaction vessel. The chemicals react with the impurities in the sweet water and form a precipitate. Subsequently the water is passed through a filter where crude glycerine is passed through the filter pores and collected in an intermediate tank. All precipitated impurities are captured by the filter cloths, which can be changed and recycled regularly.
B. Evaporation
Sweet Water Concentration is carried out after the Purification process. A pump moves the water from the purification chamber to the concentration chamber. The glycerine water is passed through a feed heater and further on to the 1st effect Evaporator. The temperature is increased to around 130 degrees Celsius in the 1st effect evaporator with steam at about 8 – 10 bar. The moisture is then removed, and the sweet water is returned to the 1st effect evaporator for heating.
Thereon the sweet water is passed to the 2nd and 3rd evaporators sequentially where the temperatures are maintained at 80 and 50 degrees Celsius respectively. The condensate is collected in the condensate receiver and is reused as process water for the Splitting tower.
Thereon the sweet water is passed to the 2nd and 3rd evaporators sequentially where the temperatures are maintained at 80 and 50 degrees Celsius respectively. The condensate is collected in the condensate receiver and is reused as process water for the Splitting tower.
C. Distillation
The distillation is based on a packed tower where the glycerine is distilled, fractionated to separate both heavy and light boiling impurities, and condensed.
Yellowish glycerine is condensed in a separate scrubber. Deodorisation can be supplied according to the material being processed. Refining is continuous on three in line bleachers.
The glycerol solutions from the splitting with preconcentration process may contain up to 15 parts per 25 of glycerol. They are distilled in Packed Columns where impurities (both large, granulated and dissolved) are separated, and pure glycerine is distilled off.
Yellowish glycerine is condensed in a separate scrubber. Deodorisation can be supplied according to the material being processed. Refining is continuous on three in line bleachers.
The glycerol solutions from the splitting with preconcentration process may contain up to 15 parts per 25 of glycerol. They are distilled in Packed Columns where impurities (both large, granulated and dissolved) are separated, and pure glycerine is distilled off.