The recovery , for direct sale or acidulation, of soap is one of the more consistently overlooked profit centers in modern Kraft mills today. Not only does its sale as soap or after acidulation as crude tall oil (CTO) add dollars directly to the bottom line, but its removal from the liquor stream prior to evaporation greatly enhances evaporator performance.
The quantity of soap available for recovery varies quite a bit and is influenced by many factors. However a range of recovery of 200 - 300 lbs. soap/ton of pine pulp can be used in gauging the efficiency of your operation. If you aciduate your soap onsite, this amounts to a CTO production of 100 - 150 lbs./ ton of pine pulp.
If your soap recovery does not fall into this range, an audit of your operation can produce big dividends. You could expect that this audit would produce the following information:
The quantity of soap available for recovery at your mill.
The quality of the soap that is presently being recovered and recommendations on how to improve it if needed.
If the quantity presently being recovered is less than should be expected, methods of improvement will be explored.
If your mill acidulates soap and sells CTO, the acidulation operation will be audited as well, to determine if opportunities exist to improve the yield of CTO from the soap being recovered.