Water reuse system incorporating vacuum pump sealing water in a zero discharge process

摘要

A papermaking water system utilizing vacuum pump sealing water and having a zero sealing water discharge. A group of water seal vacuum pumps are used in a papermaking machine to generate subatmospheric pressure in suction equipment and thereby extract water from a wet paper web. During operation of the vacuum pumps, the sealing water is heated and the heated water is discharged to a cooling tower to cool the water which is then recirculated to the vacuum pumps. Steam from a generating plant is supplied to the dryer drums in the dryer section of the papermaking machine, and the steam condensate is combined with the heated sealing water flowing to the cooling tower. By using steam condensate as makeup water, no ionic buildup will occur in the closed system, and high quality water is withdrawn from the closed system and may be used in other sections of the papermaking machine, so that there is no discharge of sealing water to the sewer system.