Alkaline effluent solution treating process

A process for treating an alkaline solution obtained from lithographic printing plate processing comprising admixing at least one alkaline solution and at least one aqueous waste water solution to obtain an aqueous alkaline solution, and admixing the resultant aqueous alkaline solution with at least one acidic solution in a volume ratio in the range of about 1 part alkaline:0.2-4.0 parts acidic:≧50 parts aqueous, thereby neutralizing the alkaline solution to avoid the formation of unacceptable gels, sludge, or precipitates, and to obtain a neutralized discharge solution having a pH in the range of about 5 to 11.5.

A process for treating an alkaline effluent solution obtained from lithographic printing plate processing, comprising admixing the alkaline effluent solution and at least one acidic solution in the presence of at least one aqueous solution which is a waste water stream obtained from lithographic printing plate processing in a volume ratio of about 1 part alkaline:0.2-4.0 parts acidic:≧50 parts aqueous, thereby neutralizing the alkaline solution to avoid the formation of unacceptable gels, sludge, or precipitates, and to obtain a neutralized discharge solution having a pH in the range of about 5.0 to 11.5.

A process for treating an alkaline effluent solution obtained from lithographic printing plate processing, comprising admixing the alkaline effluent solution and at least one aqueous waste water solution which is a waste water stream obtained from lithographic printing plate processing to obtain an aqueous alkaline solution, and admixing the resultant aqueous alkaline solution with at least one acidic solution in a volume ratio of about 1 part alkaline:0.2-4.0 parts acidic:≧50 parts aqueous, thereby neutralizing the alkaline solution to avoid the formation of unacceptable gels, sludge, or precipitates, and to obtain a neutralized discharge solution having a pH in the range of about 5.0 to 11.5.

A method of controlling a process for treating an alkaline effluent solution obtained from lithographic printing plate processing comprising:

• providing at least one aqueous alkaline solution to a neutralization tank comprising means for monitoring the level of discharge solution contained therein and means for measuring the pH of the discharge solution contained therein;
• measuring the pH of the discharge solution in the neutralization tank, and converting the measurement to a signal;
• transmitting the signal to means for introducing at least one acidic solution into the neutralization tank, thereby causing such means to introduce acidic solution into the neutralization tank in a volume ratio of about 1 part alkaline:0.2-4.0 parts acidic:≧50 parts aqueous, thereby neutralizing the aqueous solution to avoid the formation of unacceptable gels, sludge, or precipitates, and maintaining the pH of the neutralized discharge solution at a pH of about 5.0 to 11.5.