Aqueous processing method for flexographic printing plates

A system for processing a photosensitive flexographic printing plate having a latent image formed by image-wise exposure of an aqueous solution-processable photopolymer, comprising:

• a platen for receiving the photosensitive flexographic printing plate having the latent image that has at least one exposed portion with hardened photopolymer and at least one unexposed portion with unhardened photopolymer;
• a main processing unit for forming a relief image from the latent image, the main processing unit comprising:
• a pump for contacting a first aqueous processing solution including a first dispersing agent with the latent image;
• a mechanical cleaning system including one or more brushes for mechanically cleaning the latent image in the presence of the first aqueous processing solution;
• and
• a collection system for collecting a first used aqueous processing solution having the photopolymer;
• a secondary processing unit comprising:
• a second pump for washing the relief image with a second aqueous processing solution including a second dispersing agent, the second aqueous processing solution being devoid of the photopolymer;
• and
• a second collection system for collecting a second used aqueous processing solution having the photopolymer;
• a processing solution tank fluidly coupled to the collection system and the second collection system and configured to combine the first used aqueous processing solution with the second used aqueous processing solution to form a combined used aqueous processing solution in the processing solution tank, wherein the processing solution tank is fluidly coupled with the pump of the main processing unit and the first aqueous processing solution is the combined used aqueous processing solution in the processing solution tank once formed;
• a processing solution removal system fluidly coupled with the processing solution tank, the processing solution removal system comprising:
• a holding tank configured for receiving the combined used aqueous processing solution;
• and
• a conduit from the processing solution tank to the holding tank,
• wherein the processing solution tank includes the combined used aqueous processing solution at less than a predefined maximum volume and having the photopolymer at less than a predefined maximum concentration.