Mayday Graphics

Guide to RO systems for the litho printing industry

Find out how an RO system will benefit your printing business by arranging an on-site consultation – you can make an appointment here.

Reasons for using RO treated water in the print process

One of the most important reasons printers install Reverse Osmosis fitlers is to stablise and maintain a consistant fount solution, without it problems during the printing process begin to rise, leading to poor print quality and failed 'press passes', but these can be overcome by using RO treated water.

Most press manufactures recommend using a water supply with a hardness of 10deg German, normally expressed as 10deg dh.

Throughout most of the East Anglian region, water is considered to be very hard, above 300 mg/l as calcium carbonate.

We expect the unit to work day in day out 365 days a year. We never think about it any more it just happens.

For a more accurate answer you can check water hardness here, results provided by Anglian Water and compare them to the recommended 10deg German above, you'll be surprised how the mains water supply could be affecting the quality of your output.

Rarely water supplies are either this level of hardness or consistent. Hardness will vary according to source of supply, which in many cases day to day will alter as many supplies are fed from ring main systems that draw from geographically different sources.

Seasonal rainfall and many other factors alter hardness as well; water companies are supplying good drinking water and are not concerned with supplying consistent water for printing purposes.

RO is pretty much universally accepted as the best way to ensure water for printing purposes is stable and consistent.

Flow diagram and components of common  Reverse Osmosis units

Sediment filter - removes particles in the water larger than 5 microns in size.
Carbon Filter - removes Chlorine from the water that is damaging to the membrane/s.
High-pressure pump - raises supply pressure to desired level to ensure optimum production of membranes.
Storage tank - stores processed water ready for re hardening in a dark and clean environment that does not support bacteria growth.
Re hardening doser - add synthetic agents to bring the water to desired hardness for printing typically 10-11 German dh.
Water softener - under certain circumstances where a large system is installed or feed water is very hard it is necessary to fit a pre softener to help with production rates and protect membranes lifespan.

Will it work in my pressroom?

Mayday Graphic Products supply Reverse Osmosis systems that are cost effective and can be tailored to work with just one press or the entire pressroom.

Frequently asked questions - FAQ's

Q - Why re-harden RO water?
A - RO water is too soft to print with, without re-hardening ro water will “hunt” for minerals from the paper causing calcium build up on press rollers and “roller stripping” also known as “roller blinding”

Q - Why is RO water corrosive?
A - Reverse Osmosis water is only corrosive under certain feed water conditions and is not corrosive when re-hardened as most good chemical firms add anti corrosive chemicals to their re-hardeners and fountain solutions.

The reason neat RO water is sometimes corrosive is due to the fact that the membranes only remove dissolved solids from the water and not gasses, this will lower the ph of the water making it corrosive when the water is re-hardened this is nullified.

Q - How much waste water is produced?
A - Pure units run on a 50-50 split, so for every litre of production there is a litre of waste, this can be reduced on request. Many competitors units have a much higher waste level, commonly 4 litres of waste to 1 litre of production. We can increase the production rate to 75% with the addition of a softening unit.

Q - Can you use waste water?
A - Only for grey water applications, toilet cisterns etc, under no circumstances should it be used for human consumption.

Q - Can the wastewater go in regular drainage?
A - Yes but not into storm drainage

Why printers should install an RO system in the Pressroom?

• Press rollers have a longer lifespan when using RO water.
  
• Less alcohol is required when using RO water.
  
• Print is sharper and cleaner with RO water.
  
• Consistent water supply means better monitoring of potential problems.
  

Why choose Mayday Graphic Products for Reverse Osmosis units.

• There is often no need for a pre softener with units from Mayday Graphic Products.
• Extensive experience of reverse osmosis installations than other UK companys.
• Reliability, 98% of units installed over the last 10 years are still in operation.
• Units are extendable and grow as your company grows.
• Extremly competitive pricing within the litho sector.
• Consistent supply of treated water.
• Better for the environment - lower waste water is produced from our systems, compared to other manufacturers.