Baldwin Longlifefiltration LCM/LDM

(NPES International E-commerce Website, January 22, 2008)  In this age of environmental awareness, manufacturers have become hyper-aware of their waste. In recent years, the general principle that the polluter pays has meant plenty of printers have had to take account of hefty payments to waste disposal companies. Just a decade ago, the same waste would simply have gone into the bin or down the drain. There’s “brass in muck”, as the saying goes, and suddenly the spotlight is on technologies that reclaim, recycle and minimise quantities of waste; particularly ‘special’ waste with hazardous, toxic or otherwise restricted components that can’t be disposed of in the normal way.

Baldwin Longlifefiltration LCM/LDM: ink build-up is reduced thanks to fewer pollutants reaching the dampening system

Pressroom consumables have attracted special attention. This is partly due to the chemistry used on-press being expensive and, therefore, it pays to minimise their use. Also, waste press chemistry – containing isopropyl alcohol (IPA), traces of ink and other additives – attracts a cost for disposal. The more you throw out, the more you pay. Baldwin, the global press ancillaries developer, is hoping its new web-offset fount solution management system, the LCM/LDM, has a bright future with web houses currently paying tens of thousands a year to dispose of their waste press chemistry.

"It’s an all-round winner for web printers," says Baldwin director of fluid and temperature management Wolfgang Prem. “It saves money, it’s better for the environment, it improves print quality and press productivity levels and it can pay for itself in a very short timescale.”

Long-term development

The LCM/LDM technology has been developed over the past four years and comprises two units that can either work together, or separately. The LCM is a filtration device that filters the fount solution to take out contamination. The LDM is a treatment unit that treats the contaminant residue to reduce its volume and reclaim the water it’s mixed with. The two together – one LDM unit can handle the output of several LCMs – make for a complete closed-loop filtration and treatment system, which can pay for itself in as little as three months, according to Baldwin.

In use, the average dampening system on a coldset or heatset web-offset press picks up a variety of contaminants, including ink residue, paper fibres, general ambient dirt, detergent and organic impurities, such as bacteria and algae. The LCM filtration unit works in a sidestream loop, sucking dampening mix from the circulator and feeding it through a metre-long ceramic membrane tube in a cross-flow motion. After the tube is a restrictor valve, which exerts a pressure on the membrane and ensures all the dampening solution passes through. The filtered solution is then pumped back into the circulation unit, while the waste residue remains in the LCM for disposal.

Reducing volume

The LDM works by evacuating the residue from the LCM unit and putting it into a chamber lined with a mineral known as Bentonite, which was originally used as a medicine by Native Americans. Bentonite produces a ‘flocking’ effect, which acts to separate the contaminants from the water in which they’re suspended. The resulting ‘brown’ water can either be reused within the factory – Baldwin is currently talking to a French customer who wants to use it to flush his toilets – or disposed of safely. The contaminant residue itself – now a powder-like concentrate – can be passed to a waste disposal company, "whose bill will be vastly reduced because the volume is a fraction of what it was," adds Prem.

Lurking in the double shadow of cost-savings and environmental box-ticking, are the additional, and not inconsiderable, benefits of print quality, reduced consumable use and reduced press downtime. “The filtration systems normally fitted to a press aren’t usually up to the job,” says Prem. “The way most printers are working is to run until they get so clogged with lint and oils and solvents that they have to stop the press, drain it down, change the water and restart. That’s a lot of downtime, plus a lot of waste fount solution and additive. It’s just not very profitable all round.”

He adds that another big benefit is that ink build-up on the blankets is reduced by having less pollution in the dampening system and, therefore, the intervals between the blanket wash cycle can be longer: after every three or four reels, rather than after every one. It’s also easier to keep the press’s colour parameters stable, because the fount isn’t as contaminated and it’s possible to reduce the amount of IPA or substitute, because one of the functions of the fount additive is to hold contaminants in suspension. If there aren’t as many contaminants, there isn’t as much need for additive. The system is also useful to printers who are running alcohol-free, or with massively reduced alcohol, as it prevents the build-up of algae and bacteria that’s normally taken care of by alcohol.

Inexpensive option

In use, the LCM/LDM is cheap to run. The LCM’s ceramic filters mean there are no costs associated with replacement mats, as with other filtration systems. The LDM, however, does call for the use of filter bags – these hold the concentrated contaminants – of which, Prem says, the average user might get through around one or two a week.
Maintenance is straightforward. The system runs its own automatic integrated cleaning cycle, taking itself offline for an hour to do so. The press can still run while the filtration system cleans itself. “In an hour, you can’t build up enough contamination for it to make any significant difference,” says Prem.

In aiming the LCM/LDM at the web-offset community, Baldwin has gone for the low-hanging fruit of the print industry: this is the sector that generates most volume and, therefore, has most to save from a reclaiming/reducing system. In the 18 months the system has been on the market, there have been 30 worldwide installations at web houses, of which three are in the UK. The biggest UK installation to date has gone to Trinity Mirror’s Birmingham site, where it’s fitted to the 12-unit Goss Colorliner that prints the Daily Mirror and the Sunday Mirror. The Goss’s spray dampening system creates about one litre of waste water per hour of press operation on each couple. The press, which runs almost 24/7, has 96 couples. The waste water disposal cost came to £20,000 a year. On top of that, Trinity also had to pay for its water in the first place and was getting through some 4,000 litres of fount additive each year because around 2% of the additive was lost with the waste dampening mix.

It took half a day for Baldwin to fit the LCM system and the results have been spectacular: a reduction of waste water from about 16,500 litres a month to about 100 litres concentrated waste. The rest will be fed back to the circulator as recycled fountain solution.  The group is now planning to install similar systems at its Cardiff and Teesside plants.