Establishing and maintaining an effective and cost-efficient process water recycling system requires consideration of a few essential points. Without the proper compounds, additives, and monitoring, even a well-designed piece of centrifuge technology is bound to falter and, eventually, fail.
Rosler has extensive experience in mass finishing, including designing and manufacturing equipment, fine-tuning processes, and supplying the right consumables for a variety of processes. With our knowledge, preconditions and consumables can be calibrated for maximum process efficiency.
Special Recycling Compounds
Mass finishing compounds fulfill numerous tasks such as degreasing/de-oiling work pieces, burnishing/brightening surfaces, and providing a temporary corrosion protection. Above all though, the primary task of the compounds is to keep the media and work pieces clean to achieve the desired finishing goals and keep the mass finishing process stable.
Combining the direction of rotation and centrifugal force, Rosler’scentrifuge technology takes advantage of the weight difference between the liquid phase and the solids in the process water to separate “dirty” solid particles from clean, reusable process water.
The effectiveness of this technology lies in the centrifugal force that is created. For example, a modern fighter jet develops a G-force of about 10-15 while a high-speed centrifuge drum generates a force of more than 2,000 G.
The physics of centrifuge technology combined with mass finishing equipment creates efficient and ecologically sound manufacturing processes, albeit with some key limitations.
Collection by Force
The solids, primarily consisting of media and, to a lesser degree, of metal fines from the work pieces, found within “dirty” process water are heavier than the water itself. As the drum spins, heavier solids are deposited on the drum wall in the form of sludge, whereas the lighter-weight liquid remains on the inside of the drum. With the addition of special cleaning additives known as flocculants, even oil carried into the mass finishing process can be removed from the process water.
During mass finishing, the process water injected into the finishing machine is contaminated with the chemical ingredients of the compounds, fines from the grinding or polishing media, and metal fines from the work pieces.
In case of ball burnishing, when acidic or alkaline compounds are used, the process water can also contain dissolved metals or be alkaline or acidic. Or, for example, when the work pieces are covered with oil from machining or stamping operations, the water can even be contaminated with oil.
Rosler has developed a series of closed-loop, water circulation systems using centrifuge technology to remove these contaminants regardless of their origin and allow clean process water to be reused and/or safely discharged. In addition to offering more effective work piece processing, cleaning process water saves money and the environment through reduced consumption, compound usage, disposal costs, and regulations.
Technology has transformed almost every aspect of life and the shop floor is no exception. As explored in previous Automation Blog Series posts, Rosler Metal Finishing believes automation represents the new norm in mass finishing and shot blasting. In the face of increasing competition, manufacturing interests will continue to demand lower cost, higher efficiency, and greater flexibility from their chosen surface finishing partner.
Though it would appear that any downsides of automation are outweighed by its benefits, there’s a delicate balance to be struck when it comes to a symbiotic relationship with the world outside of the machine. Having previously discussed how human effort and ingenuity will work in harmony with automated processes, we now turn our attention to environmental considerations—namely, how automated machines used in mass finishing and shot blasting can impact the earth’s resources, and how manufacturers can mitigate that impact.
The International Institute for Sustainable Development notes that the rise of automation has thrust us into a “Fourth Industrial Revolution,” citing energy use, resource use, and ecosystems as the three most critical factors to watch as more automated processes are implemented.
These are important considerations, given that manufacturers often are targeted in headlines about waterway pollution and even global warming, but responsible manufacturing practices can help avoid the most egregious impacts and keep manufacturing operations in compliance.
Mass finishing techniques are often used to uniformly prepare and finish work-pieces, but the compounds and liquids used to remove fines and other debris from work-pieces must be dealt with to ensure a repeatable process application. Cleaning and/or recycling waste water produced in the mass finishing process is easily achieved with centrifuge technology and provides opportunities to be more environmentally responsible and save money in the form of reduced labor and materials (cleaning agents and compounds).
Industrial process water re-circulation is the preferred water treatment method for so many applications. Process water recycling systems can be connected to virtually any wet processing machine (and multiples of) and can make significant savings by way of reduced volumes of water (and compounds) used and their associated disposal costs.
A question that faces many mass finishing and wet or vapour blast machine users, as well as those using machining centres and pre-painting wash plants is how do I separate process liquids and solids from each other?
Process liquid separation and recirculation provide opportunities to save, be environmentally responsible and be more economic.