Finding a sustainable solution for cutting fluid waste disposal
The high volume of metal cutting performed by over 40 CNC Milling and Turning machine at Inflite's Stansted facility created a number of issues with cutting fluid waste disposal and degradation.
Previously, tramp oil could potentially sit on top of coolant with the CNC machine tools and cause degradation and contamination by allowing bacteria to breed within the coolant. When this happens the machine is drained and the contaminated coolant needs to be disposed of to stop the risk of bacteria spreading to other machines. Cutting fluids were drained from large swarf skips and containers into IBC for storage, then if not reused (risky due to contamination) the waste fluid was subsequently disposed of and taken away for disposal by specialist contractors. This proved to be expensive and not in keeping with Inflite’s desire to reduce environmental waste. A solution had to be found.
Investment by Inflite
To remove the tramp oil and clean the coolant Inflite invested in belt driven tramp oil belt skimmers that sit in the machine tools coolant tank to constantly collect the tramp oil that accumulates. These units are to remove as much tramp oil as possible from the coolant within the machine tools. Inflite further invested in a CARDEV CCS500-B coolant cleaning station, and four RUF Briquetting machines to both better handle the processing of swarf, and significantly reduce the volume of waste cutting fluid.
Working with ETL Fluid Experts, it arrived at a very favourable solution. Swarf is collected from the milling process in a standardised container. As the chippings build in the container, any coolant within the swarf that drops to the bottom of the container is collected and returned to the CNC mill via a vacuum system.
Inflite’s four RUF Briquetting machines
Inflite’s four RUF Briquetting machines then subsequently compact the swarf into small pucks. This briquetting has reduced the volume of the swarf by 90% and removes 97% of any residual coolant within the swarf. Any further tramp oil that still remains after the briquetting process is removed using a CARDEV T700 Portable Tramp Oil Removal unit.
The coolant is filtered to remove any fine solids that may still be present, and then sent to the CARDEV CCS500-B coolant cleaning station. The unit passes the waste coolant over an Ozone generator that revitalises the coolant and kills off any harmful bacteria and the agitation releases any remaining tramp oil. This coolant is now sent to a holding tank, via another set of polypropylene filters where it is held ready to be used again by the CARDEV mixing station. Once it has undergone the cleaning process, coolant is then available to be used again and the CNC machine tools receive a top up of coolant. This has had a positive impact on the amount of coolant we have to dispose of due to contamination.
“The CARDEV recycling and mixing unit, tramp oil skimmer and RUF Briquetting machines have all helped Inflite in achieving our goal of reducing environmental impact, health impact to machine tool operations and in reducing costs incurred. Meaning a more competitive price can be offered to our customers on CNC milling.”
Will Stephens – CEO
“The system we have installed at Inflite is both cost effective and environmentally positive and with the automation of the entire process it also eliminates many of the familiar health and safety hazards that come with conventional coolant mixing and disposal. The major advantage of the CARDEV system is the relative low-cost of the system, making it a viable option for most businesses, we have installations where the customer has as few as five machine tools and the payback and advantages that are being gained are playing an important part in driving their manufacturing costs down and making them more competitive.”
Darren Thomas, Sales Manager – ETL Fluid Experts.