The Clean Manufacturing Game Part 3 of 10

Are You Playing the Clean Manufacturing Game?
A 10 part blog series discussing important aspects of clean manufacturing technology and implementation strategy.

CO2 CleanTech – Part 3 of 10

CO2 clean manufacturing technology (CO2 CleanTech) eliminates or significantly reduces waste generation at the production operation level (i.e., at the source) by modifying manufacturing processes, for example cleaning, assembly processes requiring cleaning, machining operations and thermal spray coating. CO2 CleanTech is uniquely capable of modifying a manufacturing process in numerous ways, as follows:

1. Physically; shape, size, space, application and configuration; and
2. Chemically; solvency, toxicity, wetness, and chemical process.

Owing to CO2’s inherent dry and compatible chemistry, the technology may be implemented directly into a variety of production equipment and process configurations to meet the needs of lean production schemes and product flow constraints, including both existing (aftermarket) and new production implementations.

As an example, replacing conventional surface cleaning agents with CO2’s green chemistry eliminates process inputs such as liquid cleaning solvents, aqueous clean agents, detergents, deionized rinse water, and heated air dryers, among other waste-producing inputs. In another example, CO2-based advanced minimum quantity cooling lubrication (CO2 Machining) replaces flooded cutting fluids and associated waste-producing operations such as fluids management, waste hauling and air pollution control.

Substantial environmental benefits are derived by using CO2 CleanTech. The U.S. Environmental Protection Agency (USEPA) has determined that CO2 is an environmentally benign alternative chemistry for the manufacturing industry because there is no net increase in global warming gases or environmental damage as a result of using CO2. Removing or minimizing the usage of organic compounds such petroleum-derived cutting and cleaning fluids in manufacturing processes and in particular not having to produce as much of these compounds and replacing them with CO2 will lower energy usage, lower emissions of global warming gases, improve water and air quality and natural resource conservation. CO2 is a cost- and performance-effective replacement in a variety of cleaning and machining applications.

Machining and cleaning are two common manufacturing processes, which are typically performed sequentially in a production cycle. Many types of manufacturing wastes are generated in these processes in the form of solvents, water, wastewater, sludge, filters, treatment chemicals, metalworking fluids, air emissions, spills and leaks, damaged equipment, rework or scrap parts, machinery maintenance, cleaner maintenance, boilers, cooling towers, environmental management operations, productivity and energy. Specific examples of precision cleaning and machining activities that produce a waste include:

• Moving products off-line or out of cells to clean them and then returning them back to the line or cell
• Filtering and treating spent alkaline cleaning chemistries
• Monitoring cleaning and machining fluid chemistries
• Rinsing parts
• Drying parts
• Treatment and disposal of spent cleaning and machining agents
• Completing waste hauling manifests
• Environmental reports
• Deionized water treatment
• Rinse water treatment and disposal

Given this, following considers how CO2–enabled machining and cleaning operations can eliminate many of these waste elements:

• Materials selection and productivity: Recycled CO2 itself does not generate waste, does not require environmental management, and eliminates equipment cleaning and maintenance.
• Energy conservation: Using recycled CO2 eliminates the need for additional energy to heat cleaning baths, dry parts, or evaporate and concentrate wastes.
• Waste reduction and elimination: CO2 does not itself become a waste by-product. CO2 eliminates the wasteful consumption, treatment and disposal of water, wastewater and associated solid wastes.
• Air pollution reduction: Recycled CO2 is not considered an air pollutant, is non-toxic and is odorless within the factory atmosphere.
• Space and process step reduction: CO2-enabled cleaning processes can reduce multiple processing steps to a single step and perform in less space, sometimes no extra space is needed if the CO2 process is integrated directly with an existing manufacturing tool such as a bonder, dispenser, or machining tool.

David Jackson is President/CEO of Cleanlogix LLC and serves as the Chief Technology Officer for Cool Clean Technologies, Inc, based in Eagan, MN. He may be reached via e-mail at david.jackson@coolclean.com.

Part 4 of this series gives some examples of how CO2 cleaning technology cleans up the factory.