Digital Equipment Corporation - Westfield, MA
Digital Equipment Corporation (DEC) Enclosures improved its paint and waste operation in the production shop by installing an automated painting system. The previous four-booth, three-shift operation evolved to an eight-booth, one-shift operation while meeting EPA and state regulations. DEC reduced the volatile organic compound (VOC) emissions while increasing production line
Using the new system, the enamel painting (high solid
paint) is conducted in the booths presented in Figure 3-1: (1-2 bell system), (3-4 electrostatic), (5-6 manual touch-up), and (7-8 robotic texturing). High quality parts are produced while cutting paint consumption to a minimum. The process requires two hours for a complete cycle of the overhead conveyor, and employees are not required to wear painting masks.
Paint sludge is dewatered using centrifuges. This process is the most effective means of monitoring and controlling the paint solid waste. The EPA and state regulations allow DEC 100 tons of VOC emissions per year. Since the new paint system has been installed, VOC emissions have been reduced from 77 tons to 14 tons per year. The sludge is then biologically treated by Laidlaw Environmental and safely disposed of, reducing disposal cost by $400 per drum.
The DEC waste water treatment system is monitored by the Automated Industrial Monitoring (AIM) security system which monitors the pH in waste water. The AIM system layers over the Allen Bradley Paint Line control system to interface DEC-developed software to distribute alarms to various stations and through E-Mail to key personnel. The system also automatically dispenses acid or base to balance waste water pH within the acceptable range. Alarm distribution is tailored to the needs of individual monitoring stations. The DEC facility is audited twice a year to ensure that the environmental standards are met.