Category: Other

Evaluation of Paint Booth

A manufacturer wanted to expand their operation of the paint booth. The paint booth’s capacity was limited by the emissions of Hexavalent Chromium.

The existing paint boot had a filtration system to collect the overspray as a primary control device. A previous consultant suggested adding a water scrubber as a secondary control device. They proposed to monitor the discharge water stream to show that the scrubber was in proper operation.

Adding a scrubber as a secondary control device is not an efficient use of control technology. Further, measuring the concentration in the water discharge stream does not effectively measure the control. If the filtration system collected more materials, then the hexavalent chrome going to the scrubber would be reduced and the concentration in the discharge would be less.

I decided to look at the entire process. The paint in the spray booth was a mixture of 3 component paint mixture, which only one has hexavalent chrome.  The Hexavalent Chrome emissions were calculated by assuming all of the Hexavalent Chrome that was in the paint were emitted.

The procedure called for mixing the paint for 30 minutes prior to spraying. I had an independent laboratory test the mixture after 30 minutes. The hexavalent chromium in the combine mixture was reduced to Tri-valent Chrome and considerably less before the mixing of the 3 components. The manufacturer was able to increase the production without adding additional air pollution control devices.

Asbestos Database Structure

In the mid 1980’s to comply with the AHERA regulations, a large southern school district with over 100 individual schools had to manage the inspection and control of the asbestos containing materials. They needed to know the type of material, exact location, its condition and whether it was removed.

A database program was used to manages this information. I was the principle author of the database program. I set up the databases and designed the sorts and printouts. Despite the advancements in computer and software technology, the original program and database still provide the same function. While there have been modifications to the user interface, the school district is still using the original database structure and report function today..

Pressure Relief Valve

An equipment manufacturing company was designing a high-pressure gas test facility in an area that had noise sensitivity issues. This test facility required air pressure relief valves to protect the equipment. Due to the high pressure of the system the calculated relief velocities exceeded the sound barrier and therefore had to be sent through a silencer that did not impede the flow of the relief stream. Calculations were performed that met both the relief requirements and the noise requirements.