## Notes on Differences in Collection Operations in the Mineral Wool Industry

23 June 2011 Steve Edris, Thermafiber

The VERTICAL COLLECTION design.

The collection chamber at Thermafiber is 10

- 15 feet long, about 6 feet wide.

At the end of the chamber is a vertical perforated belt moving belt, running at about 300 feet per minute (this is the fastest in the bonded lines)

The cupola produces at the same steady rate, pouring a thin stream of molten rock onto the spinners. Binder is sprayed onto the fibers through ports on the circumference edge of the spinners. Air flow comes from behind (and under cupola) to blow the fibers away from the spinners as they are formed.

A stronger air flow pulls negative on the screen, sucking the now cooled, binder sprayed fibers against the moving vertical screen, forming a mat that is about 1

- 1.5 inches. This screen moves much faster than any other in the industry because it is vertical. Otherwise, you’ d have the fiber mat slumping along the bottom curve.

This design makes a cleaner product that is low in ‘shot’. Shot is ok for some products, but can’t be present in horticultural applications (tomatoes need a uniform density product without ‘shot’, as do other vegetables). The CHOH is not trapped.

The HORIZONTAL COLLECTION design.

Everything is pretty much the same right up to the collection process. In the horizontal collection, the horizontal mat is much thicker. That belt moves at about 50 feet per minute, and CHOH is trapped in a thicker mat. The belt doesn’t have to move fast because you are not working against gravity as you are in the vertical design. However, there are some products you can’t make on a horizontal design. First, the shot remains in the bonded product. That’s okay for the products they make at that company, because that’s mostly insulation products where some amount of shot does not affect the final application. But you couldn’t sell to the horticultural markets with that product.

The DRUM COLLECTION design.

Again, it’s pretty much the same right up to the collection process. But then this is basically a totally different approach

. Instead of spinners and a moving belt, imagine a piece of equipment that looks like your wa shing machine, except turned. The molten rock is poured from the cupola into this big spinning drum, like the inside of your washer. And the little holes in the inside where the water empties out of the washing machine....that’s where the air flows out of the spinning drum carrying with it the threads of mineral wool. Unlike the other two designs, the air flow is already contained within the drum, and it can be directed as an air stream that lends itself well to controls. Out of the holes flow the forming fibers coming out as a loose long flow of fibers that is pulled from the spinning drum. The air stream from the collection process can then be directed to either the hottest part of the cupola stack or to the RTO on the curing oven. Either way, you achi eve really low emissions of the organics in the binder.

## Notes on the Origins and Cause of COS Emissions in Mineral Wool Industry

Chris Bullock, IIG 28 June 2011

IIG is not ‘afraid’ of adding pollution controls. They do NOT support NAIMA’s approach on the SBAR panel. They said the industry group will look stupid and ineffectual going forward with the proposed limits. They do not think industry should get a pass just because they claim to be small. I IG can meet the li mits EPA will be proposing.

They wouldn’t have to install a new RTO. They route their collection emissions to the hottest part of their cupola stack. This causes the formaldehyde, MeOH and phenol to incinerate in the stack before being emitted to the atmo sphere.

IIG has done research to show the source of sulfur is the SLAG....COKE is the source of CO. Coke is not so much a contributor to formation of COS and SO2. They purchase low

- sulfur slag locally so their costs are still low.

Chris Bullock, IIG 28 June 2011

We mine and melt our own rock so we have better control of our inputs. We can melt at higher temperatures. But we have a 50% cost increase to us on our raw materials.

Low sulfur slag is not an option (?)

Oxyge n injection will increase the COS because it burns hotter (?)

We don’t have a sulfur compounds being emitted from our raw materials, because we don’t put sulfur containing raw materials in to start with. In order to have a problem with SO2 or COS, you hav e to have sulfur in your raw materials. We know exactly what we are melting. All the other companies do too, or they ought to. Everybody keeps records of their raw material inputs because you have to do that to keep a consistent and reliable end product

. Where is the leveling of the playing field? We are good environmental stewards. Again, we don’t think industry should get a pass on regulation just because this industry is full of companies that say they are small.