I had seen a presentation at the 2011 NGWA Expo by Mr. Reinhard Klause of Sigmund Lindner, a German manufacturer of precision glass bead products, on an innovative well-design technology—the use of glass beads as filter pack material. I thought the idea merited further discussion, so when I heard that Reinhard was going to visit the Pacific Northwest, my colleagues and I scrambled to organize a seminar.
To maximize the value of the seminar, we invited a broad cross-section of the groundwater community, including drilling contractors, water utilities, well design consultants, the regulatory community, and materials suppliers. We were only able to provide a few days’ notice, but people responded quickly to our invitation. Thank you to all who dropped everything to “come to the party.” I would also like to thank Burt Clothier (RN) and Bill Lum (Ecology) for working to qualify the event for continuing education credits for our driller guests and to Stan French and John Bowman (Lakehaven Utility District) for providing access to the Lakehaven Center meeting facility in Federal Way.
After a few words from me to make sure people knew this was a working seminar and that they were invited because I knew them to be “not quiet” at meetings, Reinhard provided an hour-and-a-half presentation in which he described both the product he sells (known as SiLi Beads) and, more importantly, the research accomplished with regard to its use as a gravel pack medium in water wells.
Rather than go into detail about the full content of the presentation, we have made his presentation available here along with technical specifications for the beads. To summarize, Sigmund Lindner (SiLi – get it) developed a line of glass beads to be used in place of the sand and gravel materials currently used as filter pack material in well construction. The beads offer a perfect sphere with a surface smoothness that isn’t available in natural materials. Coupled with the inert nature of glass, the unusually smooth surface inherently offers fewer opportunities for the initiation of both chemical coating (encrustation) and biological growth (biofouling) throughout the life of a well.
So, what are the down sides?
- Price—the beads currently cost five times as much as typical sand pack material.
- Availability—without local distributors, several audience members raised concerns about getting the material in a timely manner.
- Design Confidence—are the rules of thumb used in typical designs appropriate to such a “perfect pack?”
Comparing the cost to the sand packs presently used is an inappropriately myopic view in my opinion. When looking at the cost in the context of a complete well construction project, it is much less of an issue. Further, if one considers Rienhard’s assertion that placement of the (essentially dust-free) beads is more efficient than traditional sand, a saving in rig time can be gained. Apparently, the beads flow like a fluid and tend not to bridge in the annular space into which they must be placed. Reinhard also indicated (and their research appears to bear out) that well development is accomplished more quickly and efficiently because the energy of development is more readily transmitted to the natural formation through the glass beads as opposed to traditional pack. If these factors are true, then the use of glass beads could be cheaper when considering overall project cost. Reinhard also claims that wells using SiLi beads for a pack are more efficient, so the potential economic benefits would extend beyond the construction phase and throughout the operational life of the well.
When the issue of timely delivery of the beads was discussed, it was more of a “we are working on it” response. However, a discussion overheard between Greg Esborg of Preferred Pump and Equipment (a provider of material for drilling projects) and Reinhard seems to indicate that the details of local representation and supply might not be as daunting as a German supplier might imply. Reinhard stated that Sigmund Lindner would make the product available on consignment, which should make it easier to get suppliers to carry the product. The issue of initial supply for construction seems like a solvable logistics problem. The issue of what to do when your original pack order falls a little bit short of the required amount, and a small quantity of “top-off” pack is needed, could prove more difficult. Reinhard suggested that a supplier with adequate warehouse space could keep a top-off supply of variously-sized beads and alleviate that concern.
Both Larry West (Shannon & Wilson) and I had some discomfort with using our standard design calculations with the “perfect pack” material. To paraphrase, us two old men were saying, “But I’m afraid of new stuff.” Reinhard answered, “There, there. It will be alright. I will hold your hand until you are not scared.” (Sorry for characterizing the two of us as cowards, Larry). In all seriousness, when applying such new technology to a project that often has a six-figure cost, the idea of taking new risks is a concern. Mr. Klaus seemed confident that his research demonstrates the use of standard design techniques translates well to the glass bead application. It was clear that they had given some thought and more than a little research to address our concern.
All-in-all the seminar achieved its intended purpose. The audience received adequate information to discuss the use of glass beads in Puget Sound area wells as an informed group. Reinhard got to hear from the full spectrum of interested parties within the groundwater community of our region, and the discussion seemed sufficiently enthusiastic that the concept received a good initiation.
For those of you who could not attend, or those of you who are first hearing about glass-bead well construction, feel free to add your comments and questions. We would be happy to pass on the discussions to Reinhard and his crew. If any of you decide to try this design option, please let us know how it works out so that we might learn vicariously through your experience.
We look forward to the continuing discussion.