Data gathering began at the committee’s first meeting, in July 2011 in Richmond, Kentucky. The committee received technical information on the BGCAPP WRS and engaged in extensive discussions with BGCAPP staff. A follow-up teleconference was held with BGCAPP staff members during the committee’s second meeting, in September 2011. Additionally, BGCAPP staff and their vendor answered several sets of written questions from the committee.
During discussions with you and your staff, it was agreed that visiting other vendors of reverse osmosis water treatment systems was not necessary because the committee membership had adequate experience with water treatment and recovery systems to complete its work without conducting such visits. Furthermore, the sponsor and committee agreed that, since no other treatment facilities process effluent streams with a composition similar to the effluent streams that the BGCAPP WRS will treat, no useful comparison could be drawn from existing industrial operations. The committee did not review the SCWO design. It accepted the data on SCWO effluents provided by the sponsor and evaluated the planned WRS on the basis of those data, although it did note differences between the parameters used for the calculations made using the ROSA RO process modeling software and the data from the tests conducted with actual blended SCWO effluents. The committee also took the following limitations into account during its work:
The study’s scope is defined to encompass operations that begin with the arrival of SCWO effluent and blowdown waters at the WRS for treatment and end with the RO system effluents leaving the WRS to be stored in tanks. The study is organized to describe and review the system at a high level as the effluent streams proceed from the water-softening step through the pretreatment steps and finally to the RO system. The materials of construction are reviewed in the “Materials of Construction” section of the report.
The committee commends the decision to reuse process water, reducing the overall demand for water made by the plant. The committee believes that, as long as the WRS functions properly and meets its treatment goals, the recovered water will be suitable for reuse as quench water in the SCWO process. However, on the basis of the information provided to it, the committee has significant reservations about the WRS functioning as planned. These reservations fall into three main areas: