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Working at the food-energy-water nexus, we identified an abundant agricultural waste with little intrinsic value – banana stalk – that can be converted to biofuels and a template for water treatment materials via hydrothermal carbonization.

Nusselt number correlations are the defacto method for estimating heat transport rates in membrane distillation (MD) models. Accurate selection and application of Nusselt number correlations, however, is complicated by a large number of available correlations, uncertainty in the correlation accuracy across module dimensions, and the fundamental mass and heat transport incongruities introduced by applying correlations developed for heat exchangers to analyze MD processes. This work analyzes the accuracy of 23 Nusselt number correlations for empty and spacer-filled channels in experimental MD systems and tests the validity of classical heuristics for their selection. The accuracy is assessed by applying the Nusselt number correlations in an MD process model to estimate the permeate flux or membrane permeability values. These values are compared to the experimentally measured permeate flux and membrane permeability in empty channels (N = 240) and spacer-filled channels (N = 80). Our results demonstrate that the best Nusselt number correlation for empty channels had an average flux error of 29 ± 32% and an average permeability error of 71 ± 161%, with accuracy being a strong function of module size. The best correlation for spacer-filled channels had an average flux error of 9 ± 11% and an average permeability error of 6 ± 8%. These findings emphasize the sensitivity of MD models to estimates of heat transfer.

This study provides a review of the acoustic and ocean bottom sediment data collected during the Shelf Break Primer experiment conducted in 1996. The location of the experiment was in the southern New England Continental Shelf called the “New England Mud Patch.” The mud patch is a 13,000 square kilometer area covered by fine-grained sediment. Previous surveys in this area have estimated the thickness of this fine grained sediment deposit to be as much as 13 m. This layer of sediment rests on a reflector that is geomorphically similar to and continuous with the Holocene transgressive sand sheet, which is exposed on the shelf to the west of this area. This fine-grained sediment layer, which is oriented in an east-west direction seaward of the 55–65 m isobath, contains more than 30% silt and clay. During the Primer experiment, broadband acoustic sources were deployed in the western side of the “mud patch” along and across the continental shelf. The acoustic data collected on a vertical line array will be analyzed. Sediment data from gravity cores from the area will also be presented. [Work sponsored by Office of Naval Research, code 322 OA.]