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To implement sustainable water resource management, the industries that produce a huge amount of wastewater are aiming to recycle wastewater. Reverse osmosis (RO) is an advanced membrane process that can produce potable water from wastewater. However, the presence of diverse pollutants in the wastewater necessitates effective pretreatment to ensure successful RO implementation. This study evaluated the efficiency of microfiltration (MF) and ultrafiltration (UF) as two pretreatment methods prior to RO, i.e., MF-RO and UF-RO, for recycling poultry slaughterhouse wastewater (PSWW). The direct treatment of PSWW with RO (direct RO) was also considered for comparison. In this study, membrane technology serves as a post treatment for PSWW, which was conventionally treated at Sanderson Farm. The results demonstrated that all of the processes, including MF-RO, UF-RO, and direct RO treatment of PSWW, rejected 100% of total phosphorus (TP), over 91.2% of chemical oxygen demand (COD), and 87% of total solids (TSs). Total nitrogen (TN) levels were reduced to 5 mg/L for MF-RO, 4 mg/L for UF-RO, and 9 mg/L for direct RO. In addition, the pretreatment of PSWW with MF and UF increased RO flux from 46.8 L/m2 h to 51 L/m2 h, an increase of approximately 9%. The product water obtained after MF-RO, UF-RO, and direct RO meets the required potable water quality standards for recycling PSWW in the poultry industry. A cost analysis demonstrated that MF-RO was the most economical option among membrane processes, primarily due to MF operating at a lower pressure and having a high water recovery ratio. In contrast, the cost of using RO without MF and UF pretreatments was approximately 2.6 times higher because of cleaning and maintenance expenses related to fouling. This study concluded that MF-RO is a preferable option for recycling PSWW. This pretreatment method would significantly contribute to environmental sustainability by reusing well-treated PSWW for industrial poultry purposes while maintaining cost efficiency.
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This content will become publicly available on August 1, 2025
Elucidating the use of pressure-recovery diagrams for analyzing energy consumption in reverse osmosis desalination
The pressure-recovery (P-Y) diagram used in reverse osmosis (RO) literature to compare energy consumptions in different RO configurations has a flaw of not holding the design flux constant. In this work, the P-Y diagrams are constructed with the aid of transport models. It is shown that the area underneath the P-Y curve represents the specific energy consumption (SEC) imposed by design flux and thermodynamics, which may be reduced by improving spatial uniformity in flux. The trend generally observes the equipartition of entropy production theorem. For seawater RO (SWRO) in which pressure drop relative to feed osmotic pressure is small and operation is near the thermodynamic limit, staged designs with interstage booster pumps enable a more uniform flux, thus reducing the SEC. However, for low-salinity brackish water RO (BWRO), improving flux uniformity may lead to a higher SEC as the increased friction loss often outweighs the reduced energy requirement imposed by system flux.
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- Award ID(s):
- 2140946
- PAR ID:
- 10535749
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Desalination
- ISSN:
- 0011-9164
- Page Range / eLocation ID:
- 118033
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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