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Reciprocating biofilters known as ReCip is a viable technology to manage nutrients, mainly nitrogen, problems at livestock operations such as swine farms and dairies. Past studies have demonstrated that ReCip is more adept at total nitrogen (TN) removal than traditional subsurface flow wetland systems. The traditional substrate used to attach biomass was rock aggregate; this media may be hard to obtain for some agricultural projects, so alternate substrates are tested and compared with the rock aggregate. The purpose of the study was twofold: first, different biofilm media were tested and compared in terms of treatment performance and, second, the long-term performance of a ReCip in continuous operation for 3 years was characterized. Four, 2.67 square meter ReCip systems with different treatment media – rock aggregate, recycled concrete aggregate (RCA), vertical-flow plastic media, and walnut shells – were operated at a 2-day THRT over the course of a 16 week study. The TN removal efficiencies for rock aggregate, RCA, plastic media, and walnut shell media were 43%, 53%, 25%, and 69% respectively. Surface based mass TN removal rates for the same media were 103, 128, 172, and 276 kg/ha-d respectively. A 134.2 square meter ReCip with rock aggregate media was running concurrently with the smaller ReCip systems. This ReCip was constructed ant operated since January 2010. TN removal efficiency and mass removal rate were 44% and 105 kg/ha-day. These values were close to results from the smaller rock media system.

In order to increase the current efficiency in copper electrowinning tankhouses, iron can be removed from the electrolyte using ion exchange. While this is a proven technology, very little data is available for the application of this technology to copper electrowinning electrolytes containing antimony and bismuth. The feasibility of utilizing iron ion exchange for the removal of iron from copper electrowinning electrolytes containing antimony and bismuth was studied in the laboratory. Apicolylamine, a sulphonated diphosphonic, an aminophosphonic and three sulphonated monophosphonic resins were tested. The picolylamine resin was found to be completely impractical as it loaded high levels of copper. All the phosphonic resins tested loaded an appreciable amount of antimony, however, only the aminophosponic resin loaded an appreciable amount of bismuth. Tests to determine whether or not the sulphonated monophosphonic Purolite S957 resin would continue to load antimony with time and, hence, reduce the resin's ability to remove iron gave inconclusive results. In the event that the resin's ability to remove iron is hampered due to antimony loading, testing has shown that the resin performance may be restored via a regeneration with a solution containing sulphuric acid and sodium chloride. A case study for the application of this technology to the CVRD Inco CRED plant has shown that, while iron removal by ion exchange is technically feasible, it will upset the plant's acid balance in electrolyte. Therefore, an acid removal process would need to be implemented in tandem with an iron ion exchange system. Additionally, preliminary calculations suggest that a system with a single ion exchange column may have difficulty removing sufficient iron for the CRED design conditions. Therefore, consideration should be given to the possibility of utilizing a two column system (one column loading, one column stripping).

Arsenic is ubiquitous whether it is naturally occurring or produced by humans. It is found at sites on the National Priority List and at sites operated by DOE, where it is the second most commonly found contaminant. More wastes containing arsenic will be produced due to the lowering of the Maximum Contaminant Level (MCL) for arsenic in drinking water which will result in more treatment facilities for arsenic removal that will generate residuals. Furthermore, arsenic can be released from such wastes under the reduced conditions that are found in landfills. Pyrite (FeS2) is believed to be a compound that has a high affinity for arsenic and is stable under anoxic conditions. The first task of this research was to develop a method for making pyrite crystals of defined size with minimal reaction time and at high yield. Effects on the synthesis of pyrite particles of pH, the ratio of Fe/S, temperature and reaction time were investigated in batch reactor systems. Pyrite was synthesized within 24 hours at pH values ranging from pH 3.6 through pH 5.6, and at a ratio of Fe/S of 0.5. X-ray diffraction and scanning electron microscopy were used to size and characterize the pyrite particles. Experimental and analytical procedures developed for this work, included a hydride generation atomic absorption spectrometry method for measuring arsenic species (As(III), As(V)). The synthesized pyrite was applied to remove arsenic and its maximum capacity for arsenic removal was measured in batch adsorption experiments to be 3.23 μmol/g for As(III) and 113 μmol/g for As(V). Information obtained on the characteristics of chemical species before and after the reaction with arsenic showed that iron and sulfur were oxidized. Last, how strongly arsenic was bound to pyrite was investigated and it was determined that release of arsenic from As(III)-pyrite is not affected by pH, but release from As(V)-pyrite is affected by pH with minimum release in the range pH 5 to pH 8.

Five commercial metal oxide nanoparticles (CuO, SiO2, Fe2O3, TiO2 and Al2O3) have been individually screened for mercury removal in a batch reactor under bicarbonate buffered and non-buffered aqueous solutions (DI water). Copper oxide was then selected for surface modification to enhance mercury removal. The surfaces of both laboratory prepared and commercially available copper oxide nanoparticles were treated with 1-octanethiol to produce copper sulfide and/or copper alkanethiol nanoparticles. The resulting particles were characterized using X-Ray Fluorescence(XRF), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The novel nanoparticles demonstrated very high mercury removal (> 99%) from both the buffered and non-buffered aqueous solutions.

Constructed wetlands (CWs) utilize the natural mechanisms in wetlands to remove pollutants by physical, chemical and biological processes. CWs are one of the ecological engineering methods to purity water quality and has been experimented to assess their capabilities to remove nutrients from eutrophic water bodies of lakes and reserviors. This study was carried out to compare the removal of nutrients between vegetated and unvegetated CWs. The vertical flow bed was placed in the upstream, while the horizontal subsurface flow bed was set in the downstream. Cannaceae was selected to plant in the vegetated CWs. Two kinds of hydraulic retention time (HRT), 3 days and 7 days, were applied and compared with each other in this study. The experimental results show that no significantly difference between vegetated and unvegetated systems. The removal efficiencies of SS, BOD, NH3-N, TP are measure equal to about 80%, 75%, 80% and 65%, respectively, while the removal efficiencies of TN, OP, and COD were reached about 50% and larger. Both of the two systems show high efficiencies for nutrient removal. In the comparison between the two kinds of HRT¡¦s, the HRT controlled at 3 days presented higher removal efficiencies than that controlled at 7 days.

Thesis (M.A.)--Marshall University, 2008. / Title from document title page. Includes abstract. Document formatted into pages: contains 145 p. Includes bibliographical references p.145.

Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains vi, 53 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 28-35).