This paper presents the findings of a comprehensive evaluation for a Primary Mineral Processing (PMP) company that contracted Battelle to identify economical technology to remove sulfate ion (SO 4 2-) from mineral slurry transport (MST) water, now disposed of as a waste, for reuse or sale. MST water is separated from product by dewatering a sulfidic mineral concentrate slurry prior to loading and shipping of the solid product. The MST water sulfate ion concentration is between 400 and 1720 mg/L, below the high concentrations for which technologies such as lime precipitation, crystallization, and evaporation are favorable, and above low concentrations that are amenable to ion exchange technology, reuse, or release. In addition, the salt concentrations fluctuate significantly causing processing issues with a number of purification technologies. The technical target is to reduce sulfate levels to < 500 mg/L SO 4 2-to allow water reuse, and especially to < 250 mg/L SO 4 2-(drinking water requirements) to provide the broadest reuse options. Based on company criteria of proven technology, operability, minimum residuals, and cost effectiveness in meeting the requirements for sulfate reduction, the two top-rated technologies recommended were ettringite production and precipitation using aluminum oxide, and electrochemical salt splitting.
Metals treatment and recovery from plating wastewater is important to protect the environment and to provide cost-effective alternatives to waste disposal. Battelle has developed alternative processes, using liquid-liquid extraction (LLX), to specifically remove metals from wastewaters. This paper presents demonstration results for anion liquid ion exchange (A-LIX TM ) and introduces cation liquid-liquid extraction (C-LLX). These technologies allow the recovery of the extracted metals, thus avoiding costly disposal and the attendant potential liability associated with disposal. Economic assessments, operational factors, and comparisons to conventional technology are presented.
Battelle's Hydroflex™ liquid-liquid extraction technology has been demonstrated for the remediation of metal and sulfate laden acid mine/acid rock drainage waters, removing sulfate to below 250 mg/L. In addition to the processed mine water, the process also produces a concentrated metal sulfate liquid byproduct and a concentrated sodium sulfate liquid byproduct. These byproducts have potential for use in the softening of flowback and produced waters in the Marcellus and Utica shale plays prior to reuse in hydraulic fracturing. This paper reports on Phase 1 of a Department of Energy project, which is preliminary qualification and design work for the full scale demonstration of a 378 liter per minute (100 gallon per minute) HydroFlex TM system to process Acid Mine/Acid Rock Drainage (AMD/ARD) water for use by the Oil and Gas industry. Initial range finding tests indicate that sulfate can be reduced to below 50 milligrams per liter (mg/L) in a single extraction stage, but that non carbonate hardness in the AMD/ARD makes the extraction process sensitive to over-mixing with organic entrainment within the processed water. Optimization of mixing and other extraction conditions in batch and continuous testing will be done to ensure production of water meeting the requirements of the oil and gas industry, as provided by industry and regulatory stakeholders.
Nutrient (nitrogen and phosphorus) concentrations in wastewater effluents can create significant ecological problems. This paper presents the results of using liquid-liquid extraction (LLX) technology for the removal of phosphorus (P) and/or nitrate (NO 3 ) from wastewater and recovery of concentrated, usable products instead of solutions or precipitates requiring disposal. Phosphates (ortho-(o-P) and poly-P) and nitrite/nitrate are recovered in a concentrated aqueous solution as sodium or potassium salts. This "PN-LLX" (for phosphorus and nitrogen removal/recovery) process is applicable to a wide variety of wastewaters, including municipal, industrial, or agricultural aerobically or anaerobically processed liquids or solids. Examples of applications include anaerobically digester supernatant filtrate/centrate; aerobic or anaerobic lagoon clarified effluent; animal feeding operations barn flush water; biologically industrial wastes, e.g. food wastes; industrial wastes with high phosphate or nitrate, e.g. phosphorus mining/phosphoric acid production, nitrations production, etc. Applicability to a wide variety of feed concentrations with achievement of low target final water-phase concentrations have been demonstrated in laboratory LLX screening tests. This paper will illustrate the LLX process as applied to a surrogate water containing o-P and NO 3 , and to animal (dairy) manure anaerobic digester effluent, and is called AD-LLX.
The U.S. Department of Defense (DOD) has engaged in destroying the U.S. stockpile of chemical weapons under the convention that was signed on January 13, 1993 on the prohibition of development, production, stockpiling and use of chemical weapons, and on their destruction of chemical weapons. The Pueblo Chemical Agent-Destruction Pilot Plant (PCAPP) is designed and constructed to destroy chemical agents by hydrolysis at a chemical munitions disposal facility of the DOD in Pueblo, Colorado. The State of Colorado encourages recycling water and minimizing water usage to the extent practicable because of the water shortage in southern Colorado. The permitted capacity of the wells supplying the PCAPP water system is 218,800 gallons per day (gpd). Water usage above this level must be provided by additional sources. PCAPP water usage in summer is estimated to be approximately 60,000 gpd. PCAPP design uses Veolia Water evaporation and crystallization technologies to recover water from the biotreated effluent. More than 80% of the recovered water is used to dilute the hydrolysate for biotreatment. Approximately 103 gpm (148,000 gpd) biotreated effluent is evaporated to recover water for reuse at the site. PCAPP permit requires that the recovered water quality from the BRS is acceptable for use as an effective substitute for well water at the site. Therefore, the recovered water is processed through granular activated carbon (GAC) adsorption units to comply with the Maximum Concentration Levels (MCLs) listed in the National Primary Drinking Water Standards. This paper presents results from evaporation/crystallization, dewatering, and carbon adsorption tests to confirm performance to meet the design parameters. Material selection for high chloride content (4,000-5,000 mg/L), foaming resulting from biosolids, and organics removal from offgas were some of the design challenges.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.