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Cram, J. C. (1996). Diversion well treatment of acid water, Lick Creek, Tioga County, PA. Ph.D. thesis, Pennsylvania State University at University Park,, University Park.
Abstract: Diversion wells implement a fluidized bed of limestone for the treatment of acid water resulting from acid mine drainage or acid precipitation. This study was undertaken to better understand the operation of diversion wells and to define the physical and chemical factors having the greatest impact on the neutralization performance of the system. The study site was located near Lick Creek, a tributary stream of Babb Creek, near the Village of Arnot in Tioga County, Pennsylvania. Investigative methods included collection and analysis of site water quality and limestone data and field study of this as well as other diversion well sites. Analysis of data led to these general conclusions: The site received surface water influenced by three primary sources 1) precipitation, 2) mine drainage baseflow, and 3) melted snow. Water mostly influenced by precipitation events and mine drainage baseflow was more acidic than water influenced by melting snow conditions. The diversion wells were generally able to treat only half or less of the total stream flow of Lick Creek and under extremely high flow conditions the treatment provided was minimal. A range of flow conditions were identified which produced the best performance for the two diversion wells. Treatment produced by the system decreased through the loading cycle and increases to a maximum value after each weekly refilling of limestone. Fine grained sediment in the stream was found to be limestone of the same general composition as the material placed within the wells. Neutralization of acid water was largely due to microscopic particles rather than the limestone sediment discharged to the stream. Additional downstream buffering due to the limestone sediment physically discharged from the vessels was not apparent. Diversion well systems are inexpensive and simple to construct. In addition, the systems were found to be highly reliable and able to effectively treat acid water resulting from mine drainage and acid precipitation. Diversion wells provide better treatment when the treatment site is located at the source of the acidity (such as a mine discharge), rather than at the receiving stream. Systems should be designed with 15 to 20 feet of hydraulic head and the site must have year-round access. Diversion well systems require weekly addition of limestone gravel to the vessels to facilitate continual treatment. A great deal of commitment is necessary to maintain a diversion well system for long periods of time. These systems are more economical and require less attention that conventional chemical treatment of acid water. However, these systems require more attention that traditional passive treatment methods for treatment of acid, including mine drainage.
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Burnett, M., Skousen, J. G., Skousen, J. G., & Ziemkiewicz, P. F. (1996). Injection of limestone into underground mines for AMD control. In Acid mine drainage control and treatment. Morgantown: West Virginia University and the National Mine Land Reclamation Center.
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Gazea, B., Adam, K., & Kontopoulos, A. (1996). A review of passive systems for the treatment of acid mine drainage. Minerals Engineering, 9(1), 23–42.
Abstract: This review presents the current state of development of the passive mine water treatment technologies. The background of passive treatment is reviewed and the chemical and biological processes involved in metals removal and acidity neutralisation are detailed. The types of currently existing passive treatment technologies and their applicability range as defined by the mine water chemistry are presented. Finally, the performance of passive systems constructed for the treatment of acid mine drainage from both coal and sulphide metal mines is summarised.
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Juby, G. J. G. (1996). Desalination of calcium sulphate scaling mine water: Design and operation of the SPARRO process. Water Sa, 22(2), 161–172.
Abstract: The South African mining industry discharges relatively small quantities of mine service water to the environment, but these effluents contribute substantially to the salt load of the receiving waters. The poor quality of service water also has significant cost implications on the mining operations. Of the two main types of mine service water encountered in the gold mining industry, the so-called calcium sulphate scaling types is found in the majority of cases. Preliminary testwork on this type of water using membrane desalination processes revealed that only the seeded reverse osmosis type of process showed promise. To overcome certain process problems and high operating costs with this system, a novel membrane desalination technique incorporating seeded technology, called the SPARRO (slurry precipitation and recycle reverse osmosis) process, was developed. The novel features of the new process included; a lower linear slurry velocity in the membrane tubes, a lower seed slurry concentration, a dual pumping arrangement to a tapered membrane stack, a smaller reactor and a modified seed crystal and brine blow-down system. Evaluation of the SPARRO process and its novel features, over a five-year period, confirmed its technical viability for desalinating calcium sulphate-scaling mine water. The electrical power consumption of the process was approximately half that of previous designs, significantly improving its efficiency. Membrane performance was evaluated and was generally unsatisfactory with both fouling and hydrolysis dominating at times, although operating conditions for the membranes were not always ideal. The precise cause(s) for the membrane degradation was not established, but a mechanism for fouling (based upon the presence of turbidity in the mine water) and a hypothesis fora possible cause of hydrolysis (alluding to the presence of radionuclides in the mine water) were proposed. Product water from the SPARRO process has an estimated gross unit cost (including capital costs) of 383 c/m(3) (1994).
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Gong, Z., Huang, J., & Jiang, H. (1996). Study of comprehensive retrieval utilization and the treatment of acid mine wastewater. Zhongnan Gongye Daxue Xuebao = Journal of Central South University of Technology, 27(4), 432–435.
Abstract: Impact of precipitating on removing harmful metal ion in the acid mine wastewater with pH neutralizer and sulfide was studied. The possible way of retrieving heavy metal ion in wastewater was probed. The techniques for lime carbonate to reject iron for hydrogen sulfide to precipitate copper and for zinc-lime cream neutralization flocculation to treat, mine acid wastewater were chosen. The final water quality may reach national effluent standard; the copper content was 32% in the sulfide slag.
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