Phycoremediation is the use of algae for the removal or biotransformation of pollutants from wastewater. Employing this technology in the treatment of industrial effluents presents an alternative to the current practice of using conventional methods, including physical and chemical methods. In the present study, the effluent from a leather-processing chemical manufacturing facility, situated at Ranipet, Tamil Nadu, India, was treated using the microalga, Chlorella vulgaris, which was isolated from the effluent itself. The objective of this study was to treat the effluent as well as ETP (effluent treatment plant) solid waste by phycoremediation (pilot-scale field study as well as laboratory study) and to analyse the physico-chemical parameters before and after treatment. The results obtained showed that Chlorella vulgaris exhibited appreciable nutrient scavenging properties under both laboratory and field conditions, although phycoremediation carried out in sunlight (field study) gave better results. Moreover, the growth of Chlorella vulgaris was faster under field conditions.

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Using algae to treat industrial effluents containing heavy metals presents an alternative to the current practice of using other biosorbents and physical and chemical methods. In this study, effluent from a leather-processing chemical industry in Ranipet, Tamil Nadu, India, was treated for the removal of heavy metals using the microalga, Chlorella vulgaris, which was isolated from the effluent itself. The objectives of this study were to (1) assess the mass balance of a model parameter, lead, in laboratory conditions and estimate the lead adsorption capabilities of the microalga and (2) conduct pilot-scale studies for the removal of heavy metals, using the microalga, from the effluent and the solid waste accumulated over the years generated by conventional treatment methods. The results of the study show that after 8 hours, Chlorella vulgaris exhibited a better adsorption capacity under sunlight compared to laboratory conditions (i.e., 30.6 mg/g dry weight vs 10.5 mg/g dry weight, respectively). Similarly, reduction of heavy metals and mass balance in pilot-scale field studies conducted in a high-rate algal pond showed that the microalga, apart from adsorption, complexation, and entrapment mechanisms, is likely to possess phycovolatilization capability probably via biotransformation processes. Water Environ. Res., 83, 291 (2011).

Industry experience indicates the vast majority of well failures in SAGD wells occur in the liner, and most of these appear to be related to a loss of subcool control. This paper presents an example of how two factors, well trajectory and reservoir performance, can combine to produce problems with subcool control that are difficult to discern under normal operation and likely to lead to a steam breakthrough event. Simulation of steam trap conformance is an important tool for optimizing SAGD efficiency, but it can also be instrumental for diagnosing, avoiding, and resolving subcool control issues. To be effective, the simulator must account for the parameters that govern conformance, which include reservoir performance, well geometry, reservoir properties, completion details, and operational controls. This example employs a rigorous simulation basis that captures the contributions of both injection well hydraulics and production well hydraulics to steam trap conformance, or the lack thereof. The example demonstrates how enhanced monitoring systems and procedures can be used to diagnose subcool control problems before a failure results. Furthermore, various mitigation strategies are explored to alleviate the subcool control problem and facilitate more efficient SAGD operation. The mitigation strategies include changes to the initial well design, such as customized injector or producer liners. The simulation basis enables the mitigation strategies to be assessed based on the uniformity and stability of the liquid level above the production well. The simulation results reveal different levels of effectiveness between the various mitigation options. This paper provides new insight into how factors like well trajectory and reservoir performance can compromise subcool control and explores creative solutions for improving SAGD performance.