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The article reports on the computational fluid dynamics (CFD) method, a flow modeling tool used in analyzing and improving the duct design to reduce nitrogen oxide (NOx) emissions. CFD optimizes flue gas and ammonia flow patterns through the selective catalytic reduction (SCR) unit which enhances the design for NOx reduction applications. Moreover, the proper mixing of NH3 and NOx contributes to the effectiveness of SCR post-combustion technology.

The article focuses on the properties of formic acid in Methanol solutions and what implications this has in liquid chromatography coupled mass spectroscopy gradient elution analyses. It states that the acid content of dilute formic acid solutions in methanol declined with time. It mentions that the initial amount of water in the solutions influenced the extent of the formic acid decline. It examines the effect that the acidity change had on the separation of peptides.

The article offers information on the factors to consider when making decision on in-situ chemical oxidation (ISCO) and in-situ chemical reduction (ISCR). Factors to be dealt with when selecting between an ISCR or ISCO approach include targeted treatment area, contaminant characteristics, presence of free product and environmental impacts. It is mentioned that ISCR is compatible with an active biological dechlorinating environment and can be upgraded to the Distributed Computing Environment (DCE) stall. On the other hand, ISCO is more effective in a strongly oxidizing environment.

The article discusses the use of nanoscale zero-valent iron (ZVI) particles in controlling groundwater volatile organic compounds. Organic contaminants can be completely reduced to non-toxic compounds, such as ethene and ethane through the use of nanoscale ZVI particles. Nanoscale ZVI particles have proven to be more reactive and effective partially over granular, coarser iron particles because of their increased surface area. The reactivity of the nanoscale ZVI particles can be improved by depositing a small amount of a noble metal on the surface of iron, which creates bimetallic nanoscale particles. The results of the six pilot test of the dynamics of chlorinated compounds reduction are described.

This article presents information on anaerobic-anoxic-oxic technique for biological phosphorus removal. The effects of dissolved oxygen contents, NO⊃N and activated sludge age on the phosphorus removal of anaerobic-anoxic-oxic technology were recently put to the test at the No. 4 Wastewater Treatment Plant in Guilin, China. The anaerobic-anoxic-oxic biological nitrogen and phosphorus removal process synthesizes traditional processes of activated sludge, biological nitration, nitrate reduction and biological phosphorus removal. In this process, biological oxygen demand, suspended solids, and all forms of nitrogen and phosphorous are removed. Bacteria in the activated sludge of anaerobic-anoxic-oxic denitrification and dephosphoration consist mainly of nitro, denitro- and polyphosphorus bacteria. Ammonia nitrogen and organic nitrogen in an oxic state are converted by nitrobacteria to nitrates. In the anoxic stage, nitrates from reflux are converted to nitrogen gas by denitrification. Polyphosphorus bacteria in the anaerobic process always remove phosphorus and absorb degradable organic materials, such as inferior fatty acids. In the oxic stage, polyphosphorus bacteria absorb excessive phosphorus.

The article provides insights into enhanced bioremediation of explosives impacted soil in the United States. The key to bioremediation method is the use of sequential anaerobic and aerobic conditions, or treatment cycles, generated through the application of proprietary organic and inorganic amendments. The method enhances and promotes natural biodegradation rates by adjusting parameters in a soil or waste matrix to stimulate in situ chemical reduction of target compounds by indigenous microorganisms. Two case studies, the Iowa Army Ammunition Plant and the Yorktown naval weapons station, illustrating the implementation of the method are described.

Focuses on the options to reduce greenhouse gases with a clear understanding of the positive and negative aspects of each options. Development of the harm factory rating system that is claimed to allow normalization of risks among different pollutant forms; Projects for the removal of the carbon dioxide and other pollutants from the exhaust gases emitted by a pulverized coal-fired plant; Evaluation of the replacement of existing subcritical coal plants with new highly efficient plants utilizing the super critical design.

Reports on the fixed-bed hydrogenation unit manufactured by CXI for contract manufacture. Use of reduction reaction in synthesizing various products including pharmaceuticals, plastics, agricultural, specialty chemicals and intermediates; Flexibility of the technology in tying in distillation or any of three different reactors; Unique features of the unit; Availability of pilot facilities for scale-up.

Reports on the introduction of a nitrogen oxide reduction technology developed by Entropy Technology & Environmental Consultants in the U.S. Installation of the technology; Discussion on its chemical reduction process; Combination of systems for the creation of the technology.