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This paper presents results from the United Nations Environment Programme (UNEP)-coordinated project, “Reducing Mercury Emissions from Coal Combustion in the Energy Sector”, implemented in the Russ...

This paper introduces two new tools to quickly identify and assess a broad range of Hg emissions controls for utility gas cleaning systems worldwide. The Process Optimization Guidance (POG) document summarizes the available options for mercury control at most coal-fired power plants, covering everything from efficiency improvements and fuel switching through co-benefit effects (maximizing Hg capture in existing pollution control systems) to Hg-specific sorbent and oxidation technologies. The POG includes a “decision tree” concept that helps the reader determine the potential compliance strategies for particular coal-fired gas cleaning systems. The Interactive Process Optimization Guidance (iPOG) is a user-friendly software package that formalizes the “decision tree” concept in the POG document. It accurately estimates Hg removals and emissions rates for broad ranges of coal quality, the most common configurations for furnace firing and flue gas cleaning, and Hg controls, both inherent and external. Two ca...

The United Nations Environment Programme (UNEP) partnership area “Mercury releases from coal combustion” (The UNEP Coal Partnership) has initiated demonstrations of mercury air emission reduction at two coal-fired power plants in Russia. The first project has modified the wet particulate matter (PM) scrubber installed in Toliatti thermal plant to allow for addition of chemical reagents (oxidants) into the closedloop liquid spray system. The addition of oxidant resulted in significant improvement of mercury capture from 20% total mercury removal (without the additive) up to 60% removal (with the additive). It demonstrates the effectiveness of sorbent injection technologies in conjunction with an electrostatic precipitator (ESP). ESPs are installed at 60%, while wet PM scrubbers are installed at 30% of total coal-fired capacity in Russia. Thus, the two UNEP Coal Partnership projects address the majority of PM emission control configurations occurring in Russia.

The UNEP coal combustion partnership area has been established to contribute to significantly reduce global mercury emissions mainly though existing multi-pollutant reduction approaches. As part of this, the partnership area has been assisting participating governments in developing mercury inventories and providing technically sound information on cost effective approaches for enhancing reductions of mercury emissions. Guidance material has been produced for developing nations and countries with economies in transition. Activities are ongoing in China, India, Russia and South Africa, and new projects are being planned in Southeast Asia.

Twenty-one strains comprising Campylobacter laridis (nine), nalidixic acid sensitive campylobacters (NASC) (four), and urease-positive thermophilic campylobacters (UPTC) (eight) were characterized by one-dimensional SDS-PAGE of cellular proteins. The UPTC and NASC strains included six from river water, two from mussels and four from sea water. The type strains of three other Campylobacter species were included for reference. The protein patterns, which contained 45-50 discrete bands, were highly reproducible and were used as the basis for two numerical analyses. In the first, which included all the protein bands, the 21 strains formed nine clusters at the 80% similarity (S) level. The typical C. laridis strains were restricted to two phenons (2 and 5); the atypical strains being distributed among the remaining phenons. In the second analysis, which excluded the principal protein bands (40-48.5 kD range), the 21 strains formed five clusters at the 80% S level. The typical C. laridis strains were relatively homogeneous and fell into a single phenon (2) within which two subgroups were discernable. The atypical strains were more heterogeneous with respect to background protein pattern, with representatives appearing in all five phenons. An electropherotyping scheme comprising six electropherotypes, and based on both analyses is proposed. The high within-group S level and separation from reference strains of Campylobacter in the second analysis, suggested that UPTC and NASC strains belonged within C. laridis possibly as biovars.