Reduce Sulfur Dioxide Emissions Research Articles

A Review of Markets for Clean Air: The U.S. Acid Rain Program by A. Denny Ellerman, Paul L. Joskow, Richard Schmalensee, Juan-Pablo Montero, and Elizabeth M. Bailey

Markets for Clean Air is the definitive text on the U.S. acid rain program. This innovative program uses a cap-and-trade approach, rather than the traditional command-and-control approach, to reduce sulfur dioxide emissions. The authors conclude that the program was successful in cutting the costs of SO2 emission reductions by about half, saving tens of billions of dollars. Both scholars and policy makers will have a better sense of the virtues and pitfalls of market-based regulation after reading this.

Integrated assessment of sulphur dioxide reduction schemes: Robustness studies, choice of environmental targets and country roles

The integrated assessment model, Abatement Strategies Assessment Model (ASAM) is described and applied to the reduction of sulphur dioxide emissions in order to ameliorate European acidification in a cost-effective manner. The use of critical loads to map the spatial variation of environmental sensitivity is a key factor underpinning this approach. Since these critical loads are not in practice attainable, intermediate target loads are required. ASAM is used in this paper to show that the use of the ‘gap-closure’ approach, to define target loads, and in particular the 60% gap-closure target used as a basis for the Oslo protocol, is particularly appropriate. The unique feature of ASAM it its step-wise approach to optimisation which allows examination of an abatement strategy aiming at a particular environmental target at any required overall European expenditure level, even if the target is not attained at this point. This is key to ASAM’s ability to compare the cost-effectiveness of strategies based upon different target-loads. Similarly, ASAM has been used to demonstrate the influence of the use of current reduction plans as a starting point for optimisation in countries which plan substantial emissions reductions. ASAM is also used to show that abatement strategies are robust to large uncertainties in abatement cost estimates in individual countries. Finally, the role played by individual countries in a typical model strategy is investigated by comparing the ecosystem areas brought under protection by expenditure in each country. This work was undertaken in the context of the United Nations Economic Commission for Europe’s (UNECE) preparations for a second sulphur protocol.

Marginal PM25: Nonlinear Aerosol Mass Response to Sulfate Reductions in the Eastern United States

ABSTRACT Reductions in airborne sulfate concentration may cause inorganic fine particulate matter (PM25) to respond nonlinearly, as nitric acid gas may transfer to the aerosol phase. Where this occurs, reductions in sulfur dioxide (SO2) emissions will be much less effective than expected at reducing PM2.5. As a measure of the efficacy of reductions in sulfate concentration on PM , we define marginal PM2.5 as the local change in PM2.5 resulting from a small change in sulfate concentration. Using seasonal-average conditions and assuming thermodynamic equilibrium, we find that the conditions for PM2.5 to respond nonlinearly to sulfate reductions are common in the eastern United States in winter, occurring at half of the sites considered, and uncommon in summer, due primarily to the influence of temperature. Accounting for diurnal and intraseasonal variability, we find that seasonal-average conditions provide a reasonable indicator of the time-averaged PM2.5 response. These results indicate that reductions in sulfate concentration may be up to 50% less effective at reducing the annual-average PM2.5 than if the role of nitric acid is neglected. Further, large reductions in sulfate will also cause an increase in aerosol nitrate in many regions that are the most acidic.

Effects of changes in the UK energy demand and environmental legislation on atmospheric pollution by sulphur dioxide

Ninety-nine percent of the sulphur dioxide generated over the period 1970 to 1994 arose from the combustion of fossil fuels in the energy sector. The annual mass emission of sulphur dioxide has fallen by 58% over this period, due to the reductions in outputs from coal and petroleum fired plants. The influence of natural-gas power generation has played an important part in this reduction. Four major pieces of environmental legislation have been enacted to control sulphur-dioxide emissions: the Control of Pollution Act 1974, and three EEC Directives are discussed. The UK emissions in 1994 were 49% below the 1980 baseline and 9% ahead of the 1998 EU target level. The protocol on the reduction of sulphur-dioxide emissions, adopted in 1985, required a cut in the total SO 2 emissions of 30% by 1993, based on 1980 levels. The UK achieved a reduction of 37% by the end of 1993. Sulphur-dioxide emissions are predicted to fall according to the six scenarios in Energy paper 65 as a reference case. The predicted decline is in line with the UNECE targets set for 2010.

98/02414 Desulfurization of stack gases from coal power stations and progress in sulfur dioxide emission reduction in Czech Republic : Kraitr, M. and Sirotek, V. Chem. Inz. Ekol., 1997, 4, (4), 471–480. (In Polish)

98/02414 Desulfurization of stack gases from coal power stations and progress in sulfur dioxide emission reduction in Czech Republic : Kraitr, M. and Sirotek, V. Chem. Inz. Ekol., 1997, 4, (4), 471–480. (In Polish)

Multi-pollutant modelling and the critical loads approach for nitrogen

Understanding of the processes driving the deposition of acidic sulphur, oxidised- and reduced-nitrogen species has improved dramatically over recent years. A simple trajectory model approach is used here to describe the highly coupled behaviour of sulphur dioxide (SO 2), oxides of nitrogen (NO x ) and ammonia (NH 3). The model is able to reproduce the salient features of the geographical distribution of the main wet-deposited pollutants across the United Kingdom. A feature of the model is the important role played by the oxidation products of sulphur dioxide and nitrogen oxides in determining the distribution of wet-deposited ammonium. Scenarios employing substantial reductions in European sulphur dioxide emissions (based on the 1994 UN-ECE Sulphur Protocol) also produce concomitant reductions in wet-ammonium deposition. This behaviour serves to emphasise the importance of establishing multi-pollutant strategies within the European application of the critical loads approach to nitrogen.

Improving Efficiency in Bilateral Emission Trading

When environmental damages from emissions are spatially nonuniform, permit trading has been modeled most often as a “pollution offset program” in which emission permits are traded between agents, subject to constraints on ambient air quality. To date the institution envisioned to implement such a program involves trading on a bilateral and sequential basis. However, simulation studies indicate that the sequence of trades may alter the outcome and undermine the cost savings from a pollution offset program. This paper identifies a design for the trading institution that tends to overcome this phenomenon and improve the efficiency of equilibria obtained in a simulation model. We model a bilateral trading process for the reduction of sulfur dioxide emissions with a stochastic description of the sequence of trades within groups of nations in Europe. When trading takes place between disaggregated, stylistic representations of economic enterprises, rather than between national governments, a significantly greater portion of potential savings is achieved. In fact, under most sets of assumptions, approximate first order stochastic dominance is achieved wherein the more decentralized the trading agents, the greater the expected savings from a trading program.

STABILIZING CATTLE FEEDLOT SOIL WITH FLUIDIZED BED COMBUSTOR ASH

Many cattle feedlots are operated on bare soil because it is expensive to cover the entire lot with concrete. During heavy rainfalls, feedlots built on clay-rich soils often become muddy as their soils lose strength. These soils cannot support the weight of animals or equipment. As a result, the animals’ rate of gain suffers, and feedlot management becomes difficult. Fluidized Bed Combustor (FBC) ash from the Iowa State University Physical Plant was used to produce a significant increase in soil strength on a cattle feedlot near Nevada, Iowa. FBC ash is the residue from burning high-sulfur coal in fluidized bed combustors. Limestone (calcium carbonate) enters the combustor with the coal as a sorbent to reduce sulfur dioxide emissions. FBC ash is considered a “nuisance” waste, and the cost for disposal exceeds US$20 per metric ton.Stabilizing cattle feedlot soil with FBC ash represents a recovery of resources because the ash, when combined with clay soil and water, has cementious properties. Research was conducted with three objectives: (1) to determine whether FBC ash can be used to increase the strength of feedlot soil when applied at a level of quality control attainable by using ordinary agricultural tillage equipment; (2) to compare feedlot soil stabilized with FBC ash to non-stabilized feedlot soil in both laboratory and field tests; and (3) to develop a low-cost alternative to paving a feedlot with concrete. Field results from a feedlot treated with FBC ash show that soil strength was improved 200% to 300% when compared with an adjacent untreated feedlot.

96/06591 Design and operation of the coke-oven gas sulfur removal facility at Geneva steel

The coke-oven gas sulfur removal facility at Geneva Steel utilizes a combination of two technologies which had never been used together. These two technologies had proven effective separately and now in combination. However, it brought unique operational considerations which has never been considered previously. The front end of the facility is a Sulfiban process. This monoethanolamine (MEA) process effectively absorbs hydrogen sulfide and other acid gases from coke-oven gas. The final step in sulfur removal uses a Lo-Cat II. The Lo-Cat process absorbs and subsequently oxidizes H{sub 2}S to elemental sulfur. These two processes have been effective in reducing sulfur dioxide emissions from coke-oven gas by 95%. Since the end of the start-up and optimization phase, emission rate has stayed below the 104.5 lb/hr limit of equivalent SO{sub 2} (based on a 24-hr average). In Jan. 1995, the emission rate from the sulfur removal facility averaged 86.7 lb/hr with less than 20 lb/hr from the Econobator exhaust. The challenges yet to be met are decreasing the operating expenses of the sulfur removal facility, notably chemical costs, and minimizing the impact of the heating system on unit reliability.

The benefits of reduced damage to buildings from abatement of sulphur dioxide emissions

The 1994 Oslo Protocol for reduction of sulphur dioxide emissions was developed in the context of transboundary air pollution and its effects on acidification of natural ecosystems. However there are additional benefits of such emission abatement which are concentrated closer to the source in the country of origin. This paper dicussses the damage to buildings and materials which may be avoided as a result of the Oslo Protocol, and gives an approximate indication of the economic value of this saving.

The effect of limestone particle size on sulphur dioxide retention in a fluidized bed combustor

This paper reports on the effect of limestone particle size and operating parameters on the reduction of sulphur dioxide emissions in a fluidized bed combustor operating under unstaged combustion conditions. The experimental rig consisted of a stainless steel combustor, 2 m high and 0.3 m square in section. The experiments were carried out at overall fluidizing velocities between 1–2 m/s, bed temperature 830–880°C, 20–40% excess air level, bed particle size of 665 μm and limestone particle size between 0.8–3 mm mean diameter. An uncooled sampling probe located at the cyclone exit was used to determine sulphur dioxide. The results showed that the bed temperature had the most significant effect on sulphur dioxide retention. An increase in excess air level and decrease in limestone particle size resulted in an increase in sulphur dioxide reduction. Over 70% reduction could be achieved using coarse (1–2 mm) limestone under unstaged combustion conditions.

95/00644 Reduction of sulfur dioxide emissions from burning of briquets from central German lignite

95/00644 Reduction of sulfur dioxide emissions from burning of briquets from central German lignite

The effect of gas-phase chemistry on aqueous-phase sulfur dioxide oxidation rates

The rates and mechanisms of both gas and liquid phase reactions for the oxidation of sulfur dioxide play an important role in the production of atmospheric acids and aerosol particles. Rhodeet al. (1981) concluded that sulfate production rates were highly non-linear functions of sulfur dioxide emission rates. Their modelling study used an HO x termination mechanism for the HO—SO2 reaction in the gas-phase. Stockwell and Calvert (1983) determined that one of the products of the overall reaction of HO with sulfur dioxide was an HO2 radical. The National Research Council (1983) using a version of the Rhodeet al. (1981) model modified to include HO2 production from the HO—SO2 reaction concluded that sulfate production becomes much more linear with respect to reductions in sulfur dioxide emissions. However, the cause of this increased linearity was not explained by the National Research Council report. It is demonstrated that the increased linearity is due to the coupling of gas-phases and aqueous phase chemistry. The gas-phase sulfur dioxide oxidation mechanism has a very significant effect on hydrogen perodide production rates.

Preparation and Characterization of High Surface Area Al2O3-MgAl2O4 Solid Solutions

Mixed metal oxides with spinel-type structure are often used as model systems for catalytic studies, and some of them find current industrial usage. Magnesium aluminate, MgAl[sub 2]O[sub 4], acts as an efficient transfer catalyst for reducing sulfur dioxide emissions, and it can also be used as a convenient support for metal carbonyls and other catalyst precursor materials. For these applications, high surface area and accessible porosity are desirable properties. The classical method to prepare MgAl[sub 2]O[sub 4] involves high-temperature solid state reaction between MgO and Al[sub 2]O[sub 3], but severe sintering leads to very low surface areas. Suitable precursors have been sought to obtain a high surface area spinel. They include coprecipitated hydroxides or oxalates and [gamma]-alumina impregnated with a magnesium nitrate solution. Reported surface areas of MgAl[sub 2]O[sub 4] samples obtained from these precursors, after mild calcination at about 800 K, are in the 50-120 m[sup 2]g[sup [minus]1] range. The authors describe here the preparation and characterization of MgAl[sub 2]O[sub 4], and also Al[sub 2]O[sub 3]-MgAl[sub 2]O[sub 4] solid solutions, with surface areas of 250-300 m[sup 2]g[sup [minus]1]. Interest in the solid solutions stems from the fact that gradual changes of chemical composition provide a means to modulate surfacemore » acidity. 17 refs., 3 figs., 1 tab.« less

Electrical, control and instrumentation aspects of the Drax flue gas desulphurisation plant

During the past decade there has been increasing awareness of the problems of acid rain and the need to reduce sulphur dioxide emissions from power stations. The retrofitting of flue gas desulphurisation equipment to Drax power station is a major part of the emission reduction programme in the UK, and at £700 million is currently National Power's largest capital project. This article concentrates on three aspects of the project: electrical supplies, distributed control system and railway signalling.

The toxicity of selenium in experimental freshwater ponds.

Flue Gas Desulphurization equipment installed in coal-fired power stations to reduce sulphur dioxide emissions produces effluent containing several contaminants, including selenium. To assess the effects that this might have on fish reproduction and biological community richness, selenate and selenite were added to freshwater pond systems to achieve duplicated nominal concentrations of 0 (control), 2, 10 and 25 μg Se/L. Perch (Perca fluviatilis), grass carp (Ctenopharyngodon idella Val.) and stickleback (Gasterosteus aculeatus) were placed in each pond in the early summer and left relatively undisturbed until the following spring. A spawning tray was then placed in each pond and monitored regularly for the appearance of perch egg ropes. When ropes were found, they were removed to the laboratory and either placed in uncontaminated well water or exposed to selenium. Almost half the perch exposed to 25 μg Se/L died during the pond experiment, but there were no observed deaths at the lower concentrations. No grass carp were recovered from the 25 μg Se/L ponds but all were recovered from the other ponds. Stickleback were missing from all treatments, presumably due to predation by the perch. Perch egg ropes were found in seven of the eight ponds, and all but one rope showed signs of successful fertilisation. Hatching success in the laboratory was highly variable for eggs obtained from the 0, 2, and 10 μg Se/L ponds, but was always above zero. No eggs hatched from ropes obtained from the 25 μg Se/L ponds. Effects of selenium on plants, macroinvertebrates and zooplankton in the ponds were generally limited. Accumulation of selenium in fish was dose-related and comparable with results reported from other contaminated systems. The results from this experiment suggest that mean environmental concentrations of approximately 25 μg Se/L may seriously affect the reproductive capacity of perch, but no clear effects on reproduction are evident at mean concentrations of 10 μg Se/L and below. Selenium-induced effects occur during gametogenesis, but only become evident between fertilization and hatching.

S0 Emission Trading Rights: A Model for Other Pollutants

Beginning in 1995, electric utilities will have to reduce sulfur dioxide emissions under new rules that not only will revolutionize the regulation of sulfur dioxide but also provide a model to reduce a wide variety of other pollutants. Under authorization of the Clean Air Act of 1990, the Environmental Protection Agency will issue tradable emissions allowances to electric generating utilities. Actual emissions will have to match allowances EPA assigns to utilities, giving them a right to emit a predetermined amount of sulfur dioxide. Each allowance will be equivalent to the right to emit 1 ton of sulfur dioxide per year. The allowances will be based on utilities' average emissions in the reference years 1985 through 1987. EPA hopes thereby to harness the free enterprise system and reduce emissions of a major precursor to acid rain to 9 million tons annually—a 10 million ton reduction from 1980. The chemical process industry would do well to pay ...

Utility investment behavior and the emission trading market

The Clean Air Act Amendments of 1990 require electric utilities to reduce sulfur dioxide emissions and establishes a system of tradeable emission allowances to achieve this objective. This paper develops a model of utility investment decisionmaking that shows how regulatory rules will affect the utility's incentive to choose among different compliance strategies. The results of the model are extended to the overall market for emission allowances to show how the benefits from trading can be affected by regulatory rules. The analysis provides guidance for public utility regulation that will help achieve the social objective of minimizing the cost of pollution control.

Relevance of carbonate minerals in the processing of Australian Tertiary oil shales

The Tertiary oil shale deposits of eastern Queensland, Australia, comprise an important future source of alternative liquid fuels. Carbonate minerals are important in relation to selection of processing conditions and in limiting sulphur dioxide emissions. This paper characterizes such minerals from the Stuart, Rundle, Condor, Nagoorin, Nagoorin South, Duaringa, Yaamba and Lowmead deposits. Composite and stratigraphically selected samples were mineralogically analysed using chemical analyses, X-ray diffractometry, thermogravimetry and scanning electron microprobe analysis. Carbonate minerals significant in processing include calcite, magnesian calcite, siderite and magnesian, calcian and manganoan siderites which occur in different amounts in the various deposits. Dolomite and ferroan dolomite were sporadically observed. Calcite and magnesian calcite are decomposed in the combustor and reduce sulphur dioxide emissions by reaction to form CaSO 4 in the combusted solids. Siderite type minerals are fully or partially decomposed depending upon siderite type and process conditions in the retort. The iron oxides produced react with hydrogen sulphide in the retort gases. Calcium replacing iron in the siderite also reacts with sulphur dioxide to form CaSO 4 and hence limits sulphur dioxide emissions from the combustor.

U.S.-Canada sign pact to reduce acid rain

The U.S. and Canada have recently signed a transboundary air pollution agreement that puts to rest a key irritant in otherwise congenial relations: control of pollutants causing acid rain. Signed in Ottawa on March 13, the legally binding accord commits the U.S. to reducing its total sulfur dioxide emissions 10 million tons below 1980 levels by the year 2000. Sulfur dioxide emissions are to be capped permanently at 8.95 million tons per year for electric utilities by 2010. The seven easternmost Canadian provinces are pledged to reduce sulfur dioxide emissions to 2.3 million tons by 1994 and to cap emissions at that level from 1995 to 1999. By the year 2000, Canada will adopt a permanent emissions cap of 3.2 million tons of sulfur dioxide per year. Total annual U.S. emissions of nitrogen oxides are to be reduced about 2 million tons from 1980 levels by the year 2000. Canada is slated to adopt a ...