小型锅炉烟气喷雾分离法脱硫的试验研究

以4t燃煤锅炉为对象，重点研究了喷雾分离法脱硫技术的工艺流程和主要设备，并给出了相应的试验结果。结果表明以清水为吸收剂，液气比≤0．1L／m^3，脱硫效率达到了60％—70％。本装置具有工艺简单、占地省、投资少、运行费用低的优点，特别适合用于中小型锅炉的改造。     

烟气脱硫技术的应用研究

概述了国内外烟气脱硫技术的应用现状，脱硫原理及其特点，并提出了我国烟气脱硫技术的研究开发方向。     

锅炉烟气脱硫除尘一体化装置的开发与应用

本文介绍了国内外已应用的锅炉脱硫除尘一体化装置,并结合国情,提出了应重点发展的锅炉烟气脱硫除尘一体化装置。     

烟气脱硫技术的应用研究

概述了国内外烟气脱硫技术的应用现状、脱硫原理及其特点 ,并提出了我国烟气脱硫技术的研究开发方向     

中国燃煤锅炉烟气脱硫技术的发展前景

本文在综述我国燃煤中小型锅炉和电站锅炉烟气脱硫技术现状的基础上，分析了我国燃煤锅炉烟气脱硫技术的发展前景．分析结果指出：我国中小型燃煤锅炉烟气脱硫技术近期是以完善湿法脱硫技术为主，远期将大力发展干法脱硫技术；在电站锅炉烟气脱硫方面，规模较小的电站锅炉将以喷雾干燥法为主要发展方向，大型电站锅炉近期仍以湿式石灰石－石膏法为主，远期将大力发展电子束辐照氨法脱硫脱硝技术。     

锅炉烟气脱硫除尘一体化装置的开发与应用

本文介绍了国内外已应用的锅炉脱硫除尘一体化装置,并结合国情,提出了应重点发展的锅炉烟气脱硫除尘一体化装置.     

锅炉烟气脱硫除尘一体化装置的开发与应用

本文介绍了国内外已应用的锅炉脱硫除尘一体化装置,并结合国情,提出了应重点发展的锅炉烟气脱硫除尘一体化装置.     

湿式等离子体烟气脱硫试验研究

介绍了湿式等离子体烟气脱硫试验，研究了模拟烟气参数、反应器结构和放电特性等因素对脱硫效率的影响，实验表明，试验结果为工业性应用提供了基本资料。     

超重力法锅炉烟气同时除尘脱硫脱硝

锅炉燃烧过程中产生的粉尘、SO2和NOx会对环境和人类造成严重的危害。随着人们环保意识的加强,锅炉烟气净化要求日趋严苛。进行了以O3为氧化剂,NaOH溶液为吸收剂,使用超重力反应器对锅炉尾气进行同时除尘脱硫脱硝的侧线实验研究,考察了不同操作条件对粉尘、SO2和NOx脱除率的影响规律,确定了适宜的操作条件：超重力反应器转速为1 000 r·min-1,气液比为125,pH值为11,O3/NOx物质的量之比为1.1。在该条件下,粉尘脱除率可达98.3%,SO2脱除率为98.4%,NOx脱除率为68.7%,处理后烟气能达标排放。超重力除尘脱硫脱硝一体化技术具有成本低、效率高、设备小和投资少等优点,在中小锅炉烟气净化过程具有广泛的应用前景。     

Use of Seawater in Flue Gas Desulfurization

For seasite power plants using seawater for condenser cooling, Bechtel developed a new process to remove better than 90 percent of flue gas SO₂ using seawater and lime. Tests demonstrate that marine life is not affected by the effluent from this unique scrubbing process; therefore, the aqueous effluent containing reacted products (gypsum) in solution at low concentration is suitable for discharge to the sea.     

Modeling of Dry Injection Flue Gas Desulfurization

Dry processes for controlling sulfur dioxide emissions by injecting sodium based sorbents in the ductwork ahead of a bag filter are effective and more simple alternatives to conventional FGD processes. This paper presents a fundamental kinetic model of the dry injection process. Experimental data from pilot scale tests are reported. The model is shown to be applicable to the dry injection process. However, further experimental work is recommended to get a better understanding of the reaction mechanisms.     

喷射鼓泡法烟气脱硫工艺

对以喷射鼓泡反应器为主设备，石灰石浆液为脱硫剂的湿法烟气脱硫工艺进行了实验研究，结果表明主要参数[烟气压降Δp、ф（液气）比、吸收液pH值、进气SO2浓度]对脱硫效率均有较大的影响。     

Sulfur Gas Emissions From Stored Flue Gas Desulfurization Sludges

The emissions of volatile sulfur-containing compounds from 13 flue gas desulfurization (FGD) sludge field storage sites have been characterized. Sulfur gas emissions from the sludge surfaces were determined by measuring the sulfur gas enhancement of sulfur-free sweep air passing through a dynamic emission flux chamber placed over selected sampling sites. Samples of the enclosure sweep air were cryogenically concentrated in surface-deactivated Pyrex “U” traps. Analyses were conducted by wall-coated, open-tubular, capillary column, cyrogenic gas chromatography using a sulfur-selective, flame photometric detector. Several major variables associated with FGD sludge production processes were examined in relation to the measured range and variations in sulfur fluxes including: (a) the sulfur dioxide scrubbing reagent used, (b) sludge sulfite oxidation, (c) “unfixed” or “fixed” FGD sludge, and (d) ponding or landfill storage. The composition and concentration of the measured sulfur gas emissions were found to vary with the type of sludge, the effectiveness of rainwater drainage from the landfill surface, the method of impoundment, and the sulfate/sulfite ratio of the sludge. Hydrogen sulfide, carbonyl sulfide, dimethyl sulfide, carbon disulfide, and dimethyl disulfide were identified in varying concentrations and ratios in the FGD sludge emissions. In addition, up to four unidentified organo- sulfur compounds were found in the emissions from four FGD sludges. The sulfur flux from one FGD storage pond was analyzed by gas chromatography-single ion monitoring mass spectrometry. In addition to the four identified sulfur compounds, this flux contained large concentrations of benzene, toluene, and α-pinene. The measured, total sulfur emissions ranged from less than 0.01 to nearly 0.3 kg of sulfur per day for an equivalent 100 acre (40.5 hectare) sludge impoundment surface.     

Resource Recovery from Flue Gas Desulfurization Systems

The cost effective benefits of yielding a flue gas desulfurization (FGD) sludge predominantly composed of CaSO₄·2H₂O, have been previously established. The recovery of this material as FGD by-product gypsum has been demonstrated abroad. Recently U.S. wallboard manufacturers have recognized the viability of this recovery practice. Such techno-economic decision making variables as a) by-product specification, b) transportation costs, and c) location of suitable FGD systems enable the recognition of FGD by-product recovery. Recent investigations of resultant solids content and chloride washing reflect the technical possibility of delivering a suitable product. Commercial and economic factors favor recovery based upon rising disposal and transportation costs. Existing and near term proposed systems surface the technical and commercial problems faced by utilities considering recovery.

Generation of an oxidized FGD sludge consisting of 90⁺% CaSO₄·2H₂O and dewatered to 80⁺% solids is technically achievable by air sparging within the FGD system. Although the product is suitable for land disposal, electric power utilities should consider and evaluate by-product recovery. U.S. wallboard manufacturers have established technical criteria for FGD by-product gypsum. Percent CaSO₄·2H₂O, final solids content, particle size, and chloride content are primarily technical parameters. Technology exists within the FGD industry to satisfy these criteria and results are discussed.

Economic factors comparing mining costs, transportation costs, and disposal costs are developed for specific utility projects. Such comparison established generalized financial criteria for a given utility to develop the economic reasonableness of considering FGD byproduct recovery.

End product user perspectives are presented providing electric utilities with a realistic appreciation for by-product recovery potential. Location of existing wallboard plants highlight potential recovery regions. Quality control problems are discussed in terms of generating a by-product rather than a disposable material.     

Sulfur Gas Emissions from Flue Gas Desulfurization Sludge Ponds

This paper presents initial measurement data on the emission of volatile, reduced sulfur-containing gases from flue gas desulfurization (FGD) storage ponds. Several different types of FGD stored sludges were studied including lime, limestone, and mixtures of fly ash and lime or limestone residues, some of which had been chemically stabilized. The volatile sulfur gas emissions were cryogenically concentrated and determined by wall-coated, open-tubular capillary column gas chromatography using a flame photometric detector. Hydrogen sulfide, carbonyl sulfide, dimethyl sulfide, carbon disulfide, and an unusual, unidentified sulfur-containing compound were found in the gaseous pond flux. Benzene, toluene, and α-pinene were also identified by gas chromatography-single ion monitoring mass spectrometry. The total reduced sulfur gas emission from a 100 acre pond approximated 2.0 kg day^?1 (as sulfur).     

Flue Gas Desulfurization: The State of the Art

ABSTRACT

Coal-fired electricity-generating plants may use SO₂ scrubbers to meet the requirements of Phase II of the Acid Rain SO₂ Reduction Program. Additionally, the use of scrubbers can result in reduction of Hg and other emissions from combustion sources. It is timely, therefore, to examine the current status of SO₂ scrubbing technologies. This paper presents a comprehensive review of the state of the art in flue gas desulfurization (FGD) technologies for coal-fired boilers.

Data on worldwide FGD applications reveal that wet FGD technologies, and specifically wet limestone FGD, have been predominantly selected over other FGD technologies. However, lime spray drying (LSD) is being used at the majority of the plants employing dry FGD technologies. Additional review of the U.S. FGD technology applications that began operation in 1991 through 1995 reveals that FGD processes of choice recently in the United States have been wet limestone FGD, magnesium-enhanced lime (MEL), and LSD. Further, of the wet limestone processes, limestone forced oxidation (LSFO) has been used most often in recent applications.

The SO₂ removal performance of scrubbers has been reviewed. Data reflect that most wet limestone and LSD installations appear to be capable of ~90% SO₂ removal. Advanced, state-of-the-art wet scrubbers can provide SO₂ removal in excess of 95%.

Costs associated with state-of-the-art applications of LSFO, MEL, and LSD technologies have been analyzed with appropriate cost models. Analyses indicate that the capital cost of an LSD system is lower than those of same capacity LSFO and MEL systems, reflective of the relatively less complex hardware used in LSD. Analyses also reflect that, based on total annualized cost and SO₂ removal requirements: (1) plants up to ~250 MW_e in size and firing low- to medium-sulfur coals (i.e., coals with a sulfur content of 2% or lower) may use LSD; and (2) plants larger than 250 MW_e and firing medium- to high-sulfur coals (i.e., coals with a sulfur content of 2% or higher) may use either LSFO or MEL.     

Status and Problems of Regenerable Flue Gas Desulfurization Processes

Fourteen sulfur and/or sulfuric acid producing regenerate FGD processes were discussed at the 1974 FGD Symposium in Atlanta. During the period elapsed since then, considerable status change has occurred on many of these regenerable processes. Other regenerable processes which were not as well known during 1974 have surfaced in 1975. The problems of obtaining reducing gases (hydrogen sulfide, carbon monoxide, and hydrogen) for the reduction of sulfur dioxide product streams to elemental sulfur have become severe due to shortages of natural gas or other petroleum based feedstock. A new sulfur producing process which employs CO and H₂ directly (rather than the H₂S required for liquid and vapor base Claus reactions) is gaining attention. This paper discusses briefly: (1) the announced status of the many regenerable FGD processes, (2) the problem of reductant gas supply, and (3) the effect on FGD processes of using coal based reducing gas instead of reformed natural gas.     

A History Of Flue Gas Desulfurization Systems Since 1850

Methods for removing sulfur dioxide (SO2) from boiler and furnace exhaust gases have been studied throughout the twentieth century. Early concepts useful for flue gas desulfurization (FGD) appear to have germinated in England circa 1850. The research during this period was motivated primarily by the quest to uncover the fundamental physical properties of substances.