我国燃煤电厂烟气脱硫技术与设备国产化进展、问题及建议

烟气脱硫是国际上广泛采用的控制二氧化硫的成熟技术，也是我国控制燃煤电厂二氧化硫排放的主要途径。近几年，国家有关部门组织实施了燃煤电厂烟气脱硫技术与设备国产化示范工程，开发研制了部分专用设备，燃煤电厂烟气脱硫技术与设备国产化取得了积极进展。     

湿法脱硫技术关键问题研究

针对我国烟气脱硫存在的实际问题,研究了湿法脱硫关键技术,如多孔板环面积、层数、安装角度、孔径及开孔率,喷淋塔压力降特性等。解决了湿法烟气脱硫过程中关键问题,实现了除雾器的国产化,优化了物料分配技术,降低了脱硫石膏含水率,形成了一整套具有自主知识产权的湿式高性能脱硫技术,并成功应用于多个燃煤电厂商用脱硫工程,取得了显著的经济效益和社会效益。     

《火电厂烟气脱硫关键技术与设备国产化规划要点》摘要

介绍国家贸易委员会印发的《火电力烟气脱硫关键技术与设备国产化规划要点》：火电厂ＳＯ２排放和控制状况，烟气脱硫工艺的选择，烟气脱硫国产化面临的形势及主要问题，烟气脱硫国产化目标和措施。     

烟气海水脱硫技术的研发与应用

简述了北京龙源环保工程有限公司依托863项目自主研发的大型燃煤电站烟气海水脱硫成套技术及其基本原理和工艺流程,详细介绍了该项目的研究内容、步骤,及其研发技术在示范工程中的应用。该技术的成功研发与应用对我国海滨燃煤锅炉烟气脱硫工艺和设备的国产化,降低投资和运行成本具有重要意义。     

OI2-WFGD-II烟气脱硫技术介绍

简要介绍了江苏苏源环保工程有限公司开发的OI2-WFGD-II湿法烟气脱硫技术的工艺特点、设备布置、技术参数、设备国产化以及技术应用.     

OI~2-WFGD-Ⅱ烟气脱硫技术介绍

简要介绍了江苏苏源环保工程有限公司开发的OI^2-WFGD-Ⅱ湿法烟气脱硫技术的工艺特点、设备布置、技术参数、设备国产化以及技术应用。     

太原第一热电厂简易湿法脱硫技术及经济分析

介绍中日使用太原第一热电厂简易湿法烟气脱硫（太－ＦＧＤ）的工艺、装置及运行状况,论述其特点和国产化问题,重点对建设和运行费用进行了分析,指出太－ＦＧＤ对我国火电厂脱硫,特别是建厂时没有预留脱硫场地的老厂改造具有应用前景。     

电子束烟气脱硫技术特点及适用条件分析

以某电厂为实例论述了电子束脱硫工艺的流程、特点和外部条件,并进行了电子束脱硫工艺的技术经济分析,提出了电子束脱硫工艺的适用条件以及国产化思路。     

燃煤电厂烟气脱硫有关问题的思考

就燃煤电厂烟气脱硫相关问题，如排污费的使用，工艺技术的选择，脱硫公司的资质，电价的核定，脱硫设备的国产化，管理的规范化等进行了讨论。     

石灰石-石膏湿法烟气脱硫废水的处置

综述了石灰石一石膏烟气脱硫废水的特点，对废水的来源、水量、性质和处理方法进行了论述，并重点分析了化学中和处理工艺，以便加快脱硫废水处理装置的国产化进程。同时还指出了脱硫废水处理中存在的问题及今后的研究方向。     

Review of the kinetics of alkaline degradation of cellulose in view of its relevance for safety assessment of radioactive waste repositories

The degradation of cellulose (a substantial component of low- and intermediate-level radioactive waste) under alkaline conditions occurs via two main processes: a peeling-off reaction and a basecatalyzed cleavage of glycosidic bonds (hydrolysis). Both processes show pseudo-first-order kinetics. At ambient temperature, the peeling-off process is the dominant degradation mechanism, resulting in the formation of mainly isosaccharinic acid. The degradation depends strongly on the degree of polymerization (DP) and on the number of reducing end groups present in cellulose. Beyond pH 12.5, the OH^- concentration has only a minor effect on the degradation rate. It was estimated that under repository conditions (alkaline environment, pH 13.3-12.5) about 10% of the cellulosic materials (average DP = 1000-2000) will degrade in the first stage (up to 10⁵ years) by the peeling-off reaction and will cause an ingrowth of isosaccharinic acid in the interstitial cement pore water. In the second stage (10⁵-10⁶ years), alkaline hydrolysis will control the further degradation of the cellulose. The potential role of microorganisms in the degradation of cellulose under alkaline conditions could not be evaluated. Proper assessment of the effect of cellulose degradation on the mobilization of radionuclides basically requires knowing the concentration of isosaccharinic acid in the pore water. This concentration, however, depends on several factors such as the stability of ISA under alkaline conditions, sorption of ISA on cement, formation of sparingly soluble ISA-salts, etc. A discussion of all the relevant processes involved, however, is far beyond the scope of the presented overview.     

Study of Aging Characteristics of Ternary Blends of Polyethylenes—II

Six film samples of low-density polypropylene (LDPE)/linear LDPE (LLDPE)/high-density polypropylene (HDPE) with varying ratios of LDPE (20–45 ... wt%) and LLDPE (25–50 wt%) having a fixed amount of HDPE at 30 wt% were prepared by blown film extrusion technique. The samples were aged at four different temperatures, 55°, 70°, 85°, and 100°C, for four different time periods in the interval of between 150 hours and up to 600 hours. The change in the structure of various constituents and the formation of various oxygenated (peroxy and hydroperoxy) and unsaturated groups during thermo-oxidative degradation was discussed by infrared spectroscopy. The visiosity-average molecular weight was found to have decreased slowly in the initial aging hours and temperatures, whereas it decreased by 10% with its previous value tensile strength that is, 100°C when aged for 600 hours. The tensile strength of the sample first increased by 67% at 55°C and 89% at 70°C up to 450 hours, whereas the values increased by 52.5% at 85°C and 33.9% at 100°C when aged for 150 hours and then decreased. The percentage elongation at break increased by 2.7% at 55°C and 10.7% at 70°C for 150 and 300 hours of aging, respectively, whereas the percentage decreased when aged at 85°C and 100°C for up to 600 hours of aging. The values of gel content (percent) increased and initial degradation temperature decreased with aging time and temperature.     

Determination of the Burning Characteristics of a Slick of Oil on Water

The burning rate of a slick of oil on a water bed is characterized by three distinct processes, ignition, flame spread and burning rate. Although all three processes are important, ignition and burning rate are critical. The former, because it defines the potential to burn and the latter because of the inherent possibility of boilover. Burning rate is calculated by a simple expression derived from a one-dimensional heat conduction equation. Heat feedback from the flame to the surface is assumed to be a constant fraction of the total energy released by the combustion reaction. The constant fraction (χ) is named the burning efficiency and represents an important tool in assessing the potential of in situ burning as a counter-measure to an oil spill. By matching the characteristic thermal penetration length scale for the fuel/water system and an equivalent single layer system, a combined thermal diffusivity can be calculated and used to obtain an analytical solution for the burning rate. Theoretical expressions were correlated with crude oil and heating oil, for a number of pool diameters and initial fuel layer thickness. Experiments were also conducted with emulsified and weathered crude oil. The simple analytical expression describes well the effects of pool diameter and initial fuel layer thickness permitting a better observation of the effects of weathering, emulsification and net heat feedback to the fuel surface. Experiments showed that only a small fraction of the heat released by the flame is retained by the fuel layer and water bed (of the order of 1%). Ignition has been studied to provide a tool that will serve to assess a fuels ease to ignite under conditions that are representative of oil spills. Two different techniques are used, piloted ignition when the fuel is exposed to a radiant heat flux and flash point as measured by the ASTM D56 Tag Closed Cup Test. Two different crude oils were used for these experiments, ANS and Cook Inlet. Crude oils were tested in their natural state and at different levels of weathering, showing that piloted ignition and flash point are strong functions of weathering level.     

Calculation of carbon balances for evaluation of the biodegradability of polymers

Establishing carbon balances has been proven to be an applicable and powerful tool in testing biodegradability of polymers. In controlled degradation tests at a 4-L scale with the model polymer poly(-hydroxybutyrate) (PHB), it was shown that the degree of degradation could not be determined with satisfactory accuracy from CO₂ release alone. Instead, the course of degradation was characterized by means of establishing carbon balances for the degradation of PHB withAcidovorax facilis and a mixed culture derived from compost. Different analytical methods for determining the different carbon fractions were adapted to the particular test conditions and compared. Quantitative determination of biomass and residual polymer were the main problems in establishing carbon balances. Amounts of biomass derived from protein measurements depend strongly on assumptions of the protein content of the biomass. Selective oxidation of biomass with hypochlorite was used as alternative, but here problems arose from insoluble metabolic products. Determination of soluble components with the method of chemical oxygen demand (COD) also includes empirical assumptions but seems acceptable if the dissolved carbon fraction is in the range of some 10% total carbon. Results confirm both analytical assays and theoretical approaches, in ending up at values very close to 100%, within an acceptable standard deviation range under test conditions comparable to standard test practice.Paper presented at the Bio/Environmentally Degradable Polymer Society—Third National Meeting, June 6–8, 1994, Boston, Massachusetts.     

Model of technological alternatives of production of sodium chromate (VI) with the use of chromic wastes

This article presents a mathematical model which describes the sodium chromate (VI) production process with the use of chromic waste as a substitution of natural raw materials. This model is a function of selected process parameters common for all of the examined alternatives and based on equations of material balance. Optimization of the elaborated technological alternatives of the production process with use of recycling of chromic waste has been evaluated by determining the extreme value of the quality indicator WJ. This indicator defines the quantity of waste created in the process. Optimization results enabled the selection of the optimal technological solution from all of the alternatives possible for use in industrial practice. Negative values of the indicator prove that there is the possibility of introducing to the process a larger quantity of waste than the one obtained in the process and transported to the storage heaps.     

鼓泡式反应器高径比对氨法烟气脱碳性能的影响

以N2和CO2混合气模拟燃烧烟气,研究了鼓泡反应器的高径比以及反应条件对氨法烟气脱碳性能的影响。实验结果表明:在相同高径比的条件下,CO2吸收率随氨水质量分数的增加、反应温度的升高而逐渐增大,随进气CO2体积分数和模拟烟气流量的增加而逐渐减小;CO2吸收率随高径比的增加而增大,在高径比为3.98、氨水质量分数为28%、进气CO2体积分数为10%、模拟烟气流量为1.0L/min、反应温度为40℃的条件下,CO2吸收率最高可达100%。     

化学品生物降解性的评价与预测

介绍了有机化学物质生物降解性的测定方法及其预测方法研究概况，并讨论了生物降解性评价的发展前景。     

Structure-biodegradation relationships of polymeric materials. 1. Effect of degree of oxidation on biodegradability of carbohydrate polymers

The biodegradability of oxidized starch and inulin has been studied in relation to the degree of periodate oxidation to dialdehyde derivatives, by measuring oxygen consumption and mineralization to carbon dioxide. A higher degree of oxidation of dialdehyde starch and dialdchyde inulin results in a lower rate at which the polymers are biodegraded. It is demonstrated that the biodegradation rate of dialdehyde inulin derivatives decreases more than that of equivalent starch derivatives. The differences in biodegradation behavior between dialdehyde starch and dialdehyde inulin, resulting from comparable modifications, are discussed in terms of conformational structure.     

Mechanism of Microbial Degradation of Slow-Release Fertilizers

Methyleneureas are condensation products of urea and formaldehyde of different molecular mass and solubility; they are used in large amounts both as resins, binders, and insulating materials for industrial applications, as well as a slow-release nitrogen fertilizer for greens, lawns, or in bioremediation processes. In the present study, the microbial breakdown of these products was investigated. The nitrogen was released as ammonia and urea, and the formaldehyde released immediately oxidized via formiate to carbon dioxide. The enzymatic mechanism of metabolization of methyleneureas was studied in microorganisms isolated from soil, which were able to use these compounds as the sole source of nitrogen for growth. A strain of the Gram-negative bacterium Ralstonia paucula (formerly Alcaligenes sp. CDC group IVc-2) completely degraded methylenediurea and dimethylenetriurea to urea, ammonia, formaldehyde, and carbon dioxide. The enzyme initiating this degradation (methylenediurease) was purified and turned out to be different from the previously described enzyme from Ochrobactrum anthropi with regard to its regulation of expression and physicobiochemical properties. Fungal degradation of methyleneureas may occur via the formation of organic acids, thus leading to a nonenzymatic degradation of methyleneureas, which are unstable under acidic conditions.     

Effect of Degree of Substitution of Octenyl Succinate Starch on Enzymatic Degradation

Octenyl succinate starch of degree of substitution (ds) 0.03, 0.07, and 0.11 was synthesized in an aqueous medium. These compounds were then tested for the susceptibility to enzymatic degradation. The multiple-enzyme regime of -amylase, amyloglucosidase, and pullulanase was chosen for the evaluation. This combination of enzymes had been proven to degrade 99.5% of unmodified starch to glucose and hence was chosen for this study. It was found that even small amounts of subsituent caused a considerable decrease in the extent of degradation. The net extent of degradation decreased with increasing ds. Surprisingly, the amount of glucose from all three substituted substrates was quite similar, suggesting the effect small amounts of subtituent had on the enzymatic activity.