造纸厂废弃苇末热能利用的尝试

简介造纸厂废弃苇末的简易随炉燃烧处理方法。此法既处理了污染环境的大量苇末，又充分利用苇末热能产生蒸汽，具有投资小效益高的优点，供所有草浆造纸企业治理草末污染参考。     

我国环保产业发展的重点领域与技术

1.在水环境保护及污染治理方面,急需研究开发和完善一批实用的污染控制技术。如草浆造纸黑液的全套治理技术,高浓度难降解工业废水的治理技术,湖泊富营养化防治技术等; 2.在空气污染治理方面,要围绕烟尘和硫氧化物防治技术与设备开发,重点开发大型燃煤电站脱硫技术,天然气脱硫装置和中小型锅炉实用脱硫技术与设备,开发汽车机内净化和三元     

余杭区规模猪场污染治理模式分析

对杭州市余杭区规模猪场污染治理所采用的3种治理模式进行了分析，提出要根据猪场的规模、经济条件及地理环境，因地制宜地选择污染治理模式。达到既治理污染又发展生产，带动农业经济的可持续发展。     

污染治理设施绩效评价方法研究浅析

如何有效地监管污染治理设施,是保证治理设施正常运转的关键措施。因此,迫切需要一种对污染治理设施进行综合评价的方法,通过选用合适的绩效评价方法对治理设施进行综合评价。介绍污染治理设施绩效评价方法的确定原则及不同绩效评价方法的优缺点和适用范围。     

汾河水污染控制研究

实现汾河变清的目标,是山西经济可持续发展的保证,介绍了汾河水域的污染特征;分析了传统污染治理方式的缺陷,阐述了总量控制模式是治理汾河污染的有效途径,是提高汾河污染总量控制的技术政策。     

加快污染治理市场化与环境保护机制创新

阐述污染治理市场化的现状,推进污染治理市场化遇到的问题及环境保护机制创新,如何加快污染治理市场化进程.     

龙井湾污染指标浓度变化对地下水径流通道的分析

龙井湾泉水受上游化工厂生产污染,主要污染指标有P、氨氮、F和pH,在污染治理过程中,研究龙井湾地下水污染途径是污染治理的关键。通过地表调查、水质取样分析手段,研究龙井湾泉水流量和污染指标浓度之间的变化关系,锁定主要污染来源,确定污染径流通道,为龙井湾的泉水污染治理提供依据。     

考虑电能质量优化的模块化固态变压器及控制策略研究

配电网中的大量电力电子器件会产生谐波污染和电流三相不平衡,导致供电质量下降。文章首先分析了固态变压器输入级等效电路、不平衡故障以及谐波污染的原理,同时考虑序分量分离带来的延迟问题,提出了一种基于改进瞬时对称分量法的电流分序输入级控制策略,将该治理策略同固态变压器的传统方式相比较,实现了隔离电压三相不平衡故障与谐波污染,同时对网侧电流与直流电压中的倍频分量进行治理。最后,基于MATLAB/simulink平台建立系统仿真模型,验证了所提方案对不平衡故障与谐波治理的优越性。     

非道路用发动机尾气排放机外净化研究

本文论述了加强治理非道路用发动机尾气排放污染的重要性和迫切性,分析了治理非道路用发动机的尾气排放污染应采用的净化方法,并重点介绍了机外净化及其优点。在发动机试验台架上,选择了两种DOC型尾气净化器,进行了排放比对试验,验证了机外净化的效果。本文在最后总结了非道路用发动机尾气排放机外净化的特点。     

非道路用发动机尾气排放机外净化研究

本文论述了加强治理非道路用发动机尾气排放污染的重要性和迫切性,分析了治理非道路用发动机的尾气排放污染应采用的净化方法,并重点介绍了机外净化及其优点。在发动机试验台架上,选择了两种DOC型尾气净化器,进行了排放比对试验,验证了机外净化的效果。本文在最后总结了非道路用发动机尾气排放机外净化的特点。     

Chronoamperometric and chronopotentiometric investigation of Kraft black liquor

Black liquor is an effluent of pulp and paper mills. The electrolysis of Kraft black liquor is drawing high attention, as it leads to lignin recovery by anodic electrodeposition and cathodic production of hydrogen. However, the lignin oxidation process on black liquor is still poorly understood, requiring further fundamental studies to allow its comprehension. Therefore, detailed electrochemical studies are being carried out on the topic, which will allow a deeper insight in the involved electrode processes. The Kraft black liquor is physicochemically characterised, with the determined high values of pH, conductivity and lignin content (12.4, 460 mS cm^?1 and 48.8 g dm^?3, respectively) demonstrating the suitability of black liquor as an electrolyte medium. Voltammetry, chronoamperometry (CA) and chronopotentiometry (CP) techniques are done in black liquor solutions using Pt, Ni and AISI 304 SS electrodes to investigate the lignin oxidation process. The number of exchanged electrons is determined for each electrode material from CA and CP measurements using classic Cottrell and Sand analyses, respectively, with the faradic efficiency of Ni being close to that of Pt. The low-cost and high efficiency suggest Ni as a promising electrode material for application in black liquor electrolysers.     

纸浆黑液为催化剂的高变质无烟煤水蒸气催化气化的热重与在线质谱研究

以纸浆黑液为催化剂,用热天平的等温法研究高变质无烟煤常压纯水蒸气催化气化反应。通过热重曲线和在线质谱分析解释纸浆黑液催化气化机理;为扣除纸浆黑液中固形物对气化过程的影响,对纸浆黑液和以纸浆黑液为催化剂的无烟煤进行等温实验,通过在线质谱确定了升温段热解与恒温段气化的产物,并得出了消除纸浆黑液影响的煤转化率的计算公式。     

Catalytic effect of black liquor on the gasification reactivity of petroleum coke

CO₂ gasification of petroleum coke using black liquor as a catalyst was performed in a thermogravimetric analyzer (TGA) under temperatures 1223–1673 K at ambient pressure to evaluate the effect of black liquor loading on petroleum coke gasification. It was found that the gasification reactivity of petroleum coke was improved greatly by black liquor. The gasification reactivity was affected by different loading methods in the order: wet grinding > dry grinding > physical impregnation > dry mix. The catalytic activity of black liquor was higher than that of pure alkali metal. The effect of temperature on the gasification reactivity of petroleum coke was changed by black liquor. The reactivity reaches its maximum at 1573 K. The reactivity of petroleum coke was found higher than that of Shenfu coal when black liquor loading is 5 wt.% (of petroleum coke), clearly demonstrating that black liquor could be an effective catalyst for petroleum coke gasification.     

黑液燃烧研究进展

黑液———KP法制浆工艺的主要副产品,已成为美国和北欧最重要的工业燃料之一。尽管黑液在余热锅炉中的燃烧应用已有大半个世纪,但有关如何提高燃烧效率及其污染控制、排放的研究却是近年来才发展起来的。先粗略介绍了KP法制浆过程及黑液燃烧过程,简单回顾了近年来国外在黑液燃烧模型领域的研究进展,并就黑液与其它燃料的比较,分析其燃料特性。     

Waste to energy by industrially integrated supercritical water gasification - Effects of alkali salts in residual by-products from the pulp and paper industry

Supercritical water gasification (SCWG) is a method by which biomass can be converted into a hydrogen-rich gas product. Wet industrial waste streams, which contain both organic and inorganic material, are well suited for treatment by SCWG. In this study, the gasification of two streams of biomass resulting from the pulp and paper industry, black liquor and paper sludge, has been investigated. The purpose is to convert these to useful products, both gaseous and solids, which can be used either in the papermaking process or in external applications. Simple compounds, such as glucose, have been fully gasified in SCWG, but gasification of more complex compounds, such as biomass and waste, have not reached as high conversions. The investigated paper sludge was not easily gasified. Improving gasification results with catalysts is an option and the use of alkali salts for this purpose was studied. The relationship between alkali concentration, temperature, and gasification yields was studied with the addition of KOH, K₂CO₃, NaOH and black liquor to the paper sludge. Addition of black liquor to the paper sludge resulted in similarly enhancing effects as when the alkali salts were added, which made it possible to raise the dry matter content and gasification yield without expensive additives.     

Hydrothermal treatment of black liquor for energy and phenolic platform molecules recovery in a pulp mill

The aim of this study was to study the conversion of black liquor under hydrothermal conditions and its integration in a pulp mill. Three sulfur-free black liquors produced from caustic soda cooking of prehydrolyzed softwood, prehydrolyzed hardwood and non prehydrolyzed hardwood chips were converted. Experiments were performed in a batch reactor, for temperature between 250 °C and 310 °C, and for holding time between 5 and 120 min. Three phases were formed: an aqueous phase containing monomeric phenolic compounds and the sodium cations, a biocrude containing most of the carbon, and a small amount of gas. The combustion of the biocrude could allow an energy recovery for the mill of up to 70%. The main monomeric compounds identified in aqueous phase were phenol, catechol, guaiacol and syringol, with a total yield up to 28 g kg⁻¹ of dry BL, at 250 °C. Among them, guaiacol was the major product. Sodium recovery was 97 %, slightly better than typical kraft recovery value, and compatible with causticizing. Finally, results obtained with a kraft softwood lignin were compared to those obtained with softwood black liquor. Results show that biocrude yields were greater with black liquor, whereas platform molecules production was higher with lignin. Presence of carbohydrates derivatives in black liquor is identified as a major parameter for biocrude production as it would favor bonding between phenolic species.     

Comparison of pulp-mill-integrated hydrogen production from gasified black liquor with stand-alone production from gasified biomass

When gasified black liquor is used for hydrogen production, significant amounts of biomass must be imported. This paper compares two alternative options for producing hydrogen from biomass: (A) pulp-mill-integrated hydrogen production from gasified back liquor; and (B) stand-alone production of hydrogen from gasified biomass. The comparison assumes that the same amount of biomass that is imported in Alternative A is supplied to a stand-alone hydrogen production plant and that the gasified black liquor in Alternative B is used in a black liquor gasification combined cycle (BLGCC) CHP unit. The comparison is based upon equal amounts of black liquor fed to the gasifier, and identical steam and power requirements for the pulp mill. The two systems are compared on the basis of total CO₂ emission consequences, based upon different assumptions for the reference energy system that reflect different societal CO₂ emissions reduction target levels. Ambitions targets are expected to lead to a more CO₂–lean reference energy system, in which case hydrogen production from gasified black liquor (Alternative A) is best from a CO₂ emissions’ perspective, whereas with high CO₂ emissions associated with electricity production, hydrogen from gasified biomass and electricity from gasified black liquor (Alternative B) is preferable.     

Chemical process simulation for minimizing energy consumption in pulp mills

Chemical process simulation has proven to be an effective tool for performing a systematic and global analysis of energy systems to identify routes for maximizing the process efficiency concerning to the heat recovery. This paper shows an application of computer simulations in a Brazilian pulp mill, using two strategies for minimizing the mill energy consumption. In the first one, the overall heat transfer coefficient has been predicted for each body of the multiple effect evaporators by using continuous on-line data from the industrial plant in the black liquor recover unit. By monitoring oscillations of this heat transfer coefficient, the suitable time for washing the evaporator heat transfer surfaces can be well determined, reducing the energy loss during black liquor evaporation. In the second strategy, the liquor combustion has been simulated as function of the black liquor solids concentration to analyze its effect on the recovery boiler efficiency improvement.     

炭化气氛对黑液煤浆及不同煤种气化反应特性的影响

煤气化前阶段的炭化气氛(温度、时间)影响到煤焦的气化反应特性.采用不同的炭化温度和炭化时间制备了黑液水煤浆、普通水煤浆以及其他5种煤的焦样,得到了各种煤焦气化反应的碳转化率;同时,通过扫描电子显微镜分析手段鉴别焦炭表面孔隙分布情况.试验结果表明,相同炭化气氛下得到的7种不同煤焦中,黄陵煤焦的气化活性最高,说明煤化程度越高反应性越低;由于黑液中有机物和无机物钠盐的影响,黑液水煤浆焦的气化特性高于普通水煤浆焦和新汶煤焦.煤焦的气化反应性,不仅与煤阶有关,还和煤焦中含氧官能团和无机化合物的含量有关,同时煤浆中外在添加的无机物组分也影响到煤焦的气化活性.     

Evaluation of effect of evaporation on supercritical water gasification of black liquor by energy and exergy analysis

Supercritical water gasification (SCWG) is a promising innovative black liquor handling method. The low concentration of black liquor is a burden for the system scale and investment cost. In this study, we introduced black liquor evaporator to increase the concentration using self-generated steam and power, and studied its influence on the energy and exergy efficiency. The results showed that increasing black liquor concentration from 10 wt% to 20 wt% reduced the energy efficiency but increased the exergy efficiency of the system without evaporator. With the evaporator, an optimal target concentration existed for the exergy efficiency owing to the influence of the target concentration on the balance between the energy consumption and saving brought by the evaporator. With black liquor condensed from 15 wt% to 21.82 wt%, maximum exergy efficiency of the system (41.95%) was obtained. For lower-concentration black liquor, more water needs to be evaporated to get the optimal concentration and evaporator was more desired because it brought greater improvement on the exergy efficiency. The increasing effect number of multi-effect evaporator shifted the optimal concentration to higher values, which increased from 19.93 wt% to 23.13 wt% when the effect number increased from 4 to 7. The exergy efficiency of the system was also improved, and the improvement was more significant at higher target concentration.