某纸厂碱回收炉的改造及优化运行

介绍江西某纸厂碱回收炉的改造情况,并总结了碱回收炉的运行实践经验。改造后,纸厂废黑液的重复利用能力明显增强,碱回收率达80%以上,生产蒸汽达到环保、节能、增效三收益目的。     

75t/h掺烧亚铵黑液循环流化床锅炉技术分析

介绍了利用循环流化床锅炉燃烧技术处理亚铵法制浆所带来的黑液污染问题的可行性分析及其应用价值,对我国造纸行业的制污技术具有一定的推广应用价值.     

75t/h掺烧亚铵黑液循环流化床锅炉技术分析

介绍了利用循环流化床锅炉燃烧技术处理亚铵法制浆所带来的黑液污染问题的可行性分析及其应用价值,对我国造纸行业的制污技术具有一定的推广应用价值.     

75t/h掺烧亚铵黑液循环流化床锅炉技术分析

介绍了利用循环流化床锅炉燃烧技术处理亚铵法制浆所带来的黑液污染问题的可行性分析及其应用价值,对我国造纸行业的制污技术具有一定的推广应用价值。     

从工业排放气中回收氢气的技术经济分析

<正> 随着工业技术的发展,对工业气体(如氢、氧、氮和氨等)的需求日益增加。在当今世界自然资源不断减少,能源紧张和燃料价格上涨的情况下,扩大制取工业气体的来源和开发新的制造技术已成为当务之急。另一方面,化工、石油和冶金等工业部门生     

厌氧技术处理生活污水及其效果分析

厌氧生活污水分散处理技术具有投资少、能耗低、运行费用小和处理效率高等优点，已成为分散处理城镇生活污水的主要技术，应用前景十分广阔；文章分析和讨论了该技术的原理、设计、工艺和运行效果，结果表明，出水能够达到国家二级排放标准。     

节电技术经济效益计算与评价方法

本标准代替GB／T13471--1992《节电措施经济效益计算与评价方法》。 本标准与GB／T13471--1992相比,主要变化如下：     

探析啤酒工业废水处理技术的研究进展

在阐述啤酒废水的来源及特点的基础上,时几种常见的处理利用技术进行比较,得出单一处理技术不能从根本上解决啤酒废水的污染问题,只有将多种技术结合使用.才能达到经济效益和环境效益的统一.     

节能技术评价指标体系研究与应用

技术节能是节能工作的重要手段。节能技术应用也普遍存在推广难、选择难、融资难、落地实施难等问题。目前在节能技术推广工作中存在着缺乏统一的节能技术评价指标和评价标准等问题。本文研究构建了节能技术评价的指标体系,为先进实用节能技术的遴选、评估和技术分类推广提供评价基础。     

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.     

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.     

造纸废液污染及其治理技术

介绍了造纸工业废水污染的现状及各种制浆方法的主要污染物。重点介绍了碱法制浆黑液、中段水和抄纸废水三部分的治理方法     

Hydrogen production from supercritical water gasification of alkaline wheat straw pulping black liquor in continuous flow system

Supercritical water gasification of alkaline black liquor was investigated in a continuous flow system. The experiments were carried out at 400–600 °C, 25 MPa, with residence times ranging from 4.94 to 13.71 s. The results showed that the increase of temperature and residence time and the decrease of feeding concentration enhanced the gasification. The gaseous product contained high level of hydrogen (40.26–61.02%). Maximum COD removal efficiency (88.69%) was obtained at 600 °C. The alkalis in black liquor were found to be precipitated in the reactor during the gasification, which decreased the pH of the effluent to the neutral region (6.4–8.0). The precipitated alkalis were dissolved in the water when the fluid temperature in the reactor was cooled to about 360 °C which increased the pH of the effluent to 11.0. A simplified kinetic study for COD removal efficiency was done by the pseudo-first order reaction assumption. The apparent activated energy was 74.38 kJ/mol and the apparent pre-exponential factor was 10^4.05 s⁻¹.     

规模化猪场废水厌氧处理工艺及现存问题分析

分析论述了我国目前禽畜养殖业废水处理概况和规模化猪场废水的特征及其危害性,对应用于猪场废水处理的厌氧工艺的技术特点进行了分析对比;提出厌氧处理工艺中亟待解决的后处理问题和建议。     

Comparison of options for utilization of a potential steam surplus at kraft pulp mills—Economic performance and CO2 emissions

This paper compares different energy‐related investment options that can be implemented in a kraft pulp mill with a potential steam surplus. The options investigated include lignin extraction, electricity production, capturing of CO₂ and black liquor gasification with production of electricity or biofuels, here DME. The investment options are compared with respect to annual net profit and global CO₂ emissions for different future energy market scenarios. A further analysis of how different parameters such as policy instruments and investment costs affect the different technologies also is included. The results show that, generally, for reasonable levels of biofuel support, the best economic performance among the studied technologies is achieved by extraction of lignin valued as oil. However, if the level of support for biofuels is high, black liquor gasification with DME production generally has the best economic performance among the studied options. All the investment options investigated decrease global CO₂ emissions significantly. Capturing and storing CO₂ from the recovery boiler flue gases result in the highest CO₂ emissions reduction and also is an economically attractive option in scenarios with a high CO₂ emissions charge. Copyright © 2012 John Wiley & Sons, Ltd.     

Logistics cost analysis of rice straw pellets for feasible production capacity and spatial scale in heat utilization systems: A case study in Nanporo town,Hokkaido, Japan

Rice straw is a promising renewable energy source because it is abundantly available in Asia. This study conducted a case study of logistics cost analysis for rice straw pellets by considering all stages in the supply chain to define the main factors affecting the selling price of rice straw pellets: collection (job-commission or employment of part-time workers), transportation, storage (vinyl greenhouses or storage buildings with larger capacity), pelletizing, and delivery to users with biomass boilers. The selling price was found to be strongly dependent on the production capacity because the investment cost for the pellet production facility had a significant effect of economies of scale. A production capacity of larger than 1500 t y⁻¹ is required for rice straw pellets to compete with wood pellets and fossil fuels in the studied Japanese context if the subsidy rate for the investment is 50%, part-time workers conduct the collection, and rice straw is stored in the storage buildings. Our sensitivity analysis also showed an economically feasible spatial scale: for example, rice straw should be collected within a 20 km radius and the users should be within a 38 km radius when the production capacity is 1500 t y⁻¹. In addition, other critical factors related to the collection of rice straw from the paddy fields and transportation of rice straw rolls to storage were identified as planning factors to further reduce the total logistics cost of rice straw pellets.     

Energy and cost evaluation in total treatment system of sewage and waste

This paper discusses a total treatment system which is designed not only to treat waste and sewage discharged in a new town but also to use energy which is recovered from these waste materials as effectively as possible. Various alternative systems are planned by taking realization possibilities of new technologies and environmental impact into consideration, and their energy efficiencies and economy are investigated comprehensively. From the investigation, the following system is selected as the optimal one: In the sewage treatment system, an activation method using an ultradeep aeration tank is adopted as the aeration method, a method using hypochlorite as that for disinfection, and an anaerobic digestion system as that for sludge treatment. In the waste disposal system, a combined heat and power system with a pyrolysis furnace of rotary kiln type is adopted. In this total treatment system, the waste disposal system uses both the recovered gas and residues of sludge after methane fermentation in the sewage treatment process, and the sewage treatment process gets both steam and electricity which are generated by using the pyrolysis gas obtained in the pyrolysis furnace. As a result, it was made clear that the proposed total treatment system makes it possible not only to be operated by steam and electricity produced within the system itself, but also to transmit surplus power to the outside of the system.     

Development of energy efficiency principal component analysis model for factor extraction and efficiency evaluation in large‐scale chemical processes

In a large‐scale chemical plant, it is important to evaluate the energy efficiency (EE) of production to improve the production process and make production decisions. Essentially, finding the relationship model is the foundation of EE evaluation. Given the requirements of universality and practicability, the data‐driven model is widely used to describe the variable relationships. However, the variables stored in the data bank may be redundant, and some variables contain disturbances in the large‐scale chemical process, increasing the complexity of the model establishment. In this paper, a new EE factor extraction and EE evaluation method based on principal component analysis (PCA) (EEPCA) is proposed to enhance the accuracy of the EE values. By three stages (noise term estimation, model establishment, and model variable selection) in EEPCA, the accurate relationship models of utilized energy mediums and chemical products are established. On the basis of the built models, the EE of the chemical processes is evaluated and inferred. The effectiveness and practicality of the proposed method are demonstrated via a simulated process and a practical ethylene production.     

Energy policy in the Caribbean green economy context and the Institutional Analysis and Design (IAD) framework as a proposed tool for its development

Market integration efforts of Caribbean small island developing states have become transposed on the growing paradigm shift towards green economy pathways. Central to this is the challenge of implementing Caribbean energy policy in a manner that is aligned with green economy ideals and face the realities of regional indebtedness and environmental impacts. Here we analyze the current state of the Caribbean energy policy development arena and propose that the currently weak policy and institutional design regime might potentially benefit from the application of the Institutional Analysis and Design (IAD) model especially within the operational context of the green economy. It allows us to identify current policy dilemmas, bottlenecks and discrepancies and to disentangle some of them while offering up a way forward with others. We do not so much offer distinct recommendations but focus more on delineating how to clear the pathway for sound policy intervention and outcomes. By doing so we set forth a challenging agenda for future policy analysis research that will advance Caribbean energy policy in more robust ways.