Effective biomass integration into existing combustion plant

Fossil fuels such as coal still dominate in current energy production plants. However, due to their large carbon footprint caused by combustion, rising prices and the unclear an increased interest in renewable and alternative fuels is observable. By 2020, renewable energy should account for 20% of the EU’s final energy consumption in order to reduce the negative impacts of the utilization of fossil fuels. Biomass-based fuels contribute to this effort.The optimization approach introduced in this article supports sustainable and financially feasible biomass integration into the existing large energy producing system with combined heat and power (CHP) production. The objective is to identify optimal conditions (optimal amount of burned fuels with respect to energy demands and energy flows through key components) with regard to maximum annual financial profit.The general mathematical model of a CHP plant utilizing more types of fuels is introduced and an optimization problem is formulated. The approach application is demonstrated on a case study involving existing CHP plant co-firing coal and biomass. The optimization problem is implemented and solved in GAMS (General Algebraic Modeling System). A sensitivity analysis of crucial parameters is performed and the results are presented and discussed.     

垃圾焚烧电厂热电联产的经济性分析

合理利用垃圾资源进行热电联产,是节能减排、改善环境的有力措施.以某2×750 t·d-1垃圾焚烧电厂为例,通过模型研究发现热电联产可以减少垃圾焚烧电厂的冷源损失,提高全厂热效率;利用一抽蒸汽进行热电联产可实现蒸汽品质的梯级利用,获得较高的经济效益;供热量为30 t·h-1,垃圾热值由4185.9 kJ·kg-1增加至8...     

热电厂参与风电调峰的方法评述及展望

在中国“三北”地区冬季供暖期,大量热电联产机组因供暖而难以调峰是导致负荷低谷时段风电大量弃风的主要原因。提出了在中国“三北”地区电网中,热电厂通过解耦“以热定电”约束参与风电低谷调峰的设想,介绍了热电调峰可行方案的运行机理、技术特性和适用范围;展望了其在中国电力系统中的应用前景和巨大的经济效益;分别从电厂层面、电力系统层面和国家政策层面讨论了热电调峰这一领域的重点研究方向。     

基于有机朗肯循环的生物质能热电联产技术的研究

阐述了中国生物质能开发和利用的前景,总结比较了国内外不同的生物质能热电联产技术,提出并介绍了基于有机朗肯循环(ORC)的生物质能热电联产技术。最后,讨论了ORC在回收余热、废热和冷能等方面的应用。     

双碳目标下燃煤热电联产机组储能技术应用分析

目的  “碳达峰、碳中和”目标要求现有能源结构进行深刻变革。提高原有燃煤热电联产机组灵活调节能力是保障新能源电力安全并网的重要内容之一。 方法  分别从燃煤热电联产系统灵活调节需求、潜在储能应用现状以及耦合储能技术的发展方向等方面进行了评述。 结果  分析认为深度“热电解耦”仍是提高燃煤热电联产系统的关键内容。其次,为满足“源–荷”匹配性,储能技术将在燃煤热电联产系统中发挥重要作用,其中具有应用潜力的储能技术主要包括储热、蓄电以及飞轮储能。 结论  最后根据燃煤热电联产机组耦合储能技术的应用特点,提出了储能性能老化、新能源消纳、扩容区域热电负荷中长期变更、初投资与回收期的经济性分析四个方面的建议以及需要注意的相关问题。     

多种可再生能源渗透场景下的热电联产系统优化

针对传统热电联产(CHP)系统受热电耦合的限制,灵活调节能力低、可再生能源消纳能力弱的问题,分析了传统热电联产系统的灵活性不足机理,提出采用地热源热泵来提高其灵活性。为了确定地热源热泵(GSHP)的最优容量,建立了考虑切负荷惩罚、可再生能源弃用惩罚、设备投资成本及运行成本的热电联产-地热源热泵系统优化模型,将该模型运用到可再生能源渗透率(可再生能源发电量/总发电量)分别为15%,40%和55%的3种情景中。结果表明：地热源热泵的容量随可再生能源渗透率的提升而提升,同时地热源热泵的集成可以扩大系统的可运行域,提高可再生能源的消纳容量;在最优地热源热泵容量下,3种场景的日节约成本分别为38%,64%和70%,同时集成系统的能源利用率可超过100%,可再生能源弃用的惩罚成本分别下降100%,89%和89%。     

电力市场中热电联产机组两部制电价机制的研究

通过比较热电联产机组与常规火电机组的优势劣势,分析了国内外电力市场中热电联产机组的扶持政策和运营情况,提出了热电联产机组参与电力市场的两部制电价机制设计方法,给出了热电联产机组两部制电价中可用容量、可用小时数、容量电价、电量电价等参数的计算方法,形成了一套科学合理的价格形成机制,使其与常规火电机组可以参与同一电力市场竞价上网。     

小型天然气发动机热电联产装置的开发与可行性

简要介绍了气体燃料发动机驱动热电联产系统的结构组成,分析了国外在类似产品开发过程中所遵循的技术路线,在此基础上概要阐述了机组开发中需解决的关键问题。     

我国热电冷三联产存在问题分析

热、电、冷三联产实现了能源的梯级利用,不但可以达到节约能源的目的,而且可以减少温室气体的排放,实现环保效益。该技术在国内外得到了广泛的发展和应用。从技术、节能、经济性等角度剖析了阻碍我国热、电、冷发展的主要问题,并提出了相应的解决措施。     

区域供热技术在希腊国内供热中的有效应用

希腊的区域供热始于1994年,采用热电联产技术向用户供热。预计目前在建项目完成以后,总装机容量将超过300MW,其中约85％为现有燃煤机组,其余16％主要是烧柴油和液化石油气的调峰机组。目前用户数量已超过25000户,供热建筑超过6000幢。由于区域供热价格具有竞争力,且初始投资成本低,所以时希腊而言尤其具有吸引力。随着希腊能源市场自由化以及输气管线的完善,区域供热技术将在能源和环保领域产生更大的效益。     

Should a small combined heat and power plant (CHP) open to its regional power and heat networks? Integrated economic,energy, and emergy evaluation of optimization plans for Jiufa CHP

The development of industrial ecology has led company managers to increasingly consider their company's niche in the regional system, and to develop optimization plans. We used emergy-based, ecological-economic synthesis to evaluate two optimization plans for the Jiufa Combined Heat and Power (CHP) Plant, Shandong China. In addition, we performed economic input–output analysis and energy analysis on the system. The results showed that appropriately incorporating a firm with temporary extra productivity into its regional system will help maximize the total productivity and improve ecological-economic efficiency and benefits to society, even without technical optimization of the firm itself. In addition, developing a closer relationship between a company and its regional system will facilitate the development of new optimization opportunities. Small coal-based CHP plants have lower-energy efficiency, higher environmental loading, and lower sustainability than large fossil fuel and renewable energy-based systems. The emergy exchange ratio (EER) proved to be an important index for evaluating the vitality of highly developed ecological-economic systems.     

Cogeneration plant in an olive sludge industry

Spain is the world’s main producer of olive oil, with an annual production approaching 1 million tons. A great amount of wet residues are generated – mainly sludge, thus favouring the development of energy plants for their treatment and/or elimination. Such installations require a simultaneous electric and thermal energy demand, and combined heat and power (CHP) systems might be the most adequate in certain cases. The economic viability of a CHP system in a sludge processing plant (sludge obtained from olive oil extraction industry) is analysed in the present work. Special attention is paid to the analysis and discussion of energy savings and environmental benefits.     

Estimating the power and number of microturbines in small-scale combined heat and power systems

Utilizing the combined heat and power (CHP) systems to produce both electricity and heat is growing rapidly due to their high efficiency and low emissions in domestic, commercial, and industrial applications. In the first two categories among available drivers, due to the compact size and low weight, microturbines are attractive choice. In this paper, by using an energy–economic analysis the type and number of the required microturbines for the specific electricity and heat load curves during a year were selected. For performing this task an objective function annual profit (AP) was introduced and maximized. The operation strategy and the payback period of the chosen system was also determined in this study.     

Excess heat from kraft pulp mills: Trade-offs between internal and external use in the case of Sweden—Part 1: Methodology

Excess heat from a kraft pulp mill can be used either internally to increase the level of efficiency in the mill, or externally for example as district heating. This paper presents an approach to investigate the competition between external and internal use through modelling the pulp mill and an energy company (ECO) within the same system boundary. Three different sizes of ECOs with different district heating demands are studied. To investigate the competitiveness of using industrial excess heat as district heating compared with other heat production techniques, the option of investing in excess heat use is introduced, along with the possibility for the ECO to invest in biomass combined heat and power (CHP), waste CHP and natural gas combined cycle (NGCC). To evaluate the robustness of the model, alternative solutions are identified and will be used as a comparison to the optimal solutions. The model has been verified by comparing the results with previous studies concerning kraft pulp mills and with related studies regarding district heating and real ECOs. Finally, the approach presented in this part of the study will be used in the second part in order to investigate the trade-off between internal and external use of excess heat under different future energy market scenarios.