Small Scale Biomass-Fired CHP System

该项目旨在开发一种新颖的，同类首创的10千瓦生物质燃烧热电联产（CHP）系统，适用于公共和大型住宅建筑。该项目的具体目标是：(1)证明通过生物质燃烧结合有机朗肯涡轮循环发电的概念适用于小至10千瓦时的生物质燃料热电联产系统；(2)设计、建设并评价国内首个10kwe生物质热电联产系统；(3)为拟建的10千瓦生物质热电联产系统建立计算机模型。热电联产（CHP）是现场发电和利用发电过程中产生的副产品。对于广泛的公共和大型住宅建筑，热电联产可以提供一种经济的方法来提供热量和电力，而这种方法比传统方法（例如由燃气锅炉提供热量和由电网提供电力）对环境的危害较小。然而，市场上几乎所有的热电联产系统都是由化石燃料驱动的，主要是天然气和石油。为了进一步减少公共和大型住宅建筑的能源使用所产生的温室气体排放，必须使用基于可再生燃料（如生物质）的热电联产系统。基于燃烧与蒸汽朗肯涡轮循环相结合的生物质发电是目前最发达的技术。然而，蒸汽驱动的朗肯汽轮机发电由于其固有的低发电效率和高资金成本，不适合用于小于100kwe的生物质发电机组或热电联产系统。适用于公共和大型住宅建筑（约10千瓦时）的生物质发电机或热电联产系统在世界上任何地方都没有。为了满足公共和大型住宅建筑部门日益增长的市场需求，迫切需要开发一种新的生物质燃料热电联产系统（约10千瓦时）。新的10kw额定生物质燃料系统必须采用新的发电概念来开发，以确保热电联产系统安全、可靠、高效和低资本成本。本次合作项目提出的热电联产系统具有以下创新特点：(1)首创；(2)利用生物质燃烧结合有机朗肯循环（ORC）发电。这将是基于orc的发电首次应用于10千瓦时的生物质燃料热电联产系统。(3)生物质锅炉和有机朗肯水轮机循环通过导热油加热循环而不是水/蒸汽加热循环耦合。(4)采用一种新型的、经济的ORC汽轮机与所提出的热电联产系统配合使用。ORC涡轮机将由廉价的、现成的制冷剂压缩机改造而成。在2千瓦机组上进行的初步试验表明，这种新型ORC水轮机不仅比以往研究中使用的水轮机更经济、更高效、更可靠。(5)在ORC过程中只考虑对环境友好的工作流体。拟议的项目很可能是一个可行的、商业上可开发的产品，这将直接使申请人及其项目合作伙伴受益，他们将与申请人在欧洲的机构合作，利用拟议的研究成果。拟议的研究也将使学术界和包括生物质技术和涡轮机技术在内的几个工业部门受益。它将对小型生物质加热和热电联产系统以及小型orc涡轮机的发展产生直接影响。该项目的长期效益包括为公共和大型住宅建筑部门提供更可持续的热电联产发电，以及保护全球环境。

The project aims to develop a novel, first-of-its-kind 10 kWe biomass-fired combined heat and power (CHP) system suitable for public and large domestic buildings' application. The specific objectives of the project are:(1) To prove that the concept of power generation through biomass combustion combined with an organic Rankine turbine cycle is suitable for biomass-fuelled CHP systems as small as 10 kWe;(2) To design, construct and evaluate the first-of-its-kind 10 kWe biomass-fired CHP system;(3) To develop a computer model for the proposed 10 kWe biomass-fired CHP system.Combined Heat and Power (CHP) is the on-site generation of electricity and the utilisation of the heat that is a by-product of the generation process. For a wide range of public and large domestic buildings, CHP can offer an economical method of providing heat and power which is less environmentally harmful than conventional methods (e.g. heat supplied by a gas boiler and electricity supplied by the grid). However, almost all of the CHP systems on the market are fuelled by fossil fuels, mainly natural gas and oil. To further reduce greenhouse emissions resulted from the energy use in public and large domestic buildings, CHP systems based on renewable fuels, such as biomass, have to be used. Generating electricity from biomass based on combustion combined with a steam Rankine turbine cycle is the most developed technology at the present time. However, the steam-driven Rankine turbine power generation is not suitable for biomass generators or CHP systems smaller than 100 kWe because of its inherent low electricity generation efficiency and high capital costs. Biomass generators or CHP systems suitable for use in public and large domestic buildings (in the order of 10 kWe) are not available anywhere in the world. To meet the expected increasing market demand from the sector of public and large domestic buildings, a new biomass-fuelled CHP system (ca. 10kWe) has to be developed as a matter of urgency. The new 10kWe-rated biomass-fuelled system has to be developed with a new concept of power generation which ensures the CHP system to be safe, reliable, of high efficiency and of low capital costs. The CHP system proposed in this collaborative project has the following innovative features:(1) It will be the first-of-its kind;(2) It uses biomass combustion combined with an organic Rankine cycle (ORC) to generate electricity. It will be the first time that the ORC-based power generation is applied to a biomass-fuelled CHP system as small as 10 kWe.(3) The biomass boiler and the organic Rankine turbine cycle are coupled via a thermal oil heating cycle instead of a water/steam heating cycle. (4) A novel, economical ORC turbine is used with the proposed CHP system. The ORC turbine is to be modified from a cheap, bought off the shelf, refrigerant compressor. The preliminary tests on the 2kWe-rated unit have indicated that this new type of ORC turbine is not only more economical but also more efficient and more reliable than those used in the previous studies.(5) Only environment-friendly working fluids will be considered in the ORC process.The proposed project is likely to indicate a viable, commercially exploitable product and this will directly benefit the applicants and their partners of the project who will exploit the outcomes of the proposed research in collaboration with the applicants' institutions in Europe. The proposed research will also benefit academia, and several industrial sectors including biomass technology and turbine technology. It will have a direct impact on the development of small-scale biomass heating and CHP systems and small-scale ORC-turbines. The long term benefits of the project include more sustainable CHP generation for the sector of public and large domestic buildings and protection of the global environment.