1、生物質(zhì)直接燃燒發(fā)電
1. Direct combustion of biomass for power generation
生物質(zhì)直接燃燒發(fā)電是指把生物質(zhì)原料送入適合生物質(zhì)燃燒的特定鍋爐中直接燃燒,產(chǎn)生蒸汽,帶動(dòng)蒸汽輪機(jī)及發(fā)電機(jī)發(fā)電。已開發(fā)應(yīng)用的生物質(zhì)鍋爐種類較多,如木材鍋爐、甘蔗渣鍋爐、稻殼鍋爐、秸稈鍋爐等。生物質(zhì)直接燃燒發(fā)電的關(guān)鍵技術(shù)包括原料預(yù)處理,生物質(zhì)鍋爐防腐,提高生物質(zhì)鍋爐的多種原料適用性及燃燒效率、蒸汽輪機(jī)效率等技術(shù)。
Biomass direct combustion power generation refers to the direct combustion of biomass raw materials into a specific boiler suitable for biomass combustion, generating steam to drive steam turbines and generators to generate electricity. There are many types of biomass boilers that have been developed and applied, such as wood boilers, bagasse boilers, rice husk boilers, straw boilers, etc. The key technologies for biomass direct combustion power generation include raw material pretreatment, anti-corrosion of biomass boilers, improving the applicability and combustion efficiency of various raw materials for biomass boilers, and steam turbine efficiency.
生物質(zhì)直接燃燒發(fā)電技術(shù)中的生物質(zhì)燃燒方式包括固定床燃燒或流化床燃燒等方式。固定床燃燒對(duì)生物質(zhì)原料的預(yù)處理要求較低,生物質(zhì)經(jīng)過(guò)簡(jiǎn)單處理甚至無(wú)須處理就可投入爐排爐內(nèi)燃燒。流化床燃燒要求將大塊的生物質(zhì)原料預(yù)先粉碎至易于流化的粒度,其燃燒效率和強(qiáng)度都比固定床高。
The biomass combustion methods in biomass direct combustion power generation technology include fixed bed combustion or fluidized bed combustion. Fixed bed combustion requires low pre-treatment requirements for biomass raw materials, and biomass can be put into a grate furnace for combustion after simple treatment or even without treatment. Fluidized bed combustion requires pre crushing large biomass raw materials to a particle size that is easy to fluidize, with higher combustion efficiency and intensity than fixed beds.
另外,由于我國(guó)的生物質(zhì)種類多,成分復(fù)雜,收集運(yùn)輸困難,而且主要的農(nóng)業(yè)廢棄物受到農(nóng)業(yè)生產(chǎn)和季節(jié)性的影響不能保證全年供應(yīng),所以與燃煤鍋爐對(duì)燃料單一性的要求不同,生物質(zhì)鍋爐要求能適應(yīng)多種生物質(zhì)原料,以保證燃料供應(yīng)的穩(wěn)定性。
In addition, due to the large variety and complex composition of biomass in China, collection and transportation difficulties, and the impact of agricultural production and seasonality on the main agricultural wastes, which cannot ensure the annual supply, unlike coal-fired boilers, which require fuel uniformity, biomass boilers are required to be able to adapt to a variety of biomass raw materials to ensure the stability of fuel supply.
我國(guó)的生物質(zhì)鍋爐和小型蒸汽輪機(jī)技術(shù)已基本成熟,但設(shè)備規(guī)模較小,參數(shù)較低,與進(jìn)口設(shè)備相比效率較低。生物質(zhì)直接燃燒發(fā)電技術(shù)比較成熟,在大規(guī)模生產(chǎn)條件下具有較高的效率。該技術(shù)在我國(guó)應(yīng)用較少,因?yàn)樗笊镔|(zhì)資源集中,數(shù)量巨大,如果大規(guī)模收集或運(yùn)輸生物質(zhì),將提高原料成本,因此該技術(shù)比較適于現(xiàn)代化大農(nóng)場(chǎng)或大型加工廠的廢物處理。
The technology of biomass boilers and small steam turbines in China has been basically mature, but the equipment scale is small, the parameters are low, and the efficiency is lower compared to imported equipment. Biomass direct combustion power generation technology is relatively mature and has high efficiency under large-scale production conditions. This technology is rarely used in China because it requires concentrated biomass resources and a large amount. If biomass is collected or transported on a large scale, it will increase the cost of raw materials. Therefore, this technology is more suitable for waste treatment in modern large farms or large processing plants.
2、生物質(zhì)氣化發(fā)電
2. Biomass gasification for power generation
生物質(zhì)氣化發(fā)電是指生物質(zhì)在氣化爐中氣化生成可燃?xì)怏w,經(jīng)過(guò)凈化后驅(qū)動(dòng)內(nèi)燃機(jī)或小型燃?xì)廨啓C(jī)發(fā)電。氣化爐應(yīng)對(duì)不同種類的生物質(zhì)原料有較強(qiáng)的適應(yīng)性。內(nèi)燃機(jī)一般由柴油機(jī)或天然氣機(jī)改造而成,以適應(yīng)生物質(zhì)燃?xì)鉄嶂递^低的要求;燃?xì)廨啓C(jī)要求容量小,適于燃燒高雜質(zhì)、低熱值的生物質(zhì)燃?xì)狻?br />
Biomass gasification power generation refers to the gasification of biomass in a gasifier to generate combustible gas, which is purified to drive an internal combustion engine or small gas turbine for power generation. Gasifiers have strong adaptability to different types of biomass feedstock. Internal combustion engines are generally modified from diesel or natural gas engines to meet the requirements of low calorific value of biomass gas; The gas turbine requires a small capacity and is suitable for burning biomass gas with high impurities and low calorific value.
生物質(zhì)氣化發(fā)電包括小型氣化發(fā)電和中型氣化發(fā)電2種模式:小型氣化發(fā)電采用簡(jiǎn)單的氣化—內(nèi)燃機(jī)發(fā)電工藝,發(fā)電效率一般在14%-20%,規(guī)模一般小于3MW。中型氣化發(fā)電除了采用氣化—內(nèi)燃機(jī)(或燃?xì)廨啓C(jī))發(fā)電工藝外,同時(shí)增加余熱回收和發(fā)電系統(tǒng),氣化發(fā)電系統(tǒng)的總效率可達(dá)到25%-35%。
Biomass gasification power generation includes two modes: small-scale gasification power generation and medium-sized gasification power generation: small-scale gasification power generation uses a simple gasification internal combustion engine power generation process, with a power generation efficiency of generally 14% - 20%, and a scale of generally less than 3MW. In addition to adopting the gasification internal combustion engine (or gas turbine) power generation process, medium-sized gasification power generation also adds a waste heat recovery and power generation system. The total efficiency of the gasification power generation system can reach 25% - 35%.
另外,大規(guī)模的氣化—燃?xì)廨啓C(jī)聯(lián)合循環(huán)發(fā)電系統(tǒng)作為的生物質(zhì)氣化發(fā)電技術(shù),能耗比常規(guī)系統(tǒng)低,總體效率高于40%,但關(guān)鍵技術(shù)仍未成熟,尚處在示范和研究階段。
In addition, as an advanced biomass gasification power generation technology, large-scale gasification gas turbine combined cycle power generation systems have lower energy consumption and overall efficiency higher than 40% compared to conventional systems. However, key technologies are still immature and are still in the demonstration and research stage.