生物質(zhì)發(fā)電是利用生物質(zhì)所具有的生物質(zhì)能進(jìn)行的發(fā)電,是可再生能源發(fā)電的一種,包括農(nóng)林廢棄物直接燃燒發(fā)電、農(nóng)林廢棄物氣化發(fā)電、垃圾焚燒發(fā)電、垃圾填埋氣發(fā)電、沼氣發(fā)電。
Biomass power generation is a type of renewable energy generation that utilizes the biomass energy possessed by biomass. It includes direct combustion of agricultural and forestry waste for power generation, gasification of agricultural and forestry waste for power generation, waste incineration for power generation, landfill gas for power generation, and biogas for power generation.
生物質(zhì)發(fā)電包括農(nóng)林廢棄物直接燃燒發(fā)電、農(nóng)林廢棄物氣化發(fā)電、垃圾焚燒發(fā)電、垃圾填埋氣發(fā)電、沼氣發(fā)電等。
Biomass power generation includes direct combustion of agricultural and forestry waste for power generation, gasification of agricultural and forestry waste for power generation, waste incineration for power generation, landfill gas for power generation, biogas for power generation, etc.
1、農(nóng)林廢棄物直接燃燒發(fā)電原理
1. Principle of direct combustion of agricultural and forestry waste for power generation
直接燃燒發(fā)電是將生物質(zhì)在鍋爐中直接燃燒,生產(chǎn)蒸汽帶動蒸汽輪機(jī)及發(fā)電機(jī)發(fā)電。生物質(zhì)直接燃燒發(fā)電的關(guān)鍵技術(shù)包括生物質(zhì)原料預(yù)處理、鍋爐防腐、鍋爐的原料適用性及燃料效率、蒸汽輪機(jī)效率等技術(shù)。
Direct combustion power generation refers to the direct combustion of biomass in a boiler to produce steam and drive a steam turbine and generator to generate electricity. The key technologies for biomass direct combustion power generation include biomass raw material pretreatment, boiler anti-corrosion, boiler raw material applicability and fuel efficiency, steam turbine efficiency, and other technologies.
燃燒秸稈發(fā)電時,秸稈入爐有多種方式:可以將秸稈打包、粉碎造粒(壓塊)、或打成粉或者與煤混合后末打入鍋爐。其生產(chǎn)過程為:將秸稈等生物質(zhì)加工成適于鍋爐燃燒的形式(粉狀或塊狀),送入鍋爐內(nèi)充分燃燒,使儲存于生物質(zhì)燃料中的化學(xué)能轉(zhuǎn)變成熱能;鍋爐內(nèi)的熱后產(chǎn)生飽和蒸汽,飽和蒸汽在過熱器內(nèi)繼續(xù)加熱成過熱蒸汽進(jìn)入汽輪機(jī),驅(qū)動汽輪發(fā)電機(jī)組旋轉(zhuǎn),將蒸汽的內(nèi)能轉(zhuǎn)換成機(jī)械能,后由發(fā)電機(jī)將機(jī)械能變成電能。
When burning straw for power generation, there are various ways for straw to be fed into the furnace: straw can be packaged, crushed into granules (crushed), or crushed into powder, or mixed with coal and finally fed into the boiler. The production process is to process biomass such as straw into a form suitable for boiler combustion (powder or block), and send it into the boiler for full combustion, converting the chemical energy stored in biomass fuel into thermal energy; The heat in the boiler generates saturated steam, which is further heated into superheated steam in the superheater and enters the turbine, driving the turbine generator unit to rotate, converting the internal energy of the steam into mechanical energy. Finally, the generator converts the mechanical energy into electrical energy.
2、生物質(zhì)氣化發(fā)電原理
2. Principles of biomass gasification for power generation
生物質(zhì)氣化發(fā)電技術(shù)是指生物質(zhì)在氣化爐中轉(zhuǎn)化為氣體燃料,經(jīng)凈化后直接進(jìn)入燃?xì)鈾C(jī)中燃燒發(fā)電或者直接進(jìn)入燃料電池發(fā)電。氣化發(fā)電的關(guān)鍵技術(shù)之一是燃?xì)鈨艋?,氣化出來的燃?xì)舛己幸欢ǖ碾s質(zhì),包括灰分、焦炭和焦油等,需經(jīng)過凈化系統(tǒng)把雜質(zhì)除去,以保證發(fā)電設(shè)備的正常運(yùn)行。
Biomass gasification power generation technology refers to the conversion of biomass into gas fuel in a gasifier, which is purified and directly burned in a gas engine for power generation or directly fed into a fuel cell for power generation. One of the key technologies for gasification power generation is gas purification. The gasified gas contains certain impurities, including ash, coke, and tar, which need to be removed through a purification system to ensure the normal operation of the power generation equipment.
生物質(zhì)氣化發(fā)電技術(shù)的基本原理,是把生物質(zhì)轉(zhuǎn)化為可燃?xì)?,再利用可燃?xì)馔苿尤細(xì)獍l(fā)電設(shè)備進(jìn)行發(fā)電。它既能解決生物質(zhì)難于燃用而且分布分散的缺點(diǎn),又可以充分發(fā)揮燃?xì)獍l(fā)電技術(shù)設(shè)備緊湊而且污染少的優(yōu)點(diǎn),所以,氣化發(fā)電是生物質(zhì)能有效、潔凈的利用方法之一。
The basic principle of biomass gasification power generation technology is to convert biomass into combustible gas, and then use combustible gas to drive gas power generation equipment for power generation. It can not only solve the shortcomings of biomass being difficult to burn and distributed dispersedly, but also fully utilize the advantages of compact equipment and low pollution of gas power generation technology. Therefore, gasification power generation is one of the most effective and clean utilization methods of biomass energy.
氣化發(fā)電過程主要包括三個方面:一是生物質(zhì)氣化,在氣化爐中把固體生物質(zhì)轉(zhuǎn)化為氣體燃料;二是氣體凈化,氣化出來的燃?xì)舛己幸欢ǖ碾s質(zhì),包括灰分、焦炭和焦油等,需經(jīng)過凈化系統(tǒng)把雜質(zhì)除去,以保證燃?xì)獍l(fā)電設(shè)備的正常運(yùn)行;三是燃?xì)獍l(fā)電,利用燃?xì)廨啓C(jī)或燃?xì)鈨?nèi)燃機(jī)進(jìn)行發(fā)電,有的工藝為了提高發(fā)電效率,發(fā)電過程可以增加余熱鍋爐和蒸汽輪機(jī)。
The gasification power generation process mainly includes three aspects: firstly, biomass gasification, which converts solid biomass into gas fuel in a gasifier; The second is gas purification. The gasified gas contains certain impurities, including ash, coke, and tar, which need to be removed through a purification system to ensure the normal operation of gas power generation equipment; The third is gas power generation, which utilizes gas turbines or gas internal combustion engines for power generation. In some processes, in order to improve power generation efficiency, waste heat boilers and steam turbines can be added to the power generation process.
3、沼氣發(fā)電原理
3. Principles of biogas power generation
沼氣發(fā)電主要原理是利用工農(nóng)業(yè)或城鎮(zhèn)生活中的大量有機(jī)廢棄物經(jīng)厭氧發(fā)酵處理產(chǎn)生的沼氣驅(qū)動發(fā)電機(jī)組發(fā)電。用于沼氣發(fā)電的設(shè)備主要為內(nèi)燃機(jī),一般由柴油機(jī)組或者天然氣機(jī)組改造而成。
The main principle of biogas power generation is to use a large amount of organic waste in industry, agriculture, or urban life to drive the power generation unit with biogas generated through anaerobic fermentation treatment. The equipment used for biogas power generation is mainly internal combustion engines, which are generally modified from diesel or natural gas units.
沼氣發(fā)電系統(tǒng)用一個密閉型的熱動力裝置(BTTPU),包括一套沼氣發(fā)動機(jī)、發(fā)電機(jī)和一臺帶出熱量的熱交換器。與現(xiàn)用的液體發(fā)酵主要區(qū)別在于物料有機(jī)質(zhì)不需要液化過程,在高溫厭氧環(huán)境下將生物質(zhì)原料直接裝入模塊式的密封發(fā)酵設(shè)備,在滲濾液環(huán)流作用下使干燥物料潮濕,經(jīng)過幾周時間,變成甲烷含量達(dá)70% ~ 80%的高質(zhì)量沼氣,通過沼氣發(fā)動機(jī)轉(zhuǎn)換成電能以及余熱利用。
The biogas power generation system uses a closed thermal power unit (BTTPU), which includes a biogas engine, generator, and a heat exchanger with heat output. The main difference from current liquid fermentation is that the organic matter of the material does not require a liquefaction process. In a high-temperature anaerobic environment, the biomass raw material is directly loaded into a modular sealed fermentation equipment. Under the circulation of the leachate, the dry material is moist, and after a few weeks, it becomes high-quality biogas with a methane content of 70% to 80%. It is converted into electricity through a biogas engine and waste heat is utilized.
4、垃圾焚燒發(fā)電
4. Waste incineration power generation
垃圾焚燒發(fā)電包括垃圾焚燒發(fā)電和垃圾氣化發(fā)電,其不僅可以解決垃圾處理的問題,同時還可以回收利用垃圾中的能量,節(jié)約資源,垃圾焚燒發(fā)電是利用垃圾在焚燒鍋爐中燃燒放出的熱量將水加熱獲得過熱蒸汽,推動汽輪機(jī)帶動發(fā)電機(jī)發(fā)電。垃圾焚燒技術(shù)主要有層狀燃燒技術(shù)、流化床燃燒技術(shù)、旋轉(zhuǎn)燃燒技術(shù)等。發(fā)展起來的氣化熔融焚燒技術(shù),包括垃圾在450°~640°溫度下的氣化和含碳灰渣在1300℃以上的熔融燃燒兩個過程,垃圾處理徹底,過程潔凈,并可以回收部分資源,被認(rèn)為是具有前景的垃圾發(fā)電技術(shù)。
Garbage incineration power generation includes garbage incineration power generation and garbage gasification power generation. It not only solves the problem of garbage treatment, but also recycles and utilizes the energy in garbage, saving resources. Garbage incineration power generation uses the heat released by garbage burning in the incineration boiler to heat water to obtain superheated steam, which drives the steam turbine to drive the generator to generate electricity. Waste incineration technology mainly includes layered combustion technology, fluidized bed combustion technology, rotary combustion technology, etc. The developed gasification and melting incineration technology includes two processes: gasification of waste at temperatures ranging from 450 ° to 640 ° C and melting combustion of carbon containing ash above 1300 ° C. The waste is thoroughly treated, the process is clean, and some resources can be recovered, making it the most promising waste power generation technology.
5、垃圾填埋氣發(fā)電
5. Landfill gas power generation
在垃圾填埋的過程中,因?yàn)樘盥駡隼逊朋w內(nèi)部缺少氧氣,垃圾中的有機(jī)物會發(fā)酵產(chǎn)生出大量的沼氣(填埋氣),平均每噸垃圾在填埋場壽命期內(nèi)可產(chǎn)生約100—200立方米的填埋氣體,其主要成分是甲烷、二氧化碳、硫化氫、氮等氣體。
During the process of landfilling, due to the lack of oxygen inside the landfill, the organic matter in the waste will ferment and produce a large amount of biogas (landfill gas). On average, each ton of waste can produce about 100-200 cubic meters of landfill gas during the lifespan of the landfill, which is mainly composed of methane, carbon dioxide, hydrogen sulfide, nitrogen, and other gases.
垃圾填埋氣發(fā)電采用了完整地垃圾沼氣收集和利用理念,通過的垃圾沼氣收集系統(tǒng),輸送系統(tǒng),沼氣凈化系統(tǒng)和沼氣發(fā)電系統(tǒng),將垃圾沼氣完全利用,產(chǎn)生電力,并入城市大電網(wǎng)之中,向電力用戶提供清潔能源。因此,現(xiàn)階段垃圾填埋氣發(fā)電是一種既能有效利用廢氣資源發(fā)電,又能減少空氣污染的無害化處理方式,是符合國家“節(jié)能減排”提倡的大方向目標(biāo)的項(xiàng)目,是典型的“低碳經(jīng)濟(jì)”。
Landfill gas power generation adopts a complete concept of garbage and biogas collection and utilization. Through advanced garbage and biogas collection systems, transportation systems, biogas purification systems, and biogas power generation systems, garbage and biogas are fully utilized to generate electricity, which is integrated into the urban power grid and provides clean energy to electricity users. Therefore, at present, landfill gas power generation is a harmless treatment method that can effectively utilize waste gas resources for power generation while reducing air pollution. It is a project that conforms to the national goal of "energy conservation and emission reduction" and is a typical "low-carbon economy".