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熱電廠煙氣脫硫除塵技術(shù)介紹

1 熱電廠煙氣脫硫除塵現(xiàn)狀

Current situation of flue gas desulfurization and dust removal in thermal power plants
1.1 除塵效果差,脫硫效率低
1.1 Poor dust removal effect and low desulfurization efficiency
熱電廠煙氣處理主要包括幾個(gè)方面:直接處理、化石燃料應(yīng)用和燃料處理,熱電廠生產(chǎn)運(yùn)營(yíng)過程中往往在燃料燃燒之前對(duì)煙氣進(jìn)行脫硫處理,然而由于脫硫除塵技術(shù)應(yīng)用存在很多問題,并且受到相關(guān)應(yīng)用條件的限制,使得熱電廠脫硫除塵效果較差。同時(shí),化石燃料燃燒過程中會(huì)產(chǎn)生大量的二氧化硫和粉塵,化石燃料燃燒脫硫是熱電廠煙氣脫硫除塵的關(guān)鍵,但是很多熱電廠的除硫效率較低,往往無法達(dá)到除硫技術(shù)標(biāo)準(zhǔn)。另外,化石燃料燃燒以后,有些熱電廠對(duì)煙氣中的粉塵和硫化物進(jìn)行處理,然而受到技術(shù)限制,再加上需要很多配套設(shè)施,所以熱電廠往往難以滿足煙氣脫硫除塵技術(shù)需求,不能直接對(duì)煙氣脫落除塵。
The flue gas treatment in thermal power plants mainly includes several aspects: direct treatment, fossil fuel application, and fuel treatment. During the production and operation of thermal power plants, flue gas is often desulfurized before fuel combustion. However, due to the many problems in the application of desulfurization and dust removal technology and the limitations of related application conditions, the desulfurization and dust removal effect of thermal power plants is poor. Meanwhile, the combustion process of fossil fuels generates a large amount of sulfur dioxide and dust. Fossil fuel combustion desulfurization is the key to flue gas desulfurization and dust removal in thermal power plants. However, many thermal power plants have low sulfur removal efficiency and often cannot meet the sulfur removal technology standards. In addition, after the combustion of fossil fuels, some thermal power plants treat dust and sulfides in the flue gas. However, due to technological limitations and the need for many supporting facilities, thermal power plants often find it difficult to meet the requirements of flue gas desulfurization and dust removal technology, and cannot directly remove and remove dust from the flue gas.
1.2 技術(shù)創(chuàng)新不足
1.2 Insufficient technological innovation
近年來,煤化石燃料逐漸被電力能源代替,很多燃煤鍋爐已經(jīng)無法滿足電力生產(chǎn)需求,煙氣脫硫除塵技術(shù)應(yīng)用和推廣受到較大限制。和發(fā)達(dá)國家相比,我國熱電廠在生產(chǎn)技術(shù)方面還存在一段距離,由于技術(shù)創(chuàng)新不足,熱電廠的煙氣脫硫除塵處理效果較差,造成熱電廠往往難以控制煙氣的含硫量。
In recent years, coal fossil fuels have gradually been replaced by electric energy, and many coal-fired boilers are no longer able to meet the needs of power production. The application and promotion of flue gas desulfurization and dust removal technology are greatly limited. Compared with developed countries, there is still a gap in production technology for thermal power plants in China. Due to insufficient technological innovation, the flue gas desulfurization and dust removal treatment effect of thermal power plants is poor, making it difficult for them to control the sulfur content of flue gas.
生物脫硫
1.3 資金投入不足
1.3 Insufficient capital investment
很多熱電廠對(duì)于煙氣脫硫除塵技術(shù)的資金投入不足,很多生產(chǎn)運(yùn)營(yíng)設(shè)備比較落后,更新?lián)Q代緩慢,由于缺少投入資金,煙氣脫硫除塵技術(shù)應(yīng)用存在很多困難,這直接影響了熱電廠的煙氣脫落除塵效果。
Many thermal power plants have insufficient investment in flue gas desulfurization and dust removal technology, and many production and operation equipment are relatively backward, with slow updates. Due to the lack of investment funds, there are many difficulties in the application of flue gas desulfurization and dust removal technology, which directly affects the effectiveness of flue gas separation and dust removal in thermal power plants.
2 熱電廠煙氣脫硫除塵技術(shù)
2. Desulfurization and dust removal technology for flue gas in thermal power plants
2.1 濕法脫硫除塵
2.1 Wet desulfurization and dust removal
(1)氧化鎂法。氧化鎂法主要是對(duì)煙道氣體使用氧化鎂漿液進(jìn)行脫硫,熱電廠煙氣和氧化鎂漿液接觸發(fā)生化學(xué)反應(yīng)會(huì)產(chǎn)生*和亞*,然后再配合碳粉,利用還原作用產(chǎn)生氧化鎂。這種氧化鎂脫硫法可獲取二氧化硫,并且可以直接加工成硫酸。
(1) Magnesium oxide method. The magnesium oxide method mainly uses magnesium oxide slurry for desulfurization of flue gas. The chemical reaction between the flue gas of a thermal power plant and the magnesium oxide slurry will produce * and sub *, which are then combined with carbon powder to produce magnesium oxide through reduction. This magnesium oxide desulfurization method can obtain sulfur dioxide and can be directly processed into sulfuric acid.
(2)石灰乳法。熱電廠煙氣脫硫除塵采用石灰乳法,其可發(fā)生兩種化學(xué)反應(yīng),一方面,二氧化硫和石灰發(fā)生化學(xué)反應(yīng)生成亞硫酸鈣;另一方面,在空氣環(huán)境中亞硫酸鈣和氧氣接觸以后生成硫酸鈣。這種石灰乳法在熱電廠煙氣脫硫除塵中的應(yīng)用,不僅原料來源容易,操作簡(jiǎn)單,而且脫硫流程簡(jiǎn)單,成本較低。在實(shí)際應(yīng)用中應(yīng)注意硫酸鈣利用和設(shè)備結(jié)垢問題。
(2) Lime milk method. The flue gas desulfurization and dust removal in thermal power plants adopts the lime milk method, which can undergo two chemical reactions. On the one hand, sulfur dioxide and lime undergo a chemical reaction to produce calcium sulfite; On the other hand, in the air environment, calcium sulfate is generated after contact with oxygen and calcium sulfite. The application of this lime milk method in flue gas desulfurization and dust removal in thermal power plants not only has an easy source of raw materials and simple operation, but also has a simple desulfurization process and lower cost. In practical applications, attention should be paid to the utilization of calcium sulfate and equipment scaling issues.
(3)亞鈉法。亞鈉法在煙氣脫硫除塵中的應(yīng)用,主要利用Na2CO3溶液,二氧化硫和Na2CO3溶液發(fā)生化學(xué)反應(yīng),生成亞硫酸氫鈉和亞硫酸鈉,并且亞硫酸氫鈉和亞硫酸鈉可以直接溶解在水中,不會(huì)引起脫硫除塵設(shè)備發(fā)生結(jié)垢問題,但是無法回收利用亞硫酸鹽,只能轉(zhuǎn)變?yōu)閺U氣液體。
(3) Sodium sulfite method. The application of sodium sulfite method in flue gas desulfurization and dust removal mainly utilizes Na2CO3 solution, sulfur dioxide and Na2CO3 solution to undergo chemical reaction, generating sodium bisulfite and sodium sulfite. Sodium bisulfite and sodium sulfite can be directly dissolved in water, without causing scaling problems in desulfurization and dust removal equipment. However, sulfite cannot be recycled and can only be converted into waste gas liquid.
2.2 干法脫硫除塵
2.2 Dry desulfurization and dust removal
(1)沸石吸附。沸石吸附是一種重要的干法煙氣脫硫除塵技術(shù),這種方法主要包括冷卻、再生、解吸、吸附等環(huán)節(jié),在實(shí)際應(yīng)用中沸石吸附煙氣脫硫除塵流程比較簡(jiǎn)單,而且也不會(huì)發(fā)生設(shè)備結(jié)垢和廢水淤泥等問題,根據(jù)熱電廠煙氣脫硫除塵技術(shù)要求,在320攝氏度環(huán)境條件下對(duì)熱電廠煙氣用干燥空氣吹洗,可實(shí)現(xiàn)沸石回收再生利用,不僅可實(shí)現(xiàn)良好脫硫效果,而且生產(chǎn)成本較低。
(1) Zeolite adsorption. Zeolite adsorption is an important dry flue gas desulfurization and dust removal technology, which mainly includes cooling, regeneration, desorption, adsorption and other links. In practical applications, the process of zeolite adsorption flue gas desulfurization and dust removal is relatively simple, and there are no problems such as equipment scaling and wastewater sludge. According to the requirements of flue gas desulfurization and dust removal technology in thermal power plants, dry air is used to blow and wash the flue gas in a 320 degree Celsius environment, It can achieve the recycling and reuse of zeolite, not only achieving good desulfurization effect, but also lower production cost.
(2)噴霧干燥。熱電廠煙氣脫硫除塵利用噴霧干燥法,二氧化硫和石灰乳發(fā)生化學(xué)反應(yīng)以后轉(zhuǎn)換為亞硫酸鈣,從而實(shí)現(xiàn)熱電廠煙氣脫硫,通過噴霧方式,使石灰乳和二氧化硫充分接觸,從而*地發(fā)生化學(xué)反應(yīng),并且生產(chǎn)的亞硫酸鈣經(jīng)過干燥處理,還能夠利用相關(guān)設(shè)備回收起來。噴霧干燥處理法在實(shí)際應(yīng)用中,工藝流程簡(jiǎn)單,運(yùn)行費(fèi)用和應(yīng)用成本較低,相關(guān)脫硫設(shè)備也不會(huì)發(fā)生結(jié)垢,并且具有較高的脫硫效率,但是在應(yīng)用這種方法時(shí),應(yīng)做好后期的淤泥和廢水處理。
(2) Spray drying. The spray drying method is used for flue gas desulfurization and dust removal in the thermal power plant. Sulfur dioxide and lime milk are converted into calcium sulfite after chemical reaction, so as to realize flue gas desulfurization in the thermal power plant. Through spray, lime milk and sulfur dioxide are fully contacted, so that chemical reaction can occur. The calcium sulfite produced can also be recycled by using relevant equipment after drying. In the practical application of spray drying treatment method, the process flow is simple, the operation cost and application cost are low, the relevant desulfurization equipment will not scale, and has a high desulfurization efficiency. However, when this method is applied, the sludge and wastewater treatment in the later period should be done well.
(3)活性焦吸附?;钚越故且环N重要的吸附劑,其具有更加優(yōu)越的吸附容量和性能,并且熱穩(wěn)定性較好,即使將這種活性焦吸附劑放在800攝氏度的高溫環(huán)境中也可以保持沒有損壞,所以其具有持續(xù)的吸附活力。通過在熱電廠煙氣脫硫除塵中應(yīng)用活性焦吸附劑,可直接將吸附的二氧化硫加工制成硫酸,在實(shí)際應(yīng)用中,這種活性焦不僅可作為吸附劑,還可作為催化劑,應(yīng)用價(jià)值較高。
(3) Activated coke adsorption. Activated coke is an important adsorbent with superior adsorption capacity and performance, as well as good thermal stability. Even when placed in a high temperature environment of 800 degrees Celsius, this activated coke adsorbent can remain undamaged, resulting in sustained adsorption activity. By applying activated coke adsorbent in flue gas desulfurization and dust removal in thermal power plants, the adsorbed sulfur dioxide can be directly processed into sulfuric acid. In practical applications, this activated coke can not only serve as an adsorbent, but also as a catalyst, with high application value.
2.3 干濕結(jié)合脫硫除塵
2.3 Dry wet combined desulfurization and dust removal
干濕結(jié)合脫硫除塵技術(shù)在熱電廠煙氣脫硫除塵中的應(yīng)用,其將濕法和干法有效結(jié)合起來,通過建立立式塔,這種干濕搭配進(jìn)行煙氣脫硫除塵的效果較高,非常適合中小型燃煤鍋爐煙氣處理,但是熱電廠需要增加資金投入,加大對(duì)干濕結(jié)合脫硫除塵的分析和研究,推動(dòng)其更加廣泛的應(yīng)用。
The application of wet dry combined desulfurization and dust removal technology in flue gas desulfurization and dust removal in thermal power plants effectively combines wet and dry methods. By establishing a vertical tower, this wet dry combination has a high effect on flue gas desulfurization and dust removal, which is very suitable for small and medium-sized coal-fired boiler flue gas treatment. However, thermal power plants need to increase capital investment, increase analysis and research on wet dry combined desulfurization and dust removal, and promote its wider application.
3 熱電廠煙氣脫硫除塵技術(shù)應(yīng)用發(fā)展
Development of application of flue gas desulfurization and dust removal technology in 3 thermal power plants
3.1 加強(qiáng)技術(shù)管理
3.1 Strengthen technical management
當(dāng)前,我國很多地區(qū)熱電廠還在使用中小型燃煤鍋爐,所以相關(guān)部門應(yīng)加大對(duì)中小型燃煤鍋爐煙氣脫硫除塵技術(shù)的分析和研究,及時(shí)彌補(bǔ)煙氣脫硫除塵的問題。相關(guān)工作人員應(yīng)加強(qiáng)煙氣脫硫除塵技術(shù)管理,積極發(fā)展和完善現(xiàn)有技術(shù),并且進(jìn)一步豐富脫硫除塵技術(shù),仔細(xì)研究煙氣脫硫除塵技術(shù)中存在的弊端,基于特電廠生產(chǎn)運(yùn)營(yíng)的具體情況,研發(fā)新型煙氣脫硫除塵技術(shù)。
Currently, many thermal power plants in China are still using small and medium-sized coal-fired boilers. Therefore, relevant departments should increase their analysis and research on flue gas desulfurization and dust removal technology for small and medium-sized coal-fired boilers, and timely make up for the problems of flue gas desulfurization and dust removal. Relevant personnel should strengthen the management of flue gas desulfurization and dust removal technology, actively develop and improve existing technologies, and further enrich desulfurization and dust removal technology. They should carefully study the drawbacks of flue gas desulfurization and dust removal technology and develop new flue gas desulfurization and dust removal technologies based on the specific production and operation of special power plants.
3.2 加大技術(shù)創(chuàng)新
3.2 Increase technological innovation
熱電廠煙氣脫硫除塵技術(shù)的應(yīng)用和發(fā)展必須要解決設(shè)備防腐問題,因此相關(guān)企業(yè)應(yīng)重點(diǎn)研究煙氣脫硫除塵設(shè)備防腐性能,為了進(jìn)一步提高煙氣脫硫除塵設(shè)備的防腐性能,應(yīng)仔細(xì)研究設(shè)備應(yīng)用材料防腐性,全面考慮不同應(yīng)用材料的實(shí)際防腐性能,選擇耐腐蝕的材料設(shè)備,延長(zhǎng)煙氣脫硫除塵設(shè)備的使用壽命,還可結(jié)合煙氣脫硫除塵設(shè)備的運(yùn)行性能,采取合理、有效的配套措施,例如將有機(jī)涂層設(shè)置在設(shè)備材料表面,使用玻璃鋼材料,這種方法可有效防止煙氣脫硫除塵設(shè)備發(fā)生銹蝕,而且也不會(huì)產(chǎn)生設(shè)備結(jié)垢問題。
The application and development of flue gas desulfurization and dust removal technology in thermal power plants must solve the problem of equipment anti-corrosion. Therefore, relevant enterprises should focus on researching the anti-corrosion performance of flue gas desulfurization and dust removal equipment. In order to further improve the anti-corrosion performance of flue gas desulfurization and dust removal equipment, the anti-corrosion properties of equipment application materials should be carefully studied, and the actual anti-corrosion performance of different application materials should be comprehensively considered. corrosion-resistant materials and equipment should be selected to extend the service life of flue gas desulfurization and dust removal equipment, Reasonable and effective supporting measures can also be taken based on the operational performance of flue gas desulfurization and dust removal equipment, such as placing organic coatings on the surface of equipment materials and using fiberglass materials. This method can effectively prevent corrosion of flue gas desulfurization and dust removal equipment and will not cause equipment scaling problems.
3.3 加大資金投入
3.3 Increase capital investment
為了進(jìn)一步推動(dòng)熱電廠煙氣脫硫除塵技術(shù)的應(yīng)用和推廣,應(yīng)加大這方面的資金投入,強(qiáng)化熱電廠的責(zé)任意識(shí),高度重視煙氣脫硫除塵問題,根據(jù)熱電廠生產(chǎn)運(yùn)營(yíng)的實(shí)際情況,配備的煙氣脫硫除塵設(shè)備,引進(jìn)專業(yè)技術(shù)人員和研發(fā)人員,積極調(diào)整熱電廠的煙氣脫硫除塵方案,設(shè)立專門的煙氣脫硫除塵技術(shù)研發(fā)資金,完善相關(guān)配套設(shè)施,不斷提高煙氣脫硫除塵技術(shù)水平。
In order to further promote the application and promotion of flue gas desulfurization and dust removal technology in thermal power plants, it is necessary to increase investment in this area, strengthen the sense of responsibility of thermal power plants, attach great importance to flue gas desulfurization and dust removal issues, equip * flue gas desulfurization and dust removal equipment according to the actual production and operation of thermal power plants, introduce professional technical personnel and R&D personnel, and actively adjust the flue gas desulfurization and dust removal plan of thermal power plants, Establish dedicated research and development funds for flue gas desulfurization and dust removal technology, improve relevant supporting facilities, and continuously improve the level of flue gas desulfurization and dust removal technology.
 

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