隨著焦化行業(yè)的發(fā)展，焦?fàn)t煤氣除部分返回焦?fàn)t加熱外，剩余主要作為城市煤氣，還有相當(dāng)數(shù)量的焦?fàn)t煤氣會通過火炬燃燒放空。據(jù)估計(jì)每年約有350×108m3以上的焦?fàn)t煤氣未被有效利用而付之一炬，這不僅造成環(huán)境污染，還浪費(fèi)了大量能源。根據(jù)焦?fàn)t煤氣的特點(diǎn)（含氫量高），我國焦化行業(yè)應(yīng)進(jìn)一步開發(fā)出符合企業(yè)特點(diǎn)的應(yīng)用技術(shù)，進(jìn)而實(shí)現(xiàn)煤氣資源的優(yōu)化開發(fā)利用，增加焦?fàn)t煤氣的利用價(jià)值，增強(qiáng)煉焦行業(yè)的整體競爭力。近年來，我國焦?fàn)t煤氣利用程度不斷提高，在開發(fā)利用技術(shù)方面進(jìn)行了一系列探索，本文總結(jié)出七種常用的焦?fàn)t煤氣綜合利用節(jié)能技術(shù)。

　　With the development of the coking industry, in addition to some returning to the coke oven for heating, the remaining coke oven gas is mainly used as urban gas, and a considerable amount of coke oven gas will be burned and released through torches. It is estimated that over 350 × 108m3 of coke oven gas is burned every year without being effectively utilized, which not only causes environmental pollution but also wastes a large amount of energy. Based on the characteristics of coke oven gas (high hydrogen content), China's coking industry should further develop application technologies that are in line with the characteristics of enterprises, in order to optimize the development and utilization of gas resources, increase the utilization value of coke oven gas, and enhance the overall competitiveness of the coking industry. In recent years, the utilization level of coke oven gas in China has been continuously improved, and a series of explorations have been made in the development and utilization technology. This article summarizes seven commonly used energy-saving technologies for comprehensive utilization of coke oven gas.

　　一、焦?fàn)t煤氣用作氣體燃料焦?fàn)t煤氣是優(yōu)質(zhì)的中熱值氣體燃料，其熱值為17兆焦~19兆焦/標(biāo)準(zhǔn)立方米，煤氣的主要成分（體積百分比）為氫55％~60％、甲烷23％~27%、一氧化碳5％~8％，含兩個(gè)以上的碳原子的不飽和烴2％~4％，以及少量的二氧化碳、氮、氧等。由于我國油氣資源缺乏，為解決大中城市民用燃?xì)饩o張的問題，20世紀(jì)80年代焦?fàn)t煤氣曾一度廣泛應(yīng)用于民用燃?xì)忸I(lǐng)城。

　　1、 Coke oven gas is used as a gas fuel. Coke oven gas is a high-quality medium calorific value gas fuel with a calorific value of 17 to 19 megajoules per standard cubic meter. The main components (volume percentage) of the gas are hydrogen 55% to 60%, methane 23% to 27%, carbon monoxide 5% to 8%, unsaturated hydrocarbons containing two or more carbon atoms 2% to 4%, and small amounts of carbon dioxide, nitrogen, oxygen, etc. Due to the lack of oil and gas resources in China, coke oven gas was widely used in the civilian gas industry in the 1980s to solve the problem of gas shortage in large and medium-sized cities.

　　目前，在天然氣還沒有通達(dá)而焦化行業(yè)有一定基礎(chǔ)的地區(qū)，焦?fàn)t煤氣仍是民用煤氣和其他工業(yè)生產(chǎn)的主要?dú)怏w燃料提供者。如我國景德鎮(zhèn)等地將焦?fàn)t煤氣用作陶瓷廠窯爐的加熱燃料，生產(chǎn)出優(yōu)質(zhì)的陶瓷制品。此外，焦?fàn)t煤氣還可用作水泥和玻璃等工業(yè)生產(chǎn)的燃料。

　　At present, in areas where natural gas is not yet accessible but the coking industry has a certain foundation, coke oven gas remains the main gas fuel provider for civilian gas and other industrial production. In places like Jingdezhen in China, coke oven gas is used as heating fuel for ceramic factory kilns to produce high-quality ceramic products. In addition, coke oven gas can also be used as fuel for industrial production such as cement and glass.

　　二、利用焦?fàn)t煤氣發(fā)電由于焦?fàn)t普遍采用了高效的煙氣余熱回收技術(shù)，約有50％~55％的焦?fàn)t煤氣富余，我國許多焦化企業(yè)將剩余的焦?fàn)t煤氣用于發(fā)電。焦?fàn)t煤氣發(fā)電有三種方式，分別為蒸汽發(fā)電（熱電聯(lián)產(chǎn)）、燃?xì)廨啓C(jī)發(fā)電和內(nèi)燃機(jī)發(fā)電，目前這幾種發(fā)電方式在國內(nèi)均有應(yīng)用，技術(shù)成熟。如果焦化企業(yè)與高電耗生產(chǎn)匹配或與發(fā)供電企業(yè)聯(lián)營，且上網(wǎng)電價(jià)合適，焦?fàn)t煤氣用于發(fā)電可作為優(yōu)先選擇的技術(shù)路之一。其運(yùn)行與管理簡便，生產(chǎn)作業(yè)間長，可采取多種方式，企業(yè)收益穩(wěn)定。1、蒸汽發(fā)電，熱電聯(lián)產(chǎn)供熱與發(fā)電兼用

　　2、 Due to the widespread use of efficient flue gas waste heat recovery technology in coke ovens, about 50% to 55% of coke oven gas is surplus. Many coking enterprises in China use the surplus coke oven gas for power generation. There are three ways to generate electricity from coke oven gas, namely steam power generation (cogeneration), gas turbine power generation, and internal combustion engine power generation. Currently, these power generation methods are widely used in China and have mature technologies. If coking enterprises are matched with high electricity consumption production or jointly operated with power generation and supply enterprises, and the on grid electricity price is appropriate, using coke oven gas for power generation can be one of the preferred technological paths. Its operation and management are simple, the production operation is long, multiple methods can be adopted, and the enterprise's income is stable. 1. Steam power generation, combined heat and power generation for both heating and power generation

　　蒸汽發(fā)電由鍋爐-凝氣式氣輪機(jī)-發(fā)電機(jī)組成。該工藝以焦?fàn)t煤氣作為熱源燃燒鍋爐，生成高壓蒸汽，用以帶動汽輪機(jī)、發(fā)電機(jī)而發(fā)電。蒸汽發(fā)電技術(shù)過關(guān)、成熟可靠。在我國焦化行業(yè)應(yīng)用較廣泛，但其系統(tǒng)復(fù)雜、占地面積大、啟動時(shí)間長。2、焦?fàn)t煤氣用于燃?xì)廨啓C(jī)發(fā)電

　　Steam power generation consists of a boiler condensing gas turbine generator. This process uses coke oven gas as a heat source to burn boilers and generate high-pressure steam, which is used to drive steam turbines and generators to generate electricity. Steam power generation technology is mature and reliable. It is widely used in China's coking industry, but its system is complex, occupies a large area, and has a long start-up time. 2. Coke oven gas used for gas turbine power generation

　　燃?xì)廨啓C(jī)發(fā)電是用焦?fàn)t煤氣直接燃燒，驅(qū)動燃?xì)廨啓C(jī)以帶動發(fā)電機(jī)發(fā)電。燃?xì)廨啓C(jī)發(fā)電機(jī)組設(shè)備緊湊、占地少、效率高、效益好、啟動速度快。不過，燃?xì)廨啓C(jī)運(yùn)行一段時(shí)間后必須遠(yuǎn)距離運(yùn)回制造廠檢修，因此需要較多的備品，要求工人有較高的技術(shù)素質(zhì)。3、燃?xì)狻羝?lián)合循環(huán)發(fā)電技術(shù)（CCPP）

　　Gas turbine power generation is achieved by directly burning coke oven gas to drive the gas turbine, which in turn drives the generator to generate electricity. The gas turbine generator set is compact, occupies less land, has high efficiency, good benefits, and fast starting speed. However, after running for a period of time, gas turbines must be transported back to the manufacturing plant for maintenance at a long distance, requiring a large number of spare parts and requiring workers to have high technical skills. 3. Gas Steam Combined Cycle Power Generation Technology (CCPP)

　　該技術(shù)的基本原理是將剩余的焦?fàn)t煤氣和回收的高爐煤氣經(jīng)凈化、混合、加壓后送往燃?xì)廨啓C(jī)燃燒、膨脹做功，帶動燃?xì)廨啺l(fā)電機(jī)組發(fā)電。同時(shí)燃?xì)廨啓C(jī)排放的高溫?zé)煔饧訜嵊酂徨仩t，產(chǎn)生蒸汽，帶動蒸汽輪發(fā)電機(jī)組，形成聯(lián)合循環(huán)發(fā)電。燃?xì)狻羝?lián)合發(fā)電是熱能資源的高效梯級綜合利用，其發(fā)電效率高達(dá)45％以上，實(shí)現(xiàn)了鋼電聯(lián)產(chǎn)，目前我國的濟(jì)鋼、寶鋼、太鋼、沙鋼、通鋼、鞍鋼、馬鋼、邯鋼安鋼、漣鋼等多家鋼廠都在使用該技術(shù)。4、用煤氣內(nèi)燃機(jī)帶動發(fā)電機(jī)發(fā)電

　　The basic principle of this technology is to purify, mix, and pressurize the remaining coke oven gas and recovered blast furnace gas before sending them to a gas turbine for combustion, expansion, and power generation, driving the gas turbine generator set to generate electricity. At the same time, the high-temperature flue gas emitted by the gas turbine heats the waste heat boiler, generates steam, and drives the steam turbine generator unit to form a combined cycle power generation. Gas steam combined power generation is an efficient cascade comprehensive utilization of thermal energy resources, with a power generation efficiency of over 45%, realizing the co production of steel and electricity. Currently, many steel mills in China, such as Jigang, Baosteel, Taiyuan Iron and Steel, Shagang, Tonggang, Ansteel, Magang, Handan Iron and Steel, and Lianyungang, are using this technology. 4. Using a gas internal combustion engine to drive a generator to generate electricity

　　我國山東、山西、寧夏、安微、河北、新疆、內(nèi)蒙古、云南、江蘇等地的一些焦化廠采用煤氣內(nèi)燃機(jī)發(fā)電?？晒┻x擇的焦?fàn)t煤氣內(nèi)燃機(jī)發(fā)電機(jī)組有400千瓦、500千瓦、1200千瓦和2000年瓦。目前焦化行業(yè)大多采用的是500千瓦焦?fàn)t煤氣內(nèi)燃機(jī)發(fā)電機(jī)組。按焦?fàn)t煤氣熱值（低熱值）16720千焦/立方米計(jì)算，1立方米焦?fàn)t煤氣可發(fā)電1.1千瓦時(shí)。

　　Some coking plants in Shandong, Shanxi, Ningxia, Anhui, Hebei, Xinjiang, Inner Mongolia, Yunnan, Jiangsu and other places in China use gas internal combustion engines to generate electricity. The available options for coke oven gas internal combustion engine generator sets are 400 kW, 500 kW, 1200 kW, and 2000 kW. At present, the coking industry mostly uses 500 kW coke oven gas internal combustion engine generator sets. According to the calorific value (low calorific value) of 16720 kilojoules per cubic meter of coke oven gas, 1 cubic meter of coke oven gas can generate 1.1 kilowatt hours of electricity.

　　三、利用焦?fàn)t煤氣制氫焦?fàn)t煤氣中的氫含量達(dá)55％~60％，是重要的氫資源提供者。目前，焦?fàn)t煤氣制氫的主要方法是采用變壓吸附技術(shù)（PSA）從冷焦?fàn)t煤氣中分離氫氣，該工藝生產(chǎn)的氫氣純度可達(dá)99.99％，從上世紀(jì)80年代開始，我國寶鋼、鞍鋼、武鋼、本鋼、包鋼等鋼鐵企業(yè)先后建設(shè)了多套100立方米/時(shí)至5000立方米/時(shí)、純度為99.999％的焦?fàn)t煤氣變壓吸附制氫裝置，其中投產(chǎn)運(yùn)行時(shí)間最長的一套已達(dá)20多年。我國有多家鋼鐵企業(yè)采用PSA從焦?fàn)t煤氣中分離氫氣，用作軋鋼廠保護(hù)性氣體。

　　3、 The use of coke oven gas for hydrogen production has a hydrogen content of 55% to 60%, making it an important hydrogen resource provider. At present, the main method for hydrogen production from coke oven gas is to use pressure swing adsorption (PSA) technology to separate hydrogen from cold coke oven gas. The purity of hydrogen produced by this process can reach 99.99%. Since the 1980s, China's steel enterprises such as Baosteel, Ansteel, Wugang, Benxi Iron and Steel, and Baosteel have successively built multiple sets of coke oven gas PSA hydrogen production units with a purity of 99.999%, ranging from 100 cubic meters/hour to 5000 cubic meters/hour. Among them, the longest operating set has been in operation for more than 20 years. Several steel companies in China use PSA to separate hydrogen from coke oven gas for use as a protective gas in steel mills.

　　據(jù)了解，日本鋼鐵行業(yè)每年提供約40億標(biāo)準(zhǔn)立方米氫氣供應(yīng)給燃料電池行業(yè)使用，通過改進(jìn)工藝，未來其供應(yīng)量將進(jìn)一步增加。另外，由于大多數(shù)日本鋼廠位于城市中心附近，所以未來城市所需的大部分清潔能源可由鋼廠負(fù)責(zé)供應(yīng)。在我國，隨著氫電池開發(fā)、應(yīng)用成本的降低，利用煉焦煤氣提氫將成為焦?fàn)t煤氣資源化利用的新亮點(diǎn)。采用煉焦煤氣生產(chǎn)氫氣將是未來煉焦煤氣資源化應(yīng)用的新途徑。

　　It is reported that the Japanese steel industry provides approximately 4 billion standard cubic meters of hydrogen gas annually for use in the fuel cell industry, and through improved processes, its supply will further increase in the future. In addition, as most Japanese steel mills are located near urban centers, most of the clean energy needed for cities in the future can be supplied by steel mills. In China, with the reduction of development and application costs of hydrogen batteries, utilizing coking gas to extract hydrogen will become a new highlight in the resource utilization of coke oven gas. The use of coking gas to produce hydrogen will be a new approach for the future resource utilization of coking gas.

　　四、焦?fàn)t煤氣用于生產(chǎn)直接還原鐵傳統(tǒng)的煉鐵工業(yè)完全依靠碳為還原劑，隨著煉焦煤和焦炭資源的日益短缺，業(yè)界正在開發(fā)資源節(jié)約、環(huán)境友好的氫冶金，用焦?fàn)t煤氣直接還原鐵是氫冶金重要的應(yīng)用技術(shù)之一。由于氫的還原潛能是一氧化碳的14倍，大力開發(fā)焦?fàn)t煤氣直接還原鐵，可以大大降低煉鐵過程對煉焦煤和焦炭的消耗。直接還原鐵生產(chǎn)技術(shù)的關(guān)鍵在于還原性氣體（70％H2和30％C0）的制備，而焦?fàn)t煤氣中H2和甲烷含量分別在55％~60％和23％~27％，只需將焦?fàn)t煤氣中的甲烷進(jìn)行裂解（重整）即可獲得74％的H2和25％的CO，以此作為直接還原生產(chǎn)海錦鐵的還原性氣體非常廉價(jià)。

　　4、 The traditional ironmaking industry relies entirely on carbon as a reducing agent for the production of direct reduced iron using coke oven gas. With the increasing shortage of coking coal and coke resources, the industry is developing resource efficient and environmentally friendly hydrogen metallurgy. The direct reduction of iron using coke oven gas is one of the important application technologies in hydrogen metallurgy. Due to the fact that the reduction potential of hydrogen is 14 times that of carbon monoxide, vigorously developing direct reduction of iron from coke oven gas can greatly reduce the consumption of coking coal and coke in the ironmaking process. The key to direct reduction of iron production technology lies in the preparation of reducing gases (70% H2 and 30% C0), and the H2 and methane contents in coke oven gas are 55%~60% and 23%~27%, respectively. By cracking (reforming) the methane in coke oven gas, 74% H2 and 25% CO can be obtained, which is a very cheap reducing gas for direct reduction of Haijin iron production.

　　用焦?fàn)t煤氣生產(chǎn)直接還原鐵的研究以HYL-ZR（自重整）希爾工藝技術(shù)為基礎(chǔ)，其通過在自身還原段中生成還原氣體而實(shí)現(xiàn)最佳的還原效率，因此，該工藝無需使用外部重整爐設(shè)備或者其他的還原氣體生成系統(tǒng)。采用HYL-ZR（自重整）希爾工藝用焦?fàn)t煤氣生產(chǎn)直接還原鐵的生產(chǎn)成本較低，直接還原鐵的金屬率可達(dá)94%。

　　The research on the production of direct reduced iron using coke oven gas is based on the HYL-ZR (self reforming) Hill process technology, which achieves optimal reduction efficiency by generating reducing gas in its own reduction section. Therefore, this process does not require the use of external reforming furnace equipment or other reducing gas generation systems. The production cost of direct reduced iron using the HYL-ZR (self weight leveling) Hill process and coke oven gas is relatively low, and the metal yield of direct reduced iron can reach 94%.

　　五、焦?fàn)t煤氣用于高爐噴吹煉鐵高爐噴吹含氫介質(zhì)強(qiáng)化氫還原已成為當(dāng)今冶煉工藝的熱點(diǎn)。首先，無論從熱力學(xué)還是從動カ學(xué)條件看，高溫下氫作為鐵氧化物的還原劑比一氧化碳更具優(yōu)勢；其次，氫還原的氣態(tài)產(chǎn)物是水蒸氣而不是二氧化碳，故噴吹含氫介質(zhì)可減少二氧化碳的產(chǎn)生量。煉焦過程中，煤炭72％~78％生成焦炭，15％~18％生成焦?fàn)t煤氣。在煉鐵過程中，焦炭的還原當(dāng)量與焦?fàn)t煤氣的還原當(dāng)量之比為1：1，因?yàn)镠2的還原潛能與CO的還原潛能之比為14：1。因此，將焦?fàn)t煤氣通入高爐中同樣可以煉鐵，相當(dāng)于提高了煉焦煤資源的利用率，可緩解煉焦煤資源供應(yīng)緊張的問題。

　　5、 The use of coke oven gas for blast furnace injection of ironmaking has become a hot topic in current smelting processes, as it enhances hydrogen reduction by injecting hydrogen containing media into blast furnaces. Firstly, both thermodynamically and kinetically, hydrogen has more advantages as a reducing agent for iron oxides than carbon monoxide at high temperatures; Secondly, the gaseous product of hydrogen reduction is water vapor rather than carbon dioxide, so injecting a hydrogen containing medium can reduce the amount of carbon dioxide produced. During coking, 72%~78% of coal generates coke, and 15%~18% generates coke oven gas. In the ironmaking process, the ratio of the reduction equivalent of coke to the reduction equivalent of coke oven gas is 1:1, because the ratio of the reduction potential of H2 to that of CO is 14:1. Therefore, introducing coke oven gas into the blast furnace can also make iron, which is equivalent to improving the utilization rate of coking coal resources and alleviating the problem of tight supply of coking coal resources.

　　與天然氣相比，焦?fàn)t煤氣的還原性能更好。法國、俄羅斯等國已把高爐噴吹焦?fàn)t煤氣作為節(jié)能減排關(guān)鍵技術(shù)進(jìn)行開發(fā)，目前我國也已開始了高爐噴吹焦?fàn)t煤氣的研究，鋼鐵聯(lián)合企業(yè)的焦化廠應(yīng)關(guān)注該技術(shù)的發(fā)展。

　　Compared with natural gas, coke oven gas has better reducing performance. France, Russia and other countries have developed the injection of coke oven gas into blast furnaces as a key technology for energy conservation and emission reduction. Currently, China has also begun research on the injection of coke oven gas into blast furnaces. Coking plants in steel joint ventures should pay attention to the development of this technology.

　　六、焦?fàn)t煤氣作為化工原料生產(chǎn)合成氣近年來隨著科技的進(jìn)步與廣大企業(yè)的勇于探素，焦?fàn)t煤氣的應(yīng)用領(lǐng)域拓展到制化肥、甲醇-二甲醚、提取甲烷制LNG和合成甲烷等。1、焦?fàn)t煤氣制合成氨——尿素

　　6、 In recent years, with the advancement of technology and the daring exploration of enterprises, the application fields of coke oven gas as a chemical raw material for the production of synthetic gas have expanded to include the production of fertilizers, methanol dimethyl ether, methane extraction to produce LNG, and the synthesis of methane. 1. Ammonia synthesis from coke oven gas - urea

　　早在20世紀(jì)60年代，我國本溪鋼鐵公司第二焦化廠率先開發(fā)了焦?fàn)t煤氣熱裂解技術(shù)用于制純氫，與空分氮?dú)夂铣砂?，進(jìn)而生產(chǎn)尿素。2、焦?fàn)t煤氣生產(chǎn)甲醇

　　As early as the 1960s, the Second Coking Plant of Benxi Iron and Steel Company in China took the lead in developing coke oven gas pyrolysis technology for producing pure hydrogen, synthesizing ammonia with air separation nitrogen, and then producing urea. 2. Production of methanol from coke oven gas

　　每生產(chǎn)1噸甲醇可消耗焦?fàn)t煤氣2000立方米～2200立方米，對富余的煉焦煤氣消費(fèi)非?？捎^。以焦?fàn)t煤氣生產(chǎn)甲醇500萬噸計(jì)算，就可以消耗焦?fàn)t煤氣100億～120億立方米。因此，利用焦?fàn)t煤氣制甲醇、二甲醒、人造汽油等資源化開發(fā)利用比作為燃料具有更大的經(jīng)濟(jì)和社會效益。為推進(jìn)甲醇燃料的應(yīng)用，國家先后出臺了M15、M85等甲醇汽油標(biāo)準(zhǔn)，山西、陜西、河南等地已經(jīng)開始甲醇汽油的車用試點(diǎn)。

　　Producing 1 ton of methanol can consume 2000 cubic meters to 2200 cubic meters of coke oven gas, which is a considerable amount of surplus coke oven gas consumption. Calculating based on the production of 5 million tons of methanol from coke oven gas, 10 billion to 12 billion cubic meters of coke oven gas can be consumed. Therefore, the resource utilization of coke oven gas to produce methanol, dimethyl ether, and synthetic gasoline has greater economic and social benefits than using it as fuel. To promote the application of methanol fuel, the country has successively issued standards for methanol gasoline such as M15 and M85, and pilot projects for methanol gasoline for vehicles have begun in Shanxi, Shaanxi, Henan and other places.

　　3、焦?fàn)t煤氣提取或合成天然氣

　　3. Extraction or synthesis of natural gas from coke oven gas

　　在焦?fàn)t氣組成中，甲烷含量約23％～27％，一氧化碳和二氧化碳含量占近10％，其余為氫和少量氮，因此焦?fàn)t氣通過甲烷化反應(yīng)，可以使絕大部分一氧化碳和二氧化碳轉(zhuǎn)化成甲烷，得到主要含氫、甲烷、氮的混合氣體，經(jīng)進(jìn)一步分離提純后可以得到甲烷體積在90％以上的合成天然氣（SNG），再經(jīng)壓縮得到壓縮天然氣（CNG）或經(jīng)液化得到液化天然氣（LNG）。焦?fàn)t煤氣深度凈化后經(jīng)甲烷化生產(chǎn)天然氣（SNG/CNG/LNG）的技術(shù)，具有投資小、消耗低、無污染、能量利用率高等優(yōu)勢，是焦化企業(yè)較佳的選擇。

　　In the composition of coke oven gas, methane content is about 23% to 27%, carbon monoxide and carbon dioxide content accounts for nearly 10%, and the rest is hydrogen and a small amount of nitrogen. Therefore, coke oven gas can be converted into methane through methane reaction, obtaining a mixed gas mainly containing hydrogen, methane, and nitrogen. After further separation and purification, synthetic natural gas (SNG) with a methane volume of over 90% can be obtained, which can then be compressed to obtain compressed natural gas (CNG) or liquefied to obtain liquefied natural gas (LNG). The technology of deep purification of coke oven gas and methane production of natural gas (SNG/CNG/LNG) has the advantages of low investment, low consumption, no pollution, and high energy utilization rate, making it a better choice for coking enterprises.

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