【摘要】：煤炭直接液化技術(shù)是煤轉(zhuǎn)化獲取燃料和化學(xué)品的有效途徑之一,該技術(shù)面臨兩種選擇——以產(chǎn)品為導(dǎo)向的石油替代燃料和以原料為導(dǎo)向的煤基化學(xué)品及燃料。前者需加氫精制提高液化產(chǎn)物氫碳比、加氫裂解開環(huán),增加烷烴比例以提高辛烷值/十六烷值,同時降低雜原子含量,能耗和氫耗大,產(chǎn)品價格容易受石油價格沖擊;后者需經(jīng)多步分離/精制,提高產(chǎn)品的純度和產(chǎn)率,雖然產(chǎn)品的價值很高,但同樣需要大量的能耗和物耗。因此,建立并比較煤直接液化系統(tǒng)兩種不同選擇下的工藝單元對煤直接液化技術(shù)的選擇有重要的參考價值。本文以煤炭科學(xué)研究總院日本NEDOL模式0.1 t/d煤直接液化連續(xù)試驗數(shù)據(jù)為基礎(chǔ),首先從物料衡算及能量衡算角度分析建立煤直接液化流程模擬的可行性,其次以Aspen Plus為平臺分別對以勝利褐煤和神華煤為原料的煤直接液化工藝中的煤干燥單元、加氫液化反應(yīng)單元以及反應(yīng)產(chǎn)物氣固液分離單元進(jìn)行模擬計算,在流程建立的過程中,分別用模型化合物及虛擬組分表示液化油,并以液化油為中心物質(zhì),對流程中的物性參數(shù)進(jìn)行補(bǔ)充以完善流程的模擬,同時以三甘醇萃取精餾提酚、環(huán)丁砜液液萃取芳香烴,對液化油180-200℃餾分段進(jìn)行酚-芳烴-烷烴族組分分離研究,得到的主要結(jié)果和結(jié)論如下:1.溫和工藝與傳統(tǒng)工藝相比,由于溫度、壓力均下降,導(dǎo)致煤轉(zhuǎn)化率降低,蒸餾油中重質(zhì)組分增加,雖然在液化單元能耗降低,但分離過程中重質(zhì)油分離難度增加,從而導(dǎo)致分離單元能耗增加。2.神華煤直接液化油品以虛擬組分為模型,以高低溫及減壓蒸餾進(jìn)行分離,在能耗分布上,分離可充分利用液化產(chǎn)物對于溫度壓力表現(xiàn)的不同,從而利用前期投入的能量,避免冷態(tài)分離下的能耗損失。3.神華煤加氫液化反應(yīng)熱效應(yīng)與文獻(xiàn)值接近,而勝利煤加氫液化熱效應(yīng)放熱較大,這與勝利褐煤的煤階低,反應(yīng)活性高有關(guān)。4.以模型化合物代替液化油,所選模型化合物保留煤液化油的基本共沸,可以用于液化油分離的模擬,熱力學(xué)模型選擇UNIF-LBY。5.三甘醇-環(huán)丁砜組合溶劑可以實現(xiàn)煤液化油窄餾分中酚-芳烴-烷烴的分離,溶劑易于分離回收,以180-200℃窄餾分液化油模擬,酚的提取率達(dá)99.23 wt%,純度為95.75 wt%,得到含芳烴18.85 wt%的航空燃料,以及純度為79.94 wt%的芳烴,并且兩種溶劑的回收率均在98%以上。
[Abstract]:Direct coal liquefaction technology is one of the effective ways for coal conversion to obtain fuel and chemicals. This technology faces two kinds of choices: product-oriented petroleum alternative fuel and feedstock oriented coal-based chemicals and fuels. The former needs to improve hydrogen-carbon ratio of liquefaction product, open ring by hydrocracking, increase alkane ratio to increase octane number / cetane number, decrease hetero-atom content, energy consumption and hydrogen consumption are large, product price is vulnerable to oil price shock. The latter needs to be separated / refined by many steps to improve the purity and yield of the product. Although the value of the product is very high, it also needs a lot of energy consumption and material consumption. Therefore, the establishment and comparison of the process units under two different choices of direct coal liquefaction system has important reference value for the selection of direct coal liquefaction technology. Based on the continuous test data of direct coal liquefaction of NEDOL model 0.1 t / d in Japan, this paper first analyzes the feasibility of establishing direct liquefaction flow simulation of coal from the angles of material balance and energy balance. Secondly, the coal drying unit, hydrogenation liquefaction reaction unit and gas-solid-liquid separation unit of reaction products are simulated and calculated by using Aspen Plus as the platform, respectively, in the process of establishing the process, using Shengli lignite and Shenhua coal as raw materials, respectively, in the process of direct coal liquefaction, the hydroliquefaction reaction unit and the gas-solid-liquid separation unit of reaction products are simulated and calculated. The model compound and virtual component were used to represent the liquefied oil, and the liquefaction oil was taken as the central substance to supplement the physical parameters of the process to improve the simulation of the process. Meanwhile, triethylene glycol was used to extract distilled phenol and sulfolane solution to extract aromatics. The separation of phenol-aromatics and alkanes in the 180-200 鈩，

本文編號：2274810