加压固定床粗煤气再转化工艺研究

通过理论分析,综合加压固定床煤气化工艺和烃类转化工艺的技术特点,提出加压固定床粗煤气再转化工艺。加压固定床粗煤气再转化工艺取消了现有加压固定床煤气化工艺中煤气水分离、酚氨回收、废气焚烧、变换工艺洗涤塔、低温甲醇洗工艺萃取系统和石脑油分离系统等装置,降低固定资产投资46.9亿元（现用煤气化工艺化工固定资产投资117.25亿元）;每年减少使用原料煤96.84万～118.18万t,约合1.29亿元（以褐煤120元/t计）;取消使用二异丙基醚0.21万t/a、减少甲醇用量0.96万t/a和质量分数32%的NaOH用量0.36万t/a;取消含尘煤气水和含油煤气水排放量1585.71 t/h（原排放污水1761.9 t/h）;减少废水处理装置土地使用面积17790 m2以上。提高CO2利用率,提高硫回收率。加压固定床粗煤气再转化工艺具有工艺、设备和工程建设投资少,工艺运行成本低,环境保护好等显著特点。

Research on reconversion process of pressurized fixed-bed raw coal gas

Combining the technical characteristics of pressurized fixed-bed gasification process and hydrocarbon conversion process,put forward the reconversion process of pressurized fixed-bed raw coal gas through theoretical analysis.The coal gas water separation,phenolic ammonia recovery,flue gas burner,conversion scrubber,devices in low-temperature methanol washing system and naphtha separation system and so on have been abandoned thanks to the new technology.This technology reduces the fixed asset investment by 4.69 billion yuan annually（while the present technical process costs 11.725 billion annually）,saves raw coal by 0.9684 million to 1.1818 million tons annually,approximate to 129 million yuan when the price of lignite is 120 yuan per ton,saves DIPE by 2100 tons,lowers methonal consumption by 9600 tons and sodium hydroxide which mass fraction is 32% by 3600 tons;decreases the dusty gas water and oil gas water emission by 1585.71 t/h while it uesd to pour sewage 1761.9 t/h,lessens the land area taken by wastewater treatment plant over 17790 m2.It also improves the utilization rate of carbon dioxide and the recovery of sulfur.This reconversion process need less investment in equipments and engineering construction as well as low operating cost and environmentally friendly.