煤气化发电与电解水制氢联产干冰工艺路线设想

Some Ideas on Route of Combined Coal Gasification Power Generation,Water-electrolytic Hydrogen Making and Dry Ice Production

推荐煤气化发电与电解水制氢联产干冰的工艺路线。该工艺以煤炭、空气和水为原料,干粉煤纯氧高温(1700℃)气化全部转化成合成气(CO+H_2),用脱硫后的纯合成气CO含63%以上的部分合成气作电解水制氢的循环介质,可使制氢的电耗由4.76k W·h/m^3 H_2(标准状态)降到1.67k W·h/m3 H_2(标准状态)。同时CO在水电解阳极同水中的氧变换成CO_2(或CO_2+O_2)。阳极排出的CO_2浓度可调节成79%CO_2+21%O_2,用于燃气轮机发电助燃剂,排出的烟气为高温纯CO_2,进入废锅产高压蒸汽用于发电后经冷却节流膨胀成雪花状固体CO_2干冰,可用作植物肥料。水电解阴极取得纯H_2产品,可用于合成气中配H_2,用于合成甲醇。于是电解水槽成为用电能分解水和合成气用于发电和生产化工产品原料气的转化调节核心装置,其调整负荷控制在40%以内,成为调节电力与化工产品生产的经济可行的创新技术。

This article presents a technical route for combined coal gasification power generation,water-electrolytic hydrogen making and dry ice production.The technology uses coal,air and water as raw materials.Dry powdered coal is gasified under high temperature（1700 ℃） and pure oxygen conditions and fully converted to syngas（CO ＋H_2）.When part of the pure desulfurized syngas,the CO content of which is higher than 63%,is used as the circulating medium in the process of making hydrogen from electrolyzed water,the power consumption in hydrogen production can drop to 1.67 k W·h/m3H_2（in standard state） from 4.76 k W·h/m^3 H_2（in standard state）.At the same time,CO reacts with the oxygen in the water at the water electrolysis anode and is converted to CO_2（or CO_2＋O_2）.The concentration of CO_2 from the anode can be adjusted to 79%CO_2＋21%O_2（used as a combustion improver in gas turbine power generation）.The flue gas emitted is high-temperature pure CO_2 and enters a waste heat furnace to produce high-pressure steam for use in power generation.The CO_2 is then cooled down and converted to snowflake-like solid-CO_2 dry ice-through throttling expansion,which can be used as a fertilizer for plants.Pure H_2 is obtained at the water electrolysis cathode and can be used in syngas to make methanol.Therefore,the electrolytic tank is the core conversion and regulation unit in the processes of using power to decompose water and syngas to generate power and produce chemical prod-uct feedstock gas.Its regulating load is maintained under 40%.This is an economic and feasible innovative technology for regulating power and chemical product production.