Abstract |
Gas-liquid chemical absorption reactors were studied for application to the Molten Carbonate process. Exploratory experiments showed that absorption of sulfur dioxide in a eutectic mixture of lithium, potassium, and sodium carbonates is very rapid. A continuous wetted-wall absorber demonstrated that the rate of sulfur dioxide absorption in carbonate is limited by mass transfer in the gas phase. To demonstrate that high efficiency of sulfur dioxide absorption is possible in a continuous reactor, a 2 in. ID column fitted with baffles was assembled. The absorption of nitric oxide (NO) was also tested with the baffle column. Experimental results indicated that nitric oxide reacts slowly in the carbonate melt. Nitric oxide did not significantly alter the absorption of sulfur dioxide. Theoretical analysis of liquid diffusion within droplets gave limits for degree of carbonate reaction in various-sized droplets. Analysis of gas-phase diffusion to an aerosol of droplets revealed that sulfur dioxide absorption occurs principally in the vicinity of the spray nozzle where droplet velocity relative to the gas is highest and droplet velocity relative to the absorber walls is decreasing. The results of experiments and theoretical studies suggest employing a spray reactor for pilot-plant tests. (Author) |