Removal of Gaseous Alkali Metal Compounds from Hot Flue Gas by Particulate Sorbents

Abstract

Six commercially available materials have been tested as granular sorbents to be used in granular-bed filters for the removal of gaseous alkali metal compounds from the hot (1073 to 1153 K) flue gas of pressurized fluidized-bed combustors (PFBC) for proposed combined-cycle power generation. Tests were performed using a simulated dry flue gas of PFBC in a laboratory-scale, fixed-bed combustor. Diatomaceous earth and activated bauxite were found to be the two most promising sorbents. The experimental results of screening tests are presented, along with the effects of temperature and superficial velocity and space velocity of the flue gas on the sorption performance for the two sorbents. Possible sorption mechanisms, applications of the sorbents and preliminary cost evaluations are discussed.

Moving-bed, granular-bed filter development program option III: Development of moving-bed filter technology for multi-contaminant control task 14: Test plan. Topical report

“…Activated bauxite and diatomaceous earth have been reported to effectively capture NaCI, KCI, and K2S0, (Lee and Johnson, 1980). One set of sorbent screening experiments found diatomaceous earth, attapulgus clay, and activated bauxite to be the most effective for removal of alkali (Jain and Young, 1985).…”

“…Of these alkali sorbents tested, bauxite was reported to be fractionally irreversible with alkali removal being 10% chemical sorption and 90% physically absorbed as watersoluble alkali (Lee and Johnson, 1980) while the clay sorbents react irreversibly with alkali (Bachovchin, 1986;Uberoi, 1990;McLaughlin, 1990). Activated bauxite is a relatively expensive sorbent which would not be suitable as a non-regenerable sorbent.…”

Simultaneous high-temperature removal of alkali and particulates in a pressurized gasification system. Final technical progress report, April 1981-July 1983

“…--= 0 eff (35) Since the length of the average pore is much smaller than the sample (38) Again, for the GE data, the obse-rved rate of reaction given in Table 69 must be multiplied by about 0.58-to get it in terms of unit volume of bulk sample. The ratio of observed reaction rate to pore.…”

The Characteristics of Combustion and Dynamic Analysis of Mixed Zhundong Coal and Oil Shale Semi-coke

“…In response to these problems Zhundong coal, domestic and foreign research and development of a number of additives to control the behavior of alkali metals, such as kaolin clay minerals which are the most common [7,8], Currently burning Zhundong coal power plants are also used kaolin boiler contamination prevention. Kaolin is an inexpensive and easy to add additive, Can adsorb the flue gas in the gas phase containing alkali metal components and reaction to produce aluminosilicate [9], Significantly reduce the pollution of the boiler heating surface and particulate matter emissions [10].…”