Reactivation of waste active carbons in gas-production industry

The efficiency of desulphurization of natural gas is largely determined by the purity of the used amine solvents. The removal from these solutions of high molecular weight impurities is entirely dependent on the quality of active carbon (AC) used for cleaning. On the other hand, AC wastes are disposed in damps, which deteriorates both the economy ofthe desulfurization process and creates the problems of pollution of the lithosphere. The authors conducted the evaluation of new high-strength AC for cleaning amine solutions and developed a technology forcoal reactivation, allowing its repeated use in this technology.
Materials and methods
For this work was used amine solution of desulfurization unit Orenburg GPP. Laboratoryabsorption unit for purification spent amine solutions with active carbon was designed. Pilot electric furnace with rotating retort diameter of 52 mm for the reactivation process was designed and built.
Results
This study showed that spent active carbon can be reactivated and restore its adsorption properties and re-used effectively. In addition, an important environmental problem is solved for the prevention of pollution of the lithosphere from toxic solid waste of spent carbon.
Сonclusions
The performed tests showed next:
1. Thermal steam activation allows completely restore the porous structure of adsorption carbons used for amine solutionstreatment. Also thermal steam activation allows keeping stable adsorption capacity at level 91-96% of origin active carbon capacity.
2. Minimum strength loss from attrition (1,0-1,5%) and high output of re-activated product at level 98% proved the economic efficiency of reactivation process.
3. The new domestic extra-strong active carbon branded FAS-3 with advanced structure of sorbtion porous spaces does not lose its operation properties before foreign Norit RB-2. At some points the FAS- 3 surpass Norit RB-2 and was significantly better than active carbon branded AG-3.