OCR Text |
Show • Longer refractory life • Reduced size and capital cost • Reduced operating cost. The cyclonic combustion system is capable of incinerating a wide variety of solid, liquid, and gaseous wastes and offers great operational flexibility. Three pilot-scale test programs involving cyclonic incineration have amply demonstrated its capability: • • • A low-Btu gaseous waste (55 to 65 Btu/SCF) from an industrial process using H2 , CO, CH4 , and NH~ was combusted.[9] Combustion was stable at 1900 F (achieved through air and waste preheat), NH3 conversion to NOx was as low as 5% (the NO level with no NH3 in feed was below 10 ppm), and CO levels were in the ran~e of 25 to 30 ppm. The test unit was operated at a 3 X 10 Btu/h rate; no supplemental fuel was required because of the intense mixing that occurs in the cyclonic incinerator. Carbon tetrachloride was destroyed as a surrogate ~or PCB's at a combustion rate of approximately 1 X 10 Btu/ h. In a two-phase program, the carbon tetrachloride was processed at both high and low concentrations. Three nonhazardous wastewaters from a typical foo% process were successfully incinerated in a 1 X 10 Btu/h pilot-~cale unit; one of these was also incinerated on a 3 X 10 Btu/h demonstration system.[lO,ll] This wastewater was a solution of 25% to 45% organic material and 5% to 20% inorganic material in water. The waste was incinerated with supplemental natural gas fuel at temperatures of about 20000F in the dry-ash mode. Combustion was stable and complete, with less than 100 ppm CO in the exhaust. Table 4 summarizes the results obtained in the cyclonic combustion/incineration testing programs. The details of these studies are provided by Khinkis.[12] In addition, IGT has recently been awarded a contract from a consortium of companies including GRI, IGT-SMP, gas companies, aluminum producers, and incinerator manufacturers to evaluate the applicability of IGT's natural gas-fired cyclonic incinerator to industrial waste incineration with molten (benign) ash discharge, using spent aluminum potliners as an example. In this application, the incinerator, with the addition of various fluxing agents, will operate in a slagging mode. The vitreous slag will render the inorganic constituents that cannot be destroyed into a non-leachable form capable of being landfilled without special precautions. -14- INSTITUTE o F GAS TEe H N 0 LOG Y |