摘要:

AbstractBench scale studies of the reaction between sulfur dioxide and alkaline sorbents were performed in an integrated fixed bed reactor at low temperature, simulating the fabric filter dust layer of dry FGD systems with SO2laden gas passing through it. Three major groups of sorbent were tested: calcitic and dolomitic hydrated lime, sodium bicarbonate, and limestone (calcite aragonite) with salt additives such as CaCl2, Ca(NO3)2, and NaNO3. Relative humidity significantly affected SO2absorption by lime and limestone plus additives, but had less impact on NaHCO3reactivity. Different reaction patterns for various sorbents were observed: the SO2/hydrated lime reaction rate was reduced with conversion of the sorbent, resulting in limited lime utilization, whereas the reactions between SO2and NaHCO3and SO2and CaCO3plus additives seem to proceed a constant rate, potentially leading to high sorbent utilizations. Results are discussed relating to sorbent screening for dry FGD systems.

ISSN:0278-4491    

DOI:10.1002/ep.670060120

出版商:American Institute of Chemical Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractIt has been demonstrated in this laboratory that specific organisms are capable of breaking both o/w and w/o petroleum derived emulsions. Specific bacteria have been selected and have been tested on model (kerosene/water) and on complex field emulsions obtained during enhanced oil recovery trials (w/o) and in tar sands extraction process (o/w).More recent studies involve the use of microbial biomass (sludge) from municipal and refinery waste water treatment processes as the de‐emulsifying agents for treatment of these emulsions.The results indicate that either pure microbial cultures or microbial waste biomass can be used to efficiently break industrial emulsions. This approach is a novel application and is a promising alternative to use of chemically synthesized industrial de‐emulsifying age

ISSN:0278-4491    

DOI:10.1002/ep.670060121

出版商:American Institute of Chemical Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractCECOS International, Inc., a hazardous waste treatment and disposal firm headquartered in Buffalo, New York, and MODAR, Inc. of Houston, Texas, conducted a field, pilot‐scale demonstration of the MODAR Oxidation Process for the destruction of hazardous organic waste materials in 1985.The MODAR Oxidation Process utilizes water at conditions above its critical point (647K and 22.1 MPa) as the reaction medium for the oxidation of organic materials. The products of this oxidation reaction, for a typical organic material, are carbon dioxide and water. Any halogen present as part of the organic matrix is converted to its halo‐acid form. Two waste streams were destroyed in the field tests. These were an aqueous‐based waste contaminated with several organic EPA priority pollutants, and an organic transformer dielectric fluid contaminated with polychlorinated biphenyls (PCBs). In both tests, water constituent concentrations in liquid and gas process effluents were below analytical detection limits. Destruction efficiencies based on influent concentrations and the reported detection limits were greater than “four nines”. The results of the demonstration have shown the process' ability to destroy toxic and persistent organic contaminants in liquid wastestreams without producing hazardous by

ISSN:0278-4491    

DOI:10.1002/ep.670060122

出版商:American Institute of Chemical Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractThe Fluidized‐Bed Copper Oxide Process is a regenerative process for the simultaneous removal of both sulfur dioxide (SO2) and nitrogen oxides (NOX) from the flue gas of coal‐fired boilers. An ideal‐flow reactor model for SO2removal was formulated based on a sulfation reaction kinetics model developed using data from a microbalance reactor. Experimental data obtained from a fluidized‐bed reactor having a cross section measuring 1.02 m by 1.22 m (40 in. by 48 in.) were used to validate the model. The variables in the model were systematically varied to predict reactor performance under different operating conditions. The process variables studies were (1) sorbent copper content, (2) reactor bed depth, and (3) reaction temperature. The reactor performance predictions showed that increasing the copper content of the sorbent from 5 percent to 7 percent would lower the required sorbent recirculation rate by 30 percent. The expanded‐bed depth in the reactor was also an important parameter. Effective performance of the process can be obtained with lower sorbent recirculation rates if the expanded‐bed depth in the reactor i

ISSN:0278-4491    

DOI:10.1002/ep.670060123

出版商:American Institute of Chemical Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractUse of ferrous cysteine additives in flue gas scrubbing systems creates a different and simpler scrubber chemistry compared to Japanese processes using ferrous chelates such as Fe2+(EDTA). Instead of being converted to nitrous oxide, nitric oxide in flue gas can be concentrated and/or reduced to nitrogen gas. Also, production of dithionate ions and nitrogen‐sulfur compounds in scrubbing systems can be avoided. Fixation of nitric oxide occurs by a rapid reaction with the ferrous cysteine complex, at pH between 7.5 and 6.5, to form solid cystinatodinitrosyl iron (II), which releases NO upon heating. Most of the NO is reduced to gaseous species, primarily N2, in ferrous cysteine solutions at pH 10. Cysteine can rapidly reduce ferric ion to ferrous ion while being oxidized to cystine. Cystine can be reduced back to cysteine by SO

ISSN:0278-4491    

DOI:10.1002/ep.670060124

出版商:American Institute of Chemical Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractHazardous waste and the problems associated with its proper disposal are the concerns of the Hazardous Waste Research Center (HWRC), located on the Baton Rouge Campus of Louisiana State University.The Center is a part of the U.S. Environmental Protection Agency's “Centers of Excellence” program to conduct long‐term fundamental research in 3 major areas: (1) incineration/combustion; (2) alternate methods of treatment/destruction; (3) chemicals/materials interaction and stabilization.The projects are interdisciplinary in scope, with faculty members from civil, mechanical, and chemical engineering, chemistry, and the marine sciences participating.Future research directions will change to keep pace with the problems and needs of industry, waste handlers, government, and the public. The Hazardous Waste Research Center, in dealing with current problems and anticipating future needs, will help reduce the risk and/or extent of negative impact on the environment, on human health, or on the economy of the nation due to improper management or disposal of hazardous w

ISSN:0278-4491    

DOI:10.1002/ep.670060125

出版商:American Institute of Chemical Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractContaminated, acidic cooling and gypsum pond waters associated with wet‐process phosphoric acid production can be treated using a partial liming process. The treatment largely removes the fluoride component, giving a treated water which is suitable for use in the phosphate rock wet grinding circuit; a majority of the phosphate component of the pond water is thereby directly recovered.Although the acidity of the contaminated water is only partially neutralized during treatment, phosphate rock added to the grinding mill contains sufficient carbonate to give a ground rock slurry of low corrosivity. This process has been used successfully during the last four years at Agrico Chemical Company's Faustina Plant to manage occasional water balance problems resulting from high rainfal

ISSN:0278-4491    

DOI:10.1002/ep.670060126

出版商:American Institute of Chemical Engineers    

年代:1987

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670060101

出版商:American Institute of Chemical Engineers    

年代:1987

数据来源: WILEY