摘要:

AbstractBiocatalytic Desulfurization (BDS) represents an alternative approach to the reduction of sulfur in fossil fuels. The objective is to use bacteria to selectively remove sulfur from petroleum and middle distillate fractions, without the concomitant release of carbon. Recently, bacteria have been developed which have the ability to desulfurize dibenzothiophene (DBT) and other organosulfur molecules. These bacteria are being developed for use in a biocatalyst‐based desulfurization process. Analysis of preliminary conceptual engineering designs has shown that this process has the potential to complement conventional technology as a method to temper the sulfur levels in crude oil, or remove the recalcitrant sulfur in middle distillates to achieve the deep desulfurization mandated by State and Federal regulations.This paper describes the results of initial feasibility studies, sensitivity analyses and conceptual design work. Feasibility studies with various crude oils and middle distillates achieved unoptimized desulfurization levels of 40–80%. Sensitivity analyses indicate that total desulfurization costs of about $3.00 per barrel for crude oil and less than $2.00 per barrel for diesel are possible. Key criteria for commercial success of the process include the cost and half‐life of the biocatalyst, residence time in the reactor, oil/water ratios required to extract the sulfur and the disposition of the separated sulfur pro

ISSN:0278-4491    

DOI:10.1002/ep.670120103

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670120102

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670120114

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractThe results of an initial feasibility study on the bioremediation of sludge are presented. The sludge used in the study was taken from a site containing waste produced during the refining of lubricant oils to which sulfuric acid had been added. The effectiveness of bioremediation was examined using shake flask experiments with indigenous and other bacteria sources and nutrient supplementation. The initial results show limited effectiveness of biological treatment at conditions employing indigenous bacteria and low (2%) sludge concentraticws in Bushnell‐Haas media. In addition, the indigenous bacteria were seen to degrade the polycyclic aromatic hydrocarbons naphthalene, penanthrene and pyrene which are present at some locations at the site. No apparent degradution of material was seen using conditions of high (30%) sludge concentrations in Bushnell‐Haas medium under a variety of conditions. In addition, nutrients were rapidly depleted at these sludge concentrations, with the exception of sulfates which were produced when high sludge concentrations were u

ISSN:0278-4491    

DOI:10.1002/ep.670120104

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670120115

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670120116

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670120118

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670120119

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractThe initial progress of an ongoing laboratory investigation is described in which phenol and aniline were mixed into a slightly organic, loamy soil and various aqueous solutions used to attempt to extract these organic contaminants. Extraction compounds consisted of deionized water, hydrogen peroxide at varying concentration and sodium hydroxide at varying pH. Two methods were used to affect desorption. The first method, which is simple and quick, has been termed the “successive reverse isotherm” (SRI) method, and the second method, which is very labor intensive and time‐consuming, but which represents better the conditions that exist in an in situ extraction operation, was the permeation method. The SRI method indicated that an aqueous solution of hydrogen peroxide in concentration of 200 to 500 mg/L extracted about 45% of the phenol, while an aqueous solution of sodium hydroxide at a pH of 10 extracted in excess of 70% of the phenol. On the other hand, none of the solutions extracted more than 25% of the aniline. Further tests conducted in permeameters indicated that approximately 80% of phenol was recovered by permeation with either hydrogen peroxide or sodium hydroxide and that both were measurably more effective than deionized water. Neither the phenol nor any of the decontaminants had any major effect on hydraulic conductivity or physical index properties of the soil. From the results of the tests to date, the SRI test appears to provide a viable method of predicting whether permeameter tests will yield productive re

ISSN:0278-4491    

DOI:10.1002/ep.670120105

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractA full‐scale RBC plant having two parallel trains and treating combined municipal and industrial dairy waste was used to investigate the effectiveness of supplemental aeration and an enlarged first‐stage in improving RBC performance. Enlarged first‐stage was created by removing the baffles between the first two stages. One RBC train was used as a control and the other train was used to evaluate the combined effectiveness of supplemental aeration and an enlarged first‐stage. Composite wastewater samples were collected from influent and effluent of each RBC stage in both trains. Samples were analyzed for soluble COD and BOD5, ammonia nitrogen, and suspended solids. Wastewater temperature, pH and dissolved oxygen levels were measured in each stage. The study results indicate that it is possible to achieve higher organic loading rates and removal rates when RBC units are provided with supplemental aeration and enlarged firs

ISSN:0278-4491    

DOI:10.1002/ep.670120106

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY