Engineering Commons^™

Wastewater Treatment And Management At Oil Shale Plants, R. E. Hicks, R. F. Probstein, I. Wei, D. S. Farrier, J. Lotwala, T. E. Phillips

Irvine W. Wei

Laboratory tests have shown that the major wastewater streams produced during oil shale retorting can in principle be treated to a quality suitable for reuse within the plant. The wastewater stream condensed from the retort gases, here called the gas condensate, contains primarily dissolved gases (NH3, CO2 and some H2S) and organics as contaminants. In batch stripping tests it was found that the organics, which may be present at concentrations of up to 5,000 mg/l measured as COD, are volatile and can be stripped along with the ammonia down to about 500 mg/l COD. Retort waters, or wastewater streams that …

Dynamics Of Breakpoint Chlorination, Irvine Wei, J. Carrell Morris

Irvine W. Wei

No abstract provided.

Advanced Chemical Oxidation And Toxicity Reduction Of 2,4,6-Trichlorophenol By Using Fenton's Reagent: Part Ii, Dechlorination Kinetics, Somnath Basu, Venkat Sreenivasan, Irvine W. Wei

Irvine W. Wei

Laboratory investigation has shown that Fenton's Reagent is a very effective oxidant for 2,4,6-Trichlorophenol (TCP). The authors reported the first phase of this research, consisting of five different reactions of Fenton's Reagent on TCP, at the 1995 AIChE Summer National Meeting in Boston as Part I of this paper. The results demonstrated total removal of TCP, with almost complete release of aromatic ring bound chlorine atoms into chloride ions, significant reduction of TOC, and very importantly, significant toxicity reduction compared to the original substrate. These results suggested that Fenton's Reaction can be considered as a candidate process for treatment of …

Biological Treatment Of Coal Conversion Condensates, Irvine Wei, D. J. Goldstein

Irvine W. Wei

Biochemical oxidation is an important way to remove organic contamination from foul condensates in coal conversion plants. The design considerations are discussed; oxygen is recommended in preference to air, and a test with mutated bacteria is recommended. Reactor configurations are also discussed. When the organic contamination is high, the use of oxygen requires forced cooling and a combined cooling tower/trickling filter is suggested for test. Preliminary plant designs are given for two situations in a Hygas plant: one when lignite is fed and one when a bituminous coal is fed.

Advanced Chemical Oxidation And Toxicity Reduction Of 2,4,6-Trichlorophenol By Using Fenton's Reagent: Part Iv, Reaction Mechanism And Kinetics, Somnath Basu, Irvine W. Wei

Irvine W. Wei

No abstract provided.

Evaluation Of Chlorine Emission Potential At The New Deer Island Wastewater Treatment Plant, Somnath Basu, Kenneth Shilinsky, Irvine Wei

Irvine W. Wei

The Massachusetts Water Resources Authority (MWRA) is currently constructing a 1,200 million gallon per day secondary wastewater treatment facility on Deer Island, in Boston Harbor. Chlorine, in the form of sodium hypochlorite solution, is purchased and barged to Deer Island for use in both effluent disinfection and odor scrubbing. The Process Engineering Department of Deer Island, as part of its on-going cost effectiveness program, is currently evaluating on-site generation of sodium hypochlorite. The technical analysis includes a thorough examination of the chemistry of production and storage, including potential losses to atmosphere. This paper presents an overview of that examination, defines …

Uv Disinfection Of Treated Wastewater Effluent: Influence Of Color, Reactivation And Regrowth Of Coliform Bacteria, Somnath Basu, Jack Page, Irvine Wei

Irvine W. Wei

Disinfection is a very important unit process to deactivate coliform bacteria in treated wastewater. However, regrowth potential of coliform bacteria raises human health and safety concerns associated with reuse of treated wastewater in various applications. Both post chlorination and post UV disinfection regrowth have been reported in the literature. In view of increasing use of recycled wastewater for reuse, it is necessary to address this phenomenon from both technical and regulatory standpoints. A case study of fecal coliform regrowth in a full scale operating plant is reported here. This is expected to aid in further understanding of the phenomenon and …

A Conceptual Continuous Process For The Treatment And Toxicity Reduction Of Wastewater Contaminated With 2,4,6-Trichlorophenol: Extended Abstract, Somnath Basu, Irvine W. Wei

Irvine W. Wei

Fenton's Reagent is an aqueous solution of ferrous ions and hydrogen peroxide. Through laboratory experiments Fenton's Reagent has been shown to be an excellent treatment agent for the removal of organic contaminants dissolved in water. It carries out oxidative degradation of various organic substrates using the principle of advanced chemical oxidation. This is an excellent alternate route for the removal of hazardous and toxic chemicals, which are recalcitrant to biological treatment. The authors of this paper conducted an extensive laboratory investigation to study the degradation of 2,4,6- Trichlorophenol (TCP) using Fenton's Reagent, reported elsewhere. The results indicated an optimum H₂O₂:TCP …

Computer Simulation Of Lime-Soda Water Softening Process, J. C. Y. Chen, I. W. Wei

Irvine W. Wei

No abstract provided.

Upflow Anaerobic Filter With Dual Media: A Novel Concept, K. Jain, I. Wei, A. Panchal, N. Varandani

Irvine W. Wei

To overcome two of the main problems intrinsic to upflow anaerobic filters using single media--clogging and biomass washout--a new strategy consisting of two different media is studied. The study is to evaluate the performance of Dual Media Upflow Anaerobic Filter (DM UAF), a novel wastewater treatment unit using synthetic waste as well as primary treated effluent of Common Effluent Treatment Plant (CETP), Vatva, India, operated by The Green Environment Services Co-Operative Society Ltd. and also to compare the performance of DM UAF with Single media UAF on a laboratory scale. Biokinetics of DM UAF was also determined. A 14.45 L …

Advanced Chemical Oxidation And Toxicity Reduction Of 2,4,6-Trichlorophenol By Using Fenton's Reagent: Part I, Kuang-Wei (Stone) Chen, Somnath Basu, Irvine W. Wei

Irvine W. Wei

The objective of this study is to exmnine the removal of a priority chlorinated aromatic pollutant, 2,4,6-Trichlorophenol (TCP), in aqueous solution by using Fenton's Reagent (a mixture of hydrogen peroxide and ferrous iron catalyst). Chlorinated phenols are priority pollutants, regulated by stringent discharge litnits. The presence of chlorine increases the toxicity of these phenolic compounds and decreases their biodegradability. Therefore, the processes of oxidation and dechlorination of chlorinated phenols by using Fenton's Reagent were employed in this study. Experiments were conducted in one-liter stirred batch reactors at 20°C. Three parallel reactors were used for reactions between 0.25 mM 2,4,6-TCP and …

An Assessment Of The Water Distribution System In The City Of Medford, Massachusetts, Yogesh Jitoo, Irvine Wei, Thomas R. Morgan, Donald Ouellette

Irvine W. Wei

The objective of this paper is to present the analysis of the water distribution system for the City of Medford, Massachusetts to identify areas of pressure deficiency. H₂OMAP Water Suite, modeling software, was used to assess the system, and using the calibrated hydraulic model of the water distribution system, the current available fire flows were compared to the required fire flows as determined by the Insurance Services Office (ISO) in 2002. Further, the influence of improvements made by the City to the distribution system from 2002 through 2004 to meet the required fire flows was evaluated. The model was also …

Water Management In Oil Shale Production, R. Edwin Hicks, Ronald F. Probstein, Irvine Wei

Irvine W. Wei

Material balance calculations for several proposed oil shale processes have been made and show that water requirements vary from 2 to 5 times the product oil rate. Wastewater is produced at from one-third to 1.5 times the product oil rate and may be treated and used to offset the source water requirement. Water management schemes are used to show the degree of treatment required for each type of wastewater. Conceptual designs of treatment trains, based on laboratory investigations of reverse osmosis, resin adsorption, biological oxidation and steam stripping processes on actual wastewaters, show that water management costs range from 60¢ …

Mixing Effects On The Chloramination Process, K. Jain, I. Wei

Irvine W. Wei

According to a recent study (AwwaRF Report 2760, 2004), more than 90 percent of water treatment plants utilizing chloramination for distribution system residuals indicate a certain level of dissatisfaction towards the process performance. One factor that may lead to such dissatisfaction is the inadequacy of mixing when ammonia is added to chlorinated water. If mixing is not uniform, the actual chlorine to ammonia nitrogen molar ratio will become variable at a micro-level, even though the overall ratio at the macro-level is close to the desired 1:1 ratio. Because of the non-uniform mixing, certain portions of the mixture might have a …

Chlorine-Ammonia Breakpoint Reactions: Kinetics And Mechanism, Irvine Wen-Tung Wei

Irvine W. Wei

No abstract provided.

Performance Of An On-Site Sewage Treatment System In Response To Revisions Of Title 5 Legislation In Massachusetts, Peter G. Annunziato, Irvine Wei

Irvine W. Wei

Regulations are being implemented by state and local governments to repress the effects of conventional on-site treatment systems that are contaminating ground and surface water reserves by infiltration of nitrogenous compounds. As of April 1995 effluent requirements have been mandated under 310 CMR 15.00, (Title 5), by the Massachusetts Department of Environmental Protection (MADEP) for flows incorporates a septic tank in series with a modified trickling (Bioclere)™ and a soil absorption field. CBOD₅, TSS removal and nitrification occurred in the Bioclere, while denitrification was initiated by recirculating nitrified effiuent to the septic tank. Prior to the Bioclere installation, septic tank …

Greater Boston Drinking Water Quality - Comparison Of Full Scale And Pilot Study I: Monochloramine And Ph Change, Xin (Cindy) Huang, Irvine W. Wei, Windsor Sung

Irvine W. Wei

Massachusetts Water Resources Authority (MWRA) has been providing drinking water for Greater Boston area since 1985. The new John J. Carroll Treatment Plant came online on July 27th, 2005. Ozone instead of chlorine is now used for primary disinfection. MWRA has been monitoring the water quality before and after the new treatment plant was online. In this paper, quantitative comparison is presented between full scale data and data from a pilot study, which was carried out two years ago to study the impact on water quality from this change in treatment.

Pilot Study Of Greater Boston Drinking Water Quality Changes - Monochloramine And Ph Change, Xin (Cindy) Huang, Irvine W. Wei, Windsor Sung

Irvine W. Wei

A pilot study was conducted from July 2001 to November 2003 to understand the impact of ozonation on monochloramine decay and pH change in the future Massachusetts Water Resources Authority's (MWRA1) drinking water system. The impact of the distribution system, which consists of old cast-iron pipes, was also investigated. Homogeneous and heterogeneous samples were taken from the Pipe Loop Pilot Plant (PLPP), which represented the best and the worst scenarios respectively, i.e. a very clean distribution system, or dead ends far from the main. The results suggested that corrosion and biological activity inside the pipe were the major causes of …

Reuse Of Municipal Wastewater As Makeup To Circulating Cooling Systems, D. Goldstein, Irvine Wei, R. Hicks

Irvine W. Wei

The reuse of municipal wastewater for industrial cooling is an excellent way of preserving clean waters for other uses. Details have been collected from several countries and there is no doubt that this is a thoroughly practical reuse option.

Makeup waters successfully used fall in the range 10-30 mg/l BOD, 30-50 mg/l o-PO₄, 1000-1500 mg/l TDS and 30-70 mg/l NH₃. The major problems are phosphate scale and biological fouling. Usual treatments are lime clarification and chlorination.

Most of the industrial users are power plants, which use high alloy metals to avoid corrosion, but industries using carbon-steel heat exchangers have not …

Remediation Of Contaminated Soil: Second Annual International Environmental Design Contest For Universities, Jeffrey Doolittle, Irvine W. Wei

Irvine W. Wei

No abstract provided.

Municipal Wastewater Reuse As Makeup To Cooling Towers, David Goldstein, John Casana, Irvine Wei

Irvine W. Wei

At the first Water Reuse Symposium in March 1979 we presented a literature survey on the reuse of municipal wastewater as makeup to circulating cooling systems. We concluded that the wastewater was useable and not excessively costly. Since then we have corresponded with most of the plants in the world who are reusing water this way (we have received information from seven plants). About half the plants surveyed use extensive chlorination and half use no chlorination at all and encourage biological activity. No plants report problems with corrosion even when ammonia is present. The old problem of foam is dying …

Analysis Of The Fate Of Chlorine Species As Part Of On-Site Generation Evaluation Of Sodium Hypochlorite At Deer Island, Somnath Basu, Kenneth Shilinsky, Irvine Wei

Irvine W. Wei

No abstract provided.

Identifying The Source Of Pressure Filters' Mudball Problem Leads To A Simple Solution: An Investigation Of Media Failure In Pressure Filtration, Fawn L. Sances, Irvine Wei

Irvine W. Wei

Within the first 17 months of operation the pressure filters at a 1.8 MGD (78.91/s) water treatment plant began having trouble. The operator first observed problems by a shortening of the filter run. When one of the hatches blew out, the operator had his first look at what was going on inside of his filters. He saw an orange slime coating the interior walls of one of the filters. Further inspection of the filters showed an accumulation of fine sediment on the top of the media and mud balls. In spite of corrective actions by its second year the plant …

Leachability Of Metals From Five Sludges, Somnath Basu, Irvine W. Wei, Paul H. King

Irvine W. Wei

No abstract provided.

Pilot Study Of Greater Boston Drinking Water Quality Changes - Impacts Of Ozonation And Distribution System, Irvine W. Wei, Xin (Cindy) Huang, Windsor Sung

Irvine W. Wei

The Massachusetts Water Resources Authority (MWRA) provides drinking water to 2.2 million people in Greater Boston. To ensure good water quality without filtration, the MWRA is about to replace chlorination with ozonation as the primary disinfection at the new Walnut Hill Water Treatment Plant, scheduled to be on-line in 2005. The objective of this study was to understand the influence of ozonation on monochloramine decay and pH change in the MWRA system. The influence of the distribution system, which consists of old cast-iron pipes, on the ozonated water was also investigated. A pilot plant, including a simulated distribution system with …

Cyclic Heating To Inhibit Bacterial Growth In Activated Carbon Point-Of-Use Treatment Devices, Irwin Silverstein, Irvine W. Wei

Irvine W. Wei

The effectiveness of using heat treatment on a cyclic basis as a means of inhibiting bacterial growth in activated carbon point-of-use treatment devices was examined. Heat treated and non-heat treated devices were compared in a controlled experiment with respect to parameters such as standard plate count, total organic carbon, total residual chlorine and head loss. The results of the study indicated that cyclic heat treatment can inhibit bacterial growth on the surface of granular activated carbon without compromising total organic carbon and total residual chlorine removal efficiencies or accelerating head loss. Microbiological testing verified that the control device had become …

Advanced Chemical Oxidation Of 2,4,6-Trichlorophenol By Using Fenton's Reagent - Dechlorination And Toxicity Reduction, Kuang-Wei (Stone) Chen, Irvine W. Wei

Irvine W. Wei

Chlorinated phenols are priority pollutants, regulated by stringent discharge limits. The presence of chlorine increases the toxicity of these phenolic compounds and decreases their biodegradability. This study is to examine the removal of a priority chlorinated aromatic pollutant, 2,4,6-trichlorophenol (TCP), in aqueous solution by using Fenton's Reagent (a mixture of hydrogen peroxide and fenous iron catalyst), in terms of dechlorination and toxicity reduction. Test results indicate that the higher the molar ratio of H₂O₂ to TCP, the faster the release of chloride from TCP. However, the chloride released in all runs eventually approach the same level of theoretical chloride concentration, …

Installation And Evaluation Of Permeable Pavement At Walden Pond State Reservation, Irvine W. Wei

Irvine W. Wei

Permeable pavements have been proposed for use in controlling surface runoff. A test installation was constructed at the Walden Pond State Reservation in Concord, Massachusetts to determine the feasibility of using permeable pavements in the New England environment. A brief history of the development and use of permeable pavements is provided. Background information, design methodology, and construction techniques are described for the data collection system and the parking area itself. All the following data are presented and discussed: mix gradation; pavement density; pavement, ground, and air temperatures; flow through permeable pavements; water quantity; water quality; and structural stability. This report …

Simulation Of Lime-Soda Softening, Li-Shiang Liang, Irvine W. Wei, Henry G. Sideropoulos

Irvine W. Wei

No abstract provided.

Mechanism And Kinetics Of Oxidation Of 2,4,6-Trichlorophenol By Fenton's Reagent, Somnath Basu, Irvine Wei

Irvine W. Wei

Fenton's reagent is an effective oxidant for pretreatment and toxicity reduction in wastewater contaminated with 2,4,6-trichlorophenol (TCP). The reaction, and its dependence on various parameters (e.g., molar ratios of the reacting chemicals, pH, temperature, etc.) have been reported elsewhere. In this paper a mechanistic interpretation of the reaction pathway, with identity of the intermediate reaction products, has been presented. An empirical expression for the rate of reaction has also been proposed in terms of the disappearance of TCP in water, as a function of the concentrations of the TCP itself and of the oxidant, hydrogen peroxide.