Engineering Commons^™

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.