Nur Muhammad

Biomass characterization of slow sand filtration schmutzdecke and its effects on filter performance

Abstract A new approach of representing biomass by measuring the Total Kjeldahl Nitrogen (TKN) content of sand in the schmutzdecke of slow sand filtration (SSF) was established by correlating TKN, Volatile Solids (VS) and Total Plate Count, a better way for the representation of biomass against the usual method by measuring VS. Reasonably good correlations were found between TKN and Chemical Oxygen Demand (COD) and Biochemical Oxygen Demand (BOD) of the extract from the schmutzdecke sand. The effects of the concentration of TKN on the efficiency of the SSF used as a tertiary unit of a wastewater treatment plant in removing BOD, COD, Ammonia Nitrogen (NH3‐N) and Total Microorganisms have been evaluated and better performances of the filter have been observed at higher TKN concentration. The removal of NH3‐N was almost proportional to TKN concentration further proving the importance of measuring the NH3‐N in the effluent to identify the degree of ripening of the filter.

Evaluating a composite cartridge for small system drinking water treatment.

A pilot-scale evaluation was conducted at the U.S. Environmental Protection Agency (EPA) Test & Evaluation (T&E) Facility in Cincinnati, Ohio, on a multi-layer, cartridge-based system that combines physical filtration with carbon adsorption and ultraviolet (UV) light disinfection to serve as a home-base water treatment security device against accidental or intentional contaminant events. The system was challenged with different levels of turbidity, a number of biological contaminants including Bacillus subtilis, Escherichia coli, MS2 bacteriophage and Polystyrene Latex (PSL) beads as a surrogate for Cryptosporidium and a number of chemical contaminants including super-chlorination, methyl tertiary butyl ether (MTBE), water chlorination disinfection byproducts (DBPs) and diazinon. The results demonstrated that the performance of the system varies as a function of the specific contaminant or surrogate. The overall performance indicated the potential of the system to improve the quality and safety of household water and to serve as an additional treatment barrier in circumstances where there is little or no treatment or where the quality of treated water may have deteriorated during distribution. The results also demonstrated that B. subtilis spore can serve as a more conservative surrogate for Cryptosporidium than PSL beads.

Evaluation of Ceramic Filtration for Drinking Water Treatment in Small Systems

There are approximately 50,000 small community systems and 140,000 noncommunity systems serving over 25 million transient and non-transient populations of 3,300 people or less. Several of these small systems are having difficulty complying with the ever increasing number of regulations and regulated contaminants and it is estimated that small systems contribute 74 % of the Safe Drinking Water Act (SDWA) and its Amendments (SDWAA) violations annually. Nearly 90% of these are for Maximum Contaminant Level (MCL) violations. EPA conducts in-house technology development and evaluation to support the small communities. As part of this research effort, EPA has been evaluating a ceramic filtration system for the production of drinking water. The system is being challenged with various turbidity levels, Cryptosporidium (using polystyrene latex beads as a surrogate) and Bacillus Subtilis (to evaluate bacteria removal). This paper presents the results of studies conducted to date on this system. Future research efforts will include testing the system for removal of total coliforms, MS2 bacteriophage and Cryptosporidium parvum.

Assessment of a Point-of-Use Ultrafiltration System for Turbidity and Microbial Pathogen Removal

U.S. EPAs Office of Research and Development has been evaluating the performance of point-of-use (POU) devices designed for use in homes and small businesses for many years. In collaboration with the University of Cincinnati, a series of pilot-scale tests were conducted on a Matrix Membranes ultrafiltration (MMUF) system at the U.S. EPA Test and Evaluation Facility in Cincinnati, Ohio. The MMUF system operates at a low flow rate ( E. coli ). Other parameters of interest included system flux, runtime, raw water characteristics, and operating cost. Results are summarized and presented on turbidity and microbial removal efficiency.

Evaluation of Point of Use (POU) Systems for the Removal of Microbiological Contaminants in Drinking Water

As a final barrier before consumption, properly designed and operated Point-of-Use (POU) treatment systems are important for safe drinking water supplies. POU treatment devices have gained importance for protection against intentional or accidental contamination of drinking water supplies. The events of September 11, 2001 have further emphasized the importance of POU devices in this regard. This paper summarizes the results of pilot-scale studies that were conducted at the U.S. Environmental Protection Agency’s (EPA’s) Test and Evaluation (T&E) Facility in Cincinnati, Ohio, to evaluate the performance of three different POU systems for removing microbiological contaminants in drinking water. Two of these systems were based on filtration through electrostatically charged media and the third system incorporated a reverse osmosis (RO) membrane. The systems were challenged with a number of microbiological contaminants including Cryptosporidium, E. coli, MS2 bacteriophage, B. subtilis and polystyrene latex (PSL) beads (as a surrogate for Cryptosporidium). The results demonstrated that these POU systems were effective in removing the target biological contaminants in accordance with the standards presented in the U.S. EPA “Guide Standard and Protocol for Testing Microbiological Water Purifiers” (USEPA, 1987).

Diffuse pollution in Oxford (Ohio, USA) watershed and performance of 'street sweeping' as a 'best management practice' (BMP).

Experimental results are described to evaluate the diffuse pollution profile according to land use in the catchments and street sweeping as a best management practice (BMP). We studied the variation of pollutant concentrations in outfalls discharging runoff from residential, commercial and high-traffic areas and in street sweeping. Pollution profiles varied with the land use in the catchments and seasons along with other factors such as rainfall intensity, construction works and street maintenance. Microbial indicator organisms were relatively high in all three outfalls. Heavy metal concentrations were low with lead (Pb) as the predominant heavy metal. The organic and solid contents were low but non-degradable and persistent. Relatively high quantities of pollutants were found in street sweeps in all catchments suggesting street sweeping as an effective measure to control diffuse pollution. Regular and frequent sweeping is important as a BMP.

Evaluation of Long-Term Performance of Point of Use (POU) Systems for Drinking Water Treatment

The U.S. Environmental Protection Agency (EPA) initiated a research program in 2008 at the EPA Test and Evaluation (T&E) Facility in Cincinnati, Ohio to evaluate the performance of various Point-of-Use (POU) treatment devices for providing drinking water in homes and transient non-community water systems, either routinely or as an emergency measure during accidental or intentional contamination events. This paper describes the results of the performance of two POU devices based on reverse osmosis (RO) technology. The POU devices were continuously operated for about 22 months (670 days) to evaluate their long-term performance and challenged with microbiological contaminants at different time intervals to evaluate continued treatment effectiveness. The microbiological contaminant challenge contaminants included E. coli, MS2 bacteriophage, B. subtilis and polystyrene latex (PSL) beads (evaluated as a non-biological surrogate for Cryptosporidium). The results of tests conducted to date show complete removal of the selected microorganisms and surrogates by the POU systems both at startup and after 22 months of operation. The two RO-based POU systems satisfied the LongTerm 2 Enhanced Surface Water Treatment Rule (LT2ESWTR) requirements for Cryptosporidium removal. The POU devices performed favorably when compared to the reduction requirement of the EPA Guide Standard Protocol for Microbiological Water Purifiers (U.S. EPA, 1987), which is 6 log for bacteria and 4 log for viruses. Notice: The U.S. Environmental Protection Agency, through its Office of Research and Development, funded and managed the research described herein. Any opinions expressed in this article are those of the author(s) and do not necessarily reflect the official positions and policies of the EPA. Any mention of products or trade names does not constitute recommendation for use by EPA.