This paper provides rationale for key assumptions and decisions made in developing the
design for the ultraviolet (UV) disinfection system for the in-plant recycle stream treatment
system at the East Bay Metropolitan Urban District (EBMUD) Walnut Creek Direct Filtration
Water Treatment Plant (WTP). Results of the analysis are as follows:
Cryptosporidium is the target pathogen for UV inactivation in the recycle stream;
free-swimming pathogens are the basis of UV dose selection; and,
design dose for the system is 40 mJ/cm2;
acceptable UV systems have attributes that include
validated UV dose and UV sensor response,
closed-vessel configuration, and
mechanical cleaning of quartz sleeves and UV sensor probes;
UV transmittance of 85% (254 nm and 10 mm pathlength);
approximate capital cost of $1.1 million for current conditions; and,
approximate O&M cost of $0.06 per 1,000 gallon for current conditions. The purpose of this paper is to provide conceptual level layouts and cost estimates for
ultraviolet (UV) disinfection for in-plant recycle streams. Specific components of this
analysis and corresponding organization of this paper are as follows:
establish disinfection goals and UV dose requirement;
discuss attributes of acceptable UV systems;
develop UV disinfection system configuration and layout; and,
present estimates for capital and operational costs.
The following are the general performance goals of the UV disinfection system:
provide inactivation of Cryptosporidium and other chlorine-resistant pathogens in in-plant recycle streams; and,
provide reliable UV equipment, systems, and operational strategies. Includes tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 2.6 MB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 16 |
| Published : | 06/16/2002 |
