Wastewater Treatment. UV/Ultrasound. UV/Ultrasound Disinfection System

Transcription

1 Wastewater Treatment UV/Ultrasound UV/Ultrasound Disinfection System

2 UV/Ultrasound Disinfection System IN THE UNITED KINGDOM, UV LIGHT IS BECOMING THE MOST COMMON MEANS OF DISINFECTION BECAUSE OF THE CONCERNS ABOUT THE IMPACTS OF CHLORINE IN CHLORINATING RESIDUAL ORGANICS IN THE WASTEWATER AND IN CHLORINATING ORGANICS IN THE RECEIVING WATER. THE ELIQUO HYDROK LAZUR UV PROCESS HAS OVERCOME THE DISADVANTAGES ASSOCIATED WITH CONVENTIONAL UV DISINFECTION.

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4 IMPORTANT FACTORS The most common draw backs to conventional UV disinfection processes are: Lamp and reactor fouling Frequent lamp maintenance and replacement and Shielding of micro-organisms from UV radiation in poorly treated wastewater. The ELIQUO HYDROK system utilises low pressure amalgam lamp technology (UV dose > 65 mj/ cm 2 ) with ultrasound (US dose > 2 W/ cm 2 ) in a single unit. The combination of these two technologies virtually eradicates the common problems associated with UV disinfection. In addition, ultrasound augments the disinfection of the low pressure UV lamp process. LAMP MAINTENANCE Common UV maintenance issues: Mechanical cleaning in most cases requires periodic offline manual chemical cleaning. Mechanical wiping systems cause scratches on lamp sleeve surfaces that favour the formation of permanent foulants. Thermally-induced precipitation of inorganic species and impaction of pre-existing colloidal particles are the primary mechanisms responsible for inorganic fouling. ELIQUO HYDROK Lazur low pressure lamps generate low temperatures on the Tube Sleeve Surface, and ultrasound allows for non-intrusive tube sleeve cleaning zero sleeve scratches and no need to take the system offline for mechanical and chemical cleaning. The high intensity amalgam lamps have low decline in UV light flux - 5 to 10% towards the end of service life compared with 20 to 30% for conventional UV systems. ENERGY EFFICIENCY Inactivation of pathogens at shorter exposition times and lower energy consumption: 5 seconds of combined UV and Ultrasound are equivalent to 30 seconds of conventional UV The systems consume low energy: kwh per 1 m3 for drinking water, and 0.02 kwh per 1 m3 for treated industrial or sewage effluent. High bactericidal efficiency coupled with low capital, operational and maintenance costs make these systems a very competitive product for water disinfection needs. Research into combined application of UV and Ultrasound in waste water disinfection by T. Blume and G. Neiss at the Hamburg-Harbug Technical University, Germany Number of coliform bacteria in 100 ml Log inactivation

5 ENHANCED MICROBE EXPOSURE TO UV RADIATION Turbulence is generated by a baffle, as the water to be treated enters the reactor. Clumps of solids are destroyed by the ultrasound that would otherwise shield the microbes and prevent them from being radiated. The UV process can be applied to treat waters of low quality: UVT down to 60% Suspended solids up to 20 mg/l MOVEMENTS IN WASTEWATER DISINFECTION The current EC Bathing Water Directive sets two standards; a mandatory and a more stringent guideline (Table 1). Mandatory Limit Stringent Guideline Limit UK Blue Flag Award T. coliforms 10,000 / 100 ml 500 / 100 ml F. coliforms 2,000 / 100 ml 100 / 100 ml F. streptococci 100 / 100 ml %ile Limit The revised Bathing Water Directive changes are significantly more stringent than those of the current directive and all bathing waters are required to be sufficient, or better, by Excellent: Approximately twice as stringent as guideline Good: Comparable to guideline Sufficient: Approximately twice as stringent as mandator Poor: Non-compliance with the revised directive standards

6 Combined Ultra Violet and Ultra sound disinfection technology. Version 001 ELIQUO HYDROK LTD Indian Queens Ind Estate, St. Columb I Cornwall, England I TR9 6TL T sales@eliquohydrok.co.uk I MEMBER OF ELIQUO WATER GROUP