LIT 11MLP UV systems are the ideal choice for disinfection of secondary and tertiary treated wastewater effluent. The flexible modular design of the 11MLP series allows UV disinfection technology to be used in a wide range of flow capacities, for waste water stations of small communities to large-scale municipal WWTPs of cities with millions of people.
- State-of-the-art low-pressure discharge amalgam lamps;
- Long guaranteed lamp operating lifetime of 12 000 hours;
- Effective chemical and mechanical cleaning technologies;
- Extensive, flexible monitoring and control capabilities;
- Electronic ballasts increase the overall system efficiency;
- UV sensors provide greater operational security
LIT 11MLP UV disinfection systems have a modular design for flexible, easy system integration, installation and operation. Developed for installation in an open channel, the 11MLP system can be provided in several configurations. Each 11MLP UV module comprises of high power low-pressure amalgam lamps arranged in two vertical columns. The UV lamps are sealed in quartz sleeves which are placed in a horizontal position, parallel to the wastewater flow in the channel. UV modules can be removed from the bank independently from each other by hand or with an auxiliary hoisting device.
All open channel UV modules are equipped with modern, industrially manufactured germicidal lamps that were developed by LIT engineers especially for wastewater disinfection. These amalgam high intensity lamps provide three times more UV intensity than conventional mercury low-pressure lamps. LIT amalgam lamps have long service life: more than 12.000 hours of continuous operation. Low depreciation of UV radiation intensity during lamp life and increased stability against water temperature variations guarantee a most effective disinfection process during the lamp's life. The spectrum of UV lamps is optimized for the germicidal effect.
Cabinets with high efficiency electronic ballasts are installed near each UV bank above the channel. Each UV module is connected to the electronic ballast cabinet through a pair of waterproof plugs.. Each cabinet has a small LCD display to provide information about the UV modules and UV lamp status in each bank.
The operation of the UV plant is guided through a Control Cabinet on basis of an industrial PLC system. The front of the cabinet is provided with a control panel with graphical user interfaces to control the UV system, which can be operated both in automatic and manual modes. All operational data from the UV system can be transmitted to the main WWTP control centre through the standard industrial serial bus. The Control System incorporates a data logging function for recording all operating parameters.
Each bank of UV plant is equipped with two UV radiation intensity meters. The UV sensor measures the UV intensity inside the UV bank, converts the analogue signal to a digital form and transmits it to the Operating and Control system.
Each disinfection channel is equipped with an automatic level control system. It consists of a motorized sliding gate mounted at the channel outlet, a PLC controller and an ultrasonic and/or variable-capacitance water level sensor. A level control system maintains the proper water level inside the disinfection channel at 0-100% flow variations. It prevents overflows and guarantees that all water will be treated properly without bypassing the UV modules.
The 11MLP UV system design is provided with chemical cleaning system for the quartz sleeves in each channel without removing lamp modules from the channels. All lamps in each channel are cleaned simultaneously. During the cleaning period a UV channel is closed and water effluent passes through remaining channels. The cleaning system consists of a tank for washing solution preparation, circulation pump, a system of pipes from stainless steel and switching valves.
At high levels of suspended solids in the wastewater an optional automatic mechanical wiping system can be supplied with 11MLP UV modules, to clean the quartz sleeves without removing UV modules from the channels. It prevents quartz sleeve fouling during UV system operation and removes deposits from the quartz sleeve surface by mechanical wipers which are moved periodically along quartz tubes. The wiping frequency can be adjusted through the PLC control unit. The pneumatic/hydraulic cylinders are powered by an air compressor.
- UV Module Service Rack
The 11MLP UV system includes a mobile frame to fit the extracted modules during service works (e.g. lamp replacement). Each frame is designed to support 2 lamp modules for repair, cleaning or storage.
- Flow Equalizing Gratings
At space limited conditions, when the channel length is restricted, stainless steel gratings with profiled holes are installed at each channel entry to provide a better water flow mixing and distribution across the channel.
- Channel Cover Plates
The channels with UV banks can be covered by profiled zinc galvanized steel plates.