Water quality monitoring and analysis instruments and equipment

Configuration Composition

The online water quality monitoring station consists of a water collection unit, a water distribution unit, a water quality analysis unit (conventional five parameter analysis unit, permanganate index/ammonia nitrogen analysis unit, total phosphorus/total nitrogen analysis unit, chlorophyll/blue-green algae analysis unit), an auxiliary unit, a data acquisition and control unit, an on-site monitoring and data transmission unit, etc. The auxiliary unit consists of several sub units such as power distribution system, UPS unit, compressed air unit, lightning protection unit, and on-site operation console.

Function

The on-site control software includes system pipeline diagram and real-time status display, instrument status and real-time data display, data query/export/automatic backup function, parameter setting function, alarm information display, manual and single control function, system and instrument historical operation status display, operation prompt function, user management function, etc.

can remotely set and collect the working status parameters of monitoring station instruments and equipment, and detect and control the sampling, blowback, cleaning, working status of instruments and equipment, monitoring station working environment, and safety control according to the above requirements.

Installation Method

Typical facilities include water quality section markers, water collection facilities, station buildings, etc.

a)Water quality section markings. The water quality sampling section facilities mainly use section identification, which can be in the form of marble or titanium alloy plates, with clear identification and easy recognition.

b)Water harvesting facilities. The construction of water harvesting units should adopt different water harvesting methods according to local conditions. According to the structural characteristics of different water harvesting methods, they can be divided into wharf type water harvesting, float/boat/float type water harvesting, cantilever type water harvesting, floating bridge type water harvesting, cable type water harvesting, etc. The location of the water harvesting device in the river, lake and reservoir should ensure normal water harvesting while not affecting navigation channels. The applicable conditions for different types of water harvesting methods are shown in the table.

Conditions for the use of different types of water harvesting methods

Pier style water harvesting. The wharf type water collection device is set as level as possible with the height of the river embankment, and is composed of water collection guide rods, water collection floats, water collection pipelines, lifting motors, steel cables, and water pumps. Install warning signs on the wharf.

The wharf type water harvesting facility is suitable for monitoring sections with large changes in riverbed, but small changes in water level (within 10m), and small water depth (within 5m). The water harvesting head can float up and down with changes in water level, but cannot move horizontally. Combined with an electric hoist, it can control up and down free movement, and the water harvesting float can be maintained on the wharf.

Float type water extraction. The float type water collection device is set as flush as possible with the station building, and is composed of a water collection float, water collection pipeline, ship anchor, steel cable, and water pump. The water collection float, reinforced concrete, and ship anchor are connected by steel cables to ensure that the water collection device is not washed away by the water flow. Fixed pins are installed at suitable positions upstream of the river lift, and steel wire ropes are used to connect the water collection device for easy maintenance in the later stage.

The pontoon water extraction method is applicable to monitoring sections with large water depth and large water level changes, such as rivers, lakes and reservoirs. The sampling head can float up and down with certain changes in water level, and can also have a certain degree of horizontal displacement.

Cantilever water harvesting. The cantilever water collection device is composed of a water collection float, a water collection guide rod, a water collection pipeline, a concrete pier, a steel cable, and a water pump. The water collection float and the water collection guide rod are connected by a steel cable to ensure that the water collection device is not washed away by the water flow. Install warning signs above the buoy.

Cantilever water harvesting is applicable to automatic stations located in river tributaries and lakes within the area, with a river width of less than 30m, small water level changes (within 3m), and slow water flow velocity (within 5m/s); The complex terrain makes it inconvenient to use fixed bridge piles, or temporary water intake wharf schemes are adopted to avoid the impact of river regulation. The advantages are factory processing, on-site assembly, short construction period, rotatable, and easy maintenance.

Floating bridge water harvesting. The floating bridge type water collection device is composed of foundation columns, steel cables, floating bridges, water collection floats, water collection pipelines, and water collection pumps. The floating bridge for water collection can freely float up and down with changes in water level. Warning signs should be installed on the floating bridge for water collection, and the construction location of the floating bridge water collection device should ensure normal water collection without affecting the waterway.

Lasso type water extraction. The lasso type water collection device is composed of foundation columns, steel cables, pulleys, traction motors, water collection floats, water collection pipelines, and water collection pumps. It should be installed on both sides of the water collection section of the river to achieve sampling of any water collection point on the entire section. The water collection device can freely float up and down with changes in water level. Install warning signs on the water collection device. This method is applicable to sections without navigation requirements.

Lasso type water harvesting facilities are suitable for water level changes within 8m, water flow velocities less than 2.0m/s, and river channel widths within 100m. The two support points of the cableway are built on the riverbank to ensure that the water collection device can withstand the impact of floods when the river channel is flooded; The water collection float can be controlled by an electric motor to collect water from any point on the river section.

Submerged water sampler. Connect the sampling float rod, the water intake port below, the water intake pipeline, and the injection port of the water pump assembly. The water pump assembly consists of a sealed chamber and two submersible pumps enclosed in the chamber. Due to buoyancy, the water intake below the floating rod is generally located about 0.5m below the water surface. When the system starts the water pump to collect water, the water to be measured enters the pump assembly cavity through the pipeline from the water intake and is pumped into the station building.

The submerged water sampler is suitable for various complex environments and can be applied to monitoring sections such as lakes, reservoirs, and rivers with rapid water flow, long shallow waters, and water level changes of less than 80m. The water collection rod floats up and down according to changes in water level, and the water collection outlet is located 0.5-1m below the water surface, which meets relevant regulatory requirements. The installation method of the water collection device sinking to the bottom can ensure that the water collection equipment can withstand the impact of floods, does not affect the passage of waterways, and guarantees the safety and normal operation of water collection facilities.

Sliding rail water harvesting. The slide rail water collection device is composed of a slide rail foundation column, a track, a water collection float, a water collection pipeline, and a water collection pump. The water collection float and slide rail are connected by steel cables to ensure that the water collection device will not be washed away due to water flow velocity. It is suitable for monitoring sections such as lakes, reservoirs, and rivers with fast water flow and small water level changes. Install warning signs on the floating bridge for water collection.

Station Building

Large and medium-sized stations adopt fixed station building style, while small stations adopt box type. The station building needs to meet the requirements of automatic water quality monitoring. Large fixed station buildings include monitoring instrument rooms, quality control rooms, and duty rooms, which are constructed in single or double layers; The quality control room and monitoring instrument room of medium-sized station buildings can be combined for construction. Necessary measures such as dehumidification and temperature control should be taken in the station building to ensure the environmental requirements for water quality monitoring.