1 foreword

The water quality on-line automatic monitor system is a set take the on-line automated analysis instrument as the core, the utilization modern sensor technology, the automatic survey technology, the automatic control technology, the computer application technology as well as correlation special-purpose analysis software and the communication network composes a comprehensive on-line automatic monitor data, statistical, processing monitor data, but printout date, week, month, season, year even uniform data as well as date, week, month, season, year maximum value, minimum value and so on each kind of monitor, statistical report and graph (clavate chart, diagram of curves multi- trajectory diagrams, contrast chart and so on), And may input the central database or access the net. The collection and may the long-term memory assign the monitor data and each kind of movement material, the environment material prepare the retrieval. The system has the monitor project to exceed the allowed figure and the sub- station condition signal demonstrated, reports to the police the function; The automatic movement, the power cut protection, comes the electricity self-recovery function; The maintenance examines the oak condition test, is advantageous for function and so on routine maintenance and emergency breakdown processing.
The implementation water quality automatic monitor, may realize the water quality real-time continuous monitoring and the long-distance monitoring, achieved and grasps the main basin key cross section water body the water quality condition, the early warning forecast is significant or the basin water pollution accident, solves the cross administrative division water pollution accident dispute, inspector general total quantity control system goal and so on realization situation, platoon unconventional sign situation.

2 water quality automatic monitors technology

2.1 water quality automatic monitors system constitution
In the water quality automatic monitor system network, the central station dials through the satellite and the telephone holds in the mouth two kind of communications ways realization to each sub- station real-time surveillance, the long-distance control and the data transmission function, is entrusted with stands also may through the telephone digit dialing way realization to holds 管子�?the real-time surveillance, the long-distance control and the data transmission function, other have produced presently the real-time surveillance and the data transmission after the authorized related department passable telephone digit dialing way which stands to the climax or energy.
Each stature station is an independent integrity water quality automatic monitor system, generally constitutes by 6 major subsystems, including: The sampling system, the pretreatment system, the monitor instrument system, the PLC control system, the data acquisition, processing and the transmission subsystem and the long range data administrative center, the monitor 站房or monitors the hut. At present, in the water quality automatic monitor system subsystem and the long range data administrative center, the monitor 站房or monitors the hut. At present, in the water quality automatic monitor system sub- station constitution way approximately has three kinds:
(1) by or a many small multi- parameters water quality autoanalyzer (for example: YS1 Corporation and the HYDROLAB Corporation's conventional five parameters analyzer) composes the sub- station (many combinations may use in to survey different water depth water quality). Its characteristic is the instrument may directly put Yu Shuizhong to survey, the system constitution nimble is convenient.
(2) fixed formula station: For compares traditional the system composition way. Its characteristic is monitors the project the choice scope to be wide.
(3) mobile formula station: One kind completely installs for the fixed formula station instrumentation equipment to a trailer (monitors hut) on, may according to need to migrate the place, also may think is half fixed formula station. Its characteristic is composes the cost to be higher.
Various units through the water sample transportation circuitry, the signalling system, the compressed air transportation circuitry, the pure water transportation circuitry realization mutually relate.
May * the natural very high water quality automatic monitor system, have simultaneously to have 4 essential factors, namely (1) high grade system equipment; (2) complete system design; (3) strict construct control; (4) responsible movement management.

2.2 water quality automatic monitors technical key
2.2.1 picks the water unit
Including the water pump, the pipeline, supply power and installs the structure to be partial. In the design must to in each kind of climate, the terrain, the water level change and the water the silt and so on proposed the corresponding solution measure, can be automatic continuously with the overall system synchronization work, provides to the system may *, the effective water sample.
2.2.2 matches the water unit
Including water sample pretreatment installment, self-cleaning installment and auxiliary body. Matches the water unit directly to the automatic monitor instrument water supply, has on-line eliminates the silt and on-line filters, manual and the automatic pipeline counter- flushing and eliminates the algae installment; Its water quality, the hydraulic pressure and the water volume should satisfy automatically monitors the instrument the need.
2.2.3 analyses units
Are composed by a series of water quality automated analysis and the metering equipment, including: The water temperature, PH, 溶解�?(DO), the conductivity, the turbidity, the ammonia nitrogen, the chemical oxygen demand, the permanganate index, 总有机碳 (TOC), the total nitrogen, the total phosphorus, the nitrate, the phosphate, the cyanide, the fluoride, the chloride, the phenol class, the oil class, the metallic ion, 水位�? the current capacity/current capacity/flows to takes into account composition and so on the automatic sampling. Each main on-line automated analysis instrument development present situation 3rd will relate in detail.
2.2.4 control units
Including: (1) systems control cabinet and systems control software; (2) data acquisition, processing and memory and its application software; (3) wire communication and satellite communication equipment.
2.2.5 sub- stations 站房and necessary facility
Including: (1) 站房main body; (2) necessary facility

3 on-line automated analyses instruments development

3.1 outlines
The water quality automatically monitored the instrument still during the development, country and so on Europe, America, Japan, Australia had some specialized merchant productions. At present, includes after the maturer conventional project: Water temperature, PH, 溶解�?(DO), conductivity, turbidity, redox potential (ORP), speed of flow and water level and so on. The commonly used monitor project includes: COD, permanganate index, TOC, ammonia nitrogen, total nitrogen, total phosphorus. Other also have: Fluoride, chloride, nitrate, nitrite, cyanide, sulfate, phosphate, active chlorine, TOD, BOD, UV, oil class, phenol, chlorophyll, metallic ion (for example six prices chromium) and so on.
The present autoanalyzer generally has the following function: The automatic measuring range transforms, the remote control, the standard output connection and the numeral demonstrated, self-cleaning (when clean has data locking function), the condition self-checks and reports to the police the function (for example: The liquid divulges, line clogging, the superhigh measuring range, the instrument internal hyperpyrexia, the reagent with the ruler, the high/low density, the power failure and so on), does the revolution and the power failure protection, comes the electricity self-recovery, instrument and so on COD, ammonia nitrogen, TOC, total phosphorus, total nitrogen to have automatically demarcates the adjustment function.

3.2 conventional five parameters analyzers
The conventional five parameters analyzers frequently use flow 通式 the multi- sensors survey pond structure, does not have a zero drifting, does not need the baseline to adjust, has the integrated biology clean and the compressed air purifier. For example: English ABB Corporation produces the EIL7976 multi- parameters analyzer, French Polymetron Corporation produces the conventional five parameters analyzers, Australian GREENSPAN Corporation produces Aqualab multi- parameters analyzer (including conventional five parameters, ammonia nitrogen, phosphate). Another kind of type ("4+1") the conventional five parameters autoanalyzers representative is the MP2000 multi- parameters on-line not nature analyzer which French SERES Corporation produces, its characteristic is the instrument structure is compact.
The conventional five parameters survey principles respectively are: The water temperature for the temperature sensor law (Platinum RTD), PH is the glass or 锑电�?the law, DO is the golden - silver membrane electrode law (Galvanic), the conductivity for the electrode law (exchange 阻抗�?, the turbidity for the light research method (transmission principle or infrared scattering principle).

3.3 chemical oxygen demands (COD) analyzer
The COD on-line autoanalyzer main technical principle has six kinds: (1) the potassium bichromate dispels - the luminosity to measure the mensuration; (2) the potassium bichromate dispels - the coulomb titrimetric method; (3) the potassium bichromate dispels - the reduction method; (4) UV counts (254nm); (5) 氢氧�?and the ozone (mixes oxidant) to oxidize - the electrochemistry to measure the mensuration; (6) the ozone oxidation - electrochemistry measures the mensuration.
Says from the principle, the method (3) approaches the GB code method, the method (2) also is the recommendation unified method. The method (1) already used on the fast COD determination instrument. Method (5) and method (6) although does not belong to GB code or the recommendation method, but in view of the fact that its has the movement may * and so on the characteristic, in the practical application, only have carries on its analysis result and the GB code method compared to after experiments and carries on the suitable adjustment, then gives to approve. But the method (4) uses in table piece water quality COD, although obtained a more widespread application in Japan, but the European and American various countries not yet applies (has not obtained administrative hosts and visitors department approval), still had to carry out the related research in our country.
Says from the analysis performance, on-line COD meter survey scope generally in 10 (or 30) ~2000mg/l, therefore, the present on-line COD meter only can satisfy the source of pollution on-line automatic monitor the need, should use in with difficulty the surface water automatic monitor. Moreover, with uses the electrochemistry principle the instrument to compare, uses dispels - the reduction method, dispels - luminosity method instrument minute cyclical generally longer somewhat (10min~2h), former generally is 2~8min.
Says from the instrument structure, uses the on-line COD meter which the electrochemistry principle or UV counts generally compared to use dispels - the reduction method, dispels - the luminosity method instrument structure simply, and because former enters the type and the reagent easily joins the system (to pump, tube few), therefore not only in operation more convenient, moreover its movement may * the nature be also better.
Says from the maintenance difficulty degree, because dispels - the reduction method, dispels the reagent type which - the luminosity law uses many, pump pipe system more complex, therefore in reagent replacement as well as pump pipe replacement maintenance aspect troublesomer, maintains 周期�?uses the electrochemistry principle the instrument to have to be short, maintains the work load to be big.
From the influence aspect says to the environment, the potassium bichromate dispels - the reduction method (or luminosity law, or coulomb titrimetric method) has the chromium, the mercury two contamination concern, the waste liquid needs special processing. But UV counts the law and the electrification research method (including coulomb titrimetric method) does not have this kind of problem.

3.4 permanganates indexs analyzer
The permanganate index on-line autoanalyzer main technical principle has three kinds: (1) permanganate oxidation - chemistry measures the mensuration; (2) permanganate oxidation - electric current/potentiometric titration; (3) UV counts the law (and the on-line COD meter similar).
Says from the principle, the method (1) and the method (2) and the non- essential difference (only is end point instruction way difference), in country and so on Europe and America and Japan is the legal method, with the our country standard method also is consistent. (3) uses in the method to attribute the water quality permanganate index the method, obtained a more widespread application in Japan, but not yet promotes the application in our country, also has not obtained the administrative hosts and visitors department the approval.
Says from the analysis performance, the present permanganate index on-line autoanalyzer has been able to satisfy the surface water on-line automatic monitor the need. Moreover, compares with the color and chemistry method instrument, uses the reduction method instrument analysis cycle generally longer somewhat (2h), former generally is 15~60min.
Says from the instrument structure, two kind of instruments structures quite are complex.

3.5 总有机碳 (TOC) analyzer
The TOC autoanalyzer in country's the and so on Europe and America, Japan and Australia application is more widespread, its main technical principle has four kinds: (1) (catalysis) burns the oxidized - non- disperser infrared luminosity law (the NDIR law); (2) the UV catalysis - peroxydisulfate oxidizes the -NDIR law; (3) UV- peroxydisulfate oxidation - ion choice electrode law (ISE) law; (4) heats up - the peroxydisulfate to oxidize the -NDIR law; (5) the UV-TOC analysis counts the law.
Says from the principle, only then shows (1) to approach the GB code method, but the method (2) the ~ method (4) in country and so on Europe and America also is the legal method. (5) uses in the method to attribute water quality TOC, although obtained a more widespread application in Japan, but not yet obtains the administration department responsible for the work in the European and American various countries the approval.
Says from the analysis performance, the present on-line TOC meter definitely can satisfy the source of pollution on-line automatic monitor the need, and because its examination limits lowly, applies to the surface water automatic monitor also is feasible. Moreover, the on-line TOC meter analysis cycle is generally shorter (3~10min).
Says from the instrument structure, removes the unit besides the increase inorganic carbon, each kind of on-line TOC meter structure on-line COD meter is generally simpler than some.

3.6 ammonia nitrogen and total nitrogen analyzer
The ammonia nitrogen on-line autoanalyzer technical principle mainly has three kinds: (1) ammonia sensitive electrode 电位�?(PH electrode law); (2) spectrophotometric method; (3) Fourier transforms the spectrographic methods. The on-line ammonia nitrogen meter and so on needs continuously and the interrupted survey way, after passes through the on-line filtrating equipment, the water sample measured the definite value relative deviation is bigger.
The total nitrogen on-line automatic minute meter main technical principle has two kinds: (1) the peroxydisulfate dispels - the luminosity law; (2) airtight burning oxidation - 化学发光 analytic method.

3.7 phosphate and total phosphorus analyzer
(Reactivity) the phosphate autoanalyzer main technology principle is the luminosity law. The total phosphorus on-line autoanalyzer main technical principle includes: (1) the peroxydisulfate dispels - the luminosity law; (2) the ultraviolet ray illumination - molybdenum catalysis heats up dispels, FLA- luminosity law.
Says from the principle, the peroxydisulfate dispels - the luminosity law is the on-line total nitrogen and the total phosphorus meter host chooses the method, also is the various countries' legal method. Heats up based on the airtight burning oxidation - 化学发光 analytic method on-line total nitrogen meter as well as based on the ultraviolet ray illumination - molybdenum catalysis dispels, the FIA- luminosity method on-line total phosphorus meter mainly limits to Japan. Former is one of methods which the Japanese industry specification association (JIS) approves.
Says from the analysis performance, the present on-line total nitrogen, the total phosphorus meter have been able to satisfy the source of pollution and the surface water automatic monitor need, but the sensitivity still with difficulty satisfied appraises kind of, two kind of surface waters (standard value respectively was 0.04mg/l and 0.02mg/l) the water quality need. Moreover, uses 化学发光 the law, FIA- luminosity method instrument analysis cycle generally shorter somewhat (10~30min), former generally is 30~60min.
Says from the instrument structure, uses nonluminous method or the FIA- luminosity method on-line total nitrogen, total phosphorus meter structure simpler somewhat.

3.8 other analyze the instrument in the line segment
TOD autoanalyzer: Technical principle generally for burning oxidation - electrode law.
Oil class autoanalyzer: The technical principle generally is the fluorescence luminosity law.
Phenol class autoanalyzer: The technical principle generally is a color method.
UV autoanalyzer: The technical principle is the color method (254nm). Has simply, is quick, the price low characteristic. Is ill to the surface water automatic on-line monitor, overseas generally is uses in the source of pollution automatic monitor, and frequently passes through the conversion to express COD, the TOC value. Using the prerequisite is the water quality is stabler, has the more definite linear correlation relations in the UV absorption signal and COD or between the TOC value.
Nitrate and cyanide autoanalyzer: The technical principle mainly has: (1) ion choice electrode law; (2) luminosity law.
Fluoride and chloride autoanalyzer: Technical principle generally for ion choice electrode law.