CN101699229B - On-line soft sensing method for flow of inlet water of ozonation contact reactor in water plant - Google Patents

Abstract

The invention discloses an on-line soft sensing method for the flow of inlet water of an ozonation contact reactor in a water plant. Aiming at the problem of failure to measure the flow of inlet water of an ozonation contact reactor in a water plant on line due to the restrictions of technological conditions, the invention provides a test method of an inlet water lift pump of an ozonation contact reactor permitted under the on-line working conditions. By obtaining the frequency-flow correspondence curve of the operation of the lift pump at the actual maximum working pump lift Hmax and the actual minimum working pump lift Hmin, a monitoring computer in a central control room generates the real-time frequency-flow correspondence curve at the current working pump lift Hreal based on the measured current working pump lift Hreal and the frequency-flow correspondence curve obtained by tests in the subsequent automatic control process of ozone dosage, and further obtains the real-time flow of the inlet water of the ozonation contact reactor by inquiring the curve to automatically obtain the real-time flow of the inlet water lift pump of the ozonation contact reactor. The invention has the advantages of practicability, reliability, no additional cost and wide applicability.

Description

The online soft sensor method of a kind of water factory ozone contact tank flow of inlet water

Technical field

The present invention relates to the measuring method of a kind of water factory ozone contact tank flow of inlet water, relate in particular to a kind of online soft sensor method of ozone contact tank flow of inlet water.

Background technology

The numerous town dwellers' of China potable water basic source is a tap water, and tap water confrontation resident's is healthy most important, requires to accomplish sense organ aspect water white transparency, and nothing is smelt tasteless; Aspect chemical, do not contain harmful poisonous substance; Aspect bacteriology, do not contain pathogenic bacteria, thus all restricted to Escherichia coli and total number of bacteria.To the former water of III class water quality, the waterworks adopts traditional conventional treatment process can satisfy above-mentioned requirements substantially.

Water factory's tradition conventional treatment process mainly is at settling basin front end dosing coagulant so that water-borne glue attitude particle takes off surely, through cohesion, flocculation, precipitation, removes the contaminant particles in the water, reduces raw water turbidity; Chlorination and back chlorination before water factory's chlorination technology generally is divided into, preceding chlorination carried out before Yuan Shui enters settling basin, and its fundamental purpose is the organism in oxidation and the former water of degraded, kills algae in the water simultaneously, avoids it to grow in settling basin and filter tank; Back chlorination carries out chlorination in clear water reserviors, make to keep certain density chlorine residue in the output water, thereby assurance tap water terminal user water quality is never degenerated.

Water factory's tradition conventional treatment process mainly is to remove suspended particle, colloidal material and bacterium in the water, and this technology was used more than 100 year by the countries in the world continuity.Yet, since China's reform and opening-up, on the one hand along with high speed development, the urbanization paces of industrial or agricultural are accelerated, some local governments GDP growth that often covets, be negligent of environment supervision, protection and improvement, cause many cities, the situation that the water source that especially is positioned at the downstream river city is subjected to polluting with eutrophication is just progressively deepened, the continuous deterioration of raw water quality; The increasing of dissolved organic matter in the contaminated former water makes common process obviously descend to the removal effect of water pollutant; On the other hand, along with the raising of people's living standard, numerous citizen are more and more higher to the requirement of potable water.For this reason, the cities and towns water factory that an urgent demand raw water quality is lower than the III class increases advanced treatment process on traditional conventional treatment process basis, to improve effluent quality.Ozone-biological activated carbon advanced treatment process is at first developed by Germany and in developed country's widespread uses such as America and Europe, Japan.The strong oxidizing property of ozone and the absorption of activated charcoal and degradation characteristic make this technology to hardly degraded organic substance in the potable water good treatment effect be arranged.Experimental study and the large-scale application result of water factory all show, behind common process, increase " ozone-active carbon " advanced treatment process, not only can remove the organism in the water, can also remove iron in the water, manganese, colourity etc., improve the security and the biological stability of water.China a few cities water factory also begins to increase this advanced treatment process of employing on traditional conventional treatment process basis.

Replace preceding chlorination with pre-ozone, the tentatively organism in the oxygenolysis water and other reducing substances, and can remove algae, promote flocculation, reduce the flocculating agent consumption, reduce the turbidity for the treatment of drainage, improve filter velocity and prolong filter cycle, reduce the water quality of filtering the back flush water yield, improving the sand filtration water outlet.Increased main ozone and bioactive carbon link behind sand filter, wherein main ozone purpose is sterilization and will be difficult to biodegradable organism chain rupture, open loop in the water effectively, improves organic biodegradability and adsorbability in the former water; Biological activated carbon relies on the absorption and the biomembranous degradation on surface that organism is removed.

Main ozone and activated charcoal are the key links of entire depth treatment process, and the quality that main ozone adds quality directly has influence on the treatment effect of this link.Keep under the stable case at raw water quality, ozone adds control system can be approximately a ratio control system, is the basis that ozone adds control continuously so obtain the real-time flow of inlet water of ozone contact tank continuously.If the flow of inlet water of ozone contact tank can not be surveyed, then be difficult to realize ratio control; Simultaneously, the ozone contact tank flow of inlet water can not survey and the time become then mean ozone add control procedure time delay the unknown and the time become; In addition, the variation of ozone contact tank flow of inlet water also directly influences static gain and other parameters of model in the after-odour oxygen change procedure, therefore obtains the ozone contact tank real-time traffic continuously ozone is added very key of the accurate control of enforcement.

When research object of the present invention---phase city water factory of Suzhou City Running-water Company increases the transformation of " ozone-active carbon " advanced treatment process behind common process, owing to be subjected to the restriction of environment and pipeline configuration can't be installed in linear flow rate meter (also there will be this difficulty usually in the traditional common process of the former employing in the many cities and towns of China water factory when increasing the transformation of " ozone-active carbon " advanced treatment process from now on behind common process), thereby can't onlinely record ozone contact tank water inlet real-time traffic in lift pump room water outlet place before the ozone contact tank.Be responsible for the ozone dosing system supply of material of Suzhou City phase city water factory of Running-water Company, install, the German WEDECO engineering technical personnel of company of debugging, after the responsible person of city water factory confers mutually with Suzhou City Running-water Company, the flow of inlet water of the online flowmeter flow of the outlet of subsequent technique activated carbon filter as ozone contact tank, the activated carbon filter level fluctuation exists the superposition influence to the rate of discharge of carbon filtering pool, especially significantly change (as one in operating mode, two pump house switch cars and carbon filtering pool back flush) carbon filtering pool exists level fluctuation very big under the situation, the online flowmeter flow of the outlet of subsequent technique activated carbon filter very large deviation will be occurred as the flow of inlet water of ozone contact tank, thereby cause ozone to add the control misalignment, have a strong impact on the water stabilization of dispatching from the factory.

Though, water pump production firm can provide water pump rated flow curve in range of lift usually to the water pump that dispatches from the factory, but the water pump that water factory moves all the year round will cause the skew of rated flow performance curve in its range of lift inevitably owing to there are problems such as turbo blade weares and teares, the main shaft wearing and tearing are loosening; Supply water and can not interrupt in view of water factory again, thus do not allow to water pump dismantle, off-line testing and its flow performance curve carried out determined off-line.

Summary of the invention

Goal of the invention: the present invention is according to the process conditions of research water factory, water factory was subjected to the restriction of environment and pipeline configuration usually when the traditional common process of the solution many former employings of China water factory increased the transformation of " ozone-active carbon " advanced treatment process behind common process, can't lift pump room 2 water outlets place before ozone contact tank be installed in the linear flow rate meter, can not the on-line measurement ozone contact tank problem of water inlet real-time traffic, proposition utilizes lift pump room 2 (variable frequency control) water flow before the ozone contact tank water inlet to calculate the soft experiment with measuring and the measuring method of the flow of inlet water of ozone contact tank in real time, thereby provides the flow of inlet water data of ozone contact tank accurately for thereafter ozone adds optimal control.

Technical scheme:

The present invention adopts following technical scheme for solving above technical matters:

The online soft sensor method of a kind of water factory ozone contact tank flow of inlet water comprises the steps:

The water inlet of (I) step, ozone contact tank promotes work online test procedure under the condition of water pump, obtains respectively and promotes water pump at actual maximum functional lift H _MaxWith actual minimum work lift H _MinUnder frequency-flow corresponding relation curve:

(1) promotes water pump at actual maximum functional lift H _MaxUnder frequency-flow corresponding relation curve acquisition step:

Step 1 will be set in minimum permission liquid level L in conjunction with the liquid level of well _MinThe place also promptly promotes water pump at actual maximum functional lift H _MaxFollowing operation;

Step 2 is closed tested lifting water pump, and the running frequencies of fixing other lifting water pumps are constant, wait for when the carbon filtering pool water flow is stablized, and read the online flow value Q of carbon filtering pool water outlet _Origin

Step 3 is opened tested lifting water pump and with running frequency f _sBe adjusted to 58%f _Max, wait for that the carbon filtering pool water flow is stable;

Step 4 reads the online flow value Q of carbon filtering pool water outlet _oAnd each charcoal filter divides the liquid level change amount Δ L in pond _j, ozone contact tank flow of inlet water Q _i=Q _o-Δ Q, the carbon filtering pool water flow variable quantity that causes for the carbon filtering pool level fluctuation of Δ Q wherein, $\mathrm{\ΔQ}=\frac{\left(\underset{j=1}{\overset{n}{\mathrm{\Σ}}}\mathrm{\Δ}{L}_j\right)\×S}{\mathrm{\Δt}},$ N is a charcoal filter branch pond number, and S is the cross-sectional area in each charcoal filter branch pond, and Δ t is a timing statistics; Δ L _jWith Q _oBe the results that organize after the continuous coverage values are passed through filtering and are averaged processing more; Calculate tested lifting water pump operation frequency f _sBe 58%f _MaxThe time water flow value Q _t=Q _i-Q _Origin

Step 5 is with the running frequency f of tested lifting water pump _sIncrease 5%f successively _Max, wait for the carbon filtering pool water flow stable after execution in step 4 once more, increase repeatedly 8 times altogether, until the running frequency f of tested lifting water pump _sGreater than 98%f _Max, enter step 6;

Step 6, the frequency f of 9 groups of tested lifting water pumps that above step is recorded _sWith flow value Q _tAdopt the method for curve fit to obtain tested lifting water pump at actual maximum functional lift H _MaxUnder frequency-flow corresponding relation curve.

(2) promote water pump at actual minimum work lift H _MinUnder frequency-flow corresponding relation curve acquisition step:

Steps A will be set in the highest permission liquid level L in conjunction with the liquid level of well _MaxThe place also promptly promotes water pump at actual minimum work lift H _MinFollowing operation;

Step B～step F adopts that middle step 2～the described method of step 6 is identical with (one).

(II) step, record ozone contact tank water inlet and promote water pump work at present lift H _Real, the lifting water pump that obtains in conjunction with (I) step is at H _MaxAnd H _MinFrequency under the condition-flow corresponding relation curve adopts the method for linear interpolation and curve fitting to obtain to promote water pump work at present lift H _RealUnder frequency-flow corresponding relation curve, inquire about this curve current running frequency f of water pump that gets a promotion automatically _RealUnder real-time traffic, when many lifting water pump parallel runnings, then the lifting water pump real-time traffic sum of many parallel runnings is the ozone contact tank flow of inlet water.

Described approach based on linear interpolation as shown in the formula:

$Q_{H\_\mathrm{real}}=Q_{H\_\max }+\frac{(H_{\mathrm{real}}-H_{\min })\×(Q_{H\_\min }-Q_{H\_\max })}{(H_{\max }-H_{\min })}---\left(1\right)$

In the following formula: H _RealRepresent the work at present lift of tested lifting water pump;

H _MaxRepresent the actual maximum functional lift of tested lifting water pump;

H _MinRepresent the actual minimum work lift of tested lifting water pump;

Q _{H_real}Represent tested lifting water pump that interpolation gets at work at present lift H _RealUnder the water flow value;

Q _{H_min}Represent tested lifting water pump at actual minimum work lift H _MinUnder the water flow value;

Q _{H_max}Represent tested lifting water pump at actual maximum functional lift H _MaxUnder the water flow value.

Beneficial effect:

The present invention is applicable to the running frequency that promotes water pump and the work lift can be surveyed and technological process in have the soft measurement of water factory's ozone contact tank flow of inlet water under the associated reference flow situation, also be applicable to simultaneously the soft measurement of discharge under the similar operating mode, its major technique characteristics are: method is practical reliable, not needing increases any extra cost, has extensive applicability.

Description of drawings

Fig. 1 is conventional drinking water treatment process chart;

Fig. 2 is routine+" ozone-active carbon " advanced treatment process process flow diagram;

Fig. 3 promotes water pump frequency-online test technology scene photo of flow corresponding relation curve;

Fig. 4 promotes water pump frequency-online test method schematic flow diagram of flow corresponding relation curve;

Among the figure: L _MinRepresentative is in conjunction with the minimum permission liquid level of well; H _MaxRepresentative is in conjunction with the highest permission liquid level of well;

f _sRepresent the running frequency of tested lifting water pump; f _MaxRepresent the maximum frequency of operation of tested lifting water pump;

τ represents the one order inertia system time constant;

Q _OriginCarbon filtering pool water flow when tested lifting water pump is closed in representative; Q _oRepresent the carbon filtering pool water flow;

Q _iRepresent the ozone contact tank flow of inlet water; Δ L _jRepresent the liquid level change amount in each charcoal filter branch pond;

The carbon filtering pool water flow variable quantity that Δ Q representative is caused by the carbon filtering pool level fluctuation.

Fig. 5 promotes water pump water outlet flow soft measurement schematic flow diagram.

Fig. 6 is that 1# promotes the frequency-flow corresponding relation curve of water pump under actual maximum functional lift 6m in the embodiments of the invention.

1# promotes the frequency-flow corresponding relation curve of water pump under actual minimum work lift 5.6m in Fig. 7 embodiments of the invention.

1# promotes the frequency-flow corresponding relation curve of water pump under real-time working lift 5.85m in Fig. 8 embodiments of the invention.

Embodiment

Technical scheme of the present invention is elaborated at thread test below in conjunction with reality in phase city water factory of Suzhou City Running-water Company:

As shown in Figure 2, the water inlet of water factory ozone contact tank is that the lift pump room 2 by the front promotes the back gravity flow and forms, and lift pump room 2 is common often to have many lifting water pumps in parallel or intermittently take turns to operate.Lift pump room 2 will rise in the ozone contact tank in conjunction with the water in the well, so the flow of inlet water of ozone contact tank also is total water flow of lift pump room 2.

After the ozone contact tank is activated carbon filter, and the exit of activated carbon filter is equipped with online flowmeter.Ease up, do not have pump house switch car at flow rate of water flow and significantly under the steady working condition of regulating frequency, the flow of inlet water that can go out ozone contact tank according to the water flow and the level fluctuation approximate treatment of activated carbon filter, thus the reference flow of water pump frequency-flow corresponding relation curve promoted as identification.

The first step is carried out the on-line testing test to promoting water pump frequency-flow corresponding relation curve, and its technology scene as shown in Figure 3.Lift pump room 2 has 6 lifting water pump parallel runnings, and wherein 42 of work are standby, therefore need carry out the on-line testing test one by one to 6 lifting water pumps.Designed elevation in conjunction with well is 7.1m, and the highest permission liquid level is 1.5m, and minimum permission liquid level is 1.1m.Therefore the actual minimum work lift of the lifting water pump in the lift pump room 2 is 5.6m (the designed elevation 7.1m in conjunction with well deducts in conjunction with the highest permission liquid level of well 1.5m), and actual maximum functional lift is 6m (the designed elevation 7.1m in conjunction with well deducts in conjunction with the minimum permission liquid level of well 1.1m).

As shown in Figure 4, the concrete steps that the 1# lifting water pump on-line testing of lift pump room 2 is tested are as follows:

(1) obtain the frequency-flow corresponding relation curve of lifting water pump under actual maximum functional lift 6m:

Step 1 will be set in the 1.1m place in conjunction with the liquid level of well;

Step 2 is closed 1# and is promoted water pump, and the running frequency of the lifting water pump of other three work is set at 90%f _Max, wait for when the carbon filtering pool water flow is stablized that reading the online flow value of carbon filtering pool water outlet this moment is Q _Origin

Step 3 is opened 1# and is promoted water pump and running frequency is adjusted to 58%f _Max, wait for that the carbon filtering pool water flow is stable;

Step 4 reads the online flow value Q of carbon filtering pool water outlet of this moment _oAnd each charcoal filter divides the liquid level change amount Δ L in pond _jAnd calculate 1# thus and promote the flow value Q of water pump when current running frequency _t

Step 5 judges that whether 1# promotes the running frequency of water pump less than 98%f _MaxIf, less than 98%f _MaxThe running frequency that then 1# is promoted water pump increases 5%f _Max, wait for that the carbon filtering pool water flow jumps to step 4 after stable; If greater than 98%f _MaxThen execution in step 6;

Above test procedure records 58%f _Max-98%f _MaxBetween 9 class frequencys-flow value as shown in the table:

Step 6 is carried out least square curve to the discrete value in the last table and is fitted, and obtains 1# and promotes the frequency-flow corresponding relation curve of water pump under actual maximum functional lift 6m, as shown in Figure 6.

For the additional explanation in the step 3:

(1) about running frequency is adjusted to 58%f _MaxExplanation.The general water pump that promotes directly arrives 50%f with frequency adjustment when turn on pump _MaxMore than, on the one hand because frequency is too low to make water pump that rotating speed is arranged easily and do not have the flow can not normal water supply, and increase pipe resistance, might damage water pump in the time of serious; The water pump frequency is too low on the other hand makes that the power consumption of water outlet is lower than too, thereby seriously not energy-conservation; The present invention directly is adjusted to 58%f for the sake of assurance _Max

(2) about the stable explanation of carbon filtering pool water flow.Because most of industrial process object are first-order system, the transport function that is located at the thread test object is $G\left(s\right)=\frac{k}{1+\mathrm{\τs}},$ Wherein can record its timeconstant (output quantity rises to 63.2% required time of steady-state value) by step response test, usually get on the engineering 4 τ as response time of system (during 4 τ the output quantity of system reached steady-state value 98.2%), therefore tested lifting water pump operation frequency setting to waited for that at least 4 τ times could guarantee that the carbon filtering pool water flow was basicly stable after well.

(2) obtain the frequency one flow corresponding relation curve of lifting water pump under actual minimum work lift 5.6m:

To be set in 1.5m in conjunction with the well liquid level, and repeat above (one) middle step 2-step 6 and can obtain the frequency-flow corresponding relation curve of 1# lifting water pump under actual minimum work lift 5.6m, as shown in Figure 7.

The 1# that the above test of following basis obtains promotes the frequency-flow corresponding relation curve of water pump under 6m and 5.6m, and under operate as normal, record in conjunction with well liquid level 1.25m, the real-time water flow that 1# is promoted water pump calculates, its exemplary flow as shown in Figure 5, concrete steps are as follows:

Step 1 promotes the frequency-flow corresponding relation curve of water pump under 6m and 5.6m to 1# and samples, and sampled value is as shown in the table:

Step 2, it is as follows that the sampled value in the last table is carried out the discrete form of frequency flow that linear interpolation obtains under the real work lift 5.85m:

Step 3 is carried out least square curve to the discrete value in the last table and is fitted, and obtains 1# and promotes the frequency-flow corresponding relation curve of water pump under real-time working lift 5.85m, as shown in Figure 8.

Step 4 is inquired about the curve among the last figure, can obtain real-time water flow (as: inquiry curve, frequency 86%f that 1# promotes water pump _MaxThe corresponding flow value is 920m ³/ h).

Adopt identical method can obtain the real-time water flow (standby as if current 4#, 5# then is zero) of 2#-6# lifting water pump, 1#-6# promotes the flow of inlet water that the real-time water flow sum of water pump is ozone contact tank.

Claims (3)

1. the online soft sensor method of water factory's ozone contact tank flow of inlet water is characterized in that: comprise the steps:

The water inlet of (I) step, ozone contact tank promotes work online test procedure under the condition of water pump, obtains respectively and promotes water pump at actual maximum functional lift H _MaxWith actual minimum work lift H _MinUnder frequency-flow corresponding relation curve;

(II) step, record ozone contact tank water inlet and promote water pump work at present lift H _Real, the lifting water pump that obtains in conjunction with (I) step is at H _MaxAnd H _MinFrequency under the condition-flow corresponding relation curve adopts the method for linear interpolation and curve fitting to obtain to promote water pump work at present lift H _RealUnder frequency-flow corresponding relation curve, inquire about this curve current running frequency f of water pump that gets a promotion automatically _RealUnder real-time traffic, when many lifting water pump parallel runnings, then the lifting water pump real-time traffic sum of many parallel runnings is the ozone contact tank flow of inlet water.

2. the online soft sensor method of water factory as claimed in claim 1 ozone contact tank flow of inlet water is characterized in that: the described approach based on linear interpolation of (II) step as shown in the formula:

$Q_{H\_\mathrm{real}}=Q_{H\_\max }+\frac{(H_{\mathrm{real}}-H_{\min })\×(Q_{H\_\min }-Q_{H\_\max })}{(H_{\max }-H_{\min })}---\left(1\right)$

In the following formula: H _RealRepresent the work at present lift of tested lifting water pump;

H _MaxRepresent the actual maximum functional lift of tested lifting water pump;

H _MinRepresent the actual minimum work lift of tested lifting water pump;

Q _{H_real}Represent tested lifting water pump that interpolation gets at work at present lift H _RealUnder the water flow value;

Q _{H_min}Represent tested lifting water pump at actual minimum work lift H _MinUnder the water flow value;

Q _{H_max}Represent tested lifting water pump at actual maximum functional lift H _MaxUnder the water flow value.

3. the online soft sensor method of water factory as claimed in claim 1 ozone contact tank flow of inlet water is characterized in that: it is specific as follows that the water inlet of (I) step, ozone contact tank promotes the test procedure that water pump works online under the condition:

(-) promotes water pump at actual maximum functional lift H _MaxUnder frequency-flow corresponding relation curve acquisition step:

Step 1 will be set in minimum permission liquid level L in conjunction with the liquid level of well _MinThe place also promptly promotes water pump at actual maximum functional lift H _MaxFollowing operation;

Step 2 is closed tested lifting water pump, and the running frequencies of fixing other lifting water pumps are constant, wait for when the carbon filtering pool water flow is stablized, and read the online flow value Q of carbon filtering pool water outlet _Origin

Step 3 is opened tested lifting water pump and with running frequency f _sBe adjusted to 58%f _Max, wait for that the carbon filtering pool water flow is stable; f _MaxRepresent the maximum frequency of operation of tested lifting water pump;

Step 4 reads the online flow value Q of carbon filtering pool water outlet _oAnd each charcoal filter divides the liquid level change amount Δ L in pond _j, ozone contact tank flow of inlet water Q _i=Q _o-Δ Q, the carbon filtering pool water flow variable quantity that causes for the carbon filtering pool level fluctuation of Δ Q wherein,

N is a charcoal filter branch pond number, and S is the cross-sectional area in each charcoal filter branch pond, and Δ t is a timing statistics; Δ L _jWith Q _oBe the results that organize after the continuous coverage values are passed through filtering and are averaged processing more; Calculate tested lifting water pump operation frequency f _sBe 58%f _MaxThe time water flow value Q _t=Q _i-Q _Origin

Step 5 is with the running frequency f of tested lifting water pump _sIncrease 5%f successively _Max, wait for the carbon filtering pool water flow stable after execution in step 4 once more, increase repeatedly 8 times altogether, until the running frequency f of tested lifting water pump _sEqual 98%f _Max, enter step 6;

Step 6, the frequency f of 9 groups of tested lifting water pumps that above step is recorded _sWith flow value Q _tAdopt the method for curve fit to obtain tested lifting water pump at actual maximum functional lift H _MaxUnder frequency-flow corresponding relation curve;

(2) promote water pump at actual minimum work lift H _MinUnder frequency-flow corresponding relation curve acquisition step:

Steps A will be set in the highest permission liquid level L in conjunction with the liquid level of well _MaxThe place also promptly promotes water pump at actual minimum work lift H _MinFollowing operation;

Step B～step F adopts the middle method that step 2～the described method of step 6 is identical with ().

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