JPS6240668B2 - - Google Patents

Description

[Detailed description of the invention]

(1) Field of Application of the Invention The present invention is directed to identifying the emission sources of pollutants that are thought to be the cause of locally generated high concentration air pollution, and to detect the pollution of the identified emission sources in the high concentration area. The present invention relates to a method of providing a means for effectively implementing air pollution control by calculating material load contribution rates. (2) Prior art Regarding emission source regulation to prevent air pollution,
The total emission control method for sulfur oxides proposed by the Environment Agency in 1975 and currently being implemented by local governments is expected to be the most effective control measure for the time being. However, since the above-mentioned total emission regulation method determines the emission regulation value based on the annual average predicted value, depending on topographical and weather conditions, local and short-term ( (daily or hourly average), there is a possibility that there will be areas that exceed environmental standards. In order to deal with such localized and short-term high-concentration pollution, it is necessary to formulate simpler and more flexible regulatory measures, but the total amount control calculation requires a huge amount of calculations, making it difficult to implement flexible regulations. There were problems that were difficult to deal with. (3) Purpose of the invention The present invention eliminates the above problems, identifies pollutant emission sources that contribute to localized and short-term high concentration pollution, and The purpose of this study is to provide a method that is simpler than total amount regulation calculations and allows air pollution regulations to be operated more effectively and flexibly by calculating the contribution rate of pollutant loads to air pollution. (4) General description of the invention In order to achieve the above object, the present invention includes an advection path estimating section, an on-route pollutant emission amount estimating section, a pollutant concentration estimating section, a compatibility determining section, and a pollution contribution rate calculating section. There are five processing parts. (5) Examples Hereinafter, the present invention will be explained in detail with reference to examples. FIG. 1 shows the air pollution factor estimation method according to the present invention in the form of a block diagram, including a meteorological data input section 10, a route estimation section 11, an on-route pollutant emission amount estimation section 12, and a pollutant concentration estimation section. 13, a compatibility determining section 14, a parameter changing section 15, and a contamination contribution rate calculating section 16. The meteorological data input unit 10 is for periodically inputting wind direction WD and wind speed WS data measured at air pollution data observation stations scattered within the target area.In actual equipment, it is a magnetic tape device. , card/tape reader, etc. This wind direction
The WD and wind speed WS may be such as long as the east-west component W _EW and the north-south component W _SN of the wind speed can be calculated based on this data. The route estimation unit 11 selects a predetermined analysis target point (point of high concentration pollution X _A , time T _A ).
The advection path L of the air mass reaching the air mass is calculated based on observation station measurement data obtained from the meteorological data input unit 10. Here, X _A = (x _A , y _A ), and x
_A and y _A are coordinate values of orthogonal coordinates having the same origin as the coordinates X _s =(x _s , y _s ) regarding the pollutant emission source s, which will be described later. Further, L is a vector of the position of the air mass at each time, and its elements are coordinates (advection path points) on the orthogonal coordinates that also share the origin. The advection path L is determined by the following method. _The advection velocity _of the air mass at _{time TA} at _{the analysis} point W _EW , W _SN ) using the following formula. W _EW (T _A ), W _SN (T _A ): east-west component and north-south component of the wind speed at time T _A , where M: number of observation stations xobi, yxbi: coordinates of the i-th observation station. Suppose that an air mass above x _A flows with this advection speed, and the position of the air mass X (T _A −
Δt) is determined by the following equation. X( _TA −Δt) =X _A −u〓(X _A , T _A )・Δt (1) However, X( _TA −Δt)=(X _A ( _TA −Δt), y _A
( _TA - Δt)) indicates the coordinate position at time TA - _Δt of an air mass that was on X _A at time _TA . Next, the advection velocity u〓(X( _TA -Δt), T _A -Δt) at point X ( _TA - Δt) and time TA _- Δt is determined by calculation similar to the above formula (0), Based on this, the position of the air mass 2Δt hours ago is determined. By repeating this sequentially, the time point to be analyzed (X _A , T
The advection path of the air mass reaching _A ) can be determined. That is, the advection path point sequence X(·) is determined by the following equation. Here, N is the number of advection path calculation points, which is given by the following equation from the path point-to-point time Δt and the total time T _T of the advection path. N=T _T /Δt (3) The time T _T is arbitrary, but in view of the diurnal periodicity of changes in contaminant concentration, the longest time may be 24 hours. Advection path L of the air mass determined by the path estimation unit 11
is given to the on-route pollutant emission amount estimating section 12. The route pollutant emission amount estimating unit 12 calculates the above route L and the emission source (S) that has been investigated and recorded in advance.
Pollutant emissions by time (T) Q(S・
T), and the coordinates X _s of each S as input, the path L
Identify the above pollutant emission source and also find the pollutant emission amount Ql. For example, consider a certain route point L _i . The emission source on this route point _Li is defined as an emission source that exists within a predetermined air mass size AP centered on the route point coordinates. Then, the pollutant emission amount Q _Li on the route point is calculated as the sum of the emission amounts of the on-route emission sources S _Li using the following formula. Q _Li = ΣQ (S _Li , T _Li ) (4) By performing the above procedure for each route point, the emissions on the route point {Q (X _A , T _A ), Q (X (T _A −Δt) , T _A −Δt), ..., Q(X(TA _−NΔt ), T _A −NΔt)} can be estimated. The on-route pollutant emission amount obtained by the on-route pollutant emission amount estimating section 12 is calculated by the pollutant concentration estimating section 13.
becomes the input. The pollutant concentration estimation unit 13 is a part that estimates the pollutant concentration at the end of the advection path by recursive calculation. Assuming that the diffusion phenomenon inside and outside the air mass during time Δt is expressed by a certain function f, the concentration of the air mass C(t+Δt) after time Δt is as follows: C(t+Δt)=f(K, C(t), Q(t),
t) It can be expressed as (5). where K means the reaction parameter, C(t) is the air mass concentration before diffusion, Q(t)
is the amount of pollutants discharged on the route at time t. As this function f, for example, f(K, C(t), Q(t), t+Δt) = ∂/∂ZKz∂C(t)/∂Z+Q(t)−K _H C(t
)(6) is possible. Here, K _z : Vertical diffusion coefficient, K
_H : Horizontal diffusion coefficient. At this time, K _z and K _H are
Past experience values may be used. The pollutant concentration estimating unit 13 recursively calculates equation (5) by giving the initial value (I _v ) (air mass concentration at the starting point of the advective route) and inputting the pollutant discharge amount (Ql) on the route. Then, the estimated pollutant concentration C _S at the end point of the route is determined. At this time, the initial value I _v may be spatially interpolated from the actual concentration measured at each observation point in the area, and if the route is long enough or starting from a point where the environmental concentration is low, It is safe to assume that it is zero. The estimated concentration C _S at the end point of the route estimated by the pollutant concentration estimating section 13 is input to the compatibility determining section 14 and compared with the actually measured concentration C ₀ . If the compared results are within the predetermined error range Δc, then the formula
Each parameter K in (5) is sent to the pollution contribution rate calculation unit 16, and a pollution contribution vector D is calculated (details based on a specific example will be described later). However, since K is appropriately determined based on past experience, the estimated value and the measured value of the contamination concentration may not match. At this time, the parameter K is changed by the parameter changing section 15. In this case, an optimization method such as the steepest slope method may be used by looking at the degree of error between the actual measured value and the estimated value. Most simply, the direction of change in K can be determined by looking at the sign of the error between the measured value and the estimated value, and the width of change in K can be determined depending on the degree of the error. This suitability determination is continued until the error falls within the allowable range, but the steepest slope method may be used for changing the parameter K from the second time onwards. in this case,
The modification ΔK is obtained by the following equation. ΔK=(C ₀ −C ₂ )・(K ₂ −K ₁ )/C ₂ −C ₁
(7) Here, C ₀ is the measured concentration, C ₁ is the estimated concentration at the first attempt, C ₂ : estimated concentration at the second attempt, K ₁ , K ₂ : the first and second attempts. This is the parameter value at the time. After changing the parameters in this way, the pollutant concentration estimating unit 13 performs recursive calculation using the changed parameters,
The resulting estimated value C _S is compared with the actual measured value in the suitability determination section 14 . The above procedure is continued until the comparison result falls within the allowable range, and as a result, the final parameter K is determined. The pollution contribution rate calculation unit 16 creates a pollution contribution vector between each route point and the route end point (point where high concentration pollution occurs) based on the parameter K determined by the above procedure. D below is an example of this contamination contribution vector.

【table】

[Table] This can be easily obtained by recursively calculating equation (5) assuming that a unit amount is discharged at each route point. The process of determining the pollution contribution vector D from the parameter K will be specifically described below. Among the route points 1 to X _A , when the final route point X _A is the point where high concentration pollution occurs, the route point M (M=
1,...,X _A -1), the elements of the vector D corresponding to The amount that indicates how _much of the contamination remains at the route _point This is the degree of contribution (hereinafter referred to as Cx ^M _A ) that indicates whether the Note that the element of the vector D at the final route point X _A is the contribution of X _A itself, and becomes 0 if no pollutants are discharged from X _A. Next, an example will be described in which each element of the vector D is obtained by performing a recursive operation by continuously applying equation (5). First, equation (5) expresses how the pollution concentration C(t) of the air mass at the current time t changes after a time Δt depending on the amount of pollutants discharged Q(t). Here, the contribution of route point M to X _A (Cx ^M _A ) where Q(t) is the unit discharge amount 1 and Δt is the unit time 1
The recursive operation of equation (5) in the sequence to obtain is as follows. At route point M, if C(t)=0, Q(t)=1, then C ^M _M =1, so C ^M _M+1 = C(t+1) = f(K, C(t), Q( t), t)=f
(K,0,1,t) C ^M _M+2 =C(t+2) =f(K,C(t+1),1,t) =f(K,f(K,0,1,t),1,t )
=f(K,C ^M _M+1 ,1,t) 〓 〓 Cx ^M _A =C(t+X _A -1) =f(K,f(K,Cx ^M _A-2 ,1,t) =f(K, Cx ^MA _-1 , 1, t) The contamination contribution vector D obtained in this way
Using the following equation, the load amount W and the contribution rate γ at the high concentration pollution occurrence point are calculated for each emission source on the route L, which has already been determined by the on-route pollutant estimating unit 12. W=D・P (8) γ=W/C ₀ (9) Here, W is the pollution load for each emission source, D is the pollution contribution vector, the size is 1×N, and P is the N-dimensional vector. Among the emission sources in the target area, the emissions of only those identified as emission sources on route points are considered as elements. Calculations of equations (8) and (9) can be performed for each emission source identified as a point-on-route emission source within the target area, and each emission source has a concentration at the high concentration point X _A. It becomes clear how much contribution is being made. By outputting the above results in the form of a ledger or the like, it is possible to identify the emission sources contributing to the high concentration at the specified analysis target point, and also to know the contribution rate of each emission source. (6) Effects of the invention As explained above, according to the present invention, it is possible to quantitatively clarify the causal relationship of pollution occurrence, such as which emission sources and how much they contribute to the pollution concentration at a given point. becomes possible. In addition, an accurate contribution relationship can be given by changing parameters based on actually measured concentrations. The time required to calculate the contribution rate is short, making it possible to implement air pollution regulations flexibly and effectively, as well as identifying emission sources that contribute significantly to high-concentration pollution.
It becomes possible to guarantee the equality of regulations.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the overall configuration of the present invention.

Claims (1)

[Claims] 1. From wind direction and wind speed data measured at multiple locations within the target area at regular intervals, the advection path of the air mass reaching the point of high concentration pollution is estimated, and the estimated advection path and emission sources within the target area are estimated. The emission sources at multiple route points on the advective route are identified from the position information of From the pollutant diffusion parameters determined based on past experience and the total amount of pollutant discharge on the advection route, the pollution concentration at the high concentration pollution occurrence point corresponding to the end point of the advection route is estimated, and the estimated pollution concentration is calculated. and a contamination concentration that has been actually measured in advance, and when the difference value exceeds a predetermined tolerance value, the parameter is changed according to the difference value, and the contamination concentration is adjusted based on the changed parameter. It is characterized by repeating the estimation process and using the parameters when the difference value becomes below a tolerance value to calculate the pollution contribution rate to the pollution concentration at the end point of the advection route for each emission source on the advection route. A method for estimating air pollution factors.