Environmental risk assessment method for bulk industrial solid waste storage yard

Abstract

The invention discloses a bulk industrial solid waste storage yard environment risk assessment method, and relates to the technical field of solid waste risk assessment. Comprising the steps of screening and establishing an environment risk assessment index system based on natural environment characteristics and influence factors of a solid waste storage yard; determining the index weight of each level of the environmental risk assessment index system, and performing grading quantification processing on part of non-quantitative indexes; solid waste storage yard environment risk evaluation index grading and scoring standards are formulated; and on the basis of the determined index weight of each level, comparing with the formulated environmental risk evaluation index grading and scoring standard, evaluating the environmental risk of the solid waste storage yard by using a sampling fuzzy evaluation method, calculating to obtain a risk evaluation score, and determining the environmental risk level. The method is high in universality, makes up for the deficiency of an industrial solid waste storage yard environment risk assessment method, and provides reference for subsequent research and formulation of a comprehensive and comprehensive bulk industrial solid waste storage yard environment pollution risk grading evaluation and management method.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of risk assessment of solid waste, and particularly relates to a method for environmental risk assessment of bulk industrial solid waste yard. BACKGROUND

[0002] Bulk industrial solid waste includes smelting slag, fly ash, coal gangue, tailings, red mud, slag, phosphogypsum and other industrial by-product gypsum, etc. In recent years, with the development of chemical industry, steel, coal, non-ferrous metal and other industries, the scale of industrial solid waste is expanding, and the cumulative storage of bulk solid waste is about 6x10 10 t, and the annual increase in storage is nearly 3x10 9 t. Due to the low utilization rate, a large number of industrial solid waste is randomly and improperly stacked, and illegal dumping occurs frequently, which not only wastes land and resources, but also brings potential environmental risks. These solid waste pollution sources have relatively large pollutant release potential, often containing lead, nickel, chromium, arsenic, mercury and other heavy metal elements, which flow into nearby rivers or seep into the ground, causing soil and groundwater pollution, and further threatening the health of people around.

[0003] There are many complex factors affecting the environmental risk of solid waste pollution sources, and they interact with each other. The difficulty lies in directly quantifying the risk. Some existing evaluation technical specifications for specific scenarios of solid waste yard mainly make simple grade division or weight assignment from the aspects of solid waste yard characteristics, surrounding environmental sensitivity, control mechanism reliability, etc., and then make a comprehensive score. At present, the research on solid waste risk assessment mainly focuses on the environmental pollution evaluation of soil and groundwater of some specific type of solid waste yard or the quantitative or semi-quantitative human health risk evaluation in a specific link. Based on the monitoring data of the site, the risk index of the graded object is obtained according to the specific scoring principle, and then the size of the environmental pollution risk or human health risk is evaluated. The existing evaluation technical specifications or evaluation method system generally perform single type evaluation, and the universality is relatively poor. In the process of building the evaluation system, the influence of different environmental factors and operating conditions of the yard on the environmental risk is ignored or neglected. There is no corresponding evaluation mechanism to comprehensively evaluate the solid waste pollution source, and there is no recognized evaluation method, which is not conducive to the risk control and grading management of solid waste yard.

[0004] Therefore, a method for environmental risk assessment of bulk industrial solid waste yard is proposed to solve the problems existing in the prior art, which is a problem urgently needed to be solved by the person skilled in the art. SUMMARY

[0005] Therefore, the present application provides a method for evaluating environmental risk of a large industrial solid waste storage yard, which fully considers the natural environment characteristics and internal and external influencing factors of the solid waste storage yard, proposes an evaluation index system and a grading quantification method based on the three elements of source-path-receptor, and further proposes a method for determining the weight of each evaluation index.

[0006] To achieve the above object, the present application adopts the following technical solutions.

[0007] A method for evaluating environmental risk of a large industrial solid waste storage yard, comprising the following steps:

[0008] S1: screening and establishing an environmental risk evaluation index system based on the natural environment characteristics and influencing factors of the solid waste storage yard;

[0009] S2: determining the weight of each level index of the environmental risk evaluation index system and grading and quantifying some non-quantitative indexes;

[0010] S3: formulating grading and scoring standards for the environmental risk evaluation indexes of the solid waste storage yard;

[0011] S4: based on the weight of each level index determined in S2, referring to the grading and scoring standards for the environmental risk evaluation indexes formulated in S3, evaluating the environmental risk of the solid waste storage yard by using a sampling fuzzy evaluation method, calculating the risk evaluation score, and determining the environmental risk level.

[0012] Optionally, the environmental risk evaluation index system screened and established in S1 comprises two levels of indexes.

[0013] The first level indexes include solid waste characteristics, storage yard characteristics, and environmental characteristics.

[0014] The second level indexes of the solid waste characteristics include heavy metal Nemerow pollution index and acid-base property.

[0015] The second level indexes of the storage yard characteristics include storage amount, land area, service life, and anti-seepage form.

[0016] The second level indexes of the environmental characteristics include groundwater depth, annual rainfall, soil permeability of the vadose zone, soil permeability of the saturated zone, number of environmental sensitive points within 1km from the storage yard, population within 1km from the storage yard, distance between the storage yard and the nearest sensitive target, land use within 1km from the storage yard, and groundwater and surface water use within 1km from the storage yard.

[0017] Optionally, the heavy metal Nemerow pollution index is used for characterization, and the heavy metals copper, zinc, cadmium, lead, chromium, mercury, nickel, arsenic and inorganic fluoride in solid waste leaching toxicity are selected as the characterization parameters, and the calculation formula is as follows:

[0018]

[0019] In the formula, P 综 is the comprehensive pollution index; P imax is the maximum value of the single pollution index of heavy metal and fluoride pollutants, is the average value of the single factor pollution index of heavy metal and fluoride pollutants, C i is the leaching concentration of heavy metal and fluoride i, S i is the highest allowable emission limit value of heavy metal and fluoride i.

[0020] Optionally, the subjective and objective combination weighting method is used to determine the weight of each level index in the environmental risk assessment index system in S2;

[0021] The analytic hierarchy process is used to subjectively weight each index in the environmental risk assessment index system, and the entropy weight method is used to objectively weight each index in the environmental risk assessment index system, and based on the minimum sum of deviation, 50% of the subjective weight and the objective entropy weight are added as the final combined weight value.

[0022] Optionally, some non-quantitative indexes in S2 include anti-seepage form, land use mode, groundwater and surface water use, acid-base, soil permeability coefficient; wherein,

[0023] The anti-seepage form is classified and quantified according to five levels of no anti-seepage measures, simple soil greening, partial anti-seepage or loss at the bottom / top of the stockyard, single anti-seepage at the bottom / top of the stockyard, and perfect anti-seepage facilities, and the subsequent data processing is carried out according to the quantified scores;

[0024] The soil utilization mode is classified and quantified according to five levels of unused land, mining land, industrial land, residential and office land, agricultural land and protected area, and the subsequent data processing is carried out according to the quantified scores;

[0025] The groundwater and surface water use are classified and quantified according to five levels of non-use, industrial use, agricultural irrigation water, water supply source, domestic water and protected area, and the subsequent data processing is carried out according to the quantified scores;

[0026] The acid-base is classified and quantified according to five levels of pH value 6-9, 4.5-6 and 9-10, 3-4.5 and 10-11, 2-3 and 11-12.5, 0-2 and 12.5-14, and the subsequent data processing is carried out according to the quantified scores;

[0027] Soil permeability is based on a permeability coefficient value >10 -1 cm / s, 10 -1 ~10 -3 cm / s, 10 -3 ~10 -5 cm / s, 10 -5 ~10 - 7 cm / s, <10 -7 The five levels of cm / s are graded and quantified, and the subsequent data processing is carried out based on the quantified scores.

[0028] Optionally, scoring is performed according to the solid waste landfill environmental risk assessment index classification and scoring standard formulated in S3, and the higher the score value obtained, the greater the corresponding environmental risk.

[0029] Optionally, in S4, the environmental risk of the solid waste dump is evaluated using a sampling fuzzy assessment method, and a risk assessment score is calculated to determine the specific content of the environmental risk level:

[0030] S41: Taking the indicators in the environmental risk assessment indicator system as evaluation factors, an evaluation indicator system set U = {U1, U2, ..., U n}; Divide the environmental risk assessment results of solid waste dumps into m levels, and construct the evaluation set of sampling fuzzy evaluation method as V = {V1, V2, ..., V m}, where n is the number of indicators in the evaluation index system set, and m is the number of comments in the comment set;

[0031] S42: Based on the solid waste dump environmental risk assessment index classification and scoring standards formulated in S3, combined with the trapezoidal membership function, the membership degree of the single factor evaluation index to the comment set V is calculated, and the corresponding fuzzy evaluation matrix R is obtained:

[0032]

[0033] Where r ij is the membership degree of the i-th element of the evaluation index system set U to the j-th comment in the comment set V, i = 1, 2, 3...n, j = 1, 2, 3...m;

[0034] S43: The fuzzy evaluation matrix R and the weight vector W are operated according to the fuzzy operator to obtain the fuzzy evaluation set B of the solid waste dump environmental risk:

[0035] W={w1,w2,···,w n}

[0036]

[0037] S44: using a weighted average type fuzzy synthesis operator, the actual score S of risk evaluation is calculated:

[0038] S = BV T

[0039] By comparing the solid waste yard environmental risk score, the environmental risk level is determined.

[0040] Through the above technical solution, compared with the prior art, the present application provides a kind of bulk industrial solid waste yard environmental risk assessment method, with the following beneficial effects:

[0041] (1) the present application fully considers the natural environment characteristics and internal and external influencing factors of solid waste yard, proposes to use the evaluation index system and grading quantification method based on "source-path-receptor" risk three elements, and further proposes the method for determining the weight of each evaluation index, finally, the internal and external factors affecting environmental risk are analyzed and quantified by fuzzy comprehensive evaluation, the risk evaluation score is calculated, and the environmental risk level is determined;

[0042] (2) the present application has strong universality, makes up for the lack of industrial solid waste yard environmental risk assessment method, and provides reference for subsequent research and development of comprehensive and comprehensive bulk industrial solid waste yard environmental pollution risk grading evaluation and management method. BRIEF DESCRIPTION OF DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application or prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description are only part of the embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative labor on the basis of the provided drawings.

[0044] Figure 1 A bulk industrial solid waste yard environmental risk assessment method flow chart is provided for the present application.

[0045] Figure 2 An environmental risk assessment index system schematic diagram is provided for the present application. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present application will be described clearly and completely in the following with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0047] REFERENCE Figure 1As shown, the present application discloses a kind of bulk industrial solid waste yard environmental risk assessment method, comprising the following steps:

[0048] S1: based on the natural environment characteristics and influencing factors of solid waste yard, screening and establishing environmental risk assessment index system;

[0049] S2: determining the weight of each level index of environmental risk assessment index system, and grading and quantifying part of non-quantitative indicators;

[0050] S3: making solid waste yard environmental risk assessment index grading and scoring standard;

[0051] S4: based on the weight of each level index determined in S2, comparing with the environmental risk assessment index grading and scoring standard made in S3, using sampling fuzzy evaluation method to evaluate the environmental risk of solid waste yard, and calculating the risk evaluation score to determine the environmental risk level.

[0052] Further, the environmental risk assessment index system screened and established in S1 includes two levels of indexes;

[0053] The first level index includes solid waste characteristics, yard characteristics and environmental characteristics;Among them,

[0054] The second level index of solid waste characteristics includes heavy metal Nemerow pollution index and acidity and alkalinity;

[0055] The second level index of yard characteristics includes storage capacity, land area, service life and anti-seepage form;

[0056] The second level index of environmental characteristics includes groundwater depth, annual rainfall, vadose zone soil permeability, saturated zone soil permeability, number of environmental sensitive points within 1km around the yard, population within 1km around the yard, distance from the yard to the nearest sensitive target, land use within 1km around the yard and groundwater and surface water use within 1km around the yard.

[0057] Further, heavy metal Nemerow pollution index is used for characterization, and the characterization parameters are selected from heavy metals copper, zinc, cadmium, lead, chromium, mercury, nickel, arsenic and inorganic fluoride in solid waste leaching toxicity, and the calculation formula is as follows:

[0058]

[0059] P i =C i / S i

[0060] In the formula, P 综 is the comprehensive pollution index, P imax is the maximum value of single pollution index of heavy metal and fluoride pollutants, C is the average value of the single factor pollution index of heavy metal and fluoride pollutants i S is the leaching concentration of heavy metal and fluoride i elements i S is the leaching concentration of heavy metal and fluoride i elements

[0061] Further, the subjective and objective combination weighting method is used in S2 to determine the weight of each level index of the environmental risk assessment index system;

[0062] The analytic hierarchy process is used to subjectively weight each index in the environmental risk assessment index system, and the entropy weight method is used to objectively weight each index in the environmental risk assessment index system. Based on the minimum sum of deviation, 50% of the subjective weight and the objective entropy weight are added as the final combined weight value.

[0063] Further, some non-quantitative indicators in S2 include anti-seepage form, land use mode, groundwater and surface water use, acid-base, soil permeability coefficient; among them,

[0064] The anti-seepage form is classified and quantified into five levels according to no anti-seepage measures, simple soil greening, partial anti-seepage or loss at the bottom / top of the stockyard, single anti-seepage at the bottom / top of the stockyard, and perfect anti-seepage facilities. The subsequent data processing is carried out based on the quantified scores.

[0065] The land use mode is classified and quantified into five levels according to unused land, mining land, industrial land, residential and office land, agricultural land and protected area. The subsequent data processing is carried out based on the quantified scores.

[0066] The groundwater and surface water use is classified and quantified into five levels according to non-use, industrial use, agricultural irrigation water, water supply source, domestic water and protected area. The subsequent data processing is carried out based on the quantified scores.

[0067] The acid-base is classified and quantified into five levels according to pH value 6-9, 4.5-6 and 9-10, 3-4.5 and 10-11, 2-3 and 11-12.5, 0-2 and 12.5-14. The subsequent data processing is carried out based on the quantified scores.

[0068] The soil permeability is classified and quantified into five levels according to permeability coefficient value >10 -1 cm / s, 10 -1 -10 -3 cm / s, 10 -3 -10 -5 cm / s, 10 -5 -10 - 7 cm / s, <10 -7 cm / s. The subsequent data processing is carried out based on the quantified scores.

[0069] Further, according to the solid waste yard environmental risk assessment index classification and scoring standard formulated in S3, the higher the score value obtained is, the greater the corresponding environmental risk is.

[0070] Further, the solid waste yard environmental risk is evaluated by using the sampling fuzzy evaluation method in S4, and the risk evaluation score is calculated. The specific content of the environmental risk grade is:

[0071] S41: Taking each index in the environmental risk assessment index system as an evaluation factor, an evaluation index system set U={U1, U2, …, U n} is constructed; the environmental risk assessment result of the solid waste yard is divided into m grades, and the comment set V={V1, V2, …, V m} of the sampling fuzzy evaluation method is constructed, wherein n is the number of index in the evaluation index system set, and m is the number of comments in the comment set;

[0072] S42: According to the solid waste yard environmental risk assessment index classification and scoring standard formulated in S3, the membership degree of the single-factor evaluation index to the comment set V is calculated in combination with the trapezoidal membership function, and the corresponding fuzzy evaluation matrix R is obtained:

[0073]

[0074] In the formula, r ij is the membership degree of the ith element of the evaluation index system set U to the jth comment of the comment set V, i=1, 2, 3…n, and j=1, 2, 3…m;

[0075] S43: The fuzzy evaluation matrix R and the weight vector W are operated according to the fuzzy operator to obtain the solid waste yard environmental risk fuzzy evaluation set B:

[0076] W={w1, w2, …, w n}

[0077]

[0078] S44: The weighted average type fuzzy synthesis operator is adopted to calculate the actual score S of the risk evaluation:

[0079] S=BV T

[0080] The environmental risk grade is determined by comparing the solid waste yard environmental risk score.

[0081] In one specific embodiment, the following contents are included:

[0082] (I) Based on the natural environmental characteristics and influencing factors of solid waste storage yard, the environmental risk assessment index system is screened and established;

[0083] As shown in Figure 2 , the evaluation index system is based on the evaluation index system of "source-path-receptor" risk three elements, including two levels of index;

[0084] The first level index includes solid waste characteristics, yard characteristics, environmental characteristics; wherein,

[0085] The secondary indicators of solid waste characteristics include heavy metal Nemerow pollution index and acid-base;

[0086] The secondary indicators of yard characteristics include storage capacity, land area, service life, and anti-seepage form;

[0087] The secondary indicators of environmental characteristics include groundwater depth, annual rainfall, soil permeability of aeration zone, soil permeability of saturation zone, number of environmental sensitive points within 1km around the yard, population within 1km around the yard, distance from the yard to the nearest sensitive target, land use within 1km around the yard, and groundwater and surface water use within 1km around the yard.

[0088] (II) Determine the weight of each level index of the environmental risk assessment index system, and grade and quantify some non-quantitative indicators;

[0089] (1) For the convenience of data processing, some indicators that are difficult to quantify, such as anti-seepage form, land use, groundwater and surface water use, acid-base, soil permeability coefficient, etc. are graded and quantified according to five levels, and each level is scored. According to the grading and quantification of 0-10 points, the subsequent data processing is carried out with the quantified scores. As shown in Table 1.

[0090] Table 1 Index Evaluation Grade Score Results

[0091]

[0092] The heavy metal Nemerow pollution index is a comprehensive index of bulk industrial solid waste characteristics, which is characterized by Nemerow pollution index. The heavy metals copper, zinc, cadmium, lead, chromium, mercury, nickel, arsenic and inorganic fluoride in solid waste leaching toxicity are selected as the characterization parameters, and the calculation formula is as follows:

[0093]

[0094] P i =C i / S i

[0095] In the formula, P 综 is the comprehensive pollution index; P imaxIt is the maximum value of the single pollution index of heavy metal and fluoride pollutants. is the average pollution index of heavy metal and fluoride pollutants, C i is the leaching concentration of heavy metals and fluoride i, S i The maximum allowable emission limits for heavy metals and fluorides.

[0096] (2) The method for determining the indicator weight is: using the subjective and objective combined weighting method, that is, using the hierarchical analysis method to subjectively weight each indicator in the indicator system, and using the entropy weight method to objectively weight each indicator in the indicator system.

[0097] Among them, the hierarchical analysis method is a subjective weight calculation based on the 1 to 9 scale theory. Through the expert scoring results, the judgment matrix between each level is constructed.

[0098]

[0099] Where a ij =1, That is, the importance of factor I compared with factor j, and n is the number of weight indicators to be determined.

[0100] The above judgment matrix A is normalized using the following formula.

[0101]

[0102] The relative importance weight of the corresponding hierarchical indicators can be obtained. After the consistency test, the weight value of the criterion layer is multiplied by the weight value of the factor layer, and the subjective weight value of the indicator W1={w a1 ,w a2 ,…,w an}.

[0103] The entropy weight method is an objective weight calculation method. It summarizes the information of different types of bulk industrial solid waste dumps to form an original data matrix, and obtains the standard matrix X after standardization.

[0104]

[0105] Where n is the number of indicators in the evaluation index system, and k is the number of summarized cases of different types of bulk industrial solid waste landfills.

[0106] The original data matrix is ​​standardized and normalized, and the information entropy of each indicator is calculated.

[0107]

[0108] And calculate the information utility value, and normalize it to get the entropy weight of each indicator W2={w x1 ,w x2 ,…,wxn}。

[0109]

[0110] Under the premise of the minimum sum of deviation squares, 50% of the subjective weight and the objective entropy weight are added respectively as the final combined weight value:

[0111] W = (W1 + W2) / 2 = {w1, w2, ···, w n}。

[0112] For example, the calculated confirmed evaluation index weight value is:

[0113] W = {0.0811, 0.035, 0.0869, 0.0381, 0.0712, 0.2023, 0.045, 0.0242, 0.1056, 0.0474, 0.0536, 0.0659, 0.0591, 0.0509, 0.0337}.

[0114] (Three) Establish the grading and scoring standards of solid waste landfill environmental risk evaluation index;

[0115] According to the grading and scoring standards of solid waste landfill environmental risk evaluation index established in S3, the higher the score value obtained is, the greater the corresponding environmental risk is.

[0116] (Four) Based on the weight of each level index determined in S2, the environmental risk of solid waste landfill is evaluated by using the sampling fuzzy evaluation method, the risk evaluation score is calculated, and the environmental risk level is determined by comparing with the grading and scoring standards of environmental risk evaluation index established in S3.

[0117] (1) Taking each index in the environmental risk evaluation index system as the evaluation factor, the evaluation index system set U = {U1, U2, …, U n} is constructed; the environmental risk evaluation results of solid waste landfill are divided into m levels, and the evaluation set V = {V1, V2, …, V m} of the sampling fuzzy evaluation method is constructed, wherein n is the number of evaluation index system set indexes, and m is the number of evaluation in the evaluation set.

[0118] (2) According to the grading and scoring standards of solid waste landfill environmental risk evaluation index established in S3, the membership degree of single factor evaluation index to the evaluation set V is calculated by combining the trapezoidal membership function, and the corresponding fuzzy evaluation matrix R is obtained:

[0119]

[0120] In the formula, r ijTo evaluate the membership degree of the ith element of the index system set U belonging to the jth comment of the comment set V, i = 1, 2, 3...n, j = 1, 2, 3...m;

[0121] (3) The fuzzy evaluation matrix R and the weight vector W are operated according to the fuzzy operator to obtain the solid waste storage yard environmental risk fuzzy evaluation set B:

[0122] W = {w1, w2,..., wn} n}

[0123]

[0124] (4) The actual score S of risk evaluation is calculated by using the weighted average type fuzzy synthesis operator:

[0125] S = BV T

[0126] By comparing the environmental risk scores of solid waste storage yards, the environmental risk level is determined.

[0127] For example, taking 0-10 points as the score range, dividing into 5 risk levels, and taking the comment set range V = {2, 4, 6, 8, 10}, representing {low risk, low-medium risk, medium risk, high-medium risk, high risk}, the higher the score, the higher the environmental risk of the storage yard.

[0128] The trapezoidal membership function is used to construct the membership matrix of each evaluation level, and the larger the membership function value, the greater the possibility that the evaluation factor belongs to the risk level. Taking the above 5 levels as an example, the membership function is calculated as follows.

[0129]

[0130]

[0131]

[0132] In the formula, x is the measured value of the index, a, b, c, and d are the endpoint values and average values of the index evaluation standard intervals. For example, the heavy metal Nemerow pollution index is divided into 5 levels at 0.3, 0.6, 1.0, and 1.5; the seepage prevention form, land use mode, groundwater and surface water use, acid-base, soil permeability coefficient, etc. are divided by the quantitative score of 2, 4, 6, and 8; the storage capacity is divided by 10, 100, 500, and 1000 million m 3 ; the land area is divided by 1, 5, 10, and 50 million m 2; the service life is divided into 5, 10, 20 and 30 years; the groundwater depth is divided into 2, 4, 8 and 12 m; the annual rainfall is divided into 400, 600, 800 and 1200 mm; the number of environmental sensitive points within 1 km around the stockyard is divided into 2, 5, 8 and 10; the number of population within 1 km around the stockyard is divided into 50, 100, 1000 and 5000; the distance from the nearest sensitive target is divided into 100, 300, 500 and 1000 m; u i is the membership degree of the i-th element of the index set U belonging to the j-th evaluation in the evaluation set V, wherein i = 1, 2, 3...n, j = 1, 2, 3...m. In this embodiment, five risk levels are taken as an example, so m = 5.

[0133] The membership degrees of the single-factor evaluation index set to the evaluation set V are calculated by the above trapezoidal membership function, and the corresponding fuzzy evaluation matrix R is obtained.

[0134]

[0135] In the formula, r ij is the membership degree of the i-th element of the index set U belonging to the j-th evaluation in the evaluation set V, wherein i = 1, 2, 3...n, j = 1, 2, 3...m. In this embodiment, five risk levels are taken as an example, so m = 5.

[0136] The fuzzy evaluation set B is obtained by operating the single-factor evaluation matrix R and the weight vector W according to the fuzzy operator, and B is a fuzzy subset on the evaluation set V.

[0137]

[0138] In the formula, b1~b5 reflect the membership of the stockyard environmental risk level in the five-level evaluation, i.e., the membership degrees of low risk, low-medium risk, medium risk, high-medium risk and high risk, respectively.

[0139] Finally, the weighted average type fuzzy synthesis operator is used to calculate the comprehensive evaluation result S of the environmental risk of the large industrial solid waste stockyard, and the actual score is compared with the set evaluation set interval to obtain the corresponding environmental risk evaluation level.

[0140] S = BV T

[0141] For example, the calculation result S = 5.91, and according to the above 0~10 points as the five-level scoring range, the stockyard environmental risk level corresponds to medium risk, and is close to high-medium risk.

[0142] If the evaluation result is high environmental risk, certain risk control or engineering control measures should be considered for the solid waste stockyard, such as increasing vertical curtain and horizontal barrier, excavating and disposing part of the solid waste, and reducing the amount of the stockyard.

[0143] The various embodiments described in this specification are intended to be illustrative only and in no way limit the scope of the application. Changes and modifications can be made by those skilled in the art, which employ the principles of the application, without departing from the scope of the application. Accordingly, the application is not limited to the embodiments described herein, but instead has scope to encompass any choice whatsoever that is dependent on, or can be substituted in, the principal, new and inventive features that are described and claimed herein.

[0144] The above description of disclosed embodiments is intended to be illustrative only and not limiting of the application. Numerous modifications to these embodiments can be made by those skilled in the art without departing from the spirit or scope of the application. The scope of the application is not limited to the embodiments described herein, but rather extends to any that are dependent on, or can be substituted in, the principal, new and inventive features that are described and claimed herein.

Claims

1. A method for environmental risk assessment of bulk industrial solid waste dumps, characterized in that: The following steps are involved: S1: Based on the natural environmental characteristics and influencing factors of solid waste dumps, screen and establish an environmental risk assessment indicator system; S2: Determine the weights of indicators at each level of the environmental risk assessment indicator system, and quantify some non-quantitative indicators in a hierarchical manner; S3: Develop a classification and scoring standard for environmental risk assessment indicators for solid waste dumps; S4: Based on the weights of indicators at each level determined in S2, and in comparison with the environmental risk assessment indicator classification and scoring standards formulated in S3, the environmental risks of solid waste landfills are evaluated using the sampling fuzzy assessment method, the risk assessment score is calculated, and the environmental risk level is determined.

2. The method for environmental risk assessment of a bulk industrial solid waste dump according to claim 1, characterized in that: The environmental risk assessment indicator system screened and established in S1 includes two levels of indicators; The first-level indicators include solid waste characteristics, yard characteristics, and environmental characteristics; among them, Secondary indicators of solid waste characteristics include heavy metal Nemerow pollution index and acidity and alkalinity; Secondary indicators of storage yard characteristics include storage volume, floor area, service life, and anti-seepage type; Secondary indicators of environmental characteristics include groundwater depth, annual rainfall, soil permeability in the vadose zone, soil permeability in the saturated zone, number of environmentally sensitive points within 1 km of the storage yard, population within 1 km of the storage yard, distance between the storage yard and the nearest sensitive target, land use within 1 km of the storage yard, and groundwater and surface water usage within 1 km of the storage yard.

3. The method for environmental risk assessment of a bulk industrial solid waste dump according to claim 2, characterized in that: The heavy metal Nemerow pollution index is used for characterization. The characterization parameters are selected from the heavy metals copper, zinc, cadmium, lead, chromium, mercury, nickel, arsenic and inorganic fluoride in the leaching toxicity of solid waste. The calculation formula is as follows: P i =C i / S i Where, P 综 is the comprehensive pollution index; P imax It is the maximum value of the single pollution index of heavy metal and fluoride pollutants. is the average pollution index of heavy metal and fluoride pollutants, C i is the leaching concentration of heavy metals and fluoride i, S i The maximum allowable emission limits for heavy metals and fluorides.

4. The method for environmental risk assessment of a bulk industrial solid waste dump according to claim 1, characterized in that: In S2, the subjective and objective combined weighting method is used to determine the weights of indicators at each level of the environmental risk assessment indicator system; The analytic hierarchy process is used to subjectively weight each indicator in the environmental risk assessment index system, and the entropy weight method is used to objectively weight each indicator in the environmental risk assessment index system. Based on the minimum sum of squares of deviations, 50% of the sum of subjective weights and objective entropy weights are taken as the final combined weight value.

5. The method for environmental risk assessment of a bulk industrial solid waste dump according to claim 1, characterized in that: Some non-quantitative indicators in S2 include anti-seepage form, land use mode, groundwater and surface water use, acidity and alkalinity, and soil permeability coefficient; among them, The anti-seepage measures were graded and quantified according to five levels: no anti-seepage measures, simple soil covering and greening, partial or no anti-seepage measures on the bottom / top surface of the storage yard, only anti-seepage measures on the bottom / top surface of the storage yard, and complete anti-seepage facilities. The quantified scores were used for subsequent data processing. Land use patterns are quantified according to five levels: unused land, mining land, industrial land, residential and office land, agricultural land, and protected areas. The quantified scores are used for subsequent data processing. Groundwater and surface water uses are quantified according to five levels: non-use, industrial use, agricultural irrigation water, recharge water source, domestic water and protected area. The quantified scores are used for subsequent data processing. Acidity and alkalinity were graded and quantified according to five levels of pH: 6-9, 4.5-6 and 9-10, 3-4.5 and 10-11, 2-3 and 11-12.5, 0-2 and 12.5-14, and the quantified scores were used for subsequent data processing; Soil permeability is based on a permeability coefficient value >10 -1 cm / s, 10 -1 ~10 -3 cm / s, 10 -3 ~10 -5 cm / s, 10 -5 ~10 -7 cm / s, <10 -7 The five levels of cm / s are graded and quantified, and the subsequent data processing is carried out based on the quantified scores.

6. The method for environmental risk assessment of a bulk industrial solid waste dump according to claim 1, characterized in that: Scoring is performed according to the solid waste landfill environmental risk assessment index classification and scoring standards formulated in S3. The higher the score obtained, the greater the corresponding environmental risk.

7. The method for environmental risk assessment of a bulk industrial solid waste dump according to claim 1, characterized in that: In S4, the sampling fuzzy evaluation method is used to evaluate the environmental risk of the solid waste dump site, and the risk assessment score is calculated. The specific content of determining the environmental risk level is as follows: S41: Taking the indicators in the environmental risk assessment indicator system as evaluation factors, an evaluation indicator system set U = {U1, U2, ..., U n }; Divide the environmental risk assessment results of solid waste dumps into m levels, and construct the evaluation set of sampling fuzzy evaluation method as V = {V1, V2, ..., V m }, where n is the number of indicators in the evaluation index system set, and m is the number of comments in the comment set; S42: Based on the solid waste dump environmental risk assessment index classification and scoring standards formulated in S3, combined with the trapezoidal membership function, the membership degree of the single factor evaluation index to the comment set V is calculated, and the corresponding fuzzy evaluation matrix R is obtained: Where r ij is the membership degree of the i-th element of the evaluation index system set U to the j-th comment in the comment set V, i = 1, 2, 3...n, j = 1, 2, 3...m; S43: The fuzzy evaluation matrix R and the weight vector W are operated according to the fuzzy operator to obtain the fuzzy evaluation set B of the solid waste dump environmental risk: W={w1,w2,···,w n } S44: Use the weighted average fuzzy synthesis operator to calculate the actual score S of the risk assessment: S=BV T Determine the environmental risk level by comparing the environmental risk scores of solid waste dumps.

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