Figures (14)  Tables (8)
    • Figure 1. 

      Process of analyzing chemical production accidents based on data mining.

    • Figure 2. 

      Example of a vertical database.

    • Figure 3. 

      Histogram of the top 20 frequency ranked items.

    • Figure 4. 

      Examples of different association rule types.

    • Figure 5. 

      Visualization of valid association rules.

    • Figure 6. 

      Scatter plot of the distribution of important values of association rules.

    • Figure 7. 

      Network modeling of accident causative factors.

    • Figure 8. 

      Distribution of each centrality value of nodes. (a) Betweenness-degree centrality distribution, (b) Closeness-degree centrality distribution, and (c) Eigenvector-degree centrality distribution.

    • Figure 9. 

      Trend of Accident-Percentage from 2012 to 2023.

    • Figure 10. 

      The trend of the time series data after first-order differencing.

    • Figure 11. 

      (a) Auto correlation functions plot. (b) Partial auto correlation functions plot.

    • Figure 12. 

      Correlation plot for model feasibility validation. (a) Standardized residual. (b) ACF of residual. (c) p-value for Ljung-Box Statistic.

    • Figure 13. 

      Trend predition with historical Accident-Percentage data.

    • Figure 14. 

      Comparison of the model predicition values with the actual values in the year 2023.

    • CategoryInformation extraction content
      Basic informationTimes: years, months, season, time period.
      Corporations: nature of enterprise, industry, province.
      Addressees involved: operational phase, fixtures, type of hazardous chemical.
      Cause informationAccident patterns: first accident, secondary accident.
      Causative factor layer: man, machine, environment, management.
      Consequence informationAccident casualties: number of deaths, number of injuries.
      Classification of severity: fatal, injury, harmless.

      Table 1. 

      Category of accident information extraction.

    • LayersCausative factors
      HumanImproper or faulty operation (H01)Illegal changes in production processes or procedures (H10)
      Unauthorized welding operation (H02)Smoking violation (H11)
      Work without safety equipment (H03)Human-caused fires (H12)
      Violation of safety operating regulations (H04)Human-caused damage to equipment or piping (H13)
      Unauthorized use of equipment or raw materials that pose a safety hazard (H05)Failure to close valves promptly after operation (H14)
      Failure to carry out fire separation or clearance of flammable material prior to operation (H06)Unauthorized absence (H15)
      Incorrect or excessive addition of reaction materials (H07)Command error (H16)
      Failure to conduct safety tests prior to operating in a limited space (H08)Lack of specialized skills (H17)
      Operating equipment without appropriate qualifications (H09)
      MachineEquipment or system failure (Eq01)Equipment ageing leakage (Eq13)
      Circuit short or power supply system failure (Eq02)Equipment not equipped with electrostatic discharge device (Eq14)
      Pipe rupture (Eq03)Valve failure (Eq15)
      Problems with process or technology (Eq04)Heat or static electricity from mechanical friction (Eq16)
      Reaction kettle over-temperature or over-
      pressure (Eq05)
      Material strength defects (Eq17)
      Tank rupture leak (Eq06)Clogged pipes (Eq18)
      Seal failure or ineffective sealing (Eq07)Failure of ventilation equipment (Eq19)
      Valve internal leakage (Eq08)Pump body failure (Eq20)
      Broken or disconnected pipe connections (Eq09)Boiler rupture (Eq21)
      Safety defects in equipment or failure of safety interlocking devices (Eq10)Flange leakage (Eq22)
      Loose or dislodged valve (Eq11)Collapse of support frame (Eq23)
      Seal dislodged or corroded (Eq12)Safety valve trip (Eq24)
      EnvironmentHigh temperature exposure (En01)Ambient moisture corrodes equipment or reacts with substances (En04)
      Rainstorm (En02)Lightning fire (En05)
      Gale (En03)Cold temperatures (En06)
      ManagementFailure to rationalize storage according to the nature of the chemical (M01)Illegal handling of reaction gases or wastes (M05)
      Illegal business (M02)Failure to regularly service equipment (M06)
      Ventilation not switched on due to chaotic management (M03)Deficiencies in fire management (M07)
      Deficiencies in security management (M04)Insufficient training in emergency response capacity (M08)
      First
      Accident
      Explosion (FA01)Over-pressure (FA06)
      Fire (FA02)Object strikes (FA07)
      Poisoning (FA03)Fall from height (FA08)
      Leakage (FA04)Other (FA09)
      Over-temperature (FA05)
      Secondary AccidentExplosion (SA01)Leakage (SA05)
      Fire (SA02)Object strikes (SA06)
      Poisoning (SA03)Fall from height (SA07)
      Blindly Rescue (SA04)No secondary accidents (SA08)

      Table 2. 

      Causative factors and patterns of chemical production accidents.

    • AlgorithmsNo. of rules generatedNo. of valid
      rules (lift > 1)
      Time
      (t/s)
      Apriori1674987
      Eclat966362

      Table 3. 

      Comparison of two algorithms.

    • LhsRhsSupportConfidenceLiftCount
      1{Eq05}=>{FA06, SA01}0.0188570.87260910.59438639
      2{H03, M08}=>{FA03}0.0308570.72060210.44545245
      3{Eq04}=>{FA06, SA01}0.0268570.7527789.13058735
      4{Eq03, Eq17}=>{FA04, SA03}0.0182860.6836368.46290541
      5{H02, H04}=>{FA02}0.0222860.4698817.87309634
      6{Eq06, Eq17}=>{SA03}0.0212380.7124577.56713225
      7{H14, M08}=>{SA04}0.0154290.6751167.46746318
      8{H03}=>{FA01, SA07}0.0354290.7469886.90324921
      9{H06}=>{FA02, SA08}0.0165710.6304356.51312329
      10{H01, Eq05}=>{FA01, SA01}0.0165710.6277055.94757125
      11{Eq16, Eq14}=>{FA01}0.0182860.7714295.81159426
      12{En04, M01}=>{FA01}0.0280010.6805565.29909231
      13{H09, H16}=>{FA01, SA02}0.0155710.7583334.94680422
      14{M02, M05}=>{FA03}0.0178570.4418614.85799919
      15{M06}=>{FA04, SA02}0.0394290.5348844.73986322
      16{En01, M01}=>{FA02, SA01}0.0542230.7521214.56242324
      17{H02, M07}=>{FA02, SA08}0.0175710.7857144.23211818
      18{H15, Eq05}=>{FA06}0.0354520.5722544.22519331
      19{Eq18, M06}=>{FA04}0.0254610.7122524.19575219
      20{Eq13, Eq17}=>{FA04, SA03}0.0234290.4171013.94189841
      21{Eq08, Eq17}=>{FA04, SA02}0.0154290.8709683.83307421
      22{Eq05, Eq04}=>{FA01, SA06}0.0162860.2142863.74683518
      23{H08}=>{FA03, SA04}0.0175710.7116283.72200934
      24{Eq05, H07}=>{FA05, SA01}0.0154290.7761913.50966218
      25{Eq01, Eq24}=>{FA04, SA03}0.0135710.2365593.44675522
      26{M08}=>{SA04}0.0345690.7542033.43461219
      27{H11}=>{FA02}0.0162860.8571433.41685614
      28{En04, En02}=>{SA01}0.0178570.6795703.38749314
      29{H01, H17}=>{FA01, SA03}0.0228570.4378693.31901325
      30{H12, M07}=>{FA02}0.0191430.8214293.27448721
      31{M01, M03}=>{FA01}0.0242860.7681823.26496216
      32{H01}=>{FA04, SA03}0.0251430.5606563.17313731
      33{Eq19, H08}=>{FA01, SA01}0.0212380.7926623.15774515
      34{Eq06}=>{FA04, SA03}0.0114290.5263163.11736220
      35{Eq12, Eq10}=>{FA04, SA03}0.0108570.7521133.09014919
      36{Eq23}=>{FA08}0.0341370.7632243.01527612
      37{Eq09, Eq17}=>{FA04, SA01}0.0154290.6542252.92750923
      38{Eq02}=>{FA02, SA03}0.0228570.6636362.86290532
      39{H04, H17}=>{FA07}0.0114290.5150542.85109220
      40{Eq07, Eq22}=>{FA04}0.0154290.7437542.74454019
      41{Eq03, Eq20}=>{FA06, SA05}0.0137140.6522842.60223017
      42{Eq11, H13}=>{SA03}0.0246430.4269922.54113824
      43{Eq15, Eq10}=>{FA04, SA01}0.0358240.7242712.42121412
      44{M03, H08}=>{FA01, SA02}0.0423410.5519812.34872217
      45{M01, M02}=>{FA02, SA01}0.0114290.3985072.26793231
      46{H01, H16}=>{FA01}0.0205710.4150822.25338226
      47{Eq04, Eq16}=>{SA01}0.0165710.6178572.19963619
      48{Eq17, Eq05}=>{FA01, SA03}0.0102860.3812552.13146627
      49{Eq03, H10}=>{SA02}0.0177140.3522732.11680721
      50{H13, Eq17}=>{FA04, SA03}0.0102860.4864861.95713018
      51{Eq10, Eq05}=>{FA04, SA02}0.0177140.3246381.95416531
      52{H05, M04}=>{FA02, SA03}0.0182860.5324321.83678821
      53{En03, H03}=>{FA08}0.0125710.5265591.76947715
      54{M01}=>{SA03}0.0137140.3582091.73647118
      55{H06}=>{SA01}0.0120010.5384621.70707914
      56{H05}=>{FA01}0.0137140.3750001.59284124
      57{H01}=>{FA06, SA01}0.0114290.7851161.47455320
      58{Eq21, Eq17}=>{FA04}0.0242750.4124141.26513414
      59{Eq22, En06}=>{SA03}0.0242540.7031451.25213210
      60{M04}=>{SA02}0.0165710.3918921.24241113
      61{M04}=>{SA03}0.0114290.2302701.08729420
      62{En05}=>{FA02}0.0293120.7861161.0024317
      63{En03, Eq23}=>{FA08}0.0274160.5324411.00012310

      Table 4. 

      Table of results of association rules for chemical production accidents.

    • Evaluation indicatorsCausative factor nodes of chemical production accidentValue
      Degree distributionMaterial strength defects (Eq17)21
      Reaction kettle over-temperature or over-pressure (Eq05)16
      Improper or faulty operation (H01): 1313
      Failure to rationalize storage according to the nature of the chemical (M01)13
      Equipment or system failure (Eq01)11
      Problems with process or technology (Eq04)7
      Safety defects in equipment or failure of safety interlocking devices (Eq10)5
      Failure to conduct safety tests prior to operating in a limited space (H08)5
      Betweenness centralityReaction kettle over-temperature or over-pressure (Eq05)53.159
      Material strength defects (Eq17)36.806
      Problems with process or technology (Eq04)33.199
      Failure to rationalize storage according to the nature of the chemical (M01)28.638
      Safety defects in equipment or failure of safety interlocking devices (Eq10)9.658
      Illegal changes in production processes or procedures (H10)9.542
      Illegal business (M02)8.993
      Insufficient training in emergency response capacity (M08)8.861
      Closeness centralityImproper or faulty operation (H01)1.0
      Material strength defects (Eq17)1.0
      Deficiencies in security management (M04)0.714286
      Illegal changes in production processes or procedures (H10)0.707421
      Reaction kettle over-temperature or over-pressure (Eq05)0.666667
      Work without safety equipment (H03)0.588235
      Lack of specialized skills (H17)0.583333
      Failure to rationalize storage according to the nature of the chemical (M01)0.574492
      Eigenvector centralityFailure to conduct safety tests prior to operating in a limited space (H08)0.482147
      Illegal business (M02)0.422739
      Failure to rationalize storage according to the nature of the chemical (M01)0.415532
      Incorrect or excessive addition of reaction materials (H07)0.402775
      Reaction kettle over-temperature or over-pressure (Eq05)0.384915
      Insufficient training in emergency response capacity (M08)0.372148
      Ambient moisture corrodes equipment or reacts with substances (En04)0.344168
      Failure to regularly service equipment (M06)0.328852

      Table 5. 

      Key causative factors of chemical production accidents.

    • DataDickey-FullerLag orderp-valueAlternative
      Original series ADF testDa1−3.447350.06219Stationary
      ADF test after first-order differencingDa2−6.236450.01Stationary

      Table 6. 

      ADF test results.

    • SARIMAX modelModel evaluation criterion
      AICSigma2SBICLog likelihood
      SARIMA(1,1,2) (1,1,0)[4]-AR(X)−149.877.96−144.0276.03
      SARIMA(1,1,1)(1,1,0)[4]-AR(X)−151.828.57−144.3177.31
      SARIMA(0,1,1)(1,1,0)[4]-AR(X)−153.538.89−146.8880.77
      SARIMA(0,1,2)(1,1,0)[4]-AR(X)−151.798.44−145.9780.93
      SARIMA(2,1,2)(1,1,0)[4]-AR(X)−147.987.24−143.7375.92
      SARIMA(2,1,0)(1,1,0)[4]-AR(X)−146.397.03−144.6875.41
      SARIMA(2,1,1)(1,1,0)[4]-AR(X)−149.957.91−144.2776.58
      SARIMA(1,1,0)(1,1,0)[4]-AR(X)−147.747.54−145.5376.21

      Table 7. 

      Values of different evaluation indicators for the SARIMA models.

    • ForecastLo80Hi80Lo95Hi95
      2023 Q10.17204330.13335290.21073370.11287140.2312152
      2023 Q20.20651480.16782440.24520530.14734290.2656867
      2023 Q30.37372030.33502990.41241070.31454840.4328922
      2023 Q40.24998290.21129250.28867350.19081120.3091548

      Table 8. 

      SARIMAX predition values for the year 2023.