Emission Control of Asphalt Mixing Plant

Abstract

According to an embodiment of the first aspect of the present invention, an asphalt mixing plant is provided, which includes a plurality of devices and an emission measurement unit configured to measure the current emissions of the asphalt mixing plant and provide a current emission value. The asphalt mixing plant further includes a plurality of process sensors configured to sense the process parameters of the devices of the asphalt mixing plant. Additionally, a control unit including an emission prediction unit is provided. The control unit is configured to receive and process the current emission value from the emission measurement unit, and receive and process the process parameters from the plurality of process sensors. The control unit is further configured to calculate, by the emission prediction unit, a prediction of the average emission value of one or more target substances within a predefined target time interval, and if, according to the prediction of the emission prediction unit, it is expected to exceed a predefined threshold of the average emission value within the predefined target interval, then perform an alarm process. The alarm process includes a plurality of actions for reducing emissions.

Description

Technical Field

[0001] The present invention generally relates to an asphalt mixing plant including a control unit. On the other hand, it relates to a method for operating an asphalt mixing plant and a computer program product for operating a control unit of an asphalt mixing plant. Background Art

[0002] In an asphalt mixing plant, the asphalt mixture is produced by thermal mixing of mineral rock, filler, bitumen, and possibly additives. The production of the asphalt mixture is a complex process usually controlled by a central control unit.

[0003] There are generally two main production methods.

[0004] According to the continuous production method, the mixing process is carried out in a continuous manner. More particularly, the individual components of the asphalt mixture are continuously added to the mixing process. Under the same asphalt mixing recipe, this method is particularly suitable for large volumes.

[0005] According to the discontinuous production method, the pre-weighed components of the bitumen mixture are batch-mixed in an asphalt mixer. This method is more flexible because it allows the asphalt mixing recipe to be changed batch by batch. In addition, a higher mixing quality is achieved and subsequently a higher quality asphalt mixture is achieved.

[0006] The increased awareness and sensitivity towards industrial emissions and the corresponding regulatory framework have led to an increasing demand for the monitoring, measurement, and reduction of emissions from such asphalt mixing plants. Such regulations include, for example, the German air pollution control regulation titled "Technische Anleitung zur Reinhaltung der Luft" and commonly known as "TALuft".

[0007] Due to the complexity of the asphalt production process, it is difficult to predict emissions in a reliable manner based on the operating parameters of the plant.

[0008] Furthermore, end-of-pipe solutions such as adsorption filters may reduce the production capacity of the plant and require additional investment costs, which results in higher production costs. Summary of the Invention

[0009] A problem of one aspect of the present invention is to provide an asphalt mixing plant that allows emissions to be controlled and / or reduced in an efficient and reliable manner.

[0010] In particular, aspects of the present invention address the problem of providing an asphalt mixing plant that, on the one hand, allows compliance with relevant emission regulations, but on the other hand still promotes efficient production while having limited restrictions on production capacity.

[0011] According to an embodiment of a first aspect of the present invention, there is provided an asphalt mixing plant comprising a plurality of devices and an emission measurement unit configured to measure the current emissions of the mixing plant and provide a current emission value. The asphalt mixing plant further comprises a plurality of process sensors configured to sense process parameters of the devices of the asphalt mixing plant. Additionally, a control unit comprising an emission prediction unit is provided. The control unit is configured to receive and process the current emission value from the emission measurement unit, and to receive and process the process parameters from the plurality of process sensors. The control unit is further configured to calculate, by means of the emission prediction unit, a prediction of the average emission value of one or more target substances within a predefined target time interval, and to execute one or more alarm procedures if, according to the prediction of the emission prediction unit, it is expected to exceed a predefined threshold of the average emission value within the predefined target interval or to exceed a plurality of predefined thresholds. The one or more alarm procedures include a plurality of actions for reducing emissions.

[0012] Such an implemented asphalt mixing plant allows the asphalt mixing plant to be operated in such a way that it does not exceed the average emission value within a predefined target interval and the asphalt mixing plant complies with the regulatory requirements specifying the maximum average emission value within that target interval.

[0013] Thus, the asphalt mixing plant according to an embodiment of the present invention focuses on the control of the average emission value rather than the control of instantaneous peaks. This provides the advantage that individual emission peaks can be eliminated and the devices of the plant can be operated in an effective but still environmentally acceptable manner. Additionally, with such a configuration of the control unit, sudden changes in the operating conditions and control parameters of the various devices can be avoided, which in turn can reduce, for example, energy consumption and wear and can increase the lifespan of the devices.

[0014] According to some embodiments, the emission measurement unit may be a unit certified and calibrated by an official agency and provided in particular for monitoring the emissions of the plant for compliance with the corresponding emission regulations. According to such an embodiment, the certified emission measurement unit has an interface that also provides the measurement values externally and is then used by the control unit and its emission prediction unit. Such a certified emission measurement unit may also be referred to as a continuous emission monitoring system (CEMS).

[0015] The control unit according to an embodiment of the present invention includes an emission prediction unit that receives and processes measured emission values from an emission measurement unit and calculates a prediction of the average emission value within a current target time interval based on these measured emission values. If it is predicted that the calculated prediction will exceed a corresponding threshold, the control unit performs one or more alarm processes. Such alarm processes may include a plurality of actions aimed at reducing emissions in order to comply with the corresponding threshold.

[0016] To adopt an optimal action plan, a plurality of processing sensors provide the control unit with an overview of the operating states of various devices of the station, in particular the devices or operating parameters that are the main causes of emissions, such as material temperature or hot gas temperature. Then, the control unit can decide what measures should be taken to reduce emissions within the corresponding target interval based on various operating parameters.

[0017] Such a scheme using predictions within a target interval based on actual emission measurements is particularly applicable to asphalt mixing plants because it is more uncertain to model the emissions of asphalt mixing plants only based on operating parameters than using the method of the present invention. More particularly, in many cases, such modeling is simply impossible because of the property changes of some processed materials (e.g., recycled asphalt (RA)).

[0018] According to some embodiments, the target interval may be an interval of 30 minutes or an interval of 1 day, in particular, 1 calendar day. These are typical values used by official agencies to specify the maximum average emissions. Such values are specified, for example, in German "TA Luft".

[0019] According to a preferred embodiment, the control unit may be configured to regularly calculate in parallel one or more predictions of the average emission value within a first target time interval and one or more predictions of the average emission value within a second target time interval. The first target time interval and the second target time interval have different lengths. According to an embodiment, the second target time interval is longer than the first target time interval. According to an embodiment, the first target time interval may be an interval of 30 minutes and the second target time interval may be an interval of 1 calendar day.

[0020] Such parallel observation and control of two different target time intervals can be used to control short-term and long-term target time intervals in parallel and use the devices of the station in an efficient but still environmentally acceptable manner.

[0021] According to a preferred embodiment, the alarm process is a staggered alarm process. The staggered alarm process includes at least a first stage and a second stage. The control unit is configured to perform a first set of actions for reducing emissions in the first stage and a second set of actions for reducing emissions in the second stage.

[0022] Preferably, the staggered alert process includes a third stage as another stage. Then, the control unit is configured to perform a third set of actions for reducing emissions in the third stage.

[0023] According to another embodiment, the staggered alert process includes a fourth stage. Then, the control unit is configured to perform a fourth set of actions for reducing emissions in the fourth stage.

[0024] Such a staggered alert process with subsequent stages allows for flexible and efficient control of the actions for reducing emissions. In particular, according to another embodiment, it allows less disruptive actions to be assigned to the previous stages. More particularly, according to an embodiment, the first set of actions may include actions that are less disruptive to the continuous operation of the asphalt mixing plant than the actions in the second set of actions. Additionally, for an embodiment having a third stage, the second set of actions may include actions that are less disruptive to the continuous operation of the asphalt mixing plant than the actions in the third set of actions.

[0025] Furthermore, for an embodiment having a fourth stage, the third set of actions may include actions that are less disruptive to the continuous operation of the asphalt mixing plant than the actions in the fourth set of actions.

[0026] Actions that are less disruptive may particularly be small modifications that allow the asphalt production to continue with only a relatively small or moderate impact on production efficiency, production throughput, and / or production capacity.

[0027] According to some embodiments, the first set of actions, the second set of actions, the third set of actions, and / or the fourth set of actions include sending an alert message to the operator of the asphalt mixing plant. Such an alert message may be, for example, a warning that a corresponding threshold is expected to be exceeded and that action needs to be taken or will be taken manually by the operator or automatically by the control unit and its emissions prediction unit.

[0028] According to an embodiment, the first set of actions and / or the second set of actions include sending one or more action suggestions to the operator of the asphalt mixing plant. The control unit is configured to send action suggestions based on the current operating parameters of the asphalt mixing plant.

[0029] Sending such action suggestions provides the operator with some flexibility and discretion to decide on the most appropriate actions. Additionally, such action suggestions may include actions that the control unit may not be able to perform automatically.

[0030] According to an embodiment, the first set of actions and / or the second set of actions include automatically changing the operating parameters of one or more of the plurality of devices of the asphalt mixing plant by the control unit.

[0031] Preferably, the automatically executed actions are actions that do not require operator discretion. In particular, such actions may include actions that must be executed to avoid exceeding a threshold and that require immediate action without further delay.

[0032] According to an embodiment, the third set of actions includes automatically initiating end actions and / or active treatment steps by the control unit as supplementary measures for reducing emissions.

[0033] An end action may be defined as an action that does not change the production process itself but uses downstream measures to reduce emissions.

[0034] An active treatment step may be defined as an active step taken in the production process to reduce emissions.

[0035] The end actions and / or active treatment steps may include changing the associated operating parameters of the asphalt mixing plant.

[0036] Such end actions and active treatment steps can only be taken if the corresponding technology has been installed on the plant. End actions may include, for example, adsorption filters or exhaust gas scrubbing. Active treatment steps include, for example, lime injection or urea injection. Since end actions and active treatment steps generally reduce the efficiency and / or capacity of production, according to a preferred embodiment, they are only activated in the third stage of the staggered alarm process to avoid unnecessary activation.

[0037] According to an embodiment, the third set of actions (in the case of a total of three sets of actions) or the fourth set of actions (in the case of a total of four sets of actions) includes stopping the feeding and dosing of recycled asphalt to the asphalt mixing plant and / or the asphalt mixture.

[0038] Since recycled asphalt is a major emission source (especially VOC emissions), this measure is very efficient in reducing emissions. However, this may significantly increase production costs. Therefore, since this measure is only used as a last resort, the asphalt mixing plant according to an embodiment of the present invention provides on the one hand a favorable overall efficiency and a favorable balance between production efficiency and production capacity, and on the other hand complies with emission regulations.

[0039] According to an embodiment, the staggered alarm process includes starting a timer after entering the first stage, and when the timer expires, evaluating whether the predefined threshold will still be exceeded according to the current prediction of the emission prediction unit. If the predefined threshold of the average emission value will still be exceeded according to the latest prediction of the emission prediction unit, then the control unit will automatically enter the second stage. On the other hand, if the predefined threshold is no longer exceeded according to the latest prediction of the emission prediction unit, then the control unit will terminate the actions of the first stage and / or indicate to the operator that the action can be terminated.

[0040] If the actions in the first stage are insufficient, then this automatic entry into the second stage ensures that there is no further delay in taking actions.

[0041] According to an embodiment, the staggered alarm process includes starting a timer after entering the second stage, and when the timer expires, evaluating whether the predefined threshold will still be exceeded based on the latest prediction of the emission prediction unit. If the predefined threshold of the average emission value will still be exceeded according to the latest prediction of the emission prediction unit, then the control unit will automatically enter the third stage. Conversely, if the predefined threshold is no longer exceeded according to the latest prediction of the emission prediction unit, then the control unit will terminate the actions of the first and second stages and / or indicate to the operator that the action has been or can be terminated.

[0042] If the actions in the second stage are insufficient, then this automatic entry into the third stage ensures that there is no further delay in taking actions.

[0043] According to an embodiment, the control unit includes a memory. The memory is configured to store a look-up table, and the look-up table includes an action matrix. This is an efficient and reliable method for implementing decision logic in the control unit. The action matrix may include actions to be taken according to the stage, operating parameters of the station, target substance(s), and / or the corresponding configuration of the station.

[0044] According to an embodiment, the emission prediction unit is configured to calculate a linear prediction by linear extrapolation of measured emission values (in particular, the measured intermediate average emission values of sub-intervals of the target interval) based on a first prediction method, and to calculate the measured intermediate average emission value of the latest sub-interval of the target interval by a second prediction method.

[0045] According to an embodiment, the emission prediction unit is further configured to calculate the measured current average emission value of the previous sub-interval of the target interval by a third prediction method.

[0046] Using such different prediction methods, different sensitivities and responsiveness to emission changes can be achieved. While the linear prediction usually reacts quite quickly to emission changes, the average emission value of a single sub-interval or all previous sub-intervals of the corresponding target interval usually reacts more slowly.

[0047] According to a preferred embodiment, the control unit is configured to: enter the first stage if it is predicted to exceed the threshold according to the first prediction method.

[0048] According to a preferred embodiment, the control unit is configured to: enter the second stage if it is predicted to exceed the threshold according to the second prediction method and / or the third prediction method.

[0049] According to a preferred embodiment, the control unit is configured to: enter the third stage if it is predicted, according to the second prediction method and / or the third prediction method, to exceed a threshold value.

[0050] Such an embodiment has the following advantages: the first stage is activated quite quickly, while for the second and third stages, before entering, some kind of confirmation of the first (fast) prediction method needs to be carried out through the second and / or third (slow) prediction methods.

[0051] According to an embodiment, the control unit is configured to: if it is predicted that the threshold value becomes lower than the threshold values according to the first prediction method and according to the second prediction method, then turn off any actions of the alarm process, in particular the first, second, and / or third sets of actions.

[0052] According to an embodiment, the control unit is configured to: if it is predicted that the threshold value becomes lower than the threshold values according to the first prediction method and according to the third prediction method, then turn off any actions of the alarm process.

[0053] According to an embodiment, the control unit is configured to: if it is predicted that the threshold value becomes lower than the threshold values according to the first prediction method, the second prediction method, and the third prediction method, then turn off any actions of the alarm process.

[0054] Such an embodiment can ensure that the actions are turned off only when they are indeed no longer needed.

[0055] According to an embodiment, the first set of actions may include reducing the feed rate of the recycled asphalt, increasing the feed rate of the virgin aggregate, checking the settings of the burners of the asphalt mixing plant, reducing the material temperature of the hot recycled asphalt (especially the outlet material temperature), reducing the material temperature of the asphalt mixture in the mixer of the plant, and / or reducing the content of the recycled asphalt in the asphalt mixture material.

[0056] It has been found that these actions are particularly efficient for reducing emissions.

[0057] According to an embodiment, the second set of actions may include preventing (especially automatically preventing) an increase in the burner load of the burners of the asphalt mixing plant (especially the burner of the virgin aggregate silo and / or the burner of the recycled asphalt silo). The second set of actions may also include reducing the temperature of the hot recycled asphalt to an adjustable target temperature or adjusting the burner load according to the adjustable target temperature of the hot recycled asphalt, especially the burner load of the burner of the virgin aggregate silo and / or the burner load of the burner of the recycled asphalt silo. The second set of actions may also include reducing the feed rate of the recycled asphalt to the recycled asphalt silo by a predefined percentage and / or reducing the dosing rate of the cold and / or hot recycled asphalt by a predefined percentage.

[0058] It has been found that these actions are particularly efficient for reducing emissions.

[0059] According to an embodiment of another aspect of the present invention, a method for operating an asphalt mixing plant is provided. The asphalt mixing plant includes a plurality of devices, an emission measurement unit, a plurality of process sensors, and a control unit including an emission prediction unit. The method includes the following steps: measuring the current emissions of the asphalt mixing plant by the emission measurement unit, and providing the current emission value to the control unit by the emission measurement unit. Further steps include sensing the process parameters of the devices of the asphalt mixing plant by the process sensors. Further steps include: receiving the current emission value by the control unit from the emission measurement unit, receiving the process parameters by the control unit from the plurality of process sensors, and calculating, by the emission prediction unit, a prediction of the average emission value of one or more target substances within a predefined target time interval. Further steps include: if, according to the prediction of the emission prediction unit, it is expected to exceed a predefined threshold of the average emission value within the predefined target interval, then performing an alarm process by the control unit.

[0060] According to an embodiment of another aspect of the present invention, a computer program product for operating a control unit of an asphalt mixing plant is provided. The control unit includes an emission prediction unit. The asphalt mixing plant includes a plurality of devices, an emission measurement unit configured to measure the current emissions of the asphalt mixing plant, and a plurality of process sensors. The computer program product includes a computer-readable storage medium having program instructions implemented therewith. The program instructions are executable by the control unit to cause the control unit to perform a method that includes: receiving the current emission value by the control unit from the emission measurement unit, and receiving the process parameters by the control unit from the plurality of process sensors. Further steps include calculating, by the emission prediction unit, a prediction of the average emission value of one or more target substances within a predefined target time interval, and if, according to the prediction of the emission prediction unit, it is expected to exceed a predefined threshold of the average emission value within the predefined target interval, then performing an alarm process by the control unit.

[0061] The features and advantages of one aspect of the present invention can be appropriately applied to other aspects of the present invention.

[0062] Other advantageous embodiments are listed in the dependent claims and in the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] The present invention will be better understood from the following detailed description, and other objects than those described above will become apparent. The description refers to the accompanying drawings, in which:

[0064] Figure 1 A schematic block diagram of an asphalt mixing plant according to an embodiment of the present invention is shown;

[0065] Figure 2 A schematic block diagram of the emission measurement unit is shown;

[0066] Figure 3 A flowchart showing a method for operating an asphalt mixing plant;

[0067] Figure 4 A flowchart showing a method for operating an asphalt mixing plant;

[0068] Figure 5 A diagram showing a calculation example of the prediction of the average emission value performed by the emission prediction unit;

[0069] Figure 6 A diagram showing another calculation example of the prediction of the average emission value performed by the emission prediction unit;

[0070] Figure 7 A flowchart showing an asphalt mixing process and associated equipment of an asphalt mixing plant; and

[0071] Figure 8 A diagram showing an action matrix according to an embodiment of the present invention. Detailed Description

[0072] In the following description, the following abbreviations may be used:

[0073] AT Active Treatment Unit;

[0074] CE Control Element;

[0075] CS Control Signal;

[0076] DAV Daily Average Value or Daily Mean Value;

[0077] EM Emission Measurement Unit;

[0078] EP Emission Prediction Unit;

[0079] EOP End

[0080] EV Emission Value;

[0081] HAV Half-Hour Average Value or Half-Hour Mean Value;

[0082] Mem. Memory;

[0083] PP Processing Parameter;

[0084] Proc. Processor;

[0085] RA Recycled Asphalt;

[0086] RAC Cold Recycled Asphalt;

[0087] RAH Hot Recycled Asphalt;

[0088] RAP Recycled asphalt pavement;

[0089] S Processing sensor;

[0090] VA Virgin aggregate; and

[0091] VOC-C1 Volatile organic compounds, counted by carbon atoms;

[0092] Using RAP can reduce production costs and avoid asphalt waste.

[0093] Recycled asphalt can be added to the asphalt mixing process via a separate drum (e.g., a parallel drum or a ringed drum).

[0094] Recycled asphalt can also be directly added to the mixer and / or the hot elevator of an asphalt mixing plant.

[0095] Figure 1 Fig. shows a schematic block diagram of an asphalt mixing plant 100 according to an embodiment of the present invention. The asphalt mixing plant 100 includes a plurality of devices 10 for producing asphalt. Such devices 10 may include, for example, cold feeders, filters, recycled filler bins, dryers, burners, mixing towers, and asphalt and fuel systems.

[0096] The devices 10 may each include one or more processing sensors 11, which are also indicated as processing sensors S in Figure 1 The processing sensors 11 sense or measure the processing parameters of the devices 10 of the asphalt mixing plant 100.

[0097] The asphalt mixing plant 100 further includes an emission measurement unit 20, which is also denoted as EM and is configured to measure the current emissions of the asphalt mixing plant 100. The emission measurement unit 20 may be particularly arranged at the exhaust pipe 30 of the asphalt mixing plant. According to an embodiment, the asphalt mixing plant 100 may include a plurality of exhaust pipes 30 and a plurality of associated emission measurement units 20. The exhaust pipe 30 may generally represent any part of the asphalt mixing plant that emits exhaust gas.

[0098] In addition, the plant 100 includes a control unit 40, which includes an emission prediction unit 41, which is also denoted as EP. The control unit 40 is configured to receive and process the current emission value EV measured by the emission measurement unit 20, and to receive and process the processing parameters PP from the plurality of processing sensors 11.

[0099] The control unit 40 (more particularly, the emission prediction unit 41) is configured to calculate a prediction of the average emission value of one or more target substances within a predefined target time interval. The control unit 40 is configured to observe the prediction and, if, according to the prediction of the emission prediction unit 41, it is expected that the predefined threshold value of the average emission value within the predefined target interval of one or more target substances is exceeded, then initiate and execute an alarm process.

[0100] The control unit 40 further includes a display unit 42, a memory 43, and a processor 44.

[0101] The plurality of devices 10 includes control elements 12 (also denoted as CE) to control the operating parameters of the devices 10. This allows actions (particularly control actions) to be initiated to control and change the operation of the devices 10 in order to reduce emissions and keep the emissions below the corresponding threshold values of the average emissions of one or more target substances within the corresponding target time intervals. Control signals CS are exchanged between the control unit 40 and the control elements CE.

[0102] The operating parameters processed by the sensor 11 can be, for example, the temperature, pressure, feed rate of the device 11 or its components, or other operating parameters that may affect the emissions of the station 100. More particularly, the measured parameters can include: the clean gas air flow, the VA and RA burner loads and feed rates, the VA, RA, and asphalt mixing temperatures, the asphalt type, the fuel type, and the corresponding asphalt mixing formula.

[0103] The emission measurement unit 20 can be configured to measure CO, NO as emissions x , SO x , VOC-C1, O2, H2O, and / or dust.

[0104] The control unit 40 can analyze the measurement data (particularly the emission values measured by the emission measurement unit) according to the current version of the relevant regulations or provisions of the responsible local authority. In addition, the visualization can be displayed on the display unit 42. In addition, the predicted trend of the average emission value can be displayed. Exceeding the threshold will trigger an alarm process and subsequent actions to reduce emissions, as will be explained in more detail below.

[0105] The control unit 40 can provide the following 3 color codes to a "traffic light system":

[0106] - Green (everything is normal, no action required)

[0107] - Orange (action phase 1)

[0108] - Red (action phases 2 and 3)

[0109] The emission prediction unit 41 is also capable of generating production and / or emission reports for VOC-C1, for example, with reference to the type of asphalt mixture formulation.

[0110] In addition, the asphalt mixing plant 100 includes an end-of-pipe (EOP) unit 50 (such as a VOC filter) and an active treatment unit 55 (such as a unit for lime injection) at the exhaust pipe 30. The end unit 50 and the active treatment unit 55 can be controlled by the control unit 40 by means of a control signal CS. In addition, the end unit 50 and the active treatment unit 55 can provide treatment parameters PP to the control unit. The emission measurement device 20 measures the emissions after the end (EOP) unit 50.

[0111] Figure 2 A more detailed embodiment of the emission measurement unit 20 is shown. The emission measurement unit 20 includes a plurality of measurement sensors 21, which may include, for example, a VOC-C1 sensor, an oxygen (O2) sensor, an H2O sensor, and sensors for additional other components. The emission measurement unit 20 also includes a processor 22 for processing sensor data from the sensors 21, a memory 23, and an interface 24 for providing the measured emission data / emission values to the control unit 40.

[0112] The data provided from the emission measurement unit 20 to the control unit 40 can come directly from the sensors of the emission measurement unit 20 (such as a VOC-C1 sensor or an O2 sensor) or from the processor 22. The process sensors 11 of the asphalt mixing plant 100 provide the necessary operating parameters.

[0113] Figure 3 and Figure 4 A flowchart of a method for operating an asphalt mixing plant (such as the asphalt mixing plant 100 as Figure 1 shown) is shown.

[0114] More particularly, Figure 3 the method steps performed by the emission measurement unit 20 and the process sensors 11 are shown, while Figure 4 the method steps performed by the process sensors 11 and by the control unit 40 based on the data received from the emission measurement unit 20 are illustrated.

[0115] At step 310, the emission measurement unit 20 measures the current emissions of the asphalt mixing plant and provides the measured current emission value to the control unit 40 at step 320.

[0116] At step 330, the process sensors 11 sense the process parameters of the device 10 and provide the process parameters to the control unit 40 at step 340.

[0117] At step 350, the control unit 40 receives the current emission value from the emission measurement unit 20, receives the process parameters from the plurality of process sensors 11, and calculates a prediction of the average emission value of one or more target substances within one or more predefined target time intervals.

[0118] Steps 310 - 350 are performed continuously and / or at intervals, and at step 350, input data for a control method to be executed in parallel on the control unit 40 is provided, and the control method is shown in more detail in Figure 4 which is shown in more detail in

[0119] At step 410, the emission prediction unit 41 of the control unit 40 calculates a prediction of the average emission value of one or more target substances within one or more predefined target time intervals, and checks whether one or more predefined thresholds of the average emission value will be exceeded according to the prediction of the emission prediction unit 41.

[0120] Step 410 can be performed simultaneously for a plurality of target substances. According to an embodiment, CO, NO x SO x O2, H2O, VOC - C1, and dust can be measured as target substances by the emission measurement unit 20 and observed by the control unit 40.

[0121] The predefined target time intervals can have various lengths. In particular, the preferred target time intervals can have a length of 30 minutes and a length of 1 calendar day.

[0122] According to a preferred embodiment, the control unit 40 calculates the prediction of the average emission value within the first target time interval and the prediction of the average emission value within the second target time interval in parallel.

[0123] Hereinafter, it is assumed that the control unit calculates the prediction of the average emission value (also denoted as the half - hour average value HAV) within the target time interval of 30 minutes and the prediction of the average emission value (also denoted as the daily average value DAV) within the target time interval of 1 calendar day in parallel at step 410.

[0124] If it is predicted according to the calculation at step 410 that the thresholds of HAV and / or DAV will be exceeded, then the control unit 40 starts to execute an alarm process to reduce emissions. The alarm process is a staggered alarm process that starts from the first stage at step 420. In the first stage, a first set of actions is performed. In particular, the control unit 40 issues a warning to the operator of the asphalt mixing plant that HAV and / or DAV will be exceeded as an alarm message on the display unit 42. In addition, the control unit 40 starts a timer after entering the first stage.

[0125] In addition, the control unit 40 issues a plurality of action suggestions to the operator on the display unit 42 in the first stage. The action suggestions depend on the target substance and the measured process parameters of the treatment sensor 11. To determine the most suitable suggestion, the control unit 40 can use an action matrix, which is stored in the memory 43 of the control unit as a look-up table.

[0126] The suggestions shown by the control unit 40 can be triggered by the responsible treatment sensor 11. For example, if the material temperature of the recycled asphalt is too high, a suggestion to reduce the material temperature of the recycled asphalt will be displayed.

[0127] The action suggestions issued by the control unit 40 depend on the corresponding target substance that is expected to be exceeded. Some preferred action suggestions for selecting the preferred target substance are given below.

[0128] For the target substance of VOC-C1, the following action suggestions can be issued:

[0129] - Reduce the RA feed rate and increase the VA feed rate;

[0130] - Adjust the addition order of the materials in the mixing cycle;

[0131] - Reduce the RAH material temperature, especially the RAH material outlet temperature;

[0132] - Reduce the asphalt mixture temperature;

[0133] - Reduce the RAH and / or RAC content in the asphalt mixture production;

[0134] - Check the burner settings; and / or

[0135] - Check the VA and / or RAH cylinders.

[0136] For the target substance of CO, the following action suggestions can be issued:

[0137] - Check the burner settings; and / or

[0138] - Change the burner load(s).

[0139] For the target substance of NO x the following action suggestions can be issued:

[0140] - Check the burner settings;

[0141] - Change the burner load(s); and / or

[0142] - Check the fuel characteristics (supplier and / or laboratory).

[0143] For the target substance of SO xFor the target substance, the following action suggestions can be issued:

[0144] - Check the fuel characteristics (supplier and / or other laboratories); and / or

[0145] - Check the aggregate properties (supplier and / or laboratory).

[0146] Then, the operator will perform the corresponding actions to reduce emissions.

[0147] Then, at step 430, the control unit periodically checks whether the timer has expired. Then, when the timer expires, the control unit evaluates / checks whether the predefined threshold corresponding to the target time interval, such as HAV and / or DAV, will still be exceeded according to the latest prediction calculated by the emission prediction unit 41.

[0148] If it is predicted that the threshold will no longer be exceeded, then the actions in the first stage can be automatically closed by the operator or by the control unit at step 445.

[0149] If it is predicted that one or more thresholds will still be exceeded, then the control unit 40 will automatically enter the second stage. Then, at step 450, the control unit 40 will perform a second set of actions.

[0150] In particular, the control unit 40 issues a warning to the operator of the asphalt mixing plant on the display unit 42 that the HAV and / or DAV is expected to be exceeded as an alarm message. In addition, the control unit 40 starts a timer after entering the second stage.

[0151] In addition, the control unit 40 automatically changes one or more operating parameters of one or more of the plurality of devices 10 of the asphalt mixing plant.

[0152] These automatic actions are performed independently of the operator and take into account the current operating state of the device 10 sensed by the processing sensor 11.

[0153] To determine the most appropriate action, the control unit 40 can again use the action matrix stored in the memory 43 of the control unit 40 as a look-up table.

[0154] The actions automatically performed by the control unit 40 depend on the corresponding target substance expected to be exceeded. In addition, these actions depend on the corresponding configuration of the asphalt mixing plant, especially whether the asphalt mixing plant is processing cold recycled asphalt or hot recycled asphalt. While hot recycled asphalt is added to the mixer via a separate drum, cold recycled asphalt can be added directly to the mixer.

[0155] In the following, some preferred action suggestions are given for selecting the preferred target substances and configurations of the asphalt mixing plant:

[0156] For a station for processing hot recycled asphalt, the following can be done to reduce VOC-C1:

[0157] - Prevent an increase in the burner load(s); and / or

[0158] - Reduce the RAH material temperature to an adjustable target temperature; and / or

[0159] - Adjust the burner load according to the adjustable target material temperature of the hot recycled asphalt, in particular the burner load of the burner of the virgin aggregate silo and / or the burner load of the burner of the recycled asphalt silo; and / or

[0160] - Reduce the RAH feed rate by a certain percentage (e.g., 20%, default value) below the actual feed rate, including reducing the burner load of the burner of the recycled asphalt silo; and / or

[0161] - Reduce the RAH dosing rate by a certain percentage (e.g., 20%, default value) below the actual RAH dosing rate.

[0162] For a station for processing cold recycled asphalt, the following can be done to reduce VOC-C1:

[0163] - Reduce the RAC dosing rate by a certain percentage (e.g., 20%, default value) below the actual RAC dosing rate; and / or

[0164] - Send information to the operator to check the asphalt mixing recipe parameters (time points and durations of RAC addition and new asphalt addition; opening points of steam valves).

[0165] For the target substances CO and NO x , only additional equipment can be used to take automatic actions. According to some embodiments, the asphalt mixing station includes such additional equipment, for example, a lambda probe. In addition, the manual measures recommended to the operator in the first stage can be issued again.

[0166] Subsequently, at step 460, the control unit 40 periodically checks whether the timer has expired. Then, when the timer expires, the control unit at step 470 evaluates / checks according to the latest prediction calculated by the emission prediction unit 41 whether the predefined threshold of the corresponding target time interval, e.g., HAV and / or DAV, will still be exceeded.

[0167] If it is predicted that the threshold will no longer be exceeded, then the actions in the second stage can be automatically turned off by the operator or by the control unit at step 445.

[0168] If it is still predicted to exceed one or more thresholds, then the control unit 40 will automatically enter the third stage. Then, at step 480, the control unit 40 will perform a third set of actions. The third set of actions is preferably an end-of-pipe action and / or an active treatment step for reducing emissions. More particularly, in the third stage, filtering and / or exhaust gas treatment measures are automatically activated to reduce emissions.

[0169] It should be noted that stage 3 actions are only taken if a corresponding end-of-pipe solution (e.g., a VOC filter) or an active treatment facility (e.g., lime injection) is installed according to an embodiment of the present invention.

[0170] Stage 3 actions also include issuing a warning on the display unit 42 that the corresponding thresholds (HAV, DAV) will be exceeded and that the end-of-pipe action or the active treatment step will be automatically activated.

[0171] Furthermore, the warning includes a message or instruction on the display unit 42 that the production process / asphalt mixing process must be adjusted according to the exhaust gas treatment recommendations. This may involve the need to reduce production capacity.

[0172] According to an embodiment, the control unit 40 may include adjustable settings that can be adjusted by the customer / operator of the asphalt mixing plant according to their requirements. In particular, the logic of the control unit 40 for switching between stage 2 and stage 3 actions can be adjusted according to the customer's requirements. As an example, if an end-of-pipe solution is installed, it may be more economical for the operator of the plant to use as much reclaimed asphalt pavement as possible and keep the end-of-pipe installation open, rather than saving the capacity / life of the end-of-pipe facility by not using it.

[0173] According Figure 4 to an embodiment, it is assumed that the end-of-pipe action and / or the active treatment step will continue until the end of the HAV period monitored at step 485. However, according to other embodiments, a timer may also be started after entering the third stage, and it may be checked whether the HAV threshold will still be exceeded after the timer expires.

[0174] If the current HAV period has expired, then at step 490 it is checked according to the latest prediction whether the DAV will still be exceeded. If the DAV will still be exceeded, then the actions in stage 3 will continue until the prediction of the DAV is also below the threshold.

[0175] If this is the case, then at step 495, all current actions that have been automatically initiated in the second and / or third stage will be closed.

[0176] According to a further embodiment, as a further stage, for example as a fourth stage, the feeding of recycled bitumen to the asphalt mixing plant may be stopped. According to a preferred embodiment, the focus will be on the main reasons for exceeding the emission target substances. For example, if the VOC will be exceeded, then the feeding and / or dosing of recycled bitumen may be shut off.

[0177] If no action will result in a reduction of VOC emissions and it is inevitable that the HAV or DAV will be exceeded, then the addition of any hot or cold recycled bitumen will be stopped during the corresponding period. More particularly, if the HAV will be exceeded, then the addition of any hot or cold recycled bitumen will be blocked until the end of the HAV period. And if the DAV will be exceeded, then the addition of any hot or cold recycled bitumen will be blocked throughout the calendar day.

[0178] Figure 5 shows a diagram Figure 1 illustrating a calculation example of the prediction of the average emission value performed by the emission prediction unit 41.

[0179] The x-axis represents the time t of the target time interval. For example, the target time interval is a half-hour interval, and thus, the control unit of the asphalt mixing plant should ensure that the average emission value HAV should not be exceeded within this target time interval.

[0180] The y-axis represents the concentration of the target substance such as VOC-C1, in mg / m 3 as the unit.

[0181] In this example, the threshold value of the average emission value within the target time interval is 50 mg / m 3 .

[0182] The emission prediction unit 41 determines the intermediate average emission value measured within a sub-interval of, for example, 5 minutes. In other words, after every 5 minutes, the emission prediction unit determines the average emission value within the most recent 5 minutes. These intermediate average emission values are shown in Figure 5 by the hatched areas and are denoted by the reference numerals 510 - 515.

[0183] According to an embodiment, the emission prediction unit 41 may use different methods to calculate the prediction.

[0184] According to an embodiment, the prediction unit 41 uses linear prediction as the first prediction method. According to this example, the linear prediction is based on a linear extrapolation of the measured intermediate average emission values within a 5-minute sub-interval 510 - 515. The linear prediction generates a prediction curve, which, according to this example, is updated every 5 minutes and is shown as a dashed line. In this example, the linear prediction curve includes linear prediction results 520, 521, 522, 523, 524, and 525. The linear prediction results 520, 521, 522, 523, 524, and 525 according to this example use the center of each sub-interval as the basis for linear prediction. According to other embodiments, the start or end of each sub-interval can be used for linear prediction. Linear prediction is quite sensitive to changes in the measured emission values. As an example, the average emission value of the first sub-interval 510 within the time period from 0 to 5 minutes is 30 mg / m 3 , and the average emission value of the second sub-interval 511 within the time period from 5 to 10 minutes is 40 mg / m 3 . The linear extrapolation of these two values provides a linear prediction 521, which exceeds the threshold of 50 mg / m 3 during the target time interval of 30 minutes. This linear extrapolation is used as the prediction for entering the first stage. Therefore, after 10 minutes, the control unit 40 will start to execute the alarm process with the first set of actions in the first stage. Thus, the linear prediction establishes an early warning, which particularly allows for starting with actions having a low impact depth on asphalt production. As Figure 5 can be seen, even though the average emission value of the second sub-interval 511 is still significantly lower than the threshold of 50 mg / m 3 at 40 mg / m 3 , the actions in the first stage have been entered at the end of the second sub-interval 511.

[0185] To decide to enter the second stage and possibly the third stage, another prediction method is used, which is hereinafter referred to as the second prediction method. The second prediction method uses the corresponding measured intermediate average emission values within the latest 5-minute sub-interval for prediction. Therefore, entry into the second stage and possibly the third stage occurs only when the threshold calculated according to the second prediction method is exceeded. Thus, in this example, entry into the second stage occurs only when the average emission value of the 5-minute sub-interval is higher than 50 mg / m 3 .

[0186] In this example, this first occurs in the third interval 512 between 10 and 15 minutes. Therefore, after 15 minutes, the control unit 40 automatically enters the second stage and executes the second set of actions for reducing emissions.

[0187] In Figure 5In the example, the fourth interval 513 between 15 and 20 minutes is also higher than the threshold of 50 mg / m 3 , while in the fifth interval 514 and the sixth interval 515, the average emission value returns below the threshold, indicating that the actions taken are successful.

[0188] To decide whether to close an initiated action, the control unit 40 can generally use multiple possible decision logics.

[0189] According to Figure 5 the preferred logic shown, the control unit 40 closes the action only when the predicted average emission value within a half-hour interval is expected to become lower than 50 mg / m according to the prediction based on the first prediction method (linear prediction) and the prediction based on the second prediction method (average value of the latest sub-interval). 3 Therefore, the linear prediction must become lower than the threshold for closing the action, and the latest average emission value of the latest 5-minute sub-interval must be lower than the threshold for closing the action.

[0190] In Figure 5 the example, this occurs after 25 minutes. Then, between 20 and 25 minutes, the linear prediction 524 is lower than the threshold, and the latest average emission value of the sub-interval 514 is lower than the threshold.

[0191] This switching logic that depends on two predicted values based on two different prediction methods has been shown to ensure maintaining the corresponding threshold and not closing the action too early in a reliable manner.

[0192] Figure 6 shows a diagram illustrating another embodiment of the calculation of the prediction of the average emission value performed by the Figure 1 emission prediction unit 41.

[0193] The x-axis also represents the time t of the target time interval of half an hour. Therefore, the control unit of the asphalt mixing plant should ensure that the average emission value HAV is not exceeded within this target time interval.

[0194] The y-axis represents the concentration of the target substance such as VOC-C1, in mg / m 3 units.

[0195] In this example, the threshold of the average emission value within the target time interval is also 50 mg / m 3 .

[0196] The emission prediction unit 41 determines the intermediate average emission value measured within a 5-minute sub-interval. In other words, after every 5 minutes, the emission prediction unit determines the average emission value within the most recent 5 minutes. These intermediate average emission values are shown by the dashed line 630, which interpolates the respective intermediate average emission values determined at 5, 10, 15, 20, 25, and 30 minutes.

[0197] According to this embodiment, the prediction unit 41 also uses linear prediction as the first prediction method. According to this embodiment, linear prediction is based on linear extrapolation of the measured intermediate average emission values of the 5-minute sub-intervals 610-615. The linear prediction generates a prediction curve, which is updated every 5 minutes according to this example and is shown as a dashed line. In this example, the linear prediction curve includes linear prediction results 620, 621, 622, 623, 624, and 625. The linear prediction results 620, 621, 622, 623, 624, and 625 according to this example use the start (or in other words, the starting point) of the corresponding sub-interval as the time basis for linear prediction. As an example, the average emission value of the first sub-interval 610 in the time period from 0 to 5 minutes is 30 mg / m 3 , and the average emission value of the second sub-interval 611 in the time period from 5 to 10 minutes is 40 mg / m 3 . The linear extrapolation of these two values starts from the start of sub-intervals 610 and 611 respectively, providing a linear prediction result 621, which exceeds the 50 mg / m 3 threshold during the 30-minute target time interval. This linear extrapolation is used as the prediction for entering the first stage. Therefore, after 10 minutes, the control unit 40 will start to execute the alarm process with the first set of actions in the first stage. Thus, linear prediction establishes an early warning, which especially allows for starting with actions having a low impact depth on asphalt production. As Figure 6 can be seen, even though the average emission value of the second sub-interval 611 is 40 mg / m 3 , which is still significantly lower than the 50 mg / m 3 threshold, the actions in the first stage have already been entered at the end of the second sub-interval 611.

[0198] To decide to enter the second stage and possibly the third stage, another prediction method is used, which is hereinafter referred to as the third prediction method. Compared with the second prediction method described with reference Figure 5 , the third prediction method uses the measured current average emission values of all previous 5-minute sub-intervals during the 30-minute target time interval as the prediction. These measured average current emission values of all previous sub-intervals are shown by the curve 640. Therefore, entry into the second stage and possibly the third stage only occurs when the threshold calculated according to the third prediction method is exceeded. Thus, in this example, entry into the second stage only occurs when the average emission values of all previous 5-minute sub-intervals of the 30-minute target time interval are higher than 50 mg / m 3 .

[0199] In this example, this occurs for the first time after the fourth interval 613. More specifically, the average emission values of sub-intervals 610, 611, 612, and 613 are 30 mg / m 3 , 40 mg / m 3 , 65 mg / m 3 and 80 mg / m 3 . The average of these four sub-intervals is approximately 54 mg / m 3 , thus exceeding the threshold of 50 mg / m 3 . Accordingly, after 20 minutes, the control unit 40 automatically enters the second phase and executes a second set of actions for reducing emissions.

[0200] In the Figure 6 example, after the fifth interval 614, the average emission value of the previous 5 sub-intervals 610 - 614 is 49 mg / m 3 , which has returned below the threshold, indicating that the actions taken have been successful.

[0201] To decide whether to turn off the initiated actions, similarly, the control unit 40 can generally use multiple possible decision logics.

[0202] According to a preferred logic, the control unit 40 turns off the actions only when the predicted average emission value within a half-hour interval becomes lower than the threshold of 50 mg / m 3 both according to the prediction according to the first prediction method (linear prediction) and according to the prediction according to the third prediction method (average of all previous sub-intervals of the current target time interval). Thus, the linear prediction must become lower than the threshold for turning off the actions, and the average emission value of the 5-minute previous sub-intervals of the corresponding 30-minute target time interval must be lower than the threshold for turning off the actions.

[0203] In the Figure 6 example, this occurs after 25 minutes. Then, the linear prediction 624 is lower than the threshold, and the average emission value of 49 mg / m 3 for sub-intervals 610 - 614 is lower than the threshold.

[0204] According to a further embodiment, the decision logic for entering the respective phases (first phase, second phase, third phase, and further phases) can include other suitable combinations of the first prediction logic, the second prediction logic, and the third prediction logic.

[0205] According to one embodiment, the control unit can enter the second phase only when it is predicted to exceed the threshold according to the second prediction method and the third prediction method. Similarly, the control unit can enter the third phase only when it is predicted to exceed the threshold according to the second prediction method and the third prediction method.

[0206] According to a further embodiment, the decision logic for the shutdown action may include other suitable combinations of a first prediction logic, a second prediction logic, and a third prediction logic.

[0207] According to an embodiment, the control unit 40 may only shut down the action when the average emission value within a half-hour interval is predicted to be lower than a threshold value of 50 mg / m 3 according to the first prediction method, the second prediction method, and / or the third prediction method and / or another prediction method.

[0208] Figure 7 A simplified flowchart 700 of an asphalt mixing process according to an embodiment of the present invention is illustrated by way of example. The asphalt mixing plant includes a plurality of VA cold feeder units 701, a VA drying / heating drum 702 including a burner, a filter 703, an exhaust blower 704, and an exhaust pipe 705. The asphalt mixing plant further includes a recycled filler elevator 706, an intermediate recycled filler bin 707, a recycled filler bin 708, an inlet filler bin 709, a filler scale 710, and a VA elevator 711, a screen 712, a hot VA bin 713, and a VA scale 714. The asphalt mixing plant further includes a hot recycled asphalt (RAH) addition machine, which includes a plurality of (cold) RA feeder units 715, an RA elevator 716, an RA drying / heating drum 717 including a burner, an RAH buffer bin 718 with weighing means, and an RAH scale 719. In addition, the asphalt mixing plant includes a cold recycled asphalt (RAC) addition machine, which includes a plurality of (cold) RA feeder units 720, an RA buffer bin 721, and an RA belt scale 722. The asphalt mixing plant further includes a plurality of asphalt tanks 723 and an asphalt scale 724. The asphalt mixing plant further includes a mixer 725, a hopper 726, and a plurality of asphalt mixture storage bins 727.

[0209] Figure 8 An embodiment of an action matrix 800 is shown, which may be stored, for example, in Figure 1 a memory unit 43. The action matrix establishes a lookup table or, in other words, decision logic based on which the control unit 40 can decide which actions must be taken for the various stages of the alarm process.

[0210] The action matrix 800 includes a column 801 having three stages: "Stage 1", "Stage 2", and "Stage 3".

[0211] Column 802 represents the various target substances / target gases to be observed, in this example VOC-C1, CO, NO x and SO xColumn 803 includes a plurality of actions to be taken depending on the phase and the target substance. It should be noted that for two or more target substances, a particular action may be the same, and thus may appear multiple times in column 803.

[0212] Additionally, the action matrix 800 includes a plurality of additional columns, in this example 11 additional columns, collectively referred to as column 804. Each column 804 represents a combination of possible asphalt mixing plant types. More particularly, according to this example, the action matrix 700 includes 11 different asphalt mixing plant types. For each of the 11 different plant types, a cross indicates that the corresponding action applies to the respective plant type, while a dash indicates that the corresponding action does not apply to the respective plant type.

[0213] The plant type particularly indicates whether RA is used and which recycling method is used. Possible recycling methods include RAC, according to which cold RA is directly added to the mixer, and according to RAH, the cold recycled asphalt is dried and heated and added in a hot state. According to the RAH method, the cold RA can be added via a loop to the original aggregate drying / heating drum and dried and heated therein, or a separate (so-called parallel or RAH) recycled asphalt drying / heating drum can be used for co-current or counter-current operation to dry and heat the recycled asphalt.

[0214] Aspects of the present invention can be implemented as a system (particularly an asphalt mixing plant), a method, and / or a computer program product. The computer program product can include one or more computer-readable storage media having computer-readable program instructions thereon for causing a processor (particularly the processor 44 of the control unit 40) to execute aspects of the present invention.

[0215] A computer-readable storage medium can be a tangible device that can hold and store instructions for use by an instruction execution device. A computer-readable storage medium can be, for example but not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. A non-exhaustive list of more specific examples of computer-readable storage media includes: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disc (DVD), a memory stick, a floppy disk, a mechanically encoded device (such as a punched card or raised structures in grooves having instructions recorded thereon), and any suitable combination of the above. As used herein, a computer-readable storage medium should not be construed as an instantaneous signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., an optical pulse through an optical fiber cable), or an electrical signal transmitted through a wire.

[0216] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to a corresponding computing / processing device, or downloaded to an external computer or external storage device via a network (e.g., the Internet, a local area network, a wide area network, and / or a wireless network). The network can include copper transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in a computer-readable storage medium within the corresponding computing / processing device.

[0217] The computer-readable program instructions for performing the operations of the present invention may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state-setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages (such as Smalltalk, C++, etc.) and conventional procedural programming languages (such as the "C" programming language or similar programming languages). The computer-readable program instructions may be executed entirely on the user's computer, partially on the user's computer, executed as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the latter case, the remote computer may be connected to the user's computer through any type of network (including a local area network (LAN) or a wide area network (WAN)), or may be connected to an external computer (e.g., through the Internet using an Internet service provider). In some embodiments, an electronic circuit system, including, for example, a programmable logic circuit system, a field-programmable gate array (FPGA), or a programmable logic array (PLA), may execute the computer-readable program instructions by utilizing the state information of the computer-readable program instructions to personalize the electronic circuit system in order to perform aspects of the present invention.

[0218] Aspects of the present invention are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0219] These computer-readable program instructions may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, when executed via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions / actions specified in the flowchart and / or one or more block diagram blocks. These computer-readable program instructions may also be stored in a computer-readable storage medium that can direct a computer, a programmable data processing apparatus, and / or other devices to function in a particular manner, such that the computer-readable storage medium in which the instructions are stored comprises a manufacture, the manufacture including instructions for implementing aspects of the functions / actions specified in the flowchart and / or one or more block diagram blocks.

[0220] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus, or other devices to produce a computer-implemented process such that the instructions executed on the computer, other programmable apparatus, or other devices implement the functions / acts specified in the flowchart and / or one or more block diagrams of the block(s).

[0221] The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagram may represent a module, segment, or portion of instructions, which includes one or more executable instructions for implementing the specified (one or more) logical functions. In some alternative implementations, the functions noted in the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It should also be noted that each block of the block diagrams and / or flowchart and combinations of blocks in the block diagrams and / or flowchart may be implemented by a special purpose system based on hardware that performs the specified functions or acts or a combination of special purpose hardware and computer instructions.

[0222] While the present invention has been shown and described with reference to the presently preferred embodiments, it should be clearly understood that the present invention is not limited thereto, but may be otherwise variously embodied and practiced within the scope of the appended claims.

Claims

1. An asphalt mixing plant, comprising: a plurality of devices (10); an emission measurement unit (20) configured to measure the current emissions of the asphalt mixing plant and provide a current emission value; a plurality of process sensors (11), the process sensors (11) being configured to sense process parameters of the devices (10) of the asphalt mixing plant; a control unit (40) including an emission prediction unit (41), the control unit (40) being configured to: receive and process the current emission value from the emission measurement unit (20); receive and process the process parameters from the plurality of process sensors (11); calculate, by the emission prediction unit (41), a prediction of the average emission value of one or more target substances within a predefined target time interval based on the measured current emission value; and if, according to the prediction of the emission prediction unit (41), it is expected to exceed a predefined threshold of the average emission value within the predefined target interval, then perform an alarm process, the alarm process including a plurality of actions for reducing emissions, wherein the emission prediction unit (41) is configured to: calculate a linear prediction of the measured emission values within a sub-interval of the target interval based on linear extrapolation by a first prediction method, in particular a linear prediction of the measured intermediate average emission value; and / or calculate the measured intermediate average emission value of the latest sub-interval of the target interval by a second prediction method; and / or calculate the measured current average emission value of the previous sub-interval of the target interval by a third prediction method.

2. The asphalt mixing plant according to claim 1, wherein the alarm process is a staggered alarm process, the staggered alarm process including at least a first stage and a second stage, wherein the control unit (40) is configured to perform a first set of actions for reducing emissions in the first stage and a second set of actions for reducing emissions in the second stage.

3. The asphalt mixing plant according to claim 2, wherein the staggered alarm process includes a third stage, wherein the control unit (40) is configured to perform a third set of actions for reducing emissions in the third stage.

4. The asphalt mixing plant according to claim 3, wherein the staggered alarm process includes a fourth stage, wherein the control unit (40) is configured to perform a fourth set of actions for reducing emissions in the fourth stage.

5. The asphalt mixing plant according to any one of claims 2 to 4, wherein the first set of actions includes actions that are less destructive to the continued operation of the asphalt mixing plant than the actions in the second set of actions; and / or the second set of actions includes actions that are less destructive to the continued operation of the asphalt mixing plant than the actions in the third set of actions; and / or the third set of actions includes actions that are less destructive to the continued operation of the asphalt mixing plant than the actions in the fourth set of actions.

6. The asphalt mixing plant according to any one of claims 2 to 4, wherein the staggered alarm process includes: starting a timer after entering the first stage; evaluating, when the timer expires, whether the predefined threshold will still be exceeded according to the current prediction of the emission prediction unit; automatically entering the second stage if, according to the latest prediction of the emission prediction unit, the predefined threshold of the average emission value will still be exceeded; and If the latest prediction of the emission prediction unit no longer exceeds a predefined threshold, then terminate the actions of the first stage.

7. The asphalt mixing plant according to any one of claims 3 to 4, wherein the staggered alarm process comprises: Starting a timer after entering the second stage; When the timer expires, evaluating whether the predefined threshold will still be exceeded according to the latest prediction of the emission prediction unit; If, according to the latest prediction of the emission prediction unit, the predefined threshold of the average emission value will still be exceeded, then automatically enter the third stage; and If the latest prediction according to the emission prediction unit no longer exceeds the predefined threshold, then terminate the actions of the first stage and the second stage.

8. The asphalt mixing plant according to any one of claims 2 to 4, wherein the first set of actions, the second set of actions, the third set of actions and / or the fourth set of actions include sending an alarm message to an operator of the asphalt mixing plant.

9. The asphalt mixing plant according to any one of claims 2 to 4, wherein the first set of actions and / or the second set of actions include sending one or more action suggestions to an operator of the asphalt mixing plant, wherein the control unit (40) is configured to send action suggestions according to current operating parameters.

10. The asphalt mixing plant according to any one of claims 2 to 4, wherein the first set of actions and / or the second set of actions include automatically changing operating parameters of one or more of the plurality of devices (10) of the asphalt mixing plant by the control unit (40).

11. The asphalt mixing plant according to any one of claims 3 to 4, wherein the third set of actions includes automatically initiating end actions and / or active treatment steps by the control unit (40) to reduce emissions.

12. The asphalt mixing plant according to claim 4, wherein the third set of actions or the fourth set of actions includes stopping any feeding and dispensing of recycled asphalt to the asphalt mixing plant and / or the asphalt mixture.

13. The asphalt mixing plant according to claim 1, wherein the control unit (40) includes a memory (43), and wherein the memory (43) is configured to store a look-up table (700), the look-up table including an action matrix.

14. The asphalt mixing plant according to claim 1, wherein the control unit (40) is configured to: If it is predicted according to the first prediction method that the threshold will be exceeded, then enter the first stage; If it is predicted according to the second prediction method and / or the third prediction method that the threshold will be exceeded, then enter the second stage; and / or If it is predicted according to the second prediction method and / or the third prediction method that the threshold will be exceeded, then enter the third stage.

15. The asphalt mixing plant according to claim 1 or 14, wherein the control unit (40) is configured to: If it is predicted that the threshold becomes lower than the threshold according to the first prediction method and according to the second prediction method; or the threshold according to the first prediction method and according to the third prediction method; or the threshold according to the first prediction method, the second prediction method and the third prediction method; then turn off any actions of the alarm process, in particular the actions of the first stage, the second stage and / or the third stage.

16. The asphalt mixing plant according to claim 2 or 14, wherein the first set of actions is selected from the group consisting of: reducing the feed rate of the recycled asphalt and increasing the feed rate of the virgin aggregates; checking the burner settings of the burner of the asphalt mixing plant; reducing the material temperature of the hot recycled asphalt, in particular the outlet material temperature; reducing the asphalt mixture material temperature of the asphalt mixture in the mixer of the plant; and reducing the content of recycled asphalt in the asphalt mixture material.

17. The asphalt mixing plant according to claim 2 or 14, wherein the second set of actions is selected from the group consisting of: preventing an increase in the burner load of the burner of the asphalt mixing plant, in particular the burner load of the burner of the virgin aggregate silo and / or the burner of the recycled asphalt silo; reducing the material temperature of the hot recycled asphalt to an adjustable target temperature; adjusting the burner load according to the adjustable target material temperature of the hot recycled asphalt, in particular the burner load of the burner of the virgin aggregate silo and / or the burner load of the burner of the recycled asphalt silo; reducing the feed rate of the recycled asphalt by a predefined percentage; and reducing the dosing rate of the cold recycled asphalt and / or the hot recycled asphalt by a predefined percentage.

18. The asphalt mixing plant according to claim 1 or 14, wherein the emission prediction unit (41) is configured to periodically and in parallel calculate one or more predictions of the average emission value within a first target time interval and one or more predictions of the average emission value within a second target time interval, wherein the second target time interval is longer than the first target time interval.

19. The asphalt mixing plant according to claim 18, wherein the first target time interval is a 30 - minute time interval and the second target time interval is a 1 - calendar - day time interval.

20. A method for operating an asphalt mixing plant, the asphalt mixing plant comprising a plurality of devices (10), an emission measurement unit (20), a plurality of process sensors (11), and a control unit (40) including an emission prediction unit (41), the method comprising: measuring, by the emission measurement unit (20), the current emissions of the mixing plant; providing, by the emission measurement unit (20), the current emission value to the control unit; sensing, by the process sensors (11), the process parameters of the devices (10) of the asphalt mixing plant; receiving, by the control unit (40), the current emission value from the emission measurement unit (20); receiving, by the control unit (40), the process parameters from the plurality of process sensors (11); calculating, by the emission prediction unit (41), a prediction of the average emission value of one or more target substances within a predefined target time interval based on the measured current emission value; and if, according to the prediction of the emission prediction unit (41), it is expected to exceed a predefined threshold of the average emission value within a predefined target interval, then performing, by the control unit (40), an alarm process, wherein the emission prediction unit (41) is configured to: calculate, by a first prediction method based on linear extrapolation, a linear prediction of the measured emission values within a sub - interval of the target interval, in particular a linear prediction of the measured intermediate average emission value; and / or Calculate the measured intermediate average emission value of the latest sub-interval of the target interval by a second prediction method; and / or Calculate the measured current average emission value of the previous sub-interval of the target interval by a third prediction method.

21. A computer program product for operating a control unit (40) of an asphalt mixing plant, the control unit (40) comprising an emission prediction unit (41), the asphalt mixing plant comprising a plurality of devices (10), an emission measurement unit (20) configured to measure the current emissions of the asphalt mixing plant, and a plurality of process sensors (11), the computer program product comprising a computer-readable storage medium having program instructions embodied therewith, the program instructions being executable by the control unit to cause the control unit to perform a method comprising: Receiving, by the control unit (40), a current emission value from the emission measurement unit (20); Receiving, by the control unit (40), process parameters from the plurality of process sensors (11); Calculating, by the emission prediction unit (41), a prediction of the average emission value of one or more target substances within a predefined target time interval based on the measured current emission value; And If, according to the prediction of the emission prediction unit (41), it is expected that a predefined threshold of the average emission value within the predefined target interval is exceeded, then performing, by the control unit (40), an alarm process, wherein the emission prediction unit (41) is configured to: Calculate a linear prediction of the measured emission value within a sub-interval of the target interval, in particular a linear prediction of the measured intermediate average emission value, by a first prediction method based on linear extrapolation; and / or Calculate the measured intermediate average emission value of the latest sub-interval of the target interval by a second prediction method; and / or Calculate the measured current average emission value of the previous sub-interval of the target interval by a third prediction method.

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