Accurately-filled liquid air energy storage rock breaking method

Abstract

The invention discloses an accurately-filled liquid air energy storage rock breaking method which comprises the following steps: monitoring the flow of liquid air by adopting a clamping type ultrasonic flowmeter, and updating the injection amount in real time; a pressure sensor, an oxygen concentration sensor and a temperature sensor are adopted for liquid air leakage monitoring; the air volume can be monitored through the oxygen concentration change and the sensor, and the liquid air volatilization amount is calculated; performing pressure and temperature correction on the volume of the volatile gas, and calculating a volatilization rate; based on the liquid air injection amount and the volatilization amount, the liquid air storage amount in the blast hole is accurately calculated; data of all sensors are uniformly collected and summarized to a control center, and an embedded system is established to realize real-time data storage and processing; and when temperature sudden change or pressure abnormity is monitored, warning is performed, and transmission of liquid air is automatically closed. The device is used for the working conditions of water conservancy and hydropower, traffic, mine and other industries needing to pay attention to environmental protection, crushing effect and control degree, so that the liquid air energy storage rock breaking efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of blasting technology in water conservancy and civil engineering, and in particular to a method for rock breaking using precisely filled liquid air energy storage. Background Technology

[0002] Liquid air fracturing of rock mass, as a new blasting technology, has significant advantages over traditional blasting in terms of environmental friendliness, fracturing effect, and control. However, the volatile nature of liquid air at normal temperature and pressure causes vaporization loss after injection into the borehole. The liquid air content injected into the borehole continuously decreases and is difficult to measure. If the changes in the amount of liquid air injected and the amount of vaporization are not accurately estimated, the blasting effect of the rock mass cannot be guaranteed due to insufficient blasting energy release.

[0003] To fundamentally solve the problem of liquid air breaking rock, it is necessary to accurately calculate the amount of liquid air volatilized and stored in the blast hole from the perspective of energy storage, so as to provide more practical guidance for controlling the rock blasting effect.

[0004] Therefore, there is an urgent need to propose a new method for precise filling of liquid air energy storage for rock breaking to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies. In view of the current engineering technology status of existing liquid air rock breaking technology, which does not fully consider the impact of rock mass fissures, gasification loss and other factors on the loss of borehole reserves, this invention proposes an optimized design method for liquid air energy storage rock breaking that can be accurately filled, is simple to operate and saves time and effort.

[0006] This precise filling liquid air energy storage rock-breaking method includes the following steps:

[0007] S1. A clamp-on ultrasonic flow meter is used to monitor the liquid air flow rate and update the injection volume in real time.

[0008] S2. Use pressure sensors, oxygen concentration sensors, and temperature sensors to monitor liquid air leaks. Stop injection when the pipeline pressure, oxygen concentration in the air, and temperature are abnormal.

[0009] S3. By monitoring changes in oxygen concentration and using sensors, the volume of air can be measured, and the amount of liquid air evaporation can be calculated. Based on the ideal gas law, the volume of evaporating gas is corrected for pressure and temperature, and the evaporation rate is calculated.

[0010] S4. Based on the amount of liquid air injected and evaporated, accurately calculate the amount of liquid air stored in the borehole;

[0011] S5. Collect and summarize all sensor data in a unified manner at the control center, establish an embedded system to realize real-time data storage and processing, and generate detailed reports on the injection and evaporation of liquid air, including evaporation rate, total evaporation, pressure and temperature changes; when a sudden temperature change or abnormal pressure is detected, issue an alert and automatically shut down the transmission of liquid air.

[0012] In a preferred embodiment of this solution, the specific step of S1 is as follows: a clamp-on ultrasonic flow meter with non-contact measurement is used, which is placed outside the pipe by a clamp, and the flow velocity of the fluid in the pipe is measured by using sound wave conduction technology, thus avoiding direct contact with the fluid.

[0013] In a preferred embodiment of this solution, the specific steps of S2 are as follows: a pressure sensor is arranged on the inner wall of the injection port, close to the borehole, to monitor the pressure change in the pipe when liquid air is injected into the borehole; an oxygen concentration sensor and a temperature sensor are installed on the outer wall of the pipe injection port to ensure that the oxygen concentration and temperature are kept within a reasonable range during the liquid air injection process.

[0014] In a preferred embodiment of this scheme, the specific steps of S3 are as follows: select an electrochemical sensor suitable for low temperature as an oxygen concentration sensor, place it near the borehole, and use it to detect the concentration of volatilized oxygen, and accurately calculate the amount of volatilization by combining the gas volume, temperature and pressure.

[0015] Furthermore, the method for calculating the amount of volatiles:

[0016] Assuming the evaporated liquid air is an ideal gas, the calculation of the evaporation amount includes: ① measuring the gas volume and concentration; ② the amount of gas evaporation; ③ pressure and temperature corrections; ④ the evaporation rate.

[0017] ①Measure the volume and concentration of liquid air:

[0018] Oxygen volume: A gas sensor is used to monitor the volume of oxygen after the gas evaporates. Based on the ideal gas law, the changes in the gas state in the sensor's environment are analyzed.

[0019] The volume of the gas is calculated using the ideal gas law, as shown in equation (1):

[0020] (1)

[0021] In the formula: P is the gas pressure in Pa, and V is the gas volume in m³. 3 Where n is the number of moles of gas (mol), and R is the ideal gas constant, taken as 8.314 J·mol⁻¹. -1 ·k -1 ;

[0022] Gas concentration: The gas sensor provides the oxygen concentration value, which is calculated by comparing the concentration C with the monitored air volume V. monitorCalculate the volume V of the volatile gas;

[0023] ② Calculation of volatile matter:

[0024] The volume of volatile gas can be calculated using equation (2):

[0025] (2)

[0026] In the formula, C is the oxygen concentration, and V monitor The sensor can monitor volume;

[0027] Converting the gas volume to the liquid volume, the liquid-to-gas volume ratio of liquid oxygen is approximately 1:861, meaning that 1L of liquid oxygen can be volatilized into 861L of gaseous oxygen. The specific conversion is shown in equation (3):

[0028] (3)

[0029] ③ Pressure and temperature correction:

[0030] Based on the ideal gas law, the actual gas volume V r It can be corrected using equation (4):

[0031] (4)

[0032] In the formula, P std Standard atmospheric pressure, taken as 101325 Pa; T std The standard temperature is 25℃, and the thermodynamic temperature conversion here is 25 + 273.15 = 298.15 K; P real The actual liquid air pressure is expressed in Pa; T real The actual air temperature, in K;

[0033] ④ Calculation of evaporation rate:

[0034] By continuously monitoring the volume change data of the gas, the evaporation rate per unit time can be calculated, as shown in equation (5):

[0035] (5)

[0036] In the formula, R LOX Let ΔV be the evaporation rate of liquid air. LOX Δt represents the amount of liquid oxygen evaporated over a period of time;

[0037] Based on this, the total volatile amount V can be calculated over a certain period, from t1 to t2. A See equation (6):

[0038] (6).

[0039] In a preferred embodiment of this scheme, the method for calculating the amount of liquid air stored in the borehole in S4 is as follows:

[0040] The amount of liquid air injected by the flow meter, based on the amount of evaporation obtained in S3, can be used to accurately calculate the energy stored in the liquid air in the borehole, as shown in equation (7).

[0041] (7)

[0042] In the formula, V S V represents the amount of liquid air stored in the borehole. inlet V represents the amount of liquid air input into the pipeline. LOX Liquid air evaporation

[0043] Implementing the embodiments of the present invention has the following beneficial effects:

[0044] The precise filling liquid air energy storage rock breaking method of the present invention generates a detailed report on the injection and evaporation of liquid air by real-time data storage and processing, including evaporation rate, total evaporation, pressure and temperature changes, etc., so that on-site personnel can obtain the precise liquid air storage volume in the borehole in real time.

[0045] The technical solution of this invention is applicable to working conditions in industries such as water conservancy and hydropower, transportation, and mining where environmental protection, crushing effect, and degree of control are important, in order to improve the efficiency of liquid air energy storage rock breaking. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 Flowchart for precise filling of liquid air energy storage rock-breaking design;

[0048] Figure 2 This is a schematic diagram illustrating the change in pressure over time.

[0049] Figure 3 This is a schematic diagram of the sensor arrangement. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] Please see Figure 1 , Figure 1 A flowchart for the design of a precise liquid air energy storage rock-breaking system; this precise liquid air energy storage rock-breaking method specifically includes the following steps:

[0052] S1. A clamp-on ultrasonic flow meter is used to monitor the liquid air flow rate and update the injection volume in real time.

[0053] The specific steps are as follows: A clamp-on ultrasonic flow meter with non-contact measurement is used. It is placed outside the pipe by a clamp and uses sound wave conduction technology to measure the flow velocity of the fluid in the pipe, avoiding direct contact with the fluid.

[0054] S2. Use pressure sensors, oxygen concentration sensors, and temperature sensors to monitor liquid air leaks. Stop injection when the pipeline pressure, oxygen concentration in the air, and temperature are abnormal.

[0055] The specific steps are as follows: a pressure sensor is placed on the inner wall of the injection port, close to the borehole, to monitor the pressure change in the pipe when liquid air is injected into the borehole; an oxygen concentration sensor and a temperature sensor are installed on the outer wall of the pipeline injection port to ensure that the oxygen concentration and temperature are kept within a reasonable range during the liquid air injection process (reasonable oxygen concentration range 20.9%~22%vol, reasonable temperature range between -20°C and +40°C, depending on the specific geographical location and working conditions).

[0056] During the liquid oxygen energy storage rock breaking process, the abnormal behavior of pipeline pressure, ambient oxygen concentration, and temperature parameters is as follows:

[0057] 1. Abnormal Pipeline Pressure: A sudden drop in pressure (e.g., falling below 80% of normal operating pressure within a short period) usually indicates a serious leak in the pipeline or at a connection; while an abnormal increase in pressure (exceeding 120% of the system's rated operating pressure) may be caused by uncontrolled injection, pipeline blockage, or excessive liquid vaporization, posing a risk of physical explosion. (Normal operating pressure is not fixed, ranging from 1-3 MPa during low-pressure delivery and 5-20 MPa during high-pressure injection.)

[0058] 2. Abnormal oxygen concentration: If the oxygen concentration sensor reading continuously exceeds 23.5% (vol), it indicates that there is a leak of liquid oxygen or oxygen-enriched air and it has vaporized, creating a localized oxygen-enriched environment, which can easily lead to a catastrophic fire or explosion.

[0059] 3. Temperature anomalies: A sudden drop in local temperature (the temperature at a specific point drops sharply to -100°C or even lower) is a direct result of the leakage and vaporization of cryogenic liquids, which can lead to low-temperature brittleness of materials; conversely, an abnormal rise in temperature (greater than 60°C) may be due to an external heat source or insulation failure, which can accelerate the vaporization of liquids and become a dangerous ignition source in an oxygen-rich environment.

[0060] If any of the above parameters shows a significant abnormality, the system must immediately stop injection and activate the safety interlock procedure. The monitoring data for pressure, oxygen concentration, and temperature are often interconnected, forming a redundant safety protection system.

[0061] S3. By monitoring changes in oxygen concentration and using sensors, the volume of air can be measured, and the amount of liquid air evaporation can be calculated. Based on the ideal gas law, the volume of evaporating gas is corrected for pressure and temperature, and the evaporation rate is calculated.

[0062] The specific steps are as follows: Select an electrochemical sensor suitable for low temperature as the oxygen concentration sensor, and place it near the borehole, in a fan-shaped area with a radius of 1.5 meters to 5 meters centered on the borehole (downwind preferred). It is stably installed at a height of 0.3 to 0.5 meters above the ground to detect the concentration of volatile oxygen. Combined with gas volume, temperature, and pressure, the amount of volatile oxygen is accurately calculated.

[0063] Method for calculating volatile content:

[0064] Assuming the evaporated liquid air is an ideal gas, the calculation of the evaporation amount includes: ① measuring the gas volume and concentration; ② the amount of gas evaporation; ③ pressure and temperature corrections; ④ the evaporation rate.

[0065] ①Measure the volume and concentration of liquid air:

[0066] Oxygen volume: A gas sensor is used to monitor the volume of oxygen after the gas evaporates. Based on the ideal gas law, the changes in the gas state in the sensor's environment are analyzed.

[0067] The volume of the gas is calculated using the ideal gas law, as shown in equation (1):

[0068] (1)

[0069] In the formula: P is the gas pressure in Pa, and V is the gas volume in m³. 3 Where n is the number of moles of gas (mol), and R is the ideal gas constant, taken as 8.314 J·mol⁻¹. -1 ·k -1 ;

[0070] Gas concentration: The gas sensor provides the oxygen concentration value, which is calculated by comparing the concentration C with the monitored air volume V. monitorCalculate the volume V of the volatile gas;

[0071] ② Calculation of volatile matter:

[0072] The volume of volatile gas can be calculated using equation (2):

[0073] (2)

[0074] In the formula, C is the oxygen concentration, and V monitor The sensor can monitor volume;

[0075] Converting the gas volume to the liquid volume, the liquid-to-gas volume ratio of liquid oxygen is approximately 1:861, meaning that 1L of liquid oxygen can be volatilized into 861L of gaseous oxygen. The specific conversion is shown in equation (3):

[0076] (3)

[0077] ③ Pressure and temperature correction:

[0078] Based on the ideal gas law, the actual gas volume V r It can be corrected using equation (4):

[0079] (4)

[0080] In the formula, P std Standard atmospheric pressure, taken as 101325 Pa; T std The standard temperature is 25℃, and the thermodynamic temperature conversion here is 25 + 273.15 = 298.15 K; P real The actual liquid air pressure is expressed in Pa; T real The actual air temperature, in K;

[0081] ④ Calculation of evaporation rate:

[0082] By continuously monitoring the volume change data of the gas, the evaporation rate per unit time can be calculated, as shown in equation (5):

[0083] (5)

[0084] In the formula, R LOX Let ΔV be the evaporation rate of liquid air. LOX Δt represents the amount of liquid oxygen evaporated over a period of time;

[0085] Based on this, the total volatile amount V can be calculated over a certain period, from t1 to t2. A See equation (6):

[0086] (6).

[0087] S4. Based on the injection and evaporation rates of liquid air, accurately calculate the amount of liquid air stored in the borehole:

[0088] The amount of liquid air injected by the flow meter, based on the amount of evaporation obtained in S3, can be used to accurately calculate the energy stored in the liquid air in the borehole, as shown in equation (7).

[0089] (7)

[0090] In the formula, V S V represents the amount of liquid air stored in the borehole. inlet V represents the amount of liquid air input into the pipeline. LOX Liquid air evaporation

[0091] S5. Collect and summarize all sensor data in a unified manner at the control center, establish an embedded system to realize real-time data storage and processing, and generate detailed reports on the injection and evaporation of liquid air, including evaporation rate, total evaporation, pressure and temperature changes; when a sudden temperature change or abnormal pressure is detected, issue an alert and automatically shut down the transmission of liquid air. Specific Implementation

[0092] The excavation of a steep open-pit mine involves complex geological conditions and poor regional structural stability. The site has high requirements for environmental protection, fracturing effect and control. Liquid air fracturing blasting is adopted. This method only focuses on the precise filling of liquid air and does not consider the layout of blast holes, plugging, network connection and detonation.

[0093] This embodiment is performed according to the following steps:

[0094] (1) Liquid air injection measurement:

[0095] The device consists of two parts: a flow meter and temperature and pressure sensors. The flow meter is a clamp-on ultrasonic flow meter, which is placed outside the pipe by a clamp, without directly contacting the fluid and interfering with the fluid flow inside the pipe.

[0096] (2) Liquid air leakage monitoring

[0097] Monitoring is performed using a pressure sensor, with supplementary monitoring using an oxygen concentration sensor and a temperature sensor. The pressure sensor is located on the inner wall of the pipe inlet, while the oxygen concentration sensor and temperature sensor are located on the outer wall of the pipe inlet.

[0098] Multiple experiments were conducted to establish a model of pressure variation over time under normal engineering conditions, and a pressure threshold range was set. Figure 2This diagram illustrates the pressure change over time. The solid green line represents the pressure curve under normal conditions, where the pressure steadily increases and eventually remains constant as liquid air is injected. The solid red line represents the pressure curve under conditions of leakage through cracks, where liquid oxygen leaks through the cracks, preventing the normal accumulation of liquid oxygen in the orifice, reducing flow resistance, and causing the pressure inside the pipeline to drop.

[0099] Meanwhile, liquid oxygen leaks will rapidly absorb heat and evaporate. Temperature sensors and oxygen concentration sensors on the outer wall of the injection port are used as auxiliary monitoring methods. When a leak occurs, it will manifest as an abnormal drop in temperature or an abnormal increase in oxygen concentration.

[0100] (3) Monitoring of liquid air evaporation:

[0101] The electrochemical oxygen sensor monitors a space of 1m. 3 The sensor measured an increase in oxygen concentration from 21% to 25% over a period of 10 minutes. The calculations are as follows:

[0102] ①Volume of oxygen volatilization: ;

[0103] ② The volume of gas is converted into the volume of liquid air: That is, within 10 minutes, 46.5 mL of liquid air evaporated into gas.

[0104] ③ Evaporation rate: .

[0105] (4) Precision filling liquid air energy storage design method:

[0106] See the schematic diagram of the sensor installation layout. Figure 3 All sensor data is collected and aggregated at the control center. An embedded system is established through a computer to store and process the data in real time, generating detailed reports on the injection and evaporation of liquid air, including evaporation rate, total evaporation, pressure and temperature changes, etc. When a sudden temperature change or abnormal pressure is detected, an alert is issued and the liquid air transmission is automatically shut off.

[0107] This invention, based on the volatility of liquid air at room temperature, corrects for vaporization losses from the perspectives of pressure and temperature during liquid air filling, proposing a precise liquid air energy storage rock-breaking technology. First, a clamp-on ultrasonic flow meter is used to update the liquid air injection volume in real time. Then, liquid air leakage monitoring is implemented. Considering the possibility of cracks in the borehole wall causing liquid air loss, pressure, temperature, and oxygen concentration sensors are installed for monitoring. Abnormal changes in pressure, temperature near the borehole opening, or oxygen concentration can be used as potential signals of crack leakage, interrupting liquid air injection into that borehole. The amount of liquid air evaporation can be calculated from changes in oxygen concentration. Pressure and temperature corrections are applied to the evaporation amount, and the liquid air energy stored in the borehole is the difference between the injection and evaporation amounts. Finally, all sensor data is collected and aggregated at a control center, establishing an embedded system to achieve real-time data storage and processing, generating detailed reports on the injection and evaporation amounts of liquid air, including evaporation rate, total evaporation, pressure and temperature changes, etc. On-site personnel can obtain accurate real-time data on the amount of liquid air stored in the borehole. This invention can be used in industries such as water conservancy and hydropower, transportation, and mining where environmental protection, crushing effect, and degree of control are important, in order to improve the efficiency of liquid air energy storage rock breaking.

[0108] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for precisely filling liquid air energy storage for rock breaking, characterized in that, Includes the following steps: S1. A clamp-on ultrasonic flow meter is used to monitor the liquid air flow rate and update the injection volume in real time. S2. Use pressure sensors, oxygen concentration sensors, and temperature sensors to monitor liquid air leaks. Stop injection when the pipeline pressure, oxygen concentration in the air, and temperature are abnormal. S3. By monitoring changes in oxygen concentration and using sensors, the volume of air can be measured, and the amount of liquid air evaporation can be calculated. Based on the ideal gas law, the volume of evaporating gas is corrected for pressure and temperature, and the evaporation rate is calculated. S4. Based on the amount of liquid air injected and evaporated, accurately calculate the amount of liquid air stored in the borehole; S5. Collect and summarize all sensor data in a unified manner at the control center, establish an embedded system to realize real-time data storage and processing, and generate detailed reports on the injection and evaporation of liquid air, including evaporation rate, total evaporation, pressure and temperature changes; when a sudden temperature change or abnormal pressure is detected, issue an alert and automatically shut down the transmission of liquid air.

2. The method for precisely filling liquid air energy storage rock breaking according to claim 1, characterized in that, The specific steps of S1 are as follows: a clamp-on ultrasonic flow meter with non-contact measurement is used, which is placed outside the pipe by a clamp and uses sound wave conduction technology to measure the flow velocity of the fluid in the pipe, avoiding direct contact with the fluid.

3. The method for precisely filling liquid air energy storage rock breaking according to claim 1, characterized in that, The specific steps of S2 are as follows: a pressure sensor is arranged on the inner wall of the injection port, close to the borehole, to monitor the pressure change in the pipe when liquid air is injected into the borehole; an oxygen concentration sensor and a temperature sensor are installed on the outer wall of the pipe injection port to ensure that the oxygen concentration and temperature are kept within a reasonable range during the liquid air injection process.

4. The method for precisely filling liquid air energy storage rock-breaking as described in claim 1, characterized in that, The specific steps of S3 are as follows: Select an electrochemical sensor suitable for low temperature as an oxygen concentration sensor, place it near the borehole, and use it to detect the concentration of volatilized oxygen. Combine the gas volume, temperature, and pressure to accurately calculate the amount of volatilization.

5. The method for precisely filling liquid air energy storage rock breaking according to claim 4, characterized in that, Method for calculating volatile content: Assuming the evaporated liquid air is an ideal gas, the calculation of the evaporation amount includes: ① measuring the gas volume and concentration; ② the amount of gas evaporation; ③ pressure and temperature corrections; ④ the evaporation rate. ①Measure the volume and concentration of liquid air: Oxygen volume: A gas sensor is used to monitor the volume of oxygen after the gas evaporates. Based on the ideal gas law, the changes in the gas state in the sensor's environment are analyzed. The volume of the gas is calculated using the ideal gas law, as shown in equation (1): （1） In the formula: P is the gas pressure in Pa, and V is the gas volume in m³. 3 Where n is the number of moles of gas (mol), and R is the ideal gas constant, taken as 8.314 J·mol⁻¹. -1 ·k -1 ; Gas concentration: The gas sensor provides the oxygen concentration value, which is calculated by comparing the concentration C with the monitored air volume V. monitor Calculate the volume V of the volatile gas; ② Calculation of volatile matter: The volume of volatile gas can be calculated using equation (2): （2） In the formula, C is the oxygen concentration, and V monitor The sensor can monitor volume; Converting the gas volume to the liquid volume, the liquid-to-gas volume ratio of liquid oxygen is approximately 1:861, meaning that 1L of liquid oxygen can be volatilized into 861L of gaseous oxygen. The specific conversion is shown in equation (3): （3） ③ Pressure and temperature correction: Based on the ideal gas law, the actual gas volume V r It can be corrected using equation (4): （4） In the formula, P std Standard atmospheric pressure, taken as 101325 Pa; T std The standard temperature is 25℃, and the thermodynamic temperature conversion here is 25 + 273.15 = 298.15 K; P real The actual liquid air pressure is expressed in Pa; T real The actual air temperature, in K; ④ Calculation of evaporation rate: By continuously monitoring the volume change data of the gas, the evaporation rate per unit time can be calculated, as shown in equation (5): （5） In the formula, R LOX Let ΔV be the evaporation rate of liquid air. LOX Δt represents the amount of liquid oxygen evaporated over a period of time; Based on this, the total volatile amount V can be calculated over a certain period, from t1 to t2. A See equation (6): （6）。 6. The method for precisely filling liquid air energy storage rock breaking according to claim 1, characterized in that, The method for calculating the amount of liquid air stored in the borehole in S4 is as follows: The amount of liquid air injected by the flow meter, based on the amount of evaporation obtained in S3, can be used to accurately calculate the energy stored in the liquid air in the borehole, as shown in equation (7). （7） In the formula, V S V represents the amount of liquid air stored in the borehole. inlet V represents the amount of liquid air input into the pipeline. LOX This represents the amount of liquid air that evaporates.

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