Landfill fly ash weight estimation method

Abstract

The invention discloses a landfill fly ash weight estimation method, which relates to the technical field of mass estimation, and realizes the estimation of the natural weight increment of landfill fly ash by analyzing the moisture content, ignition loss and bulk density of fly ash, determining the content of chemically stable components in fly ash and solving the total mass by using stable and invariable components. Comprising water content detection, ignition loss detection and stacking density detection, the water content detection is used for detecting the water content in the fly ash, the ignition loss detection is used for detecting the percentage of the lost mass of a sample in the mass of an original sample after the fly ash is burnt at a high temperature, and the stacking density detection is used for detecting the stacking density of the fly ash. According to the landfill fly ash weight estimation method, a plurality of key indexes such as the moisture content, the ignition loss and the residue value are introduced for characteristic analysis. And the mass of components which are kept stable and unchanged in the weight increasing process in the fly ash can be accurately measured. Based on the data, the overall weight of the fly ash in the current stage can be calculated.

Description

Technical Field

[0001] The invention relates to the technical field of mass estimation, in particular to a method for estimating the weight of landfill fly ash. Background Art

[0002] Fly ash usually refers to fine solid particles produced during the incineration of domestic waste, accounting for about 3% to 5% of the incineration disposal volume. The main hazardous components include heavy metals, dioxins, etc. According to relevant regulations, during the storage and transportation of fly ash, it should be sealed and placed in sealed containers, or transported in bulk using sealed tank trucks. As a hazardous waste, fly ash from the incineration of domestic waste needs to be landfilled in a rigid landfill for harmless disposal.

[0003] In the fly ash disposal process where landfill is the main treatment method, polypropylene fiber textile ton bags are used as a common closed packaging form. However, during the pretreatment stage of the landfill pit or the long-term compressing process after landfill, the fly ash will face an environment with long-term and extensive contact with the air. At this time, the natural weight gain effect of the fly ash must be considered. For fly ash that has been landfilled, its natural weight gain effect may cause the weight of the fly ash to be inconsistent with the records of hazardous waste transfer ledgers when the fly ash is excavated and recycled in a rigid landfill. Therefore, before the excavation operation, the weight of the fly ash in the landfill must be reasonably estimated and reported to the ecological and environmental authorities to obtain an environmental impact assessment, and arrange the engineering volume and plan related work accordingly.

[0004] The existing fly ash weight estimation refers to the method of estimating the weight by sampling earthwork transportation. Due to the huge difference in bulk density or stacking density of fly ash on the surface and bottom layers of the fly ash landfill, the common density of new ash is 0.45g / cm3, and the squeezed fly ash in the middle and bottom of the landfill can reach 0.95g / cm3. If the earthwork weight is converted using statistical methods alone, the weight estimation will vary greatly and is not of reference value. Therefore, a method for estimating the weight of landfill fly ash is proposed. Summary of the invention

[0005] The object of the present invention is to provide a method for estimating the weight of landfill fly ash to solve the problem of inaccurate mass estimation in the prior art.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a method for estimating the weight of landfill fly ash, which determines the content of chemically stable components in the fly ash by analyzing the moisture content, loss on ignition and bulk density of the fly ash, and calculates the total mass with the stable and unchanging components to realize the estimation of the natural weight gain of the fly ash in the landfill. The method includes three main parts: moisture content detection, loss on ignition detection and bulk density detection. First, moisture content detection is used to accurately determine the moisture content in the fly ash sample. Secondly, loss on ignition detection is to burn the fly ash sample in a high temperature environment, measure the percentage of the mass lost by the sample during the burning process to the original sample mass, thereby evaluating the loss on ignition of the fly ash. Finally, bulk density detection focuses on the density of the fly ash in a stacked state. Through these three detection steps, the physical and chemical properties of the fly ash can be fully understood, providing a scientific basis for the resource utilization and environmental management of the fly ash.

[0007] Preferably, the moisture content refers to the percentage of the mass of water in the solid waste in the fly ash to the total mass of the solid waste. When measuring, a sample with a mass of m is placed in an electric drying oven for drying, the temperature is controlled at 105°C, the sample is dried for 2 hours, cooled to room temperature in a dryer, and weighed to obtain a mass m. s , the moisture content is calculated as

[0008] Preferably, the loss on ignition refers to the percentage of the mass lost by the sample after high-temperature calcination to the mass of the original sample. During measurement, a sample with a mass of m is placed in a high-temperature muffle furnace and gradually heated to 950°C and calcined for 20 minutes. The total mass of the sample and the crucible is recorded as m0, and the total mass of the sample crucible after high-temperature combustion is recorded as m1. The calculated loss on ignition is recorded as LOI.

[0009] Preferably, the sample with a mass of m is placed in a high-temperature muffle furnace and gradually heated to 950°C to obtain a residue, the mass of the residue is D, and the relationship between the components of the incineration fly ash is: total mass A-water weight B-burnt weight C=residue D. At this stage, the weight A of landfill fly ash can be understood as A=B+C+D.

[0010] Preferably, the bulk density refers to the mass per unit volume of the fly ash granular material in a stacked state.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] 1. This application analyzes and utilizes the existing landfill record data of the landfill, combined with in-depth research on the measurable indicators of the already filled fly ash, such as moisture content, loss on ignition and other key parameters, to conduct weight gain characteristic test analysis on the newly generated fly ash at the waste production end. Through these tests, the aim is to determine the specific content of chemically stable components in the fly ash. On this basis, the total mass of the fly ash can be obtained by calculating the stable and unchanging components. Ultimately, this series of analyses and calculations will help us achieve a preliminary estimate of the natural weight gain of fly ash in the landfill, thereby providing a scientific basis for the management and planning of the landfill.

[0013] 2. Compared with the traditional statistical estimation method, the present application proposes a more sophisticated and in-depth analysis method, focusing on the physical and chemical principles in the fly ash weight gain process. In this process, not only the basic characteristics of fly ash weight gain are considered, but also multiple key indicators such as moisture content, loss on ignition, and residue value are specially introduced for characteristic analysis. Through a series of carefully designed experiments, the mass of those components in fly ash that remain stable during the weight gain process can be accurately determined. Based on these data, we can then calculate the overall weight of the fly ash at the current stage, thereby providing a more accurate and reliable reference basis for research and application in related fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a flow chart of fly ash mass estimation in the present invention;

[0015] Figure 2 The fly ash weight in the present invention changes with the observation time curve

[0016] Figure 3 It is a curve diagram of the change of fly ash moisture content and ignition loss with observation time in the present invention;

[0017] Figure 4 It is a curve diagram of the fly ash residue changing with the observation time in the present invention;

[0018] Figure 5 It is a curve diagram showing the variation of the residual weight of unit fly ash after burning versus observation time in the present invention. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only a part of many possible embodiments of the present invention, not all embodiments. Based on these specific embodiments of the present invention, all other possible embodiments that can be understood and derived by ordinary technicians in this field without any creative work and extra efforts should also be regarded as within the scope of protection of the present invention.

[0020] like Figure 1, Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, the present invention provides a technical solution for a method for estimating the weight of landfill fly ash, including moisture content detection, ignition loss detection and bulk density detection. The moisture content detection is used to detect the moisture content in the fly ash. The ignition loss detection is used to detect the percentage of the mass lost by the sample after high-temperature calcination of the fly ash to the mass of the original sample. The bulk density detection is used to detect the density of the fly ash accumulation.

[0021] Specifically, moisture content refers to the ratio between the mass of water in the solid waste in the fly ash and the total mass of the solid waste, expressed as a percentage. In order to measure the moisture content, you first need to prepare a sample with a mass of m. The sample will then be placed in an electric drying oven for drying. During this process, the temperature needs to be strictly controlled at 105°C. After the sample is dried at this temperature for two hours, it needs to be transferred to a dryer and allowed to cool naturally to room temperature. After cooling is completed, the sample is weighed again, and the mass obtained is recorded as m s Through a series of calculations, we can get the moisture content, using On the other hand, loss on ignition refers to the ratio of the mass lost by a sample during high-temperature calcination to the mass of the original sample, also expressed as a percentage. To measure the loss on ignition, a sample of mass m is placed in a high-temperature muffle furnace. In the furnace, the sample is gradually heated to 950°C and burned at this temperature for 20 minutes. Before burning, the total mass of the sample and the crucible needs to be recorded, recorded as m0. After high-temperature combustion, the total mass of the sample and the crucible needs to be recorded again, recorded as m1. By calculating the difference between m0 and m1, we can get the loss on ignition, expressed as LOI.

[0022] During the experiment, a sample with a mass of m was first taken, and then the sample was placed in a high-temperature muffle furnace for treatment. By gradually increasing the temperature, we finally heated the sample to 950℃ and burned it at high temperature. After this series of treatments, we obtained the residue part of the sample, whose mass we use D to represent. Analysis of the relationship between the components of the incineration fly ash shows that the total mass A minus the weight B of the water contained in the sample, and then minus the weight C of the sample burned during the burning process, and the final difference is the mass D of the residue. Therefore, at this stage, for the weight A of landfill fly ash, we can understand that it is composed of three parts: the weight B of water, the weight C of loss on burning, and the mass D of the residue. By introducing characteristic analysis of indicators such as moisture content, loss on burning, and residue value into the weight gain characteristics of fly ash, we can have a deeper understanding of the physical and chemical properties of fly ash. Through a series of carefully designed experimental processes, we were able to measure and analyze the mass of stable and unchanging components in fly ash. The mass of these components is a key factor in evaluating the overall weight change of fly ash. Based on these data, we can calculate the overall weight of fly ash at the current stage.

[0023] When making an estimate, it is first necessary to make an estimate based on the actual size of the landfill and the weight of the fly ash that has been landfilled. The entire landfill is divided into several specific sub-areas using the chessboard method. Within these sub-areas, further point distribution and sampling work are carried out. For each sample obtained, it will be numbered, and the corresponding waste-producing customer information of the sample will be recorded at the same time. Under normal circumstances, the batch of solid waste processed will not be less than 10,000 tons, and the number of samples is set to 80. Next, these sampled samples are subjected to a series of tests, mainly including the determination of moisture content (W) and loss on ignition (LOI). After completing these initial tests, the samples are placed under natural conditions for weight gain tests. The duration of the test is set to 30 days. During this period, the moisture content and loss on ignition of the test samples need to be regularly tested, and the results of each test need to be recorded in detail. From these data, the residual weight of the test sample can be calculated. Finally, based on the relationship between the sample and the total amount, the D value of the fly ash loss on ignition residue of each customer is calculated and found. Calculate the fly ash moisture weight according to the fly ash moisture content W, loss on ignition LOI, and the residue D value obtained in S2 Loss on ignition According to the formula ABC=D, we can know that A[1-W-(1-W)*LOI]=D, A=D / [1-W-(1-W)*LOI], and finally according to A=D / [1-W-(1-W)*LOI], when calculating the fly ash weight of the landfill at the current stage, it is necessary to divide the fly ash into different areas and estimate the landfill weight of each area. In this process, if the landfill weight of fly ash in a certain area accounts for less than 1%, it can be considered that the increase in fly ash weight in this area has little impact on the overall calculation result, so it can be ignored. For these extremely small increases in fly ash weight, we can directly use the landfill volume data recorded on the books without additional measurement or estimation.

[0024] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention should be defined by the appended claims, rather than just by the above detailed description. Therefore, it is intended that the present invention include all possible variations that fall within the meaning and scope of the equivalent elements defined in the claims. When interpreting and implementing the present invention, any figure mark appearing in the claims should not be regarded as a limitation of the claims involved.

Claims

1. A method for estimating the weight of landfill fly ash, characterized in that: By analyzing the moisture content, loss on ignition and bulk density of fly ash, the content of chemically stable components in the fly ash is determined, and the total mass is calculated based on the stable and unchanging components, so as to estimate the natural weight gain of fly ash in the landfill. The method includes moisture content detection, loss on ignition detection and bulk density detection. The moisture content detection is used to detect the moisture content in the fly ash. The loss on ignition detection is used to detect the percentage of the mass lost by the sample after high-temperature calcination of the fly ash to the mass of the original sample. The bulk density detection is used to detect the density of the fly ash accumulation.

2. A method for estimating the weight of landfill fly ash according to claim 1, characterized in that: The moisture content refers to the percentage of the mass of water in the solid waste in the fly ash to the total mass of the solid waste. When measuring, a sample with a mass of m is placed in an electric drying oven for drying. The temperature is controlled at 105°C. The sample is dried for 2 hours, cooled to room temperature in the dryer, and weighed to obtain the mass m. s , the moisture content is calculated as The specific calculation formula for moisture content is:

3. A method for estimating the weight of landfill fly ash according to claim 2, characterized in that: The loss on ignition refers to the percentage of the mass lost by the sample after high-temperature calcination to the mass of the original sample. During the measurement, a sample with a mass of m is placed in a high-temperature muffle furnace and gradually heated to 950°C and calcined for 20 minutes. The total mass of the sample and the crucible is recorded as m0, and the total mass of the sample crucible after high-temperature combustion is recorded as m1. The calculated loss on ignition is recorded as LOI. The specific calculation formula for the loss on ignition is:

4. A method for estimating the weight of landfill fly ash according to claim 3, characterized in that: The sample with a mass of m is placed in a high-temperature muffle furnace and gradually heated to 950°C to burn to obtain a residue. The mass of the residue is D. The relationship between the components of the incineration fly ash is: total mass A-water weight B-burnt weight C=residue D. At this stage, the weight of landfill fly ash A can be understood as A=B+C+D.

5. A method for estimating the weight of landfill fly ash according to claim 4, characterized in that: The bulk density refers to the mass per unit volume of fly ash granular material in a bulk state.

6. A method for estimating the weight of landfill fly ash according to claim 5, characterized in that: The estimation steps are as follows: S1: Based on the size of the landfill and the weight of the fly ash already filled, the landfill is divided into corresponding sub-areas using the chessboard point distribution method, and points and samples are distributed in the area. The sample number also records the corresponding waste-producing end customer when the sub-area landfill is divided. The common solid waste batch is ≥10,000t, with 80 copies. The moisture content W and loss on ignition LOI of the sampled samples are tested; S2: Take samples of newly generated fly ash from the waste-producing customers involved in the sampling in S1, conduct a weight gain test under natural conditions, and observe for 30 days. Regularity detection and record the moisture content W and loss on ignition LOI indicators of the test samples, calculate the residue weight of the test samples, and calculate the D value of the fly ash loss on ignition residue of each customer based on the relationship between the sample and the total amount; S3: Calculate the fly ash moisture weight based on the sampled fly ash moisture content W, loss on ignition LOI, and the residue D value obtained in S2 Loss on ignition According to the formula ABC=D, we can know that A[1-W-(1-W)*LOI]=D, A=D / [1-W-(1-W)*LOI]; S4: Calculate the current fly ash weight of the landfill based on A=D / [1-W-(1-W)*LOI]. When estimating, if the fly ash landfill weight accounts for less than 1% of the landfill weight of each partition, the added fly ash weight of customers can be ignored, and the landfill volume can be directly recorded in the books.

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