Method for detecting calorific value of low-calorific-value sludge

Abstract

The invention relates to a calorific value detection method for low-calorific-value sludge, which comprises the following steps: (1) weighing a sludge sample to be detected and mixing with a coal sample to obtain a detection sample; and (2) determining the total calorific value of the detection sample, and subtracting the calorific value of the coal sample to obtain the calorific value of the detected sludge sample. Compared with the prior art, the method has the advantages that the calorific value of the mixed sample can be matched with the detection range of the calorimeter under the condition that equipment is not updated by adding the standard coal substance, so that the accuracy of a sludge calorific value detection result is greatly improved.

Description

Technical Field

[0001] The invention belongs to the technical field of calorific value detection methods and relates to a calorific value detection method for low calorific value sludge. Background Art

[0002] At present, there is no clear provision in the national standard on the detection method of sludge calorific value. It is generally tested according to the fuel calorific value detection method specified in GB_T30727-2014.

[0003] However, since the calorific value range of sludge is very low, the temperature rise range during the test cannot reach the effective working range of the calorimeter commonly used in the laboratory, resulting in situations where detection cannot be performed or the detection data has large errors.

[0004] Moreover, since the sludge itself has a high ash content and is not easy to burn, the commonly used calorific value detection method will often result in the sludge sample not being able to burn out, and there will be large differences in the data during parallel samples and repeated tests.

[0005] Due to the above problems, when using the original detection method, the validity and accuracy of the data are poor, the sample utilization rate and detection efficiency are extremely low, some test data are unqualified or even unusable, and repeated testing is required, resulting in waste of manpower costs and loss of equipment and consumables, as well as delays in detection time. Summary of the invention

[0006] The purpose of the present invention is to provide a calorific value detection method for low calorific value sludge. By adding standard coal material, the ignition success rate of the sludge sample is improved without updating the equipment, so that the calorific value of the mixed sample can match the detection range of the calorimeter, thereby greatly improving the accuracy of the sludge calorific value detection results.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] A method for detecting the calorific value of low calorific value sludge comprises the following steps:

[0009] (1) Weighing a sludge sample to be tested and mixing it with a coal sample to obtain a test sample;

[0010] (2) Determine the total calorific value of the test sample and then subtract the calorific value of the coal sample to obtain the calorific value of the sludge sample being tested.

[0011] Furthermore, the coal sample is standard coal.

[0012] Furthermore, the amount of the coal sample added satisfies that: the temperature rise generated by the heat released by the obtained test sample during combustion reaches the effective detection range of the calorimeter.

[0013] Furthermore, the mass ratio of the added amount of the tested sludge sample to the coal sample is (0.8-1.2):(0.45-0.55).

[0014] Furthermore, the mass ratio of the added amount of the tested sludge sample to the coal sample is 1:(0.45-0.55).

[0015] Furthermore, the method for determining the total calorific value of the test sample is carried out in accordance with the provisions of GB_T 30727-2014.

[0016] Furthermore, the method and process for determining the gross calorific value of the test sample is consistent with the calorific value of the coal sample.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] (1) By adding standard coal material, the calorific value of the mixed sample can be matched with the detection range of the calorimeter without updating the equipment, which greatly improves the accuracy of the sludge calorific value detection results.

[0019] (2) The ignition success rate is improved, and the calorific value of the sample after successful ignition reaches the detection limit of the calorific value analyzer, thereby improving the overall experimental success rate of the calorific value test of low calorific value sludge samples.

[0020] (3) Reduce the number of ignition failures, improve detection efficiency and sample utilization, and reduce personnel workload.

[0021] (4) The gas generated during the sludge detection process is corrosive. Reducing the number of detections increases the service life of the oxygen bomb and reduces the depreciation rate of the equipment.

[0022] (5) It has a wide range of applications. Enterprises that need to carry out sludge blending combustion can use this method to detect the sludge calorific value. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The figure is a comparison chart of the qualified rate of sludge calorific value detection between the existing scheme and the detection method of the present invention. DETAILED DESCRIPTION

[0024] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0025] In the following examples, unless otherwise specified, raw materials or processing techniques are conventional commercially available raw materials or conventional processing techniques in the art.

[0026] In order to realize the calorific value detection of low calorific value sludge samples that cannot be identified by thermal value or the temperature rise generated by the heat released by combustion cannot reach the effective detection range of heat immediately, the present invention provides a calorific value detection method for low calorific value sludge, comprising the following steps:

[0027] (1) Weighing a sludge sample to be tested and mixing it with a coal sample to obtain a test sample;

[0028] (2) Determine the total calorific value of the test sample and then subtract the calorific value of the coal sample to obtain the calorific value of the sludge sample being tested.

[0029] The detection working principle process of the present invention is:

[0030] Adding an appropriate amount of standard coal to the low calorific value sludge sample increases the total calorific value of the sample. The heat released by the combustion of the sample during the test causes the temperature rise of the inner cylinder to reach the effective detection range of the calorimeter, thereby obtaining accurate test results. In this way, after adding the standard coal, the combustion time of the sludge sample is increased, the probability of ignition failure is greatly reduced, the sludge sample can be fully burned, and the consistency of the test results is better. Then, the calorific value of the cylinder (total calorific value) obtained by the calorimeter is subtracted from the added heat generated by the standard coal to obtain the calorific value of the sludge.

[0031] In some specific embodiments, the coal sample is standard coal.

[0032] In some specific embodiments, the amount of the coal sample added satisfies that: the temperature rise generated by the heat released by the obtained test sample during combustion reaches the effective detection range of the calorimeter.

[0033] In some specific implementations, the mass ratio of the added amount of the sludge sample to be tested to the coal sample is (0.8-1.2): (0.45-0.55).

[0034] In a more specific implementation manner, the mass ratio of the added amount of the sludge sample to be tested to the coal sample is 1:(0.45-0.55).

[0035] In some specific embodiments, the method for determining the total calorific value of the test sample is carried out in accordance with the provisions of GB_T 30727-2014.

[0036] In some specific embodiments, the method and process for determining the total calorific value of the test sample is consistent with the calorific value of the coal sample.

[0037] The above embodiments may be implemented individually or in any combination of two or more.

[0038] The above implementation is described in more detail below in conjunction with specific examples.

[0039] Embodiment 1:

[0040] A method for detecting the calorific value of low calorific value sludge comprises the following steps:

[0041] (1) Weigh 1 g of the sludge sample to be tested and mix it with 0.5 g of the standard coal sample to obtain a test sample;

[0042] (2) Determine the total calorific value of the test sample according to the provisions of GB_T 30727-2014, and then subtract the calorific value of the standard coal sample to obtain the calorific value of the sludge sample being tested.

[0043] The qualified rate obtained by directly measuring the calorific value of the sludge sample under test according to the provisions of GB_T 30727-2014 is compared, such as Figure 1 As shown ( Figure 1 The vertical axis is the detection qualified rate, and the horizontal axis is the detection time period). A sludge sample is tested twice as a group. Each group of data meets the calorific value data judgment standard (i.e. GB_T 30727-2014, solid biomass fuel calorific value determination method) and is qualified. It can be seen that after adopting the scheme of the present invention, the detection qualified rate of sludge calorific value is greatly improved, which can effectively reduce the number of tests and improve the detection efficiency and accuracy.

[0044] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A method for detecting the calorific value of low calorific value sludge, characterized in that: The following steps are involved: (1) Weighing a sludge sample to be tested and mixing it with a coal sample to obtain a test sample; (2) Determine the total calorific value of the test sample and then subtract the calorific value of the coal sample to obtain the calorific value of the sludge sample being tested.

2. A calorific value detection method for low calorific value sludge according to claim 1, characterized in that: The coal sample is standard coal.

3. A calorific value detection method for low calorific value sludge according to claim 1, characterized in that: The amount of the coal sample added is such that the temperature rise generated by the heat released by the obtained test sample during combustion reaches the effective detection range of the calorimeter.

4. A calorific value detection method for low calorific value sludge according to claim 1, characterized in that: The mass ratio of the added amount of the tested sludge sample to the coal sample is (0.8-1.2):(0.45-0.55).

5. A calorific value detection method for low calorific value sludge according to claim 4, characterized in that: The mass ratio of the added amount of the tested sludge sample to the coal sample is 1:(0.45-0.55).

6. A calorific value detection method for low calorific value sludge according to claim 4, characterized in that: The mass ratio of the added amount of the tested sludge sample to the coal sample is 1:0.

5.

7. A calorific value detection method for low calorific value sludge according to claim 1, characterized in that: The method for determining the total calorific value of the test sample shall be carried out in accordance with the provisions of GB_T 30727-2014.

8. A method for detecting the calorific value of low calorific value sludge according to claim 1, characterized in that: The method and process for determining the gross calorific value of the test sample is consistent with the calorific value of the coal sample.

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