Method for promoting hydrogen production through sludge and endocrine disrupter-pyrolysis coupling system

Abstract

The invention relates to a method for producing hydrogen through co-pyrolysis of sludge and endocrine disrupter, and belongs to the technical field of solid waste recycling. In order to solve the problems of low anaerobic fermentation hydrogen production efficiency, long period and great environmental harm caused by endocrine disruptors in the prior art, the method comprises the following steps: step 1, screening, concentrating and drying sludge to obtain a dried sludge sample, step 2, setting and adding 2, 6-DCP sludge with the content of 10%, 20% and 30%, and step 3, adding 2, 6-DCP into the dried sludge sample, and constructing and operating an endocrine disrupter and sludge co-pyrolysis hydrogen production system. According to the invention, a rapid pyrolysis method and an electric heating mode are adopted, the temperature is rapidly raised to the target temperature, and then the sludge is pyrolyzed, so that the time and the economic cost of the pyrolysis process are reduced, and the efficiency of sludge treatment is realized.

Description

Technical Field

[0001] The invention relates to a method for producing hydrogen by co-pyrolysis of sludge and endocrine disruptors, belonging to the technical field of solid waste resource utilization. Background Art

[0002] With the rapid development of the economy and society, people's daily life, industrial production and many other factors have caused a large amount of hazardous waste such as sewage and sludge to be discharged. At present, sludge treatment technologies are mainly concentrated, dehydrated, digested, pyrolyzed and dried. Among them, sludge pyrolysis technology is favored due to its dual advantages of solid waste recycling and effective energy recovery. The production of high-value products such as biochar, oil, and gas through sludge pyrolysis can not only solve the problem of sludge environmental pollution, achieve sludge reduction and harmlessness, but also realize the recycling of sludge resources. Therefore, sludge pyrolysis, as a processing technology and recycling technology for recovering resources in sludge, will become the development trend of sludge treatment and disposal technology in the future.

[0003] Sludge pyrolysis technology has high energy consumption and large investment due to its high temperature, which is not advantageous compared with other treatment methods. Therefore, how to reduce costs will become the key to the large-scale application of pyrolysis technology in the future.

[0004] Therefore, it is urgent to propose a method for producing hydrogen by co-pyrolysis of sludge and endocrine disruptors to solve the above technical problems. Summary of the invention

[0005] The purpose of the present invention is to solve the problems of low efficiency and long cycle of anaerobic fermentation hydrogen production formed by common technology, as well as the great environmental harm of endocrine disruptors. A brief overview of the present invention is given below to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to determine the key or important parts of the present invention, nor is it intended to limit the scope of the present invention.

[0006] The technical solution of the present invention:

[0007] A method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system, comprising the following steps:

[0008] Step 1: Place the dehydrated sludge after plate and frame filter pressing in an oven for drying, grind the sludge in a grinder and sieve it to obtain dry sludge powder;

[0009] Step 2: adding 2,6-DCP to the dry sludge powder, and moving the mixture to a constant temperature rotary oscillator to uniformly mix the 2,6-DCP in the dry sludge powder, wherein the content of 2,6-DCP in the dry sludge powder is 10%-30%;

[0010] Step 3: put the evenly mixed dry sludge powder into a quartz boat, place it at the left end of the quartz tube in the tube furnace, and pass high-purity nitrogen into the quartz tube;

[0011] Step 4: Heat up the tubular furnace, and after heating up, push the quartz boat containing the dry sludge powder into the center of the furnace chamber to start pyrolysis, generating hydrogen-rich gas.

[0012] Preferably: the oven temperature is 105°C and the drying time is 24h.

[0013] Preferably, the content of 2,6-DCP in the dried sludge powder is 10%, 20%, or 30%.

[0014] Preferably, the temperature of the constant temperature rotary oscillator is 50° C., the rotation speed is 200 rpm, and the rotation time is 0.5 h.

[0015] Preferably, high-purity nitrogen is ventilated at a flow rate of 100 mL / min for 30 min.

[0016] Preferably, the temperature in the tube furnace is raised to 800° C. at a heating rate of 10° C. / min.

[0017] Preferably, the pyrolysis duration is 30 min.

[0018] The present invention has the following beneficial effects:

[0019] The present invention adopts a rapid pyrolysis method and an electric heating method to rapidly heat the temperature to the target temperature before pyrolyzing the sludge, thereby reducing the time and economic cost of the pyrolysis process and achieving efficient sludge treatment.

[0020] The present invention co-pyrolyzes endocrine disruptors with sludge, thereby, on the one hand, solving the pollution problem caused by the presence of endocrine disruptors in sludge, and on the other hand, utilizing the effect of endocrine disruptors on sludge to promote hydrogen production in sludge, thereby achieving stabilization, harmlessness and resource utilization of sludge treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is the ratio of biochar, bio-oil and gas obtained after rapid pyrolysis of sludge and endocrine disruptors;

[0022] Figure 2 It is the proportion of each component of pyrolysis gas. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is described below by the specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0024] Specific implementation method 1: Combination Figure 1-Figure 2 This embodiment is described. A method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system in this embodiment includes the following steps:

[0025] Step 1: Place the dehydrated sludge after plate and frame filter pressing in an oven for drying, grind the sludge in a grinder and sieve it to obtain dry sludge powder;

[0026] Step 2: adding 2,6-DCP to the dry sludge powder, and moving the mixture to a constant temperature rotary oscillator to uniformly mix the 2,6-DCP in the dry sludge powder, wherein the content of 2,6-DCP in the dry sludge powder is 10%-30%;

[0027] Step 3: put the evenly mixed dry sludge powder into a quartz boat, place it at the left end of the quartz tube in the tube furnace, and pass high-purity nitrogen into the quartz tube;

[0028] Step 4: Heat up the tubular furnace, and after heating up, push the quartz boat containing the dry sludge powder into the center of the furnace chamber to start pyrolysis, generating hydrogen-rich gas.

[0029] Specific implementation method 2: Combination Figure 1-Figure 2 The present embodiment is described as a method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system, wherein the oven temperature is 105° C. and the drying time is 24 hours to effectively remove most of the moisture in the sludge.

[0030] Specific implementation method three: Combination Figure 1-Figure 2 The present embodiment is described as a method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system. The temperature of the constant temperature rotary oscillator is 50°C, the rotation speed is 200rpm, and the rotation time is 0.5h to ensure the accuracy and repeatability of the experimental results.

[0031] Specific implementation method four: Combination Figure 1-Figure 2 The present embodiment is described as a method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system. High-purity nitrogen is ventilated at a flow rate of 100 mL / min for 30 minutes to ensure a strict inert atmosphere in the quartz tube.

[0032] Specific implementation method five: Combination Figure 1-Figure 2The present embodiment is described as a method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system. The temperature in the furnace chamber is increased to 800° C. by a tubular furnace at a heating rate of 10° C. / min.

[0033] Specific implementation method six: Combination Figure 1-Figure 2 The present embodiment is described as a method for promoting hydrogen production by a sludge and endocrine disruptor-pyrolysis coupling system, wherein the pyrolysis duration is 30 minutes, so that the sludge powder and 2,6-DCP fully react at high temperature and produce hydrogen-rich gas.

[0034] In order to ensure the smooth generation of pyrolysis products, sludge was first collected from the actual environment and its components were analyzed. The test sludge samples were taken from a sewage treatment plant in Harbin City, and the dehydrated sludge was dehydrated by a plate and frame filter press. The collected test sludge samples were tested and analyzed using air-dried basis, dry basis, and weight method. The results are shown in Table 1:

[0035]

[0036] From the data in the table, it can be seen that the moisture content of the dehydrated sludge is greater than 60%, which meets the characteristics of the sludge in the sewage treatment plant after mechanical dehydration. The moisture content of the sludge after drying is 2.12%. The low moisture content is conducive to reducing the energy input in the startup stage of the pyrolysis system and meeting the pyrolysis system's requirements for the moisture content of the feed sludge. The volatile content of the sludge is 46.55%, which provides sufficient substrate for the generation of pyrolysis products.

[0037] Example 1

[0038] A method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system, comprising the following steps:

[0039] Step 1: Place the dehydrated sludge after plate and frame filter pressing in an oven at 105°C for 24 hours, grind the sludge in a grinder and sieve it to obtain dry sludge powder;

[0040] Step 2: Add 2,6-DCP to the dry sludge powder, move it to a constant temperature rotary oscillator at a temperature of 50°C, and rotate it at a speed of 200 rpm for 30 minutes to evenly mix the 2,6-DCP and the dry sludge powder. The content of 2,6-DCP in the dry sludge powder is 10%-30%;

[0041] Step 3: Put the evenly mixed dry sludge powder into a quartz boat, place it at the left end of the quartz tube in the tube furnace, and introduce high-purity nitrogen into the quartz tube at a flow rate of 100 mL / min for 30 minutes;

[0042] Step 4: Heat the tube furnace at 10°C / min. After heating to 800°C, push the quartz boat containing dry sludge powder into the center of the furnace chamber to start pyrolysis. The pyrolysis time is 30 minutes, and hydrogen-rich gas is generated.

[0043] Comparative Example 1

[0044] The addition of 2,6-DCP in step 2 was not performed, and the other steps and parameters were the same as those in Example 1.

[0045] In order to better reflect the advantages of the sludge and endocrine disruptor-pyrolysis coupling system in hydrogen production, the changes in the content of gas components in the sludge pyrolysis process were investigated. The generated gas products were analyzed by gas chromatography CG method, and it was found that 30% 2,6-DCP induced an increase in H2 yield by 27.47%. On the contrary, CO2, 2,6-DCP significantly inhibited the production of CO2, and the intervention of 30% 2,6-DCP resulted in a 34.93% reduction in CO2 yield. It can be inferred that the addition of 2,6-DCP in the present invention increases the hydrogen production efficiency during pyrolysis, promotes the value of sludge pyrolysis gas products as a new energy hydrogen energy reuse, improves the resource utilization capacity of activated sludge waste, and realizes the resource utilization of sludge.

[0046] The above contents are used to further illustrate the features and advantages of the present invention in combination with implementation cases, and do not mean that the present invention is limited to these specific scenarios. Therefore, in this field, technical improvements and replacements based on the present invention as the core are all within the protection scope of the present invention.

[0047] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be arranged and combined, and those skilled in the art can exhaust all possibilities based on the mathematical knowledge of arrangement and combination. Therefore, the present invention will no longer describe the technical solutions after arrangement and combination one by one, but it should be understood that the technical solutions after arrangement and combination have been disclosed by the present invention.

[0048] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system, characterized in that: The steps include: Step 1: Place the dehydrated sludge after plate and frame filter pressing in an oven for drying, grind the sludge in a grinder and sieve it to obtain dry sludge powder; Step 2: adding 2,6-DCP to the dry sludge powder, and moving the mixture to a constant temperature rotary oscillator to uniformly mix the 2,6-DCP in the dry sludge powder, wherein the content of 2,6-DCP in the dry sludge powder is 10%-30%; Step 3: put the evenly mixed dry sludge powder into a quartz boat, place it at the left end of the quartz tube in the tube furnace, and pass high-purity nitrogen into the quartz tube; Step 4: Heat up the tubular furnace, and after heating up, push the quartz boat containing the dry sludge powder into the center of the furnace chamber to start pyrolysis, generating hydrogen-rich gas.

2. The method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system according to claim 1, characterized in that: The oven temperature is 105°C and the drying time is 24h.

3. The method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system according to claim 1, characterized in that: The temperature of the constant temperature rotary oscillator was 50°C, the rotation speed was 200 rpm, and the rotation time was 0.5 h.

4. The method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system according to claim 1, characterized in that: High-purity nitrogen was ventilated at a flow rate of 100 mL / min for 30 min.

5. The method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system according to claim 1, characterized in that: The temperature in the tube furnace was raised to 800°C at a heating rate of 10°C / min.

6. The method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system according to claim 1, characterized in that: The pyrolysis duration was 30 min.

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