A method for promoting hydrogen production by a sludge and endocrine disruptor-pyrolysis coupling system

Abstract

The present invention relates to a method for producing hydrogen by co-pyrolysis of sludge and endocrine disruptors, and belongs to the technical field of solid waste resource utilization. The method solves the problems of low efficiency and long cycle of anaerobic fermentation hydrogen production formed by conventional technologies, as well as the great environmental harm of endocrine disruptors, including step one, screening, concentrating and drying the sludge to obtain a dry sludge sample, step two, setting and adding 2,6-DCP sludge content of 10%, 20% and 30%, and step three, constructing and operating a system for producing hydrogen by co-pyrolysis of endocrine disruptors and sludge. The present invention adopts a rapid pyrolysis method and an electric heating method, and the sludge is pyrolyzed after the temperature is rapidly raised to the target temperature, which reduces the time and economic cost of the pyrolysis process and realizes the efficiency of sludge treatment.

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, numerous factors, including daily life and industrial production, have resulted in the massive discharge of hazardous waste, such as sewage and sludge. Currently, sludge treatment technologies primarily focus on concentration, dehydration, digestion, pyrolysis, and drying. Among these technologies, sludge pyrolysis is highly favored due to its dual advantages of solid waste recycling and efficient energy recovery. Producing high-value products such as biochar, oil, and gas through sludge pyrolysis not only addresses sludge environmental pollution, achieving sludge reduction and harmlessness, but also enables the recycling of sludge resources. Therefore, sludge pyrolysis, as a treatment and recycling technology for sludge resources, will become a future trend in sludge treatment and disposal technologies.

[0003] Sludge pyrolysis technology, due to its high temperature, leads to high energy consumption and large investment, which makes it disadvantageous compared with other treatment methods. Therefore, how to reduce costs will become the key to the future large-scale application of pyrolysis technology.

[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 present invention is developed to address the low efficiency and long cycle times of anaerobic fermentation hydrogen production, as well as the significant environmental hazards of endocrine disruptors, associated with conventional technologies. A brief overview of the present invention is provided 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 identify key or important aspects 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: The dehydrated sludge after the plate and frame filter press is placed in an oven for drying. After drying, the sludge is ground in a grinder and sieved to obtain dry sludge powder;

[0009] Step 2: Add 2,6-DCP to the dry sludge powder, and transfer the mixture to a constant temperature rotary shaker 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: Place 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;

[0011] Step 4: Heat up the tube furnace, and after heating, push the quartz boat filled with 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 24 hours.

[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 quickly heat the sludge to the target temperature before pyrolysis, which reduces the time and economic cost of the pyrolysis process and realizes the efficiency of 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 This is a graph showing the proportions of biochar, bio-oil, and gas obtained after rapid pyrolysis of sludge and endocrine disruptors;

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

[0023] To make the objectives, technical solutions, and advantages of the present invention more clearly apparent, the present invention is described below using specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely illustrative and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present invention.

[0024] Specific implementation method 1: Combination Figure 1-Figure 2 This embodiment describes a method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system, comprising the following steps:

[0025] Step 1: The dehydrated sludge after the plate and frame filter press is placed in an oven for drying. After drying, the sludge is ground in a grinder and sieved to obtain dry sludge powder;

[0026] Step 2: Add 2,6-DCP to the dry sludge powder, and transfer the mixture to a constant temperature rotary shaker 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: Place 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;

[0028] Step 4: Heat up the tube furnace, and after heating, push the quartz boat filled with 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 This embodiment describes 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 This embodiment describes a method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system. The constant temperature rotary oscillator temperature is 50°C, the rotation speed is 200 rpm, 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 This embodiment describes 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 2This embodiment is described. In this embodiment, a method for promoting hydrogen production by a sludge and endocrine disruptor-thermal decomposition coupling system is provided. The temperature in the furnace chamber is raised to 800° C. in 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. The pyrolysis duration is 30 minutes, ensuring that the sludge powder and 2,6-DCP fully react at high temperature and produce hydrogen-rich gas.

[0034] To ensure the smooth generation of pyrolysis products, sludge was first collected from a real environment and analyzed for composition. The test sludge samples were taken from a sewage treatment plant in Harbin after being dehydrated by a plate and frame filter press. The collected test sludge samples were tested using air-dried basis, dry basis, and gravimetric methods. The results are shown in Table 1:

[0035]

[0036] The data in the table shows that the dewatered sludge has a moisture content greater than 60%, meeting the requirements for mechanically dewatered sewage treatment plant sludge. The dried sludge has a moisture content of 2.12%. This low moisture content helps reduce energy input during the pyrolysis system startup phase and meets the pyrolysis system's required moisture content for the feed sludge. The sludge's volatile matter content reaches 46.55%, providing ample substrate for the formation 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. After drying, grind the sludge in a grinder and sieve to obtain dry sludge powder;

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

[0041] Step 3: The evenly mixed dry sludge powder was placed in a quartz boat, which was placed at the left end of the quartz tube in the tube furnace. High-purity nitrogen was introduced 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 filled with dry sludge powder into the center of the furnace chamber to start pyrolysis. The pyrolysis time is 30 minutes, generating hydrogen-rich gas.

[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] To better demonstrate the advantages of the sludge and endocrine disruptor-pyrolysis coupling system in hydrogen production, the changes in gas component content during the sludge pyrolysis process were investigated. The generated gas products were analyzed using the gas chromatography-mass spectrometry (GC) method. The results showed that 30% 2,6-DCP induced a 27.47% increase in H2 yield. CO2, on the other hand, was significantly inhibited by 2,6-DCP. The addition of 30% 2,6-DCP resulted in a 34.93% decrease in CO2 yield. It can be inferred that the addition of 2,6-DCP in the present invention increases the hydrogen production efficiency during the pyrolysis process, promotes the reuse of sludge pyrolysis gas products as a new energy source, and improves the resource utilization capacity of activated sludge waste, thus achieving resource utilization of sludge.

[0046] The above content is to further illustrate the features and advantages of the present invention in combination with implementation examples, and does 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 scope of protection 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 permuted and combined. Those skilled in the art can exhaust all possibilities based on the mathematical knowledge of permutations and combinations. Therefore, the present invention will no longer describe the technical solutions after permutations and combinations one by one, but it should be understood that the technical solutions after permutations and combinations have been disclosed by the present invention.

[0048] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A method for promoting hydrogen production by coupling a sludge and endocrine disruptor-thermal decomposition system, characterized in that: The steps include: Step 1: The dehydrated sludge after the plate and frame filter press is placed in an oven for drying. After drying, the sludge is ground in a grinder and sieved to obtain dry sludge powder; Step 2: Add 2,6-DCP to the dry sludge powder, and transfer the mixture to a constant temperature rotary shaker 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: Place 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; Step 4: Heat up the tube furnace, and after heating, push the quartz boat containing the dry sludge powder into the center of the furnace chamber to start pyrolysis and produce 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 24 hours.

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 shaker 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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