Method for improving carbon sequestration, emission reduction and humification of manure compost

Abstract

The invention relates to the field of agriculture, and discloses a method for improving carbon sequestration, emission reduction and humification of manure compost. According to the method disclosed by the invention, two kinds of tailing residues (twinkling and basalt) are properly added in the manure composting process, so that negative influence on composting is avoided, and the effects of promoting carbon sequestration and emission reduction of manure composting and increasing the humification coefficient (especially basalt) can be achieved. Compared with the conventional manure composting process, the basalt is added, so that the decomposition of compost organic matters can be remarkably reduced, the total organic carbon content is increased, and the emission of CO2 and CH4 in the composting process is greatly reduced, thereby being beneficial to reducing the emission of greenhouse gases and realizing the full utilization of waste resources.

Description

Technical Field

[0001] The present invention relates to the field of agriculture, and in particular to a method for improving carbon fixation, emission reduction and humification of manure compost, which uses tailings residue as an additive to improve carbon fixation in the manure composting process, reduce CO2 and CH4 emissions, and promote the maturity of compost products. Background Art

[0002] With the continuous development of society and the increase in material demand, the livestock and poultry breeding industry has shown a trend of large-scale and intensive development, and the production of livestock and poultry manure has increased. If livestock and poultry manure and other breeding wastes are not handled in time, they will cause serious pollution to the environment. In order to achieve the sustainable development of animal husbandry, livestock and poultry manure must be properly disposed of. Aerobic composting technology has the advantages of relatively thorough harmless treatment of manure, high added value of manure, and good economic benefits. It is an efficient method for recycling livestock and poultry manure resources. Due to its low cost, aerobic composting has long been used to convert livestock and poultry manure into organic fertilizer, but traditional aerobic composting will decompose the carbon in the pile into greenhouse gases such as CO2 and CH4, resulting in a large loss of compost carbon. Studies have shown that the amount of CH4 produced during aerobic composting accounts for about 0.8-6% of the total carbon, but its global warming potential is 25-28 times that of CO2, exacerbating the greenhouse effect. In addition, the humification degree of traditional aerobic composting is low, and the use of incompletely decomposed compost products will have an adverse effect on the growth and development of crops. Therefore, studying how to reduce carbon emissions during composting, increase carbon fixation and compost humification, and reduce greenhouse gas emissions is crucial to improving compost quality, improving environmental quality, and promoting the recycling of organic waste resources.

[0003] In recent years, reducing greenhouse gas emissions from composting and improving compost maturity by using exogenous additives has been a hot topic in this research field. The results of Jindo et al. showed that adding 10% biochar to compost is beneficial to the increase of aromatic carbon and carboxyl carbon content in fulvic acid. In addition to carbon-rich materials such as biochar, some mineral materials have also received continuous attention due to their high resource utilization, large specific surface area, high porosity and low cost. However, at present, the research on the effect of mineral materials on aerobic composting of livestock and poultry manure is more focused on nitrogen transformation. For example, Liu et al. studied the effect of clay on the abundance of nitrogen cycle-related functional genes during chicken manure composting; while there are few reports on increasing carbon fixation and improving humification in livestock and poultry manure composting.

[0004] The annual output of tailings residue is huge. Traditional methods of tailings comprehensive utilization include valuable component recovery, underground mine filling, mine vegetation reclamation, etc. These treatment methods are very likely to produce a large amount of tailings accumulation and cause environmental pollution. At present, tailings are used in the agricultural field, mainly using the trace elements necessary for plant growth such as Zn, Mn, Cu, Mo, P contained in the tailings, which are processed into fertilizers to achieve the effect of improving soil fertility. Whether it is possible to combine the treatment of tailings residues with the composting of livestock and poultry manure, and to achieve the joint treatment of the two wastes at the same time, and to improve the carbon fixation and emission reduction potential of composting and the quality of composting products is a topic worthy of research. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a method for improving carbon fixation, emission reduction and humification of manure composting. The present invention finds that adding two kinds of tailings residues (diorite and basalt) in appropriate amounts during the manure composting process will not only not have a negative impact on the composting, but also promote carbon fixation and emission reduction in manure composting and improve the humification coefficient (especially basalt). Compared with conventional manure composting processes, the addition of basalt can increase carbon fixation, significantly reduce total organic carbon losses during composting, significantly reduce CO2 and CH4 emissions, promote humification and maturity of compost products, and improve the quality of manure organic fertilizer, thereby helping to reduce greenhouse gas emissions during the process of waste fertilizerization.

[0006] The specific technical scheme of the present invention is: In a first aspect, the present invention provides a method for improving carbon fixation, emission reduction and humification of manure compost, comprising the following steps: 1) Composting: livestock manure, tailings residue and conditioner are used as composting raw materials, which are put into a composting device, mixed evenly and inoculated with microbial agents (composting agents). The tailings residue is basalt powder and / or diorite powder.

[0007] 2) Under the condition that the top of the composting device is sealed, bottom aeration is carried out.

[0008] Through research, the present invention found that adding two tailings residues (diorite and basalt) in the process of manure composting will not only have no negative impact on the composting, but also promote carbon fixation and emission reduction in manure composting and improve the humification coefficient (especially basalt). Compared with conventional manure composting technology, the addition of basalt can significantly increase carbon fixation during composting, reduce total organic carbon loss, and significantly reduce CO2 and CH4 emissions during composting, which is conducive to reducing greenhouse gas emissions and achieving full utilization of waste resources.

[0009] Preferably, in step 1), the basalt powder has a Mg content of 10-20wt%, a Si content of 40-50wt%, a Fe content of 20-30wt%, and a Ca content of 5-10wt%; the diorite powder has a Si content of 70-80wt%, and an Al content of 15-25wt%.

[0010] Preferably, in step 1), the content of tailings residue in the composting raw material is 5-15wt%.

[0011] Preferably, in step 1), the tailings residue is basalt powder.

[0012] The present invention has found in experiments that, compared with diorite, basalt has better comprehensive effects.

[0013] Preferably, in step 1), the conditioning agent is sawdust.

[0014] Preferably, in step 1), the moisture content of the compost raw material is 55-65wt%, and the C / N ratio is 30-35:1.

[0015] Preferably, in step 1), the mass ratio of the compost raw material to the microbial agent is (1-1.5)×103:1.

[0016] Preferably, in step 2), the aeration rate of the aeration is 0.28 L·kg -1 ·min -1 , aeration time is 5-20min.

[0017] Preferably, in step 3), the composting time is 25-40 days.

[0018] In a second aspect, the present invention provides the use of the compost product obtained by the above method in promoting the germination of crop seeds.

[0019] Preferably, the crop seeds are radish seeds or cabbage seeds.

[0020] The present invention has found through experiments that the compost products with basalt and diorite added have a significant promoting effect on the germination of radish seeds. The compost products with basalt added have a significant promoting effect on the germination of cabbage seeds. Therefore, the compost with basalt and diorite added is not only harmless to radish and cabbage seeds, but also the basalt compost products are more conducive to seed germination than conventional compost products.

[0021] In a third aspect, the present invention provides the use of basalt powder and / or diorite powder in reducing organic matter loss during manure composting and promoting the accumulation of nitrogen, phosphorus and potassium nutrients.

[0022] The present invention has found through experiments that the addition of basalt powder and / or diorite powder can reduce the organic matter and total nutrient content of nitrogen, phosphorus and potassium in the compost raw materials in the early stage due to the dilution effect. However, tailings residue can promote the accumulation of organic matter and nutrients in the compost or reduce the loss by affecting the composting process.

[0023] In a fourth aspect, the present invention provides the use of basalt powder in reducing the emission of CO2 gas and / or CH4 gas during manure composting.

[0024] The present invention has found through experiments that the addition of basalt can effectively reduce the emission of CO2 and CH4 during manure composting, while the effect of diorite is not significant.

[0025] In a fifth aspect, the present invention provides the use of basalt powder and / or diorite powder in promoting the accumulation of insoluble organic carbon in the process of manure composting.

[0026] The present invention has found through experiments that the addition of basalt powder and / or diorite powder contributes to the accumulation of total organic carbon in compost, but it is mainly insoluble organic carbon and has no obvious effect on the accumulation of soluble organic matter. In addition, compared with conventional compost, the aromatic carbon content of composting with the addition of basalt powder and / or diorite powder is higher, indicating that the addition of tailings residue increases the formation of stable organic matter in compost. In addition, the content of lignin, cellulose, hemicellulose and other difficult-to-degrade organic matter in the composting treatment with the addition of tailings residue is reduced, and the content of hydroxyl carbon and carboxyl carbon is increased, indicating that the addition of tailings residue promotes the decomposition of cellulose, hemicellulose and lignin in the pile, and converts them into available organic carbon. The transformation of easily decomposable organic matter to stable organic matter is an important indicator of compost maturity. Therefore, the addition of tailings residue helps to promote compost maturity, among which basalt is better than diorite.

[0027] In a sixth aspect, the present invention provides the use of basalt powder and / or diorite powder in enhancing moisture removal from manure composting.

[0028] The present invention has found through experiments that the addition of basalt powder and / or diorite powder has no significant effect on the temperature and pH of the compost, but has a significant effect on removing moisture from the compost.

[0029] In a seventh aspect, the present invention provides the use of basalt powder and / or diorite powder in improving the humification coefficient of manure compost products.

[0030] The present invention has found through experiments that the addition of basalt powder and / or diorite powder can significantly improve the humification coefficient of compost, and rapid humification mainly occurs during the 13-42 days of composting.

[0031] Compared with the prior art, the beneficial effects of the present invention are: The present invention found that adding two tailings residues (diorite and basalt) in the process of manure composting will not only have no negative impact on the composting, but also promote the carbon fixation and emission reduction of manure composting and improve the humification coefficient. Compared with the conventional manure composting process, the addition of basalt can significantly reduce the decomposition of compost organic matter, increase the total organic carbon content, and significantly reduce CO2 and CH4 emissions during the composting process, which is conducive to reducing greenhouse gas emissions and achieving full utilization of waste resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Detailed Description of the Invention The diagrams are energy spectrum diagram of basalt (upper left), energy spectrum diagram of diorite (upper right), specific surface area and pore size analysis diagram of basalt (lower left), and specific surface area and pore size analysis diagram of diorite (lower right) in the embodiments of the present invention.

[0033] Figure 2 Graph showing the changes in temperature (a), pH (b) and moisture (c) for different composting treatments in the embodiments of the present invention; wherein different lowercase letters in the graph indicate significant differences between different treatment groups at the P<0.05 level.

[0034] Figure 3 Graph showing changes in total nitrogen (a), total phosphorus (b), total potassium (c), total nutrients (d) and organic matter (e) content in different composting treatments in the embodiments of the present invention; wherein different lowercase letters in the graph indicate significant differences between different treatments at the P<0.05 level.

[0035] Figure 4 Graph showing the changes in CO2 emission rate (a) and cumulative emission (b) for different composting treatments in the embodiments of the present invention; wherein different lowercase letters in the graph indicate significant differences between different treatments at the P<0.05 level.

[0036] Figure 5 Graph showing the changes in CH4 emission rate (a) and cumulative emission (b) for different composting treatments in the embodiments of the present invention; wherein different lowercase letters in the graph indicate significant differences between different treatments at the P<0.05 level.

[0037] Figure 6 Graph showing the changes in total organic carbon (a) and soluble organic carbon (b) in different composting treatments in the embodiments of the present invention; wherein different lowercase letters in the graph indicate significant differences between different treatments at the P<0.05 level.

[0038] Figure 7 1 is a graph showing changes in the humification coefficient (c) of different composting treatments in the embodiments of the present invention; wherein different lowercase letters in the graph indicate significant differences between different treatments at the P<0.05 level. DETAILED DESCRIPTION

[0039] The present invention will be further described below in conjunction with the embodiments.

[0040] Overall embodiment In a first aspect, a method for improving carbon fixation, emission reduction and humification of manure compost using tailings residues comprises the following steps: 1) Composting: livestock manure, tailings residue and conditioner are used as composting raw materials, which are put into a composting device for uniform mixing and inoculation of microbial agents. The tailings residue is basalt powder and / or diorite powder, and basalt powder is more preferably used.

[0041] In some specific implementation cases, the basalt powder has a Mg content of 10-20wt%, a Si content of 40-50wt%, a Fe content of 20-30wt%, and a Ca content of 5-10wt%; the diorite powder has a Si content of 70-80wt%, and an A1 content of 15-25wt%.

[0042] In some specific implementation cases, the content of tailings residue in the composting raw material is 5-15wt%.

[0043] In some specific implementation cases, the conditioning agent is sawdust.

[0044] In some specific implementation cases, the moisture content of the compost raw material is 55-65wt%, and the C / N ratio is 30-35:1.

[0045] In some specific implementation cases, the mass ratio of the compost raw material to the microbial agent is (1-1.5)×10 3 :1.

[0046] 2) Under the condition that the top of the composting device is sealed, bottom aeration is carried out.

[0047] In some specific implementation cases, the aeration rate of the aeration is 0.28 L·kg -1 ·min -1 , aeration time is 5-20min.

[0048] 3) After aeration is completed, the top seal of the composting device is removed to allow composting to ferment.

[0049] In some specific implementation cases, the composting fermentation time is 25-40 days.

[0050] In a second aspect, the compost product obtained by the above method is used to promote the germination of crop seeds.

[0051] In some specific implementation cases, the crop seeds are radish seeds or cabbage seeds.

[0052] Thirdly, the application of basalt powder and / or diorite powder in reducing the loss of organic matter in the process of manure composting and promoting the accumulation of nitrogen, phosphorus and potassium nutrients.

[0053] Fourthly, the application of basalt powder in reducing CO2 gas and / or CH4 gas emissions during manure composting.

[0054] Fifthly, the application of basalt powder and / or diorite powder in promoting the accumulation of insoluble organic carbon in the process of manure composting.

[0055] A sixth aspect is the use of basalt powder and / or diorite powder in enhancing moisture removal from manure composting.

[0056] Seventhly, the application of basalt powder and / or diorite powder in improving the humification coefficient of manure composting products.

[0057] Example (1) Test materials Fresh pig manure and sawdust were sourced from Hangzhou Wotu Organic Fertilizer Co., Ltd. Two different tailings residues were selected, the main components of which were diorite and basalt, respectively, both from Zhejiang Jiaotou Puxin Mining Co., Ltd. The basic physical and chemical properties of pig manure and sawdust raw materials are shown in Table 1.

[0058] Table 1: Basic properties of the test materials raw material pH Moisture content (%) Organic matter (%) Total carbon (%) Total nitrogen (%) Pig manure 7.6 75.77 80.5 30.122 2.531 Sawdust 6.9 6.85 93.8 45.110 0.263 Basalt tailings residue 9.1 0.12 7.6 1.081 0.003 Diorite tailings residue 8.2 0.33 0.5 1.283 0.012 (2) Composting method Composting is carried out aerobic fermentation using a composting device. In this experiment, pig manure is used as the composting raw material, sawdust is used as the conditioner, and the mixture is evenly mixed and the moisture content is controlled at about 60%, and the C / N ratio is controlled at 30-35:1. 13kg of mixed materials and 10g of microbial agent (composting agent) are added to each composting bucket. There are three different treatments in the experiment, namely CK (treatment without adding tailings residue), XW (adding 10% basalt tailings residue) and SC (adding 10% diorite tailings residue), and each treatment is repeated three times.

[0059] The compost aeration device is connected to the bottom of the compost and uses a blower to aerate the compost at a rate of 0.28 L kg -1 ·min -1 Aeration was performed at a constant rate for 10 min. During the aeration period, all the air holes on the top of the compost aeration device were closed. After the aeration was completed, the air holes were opened to allow natural circulation with the outside air. Sampling was carried out on the 0th, 7th, 13th, 18th, 22nd, 28th, 36th, and 42nd day of composting.

[0060] (3) Test methods and analysis methods (3.1) Gas collection and measurement: Gas was collected every day for the first two weeks of the test, two to three times a week for the next two weeks, and once a week for the last two weeks. The CO2 and CH4 emission rates were determined using a static chamber-gas chromatography method, and the calculation formula is as follows: In the formula, f i is the gas emission flux (mg·m -2 ·h -1 );ρ is the density of the measured gas under standard conditions (CO2 is 1.977kg·m -3 , CH4 is 0.717 kg·m -3 );Δc / Δt is the rate of change of gas molar concentration in the box with time (mol·L -1 ·min -1 ); V is the volume of the space above the compost pile in the compost bin when sampling (m 3 );273 / [273+(T1+T2+T3) / 3] is the temperature correction coefficient, and T1~T3 respectively represent the temperature (℃) in the compost barrel during gas extraction.

[0061] Cumulative emissions of CO2 and CH4 from composting: Where M is the cumulative gas emission (mg·m -2 ); F is the gas emission flux (mg·m -2 ·h -1 ) ; t is the sampling time (d); i is the number of samplings; n is the total number of gas samplings; t i+1 -t i is the number of days between two gas extractions; R is the time conversion factor.

[0062] (3.2) Determination of seed germination index: After the composting test fermentation is completed, the seed germination rate test is carried out. The calculation formulas of seed germination rate (SG) and germination index (GI) are as follows: (4) Results and analysis (4.1) Basic properties and physicochemical characterization of tailings residues As shown in Table 2, the heavy metal contents of the two types of tailings residues are lower than the risk values ​​set by GB15618-2018 for soil environmental quality and the limit indicators of heavy metals in organic fertilizers set by NY525-2021. Figure 1 The following are the basalt energy spectrum diagram (upper left), diorite energy spectrum diagram (upper right), basalt specific surface area and pore size analysis diagram (lower left) and diorite specific surface area and pore size analysis diagram (lower right) in the embodiment of the present invention. Figure 1As shown, basalt is rich in Mg, Fe and other substances, while diorite is relatively less. Basalt ore powder is rich in Mg (15.6%, wt), Si (47.05%, wt), Fe (24.01%, wt), and Ca (8.09%, wt), while diorite ore powder is mainly Si (76.17%, wt) and Al (20.88%, wt). The specific surface area, total pore volume and average pore size of basalt are all smaller than those of diorite. Basalt is mostly mesopores, while diorite contains mesopores and macropores. Basalt shows a stronger sequestration capacity after adsorbing gas, while diorite has a stronger adsorption capacity under high relative pressure, but may be more suitable for an environment with easy desorption. In summary, the content of mineral components in basalt is higher than that in diorite, and its gas sequestration capacity is better than that of diorite.

[0063] Table 2: Heavy metal content in tailings residue (mg kg -1 ) “-” indicates that there is no specific numerical standard (4.2) Effects of tailings residue on temperature, moisture and pH of pig manure composting Figure 2 Figure 2 is a graph showing the changes in temperature (a), pH (b) and moisture (c) of different composting treatments in the present invention; different lowercase letters in the graph indicate significant differences between different treatment groups at the P<0.05 level. Figure 2 (a) shows that the addition of tailings residue did not affect the temperature rise and high temperature process during the composting process. The highest temperatures of the control, basalt and diorite treatment composts were 54.1, 54.7 and 54.9℃, respectively. The high temperature above 50℃ lasted for 13 days. Figure 2 As shown in (b), there was no significant difference in pH value between different treatments at 0d and 42d of composting. The pH values ​​of the compost products of the control, basalt and diorite treatments were 7.91, 7.92 and 7.99, respectively. Figure 2 (c) As shown. The moisture content of the compost products treated with basalt and diorite was significantly lower (P<0.05) than that of the control. The moisture removal rates of the control, basalt and diorite before and after composting were 29.4%, 36.8% and 32.8%, respectively. The moisture removal rates of basalt and diorite were significantly higher than those of the control. In summary, the addition of tailings residue had no significant effect on the temperature and pH of pig manure composting, and tailings residue had a significant effect on the removal of moisture in compost.

[0064] (4.2) Effects of tailings residues on nutrients and maturity of compost products (4.2.1) Organic matter and nutrient content of compost Figure 3Figure 2 is a graph showing the changes in total nitrogen (a), total phosphorus (b), total potassium (c), total nutrients (d) and organic matter (e) content in different composting treatments in the present invention; different lowercase letters in the graph indicate significant differences between different treatments at the P<0.05 level. Figure 3 As shown. From the beginning to the end of composting, the reduction ratio of organic matter content in the control, basalt and diorite treatments was 15.6%, 2.6% and 5.8%, respectively. The reduction ratio of organic matter in the treatment with tailings residue was significantly lower (P<0.05) than that in the control. In terms of total nutrients of nitrogen, phosphorus and potassium, the total nutrient contents of the control, basalt and diorite treatments were 8.4%, 7.4% and 7.6% on the 42nd day of composting, respectively. There was no significant difference in the total nitrogen, total phosphorus and total potassium before and after composting among the three treatment groups, but the growth rate of total phosphorus content in the basalt treatment was significantly higher (P<0.05) than that in the other two treatments. The growth rates of total nutrient content in the control, basalt and diorite treatments before and after composting were 101%, 114.6% and 82.2%, respectively. The growth rate of the diorite treatment was significantly lower (P<0.05) than that in the control and basalt treatments. In summary, due to the dilution effect, the addition of tailings residues will reduce the organic matter and total nutrient content of nitrogen, phosphorus and potassium in the compost raw materials. However, tailings residues can reduce the loss of organic matter in the compost and promote the accumulation of nitrogen, phosphorus and potassium nutrients by affecting the composting process.

[0065] (4.2.2) Evaluation of seed germination index The seed germination index of the control, basalt and diorite compost products is shown in Table 3. The germination index of radish seeds treated with basalt and diorite was significantly higher (P<0.05) than that of the control. The germination index of cabbage seeds treated with basalt was also significantly higher (P<0.05) than that of the control. In summary, basalt compost products are more conducive to seed germination and have better maturity than single pig manure compost products.

[0066] Table 3: Effects of different composting treatments on seed germination rate and germination index (%) Note: Different lowercase letters indicate significant differences between treatments at the P<0.05 level. (4.3) Changes in CO2 and CH4 emissions during composting (4.3.1) Changes in CO2 emissions during composting Figure 4 Figure 2 is a graph showing the changes in CO2 emission rate (a) and cumulative emission (b) of different composting treatments in the present invention; different lowercase letters in the graph indicate significant differences between different treatments at the P<0.05 level. Figure 4 The average emission rates of the control, basalt, and diorite treatment groups were 22.4, 19.8, and 22.2 g·m-2 ·h -1 The average emission rate of basalt was significantly (P<0.05) lower than that of the other two treatments. The order of the cumulative CO2 emissions of different treatments was control> diorite> basalt, and the cumulative CO2 emissions of basalt composting were significantly (P<0.05) lower than those of the other two groups. Therefore, the addition of basalt tailings residue can effectively reduce CO2 emissions during composting, while the effect of diorite is not significant.

[0067] (4.3.2) Changes in CH4 emissions during composting Figure 5 Graph showing the changes in CH4 emission rate (a) and cumulative emission (b) for different composting treatments in the embodiments of the present invention; wherein different lowercase letters in the graph indicate significant differences between different treatments at the P<0.05 level.

[0068] The CH4 emission rate and cumulative emission during composting are as follows: Figure 5 The maximum CH4 emission rates of the control, basalt and diorite treatment groups were 1111.3, 1027.7 and 1192.8 mg·m -2 ·h -1 .Depend on Figure 5 (b) It can be seen that the order of the cumulative CH4 emissions of different treatments is control > diorite > basalt, and the cumulative CH4 emissions of the basalt treatment are significantly lower than those of the other two groups (P<0.05). Therefore, the addition of basalt tailings can effectively reduce the emission of CH4 during composting, while the effect of diorite is not significant.

[0069] (4.4) Changes in carbon content in different forms of compost (4.4.1) Changes in total organic carbon and soluble organic carbon content Figure 6 Figure 2 is a graph showing the changes in total organic carbon (a) and soluble organic carbon (b) in different composting treatments in the present invention; different lowercase letters in the graph indicate significant differences between different treatments at the P<0.05 level. Figure 6 As shown. From the beginning to the end of composting, the total organic carbon loss rates of the control, basalt and diorite treatment groups were 15.6%, 2.9% and 5.6%, respectively. At 42 days of composting, there was no significant difference (P<0.05) in the total organic carbon content between the control and basalt treatment groups. However, the soluble organic carbon loss rates of the control, basalt and diorite treatment groups before and after composting were 20%, 20% and 26%, respectively. Therefore, the addition of tailings residues contributes to the accumulation of total organic carbon in compost.

[0070] (4.4.2) Humification coefficient Figure 7: is a graph showing the changes in the humification coefficient (c) of different composting treatments in the embodiment of the present invention; wherein different lowercase letters in the graph indicate significant differences between different treatments at the P<0.05 level. Figure 7 As shown. The humification coefficient (HI) was calculated based on the humic acid carbon and fulvic acid carbon content. It was found that the humification coefficients of the control, basalt and diorite compost products were 1.6, 2.5 and 2.3, respectively. The humification coefficient of the control compost product was significantly (P<0.05) lower than that of the basalt and diorite treatments. Compared with the control, the humification coefficients of the basalt and diorite treatments increased by 56.3% and 43.8%, respectively. Therefore, the addition of tailings residue significantly improved the humification coefficient of compost.

[0071] (4.4.3) Changes in compost organic carbon components Compared with the control group, the content of aromatic carbon and hydroxyl carboxyl carbon in the composting treatment with the addition of tailings residue was higher, indicating that the addition of tailings residue increased the formation of stable organic matter in the compost. In addition, the content of refractory organic matter such as lignin, cellulose and hemicellulose in the composting treatment with the addition of tailings residue decreased, and the content of aromatic carbon, hydroxyl carbon and carboxyl carbon increased, indicating that the addition of tailings residue promoted the decomposition of cellulose, hemicellulose and lignin in the pile and converted them into available organic carbon. Therefore, the effect of the addition of tailings residue on the carbon spectrum further reflects that the addition of basalt and diorite helps to promote the maturity of compost. Among them, basalt is better than diorite.

[0072] Table 4: Relative proportions of functional groups in compost products treated with different methods (%) The raw materials and equipment used in the present invention, unless otherwise specified, are all commonly used raw materials and equipment in the art; the methods used in the present invention, unless otherwise specified, are all conventional methods in the art.

[0073] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent transformation made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for improving carbon fixation, emission reduction and humification of manure compost, characterized in that include: 1) Composting: Use livestock manure, tailings residues and conditioners as composting raw materials, put them into composting equipment and inoculate microbial agents; The tailings residue is basalt powder and / or diorite powder; 2) Carry out bottom aeration under the condition that the top of the composting device is sealed.

2. The method according to claim 1, characterized in that: In step 1), The basalt powder has a Mg content of 10-20wt%, a Si content of 40-50wt%, a Fe content of 20-30wt%, and a Ca content of 5-10wt%; The diorite powder has a Si content of 70-80wt% and an Al content of 15-25wt%.

3. The method according to claim 1 or 2, characterized in that: In step 1), the content of tailings residue in the composting raw material is 5-15wt%.

4. The method according to claim 1, characterized in that: In step 1), The conditioning agent is sawdust; The compost raw material has a moisture content of 55-65wt% and a C / N ratio of 30-35:1; The mass ratio of the compost raw material to the microbial agent is (1-1.5)×10 3 :

1.

5. Use of the compost product obtained according to the method according to any one of claims 1 to 4 in promoting the germination of crop seeds.

6. Application of basalt powder and / or diorite powder in reducing organic matter loss during manure composting and promoting the accumulation of nitrogen, phosphorus, potassium nutrients and soluble organic carbon.

7. Application of basalt powder in reducing CO2 gas and / or CH4 gas emissions during manure composting.

8. Use of basalt powder and / or diorite powder to enhance moisture removal from manure composting.

9. The application of basalt powder and / or diorite powder in improving the humification coefficient of manure compost products.

Images