CN114715879A - Method for treating oil-based rock debris and biochar prepared by method - Google Patents

Method for treating oil-based rock debris and biochar prepared by method Download PDF

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CN114715879A
CN114715879A CN202210464747.7A CN202210464747A CN114715879A CN 114715879 A CN114715879 A CN 114715879A CN 202210464747 A CN202210464747 A CN 202210464747A CN 114715879 A CN114715879 A CN 114715879A
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biochar
oil
pyrolysis
biogas
rock debris
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CN114715879B (en
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陈柯锦
谭涵月
李源
曹会琳
陈相乐
李钰婷
蒋娇娇
王翔
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Chongqing University
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/05—Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/28—Treatment of water, waste water, or sewage by sorption
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/28—Treatment of water, waste water, or sewage by sorption
    • C02F1/283—Treatment of water, waste water, or sewage by sorption using coal, charred products, or inorganic mixtures containing them
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
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Abstract

The invention relates to a method for treating oil-based rock debris and biochar prepared by the method, and belongs to the field of environmental protection. The invention provides a method for treating oil-based rock debris, which comprises the following steps: A. uniformly mixing the oil-based detritus pyrolysis residue and the biogas residue in proportion to obtain co-pyrolysis residue; B. putting the co-decomposition slag into a closed container, and keeping inert atmosphere; C. and (4) heating to the co-decomposition temperature, maintaining the constant temperature, and cooling to obtain the biochar. The method for treating the oil-based rock debris is simple, can simultaneously treat two waste residues of the oil-based rock debris and the biogas residues, reduces the treatment cost, reduces the pollution of wastes, and realizes double waste recycling treatment. Meanwhile, the biochar prepared by the method for treating the oil-based rock debris is excellent in performance.

Description

Method for treating oil-based rock debris and biochar prepared by same
Technical Field
The invention belongs to the field of environmental protection, and relates to a method for treating oil-based rock debris and biochar prepared by the method.
Background
The drilling cuttings are produced during drilling and are a mixture of artificially added drilling mud and natural formation cuttings returned from the wellbore. According to statistics, the amount of water-based rock debris generated by single-well clean water drilling and water-based drilling in Chongqing areas is about 960m3The single well oil-based debris production is about 258m3. By 2021, Fuling shale gas field has successfully completed drilling shale gas well 421 mouths, according to the data, the water-based cuttings and oil-based cuttings generated at present are about 3 × 105m3And 8X 104m3. Oil-based v rock debris is brought into hazardous waste for management (national hazardous waste list, HW08) because of the fact that oil-based v rock debris contains pollutants such as petroleum hydrocarbons, heavy metals and organic matters, and compared with water-based rock debris, the oil-based v rock debris contains pollutants such as oil, heavy metals and salt ions which enter groundwater of a well site area or surface water such as rivers and lakes under the scouring action of rainwater, so that the quality of a drinking water source is affected, the normal growth and development of animals and plants in the water body are damaged, and the heavy metal ions can also damage human health through a food chain. Furthermore, diesel oil from oil-based drilling fluids reduces soil wettability, inhibits germination of crops and plants and even causes seed death, and can be harmful to human health if contacted with diesel oil for a long time.
At present, the harmless treatment method of the waste oil-based rock debris mainly comprises the following steps: incineration treatment, heat treatment, a chemical demulsification method, a solvent extraction method and the like. The method does not recycle a large amount of oil gas substances, not only causes serious waste of resources, but also can generate strong carcinogenic substances, namely dioxin, to pollute the atmospheric environment in the combustion process, and also can generate a large amount of greenhouse gas, namely carbon dioxide. The chemical demulsification method is characterized in that a solution of a surfactant and other auxiliaries is used for washing, and then solid-liquid separation is carried out through an air flotation or cyclone process. Other chemical processes usually require the use of toxic or harmful chemicals, the addition of chemicals can increase the amount of waste and complicate the problem, and the chemicals used in chemical processes are highly specific and not universally applicable. The solvent extraction method has the advantages of simple required conditions, low requirements on equipment, easiness in realization, high oil recovery rate and recyclable solvent, but the solvent used in the extraction process has high volatility and high energy consumption, so that the treatment cost is high. In addition, the solvent extraction method has the advantages of longer process flow, higher treatment cost and high energy consumption, and the requirements of requiring equipment to be conveniently constructed in the field and occupying as small as possible are not matched. The heat treatment method is simple in process, oil organic pollutants in the rock debris can be removed completely theoretically, the oil-based drilling cuttings are heated to the oil-water vaporization temperature through the external heating medium, oil and water escape from the oil-based drilling cuttings in a steam form, an oil product obtained through condensation does not need secondary treatment, the impurity content is low, and the oil product can be used as fuel or other chemical raw materials directly.
The existing pyrolysis method has the problems of complicated treatment steps, high equipment cost and the like. At present, the oil-based rock debris is up to 3000-5000 yuan/m3The treatment cost of (2) also increases the economic burden of waste treatment for shale gas development enterprises.
Therefore, it is an urgent problem to be solved in the art to provide a simple, pollution-free and low-cost method for treating oil-based cuttings.
Disclosure of Invention
The technical problems to be solved by the invention are as follows: provides a simple and pollution-free oil-based rock debris treatment method. The invention relates to a treatment method of oil-based rock debris, which is biochar prepared by a co-pyrolysis method of kitchen waste anaerobic digestion biogas residues and oil-based rock debris pyrolysis residues. Reduces the pollution of the waste while reducing the treatment cost, and realizes double waste recycling treatment.
The technical scheme of the invention is as follows:
method of treating oil-based cuttings: adding biogas residue.
Namely, in the process of treating the oil-based rock debris, biogas residues are introduced.
Further, according to the method for treating the oil-based rock debris, the biogas residues are added and then co-pyrolyzed to obtain the biochar.
As a preferable scheme, the method for treating the oil-based rock debris comprises the steps of converting the oil-based rock debris into oil-based rock debris pyrolysis slag before adding the biogas residue, and then adding the biogas residue.
The method for converting the oil-based detritus into the oil-based detritus pyrolytic residue comprises the following steps: pyrolyzing the oil-based rock debris at 400-600 ℃ to obtain solid residues; preferably a solid residue after pyrolysis at 450 ℃.
The biogas residues are dehydrated kitchen waste anaerobic fermentation solid-phase residues, namely the biogas residues are dried before co-pyrolysis.
Further, in the method for treating the oil-based rock debris, the addition amount of the biogas residues is 50-100% (w/w), and the addition amount of the biogas residues is not equal to 100%. Further, the preferable addition amount of the biogas residue is 50-95% (w/w), 50-90% (w/w), 50-70% (w/w) and 70-90% (w/w).
Furthermore, the weight sum of the oil-based detritus pyrolytic residue and the biogas residue is 100%, and the content of the oil-based detritus pyrolytic residue is more than 0%. Accordingly, the proportion of the oil-based rock debris pyrolytic slag is 5% to 50% (w/w), preferably 10% to 50% (w/w), more preferably 10% to 30% (w/w), and even more preferably 30% to 50% (w/w).
The method for treating the oil-based rock debris comprises the following steps:
(A) uniformly mixing the oil-based detritus pyrolysis residue and the biogas residue in proportion to obtain co-pyrolysis residue;
(B) putting the co-decomposition slag into a closed container, and keeping inert atmosphere;
(C) and (4) heating to the co-decomposition temperature, maintaining the constant temperature, and cooling to obtain the biochar.
Wherein, in the step A, the weight of the biogas residues is 50-100% (w/w). Further, the preferable addition amount of the biogas residues is 50-95% (w/w), 50-90% (w/w), 50-70% (w/w) and 70-90% (w/w);
in the step B, the inert atmosphere may be an atmosphere selected from an atmosphere containing nitrogen and/or other gases inert to the oil-based detritus pyrolysis residue and biogas residue, such as one or more of helium and neon;
further, in the step C, the co-decomposition temperature is 400-700 ℃, preferably 450-700 ℃, more preferably 500-700 ℃, and most preferably 600-700 ℃.
Preferably, in the step C, the constant temperature is maintained for 60-120 min, preferably 60-90 min, and more preferably 90-120 min.
Further, the method for treating the oil-based rock debris comprises the following steps:
(1) weighing biogas residues in the porcelain boat, weighing corresponding amount of pyrolysis residues according to the addition ratio, uniformly mixing, putting into a quartz tube of a horizontal tube furnace, and plugging heat insulation plugs at two ends;
(2) connecting flanges at two ends of the quartz tube, checking a gas path, opening a knob of a nitrogen steel cylinder, introducing N2 into the quartz tube at the speed of 0.4L/min, and maintaining the inert atmosphere in the whole pyrolysis process;
(3) and opening a heating switch of the tube furnace, setting a corresponding temperature-raising program, raising the temperature to the co-decomposition temperature at a temperature-raising rate of 10 ℃/min, and staying and maintaining at the co-decomposition temperature.
(4) And after pyrolysis, continuously keeping inert atmosphere, naturally cooling to obtain a mixed biochar sample, and sieving by a 100-mesh sieve for homogenization for later use.
Wherein the weight of the biogas residues is 50-100% (w/w). Further, the preferable addition amount of the biogas residue is 50-95% (w/w), 50-90% (w/w), 50-70% (w/w) and 70-90% (w/w).
In the step (3), the co-decomposition temperature is 400-700 ℃, preferably 450-700 ℃, more preferably 500-700 ℃, and most preferably 600-700 ℃.
Preferably, in the step (3), the constant temperature is maintained for 60 to 120min, preferably 60 to 90min, and more preferably 90 to 120 min.
In the step (3), the inert atmosphere may be an atmosphere selected from an atmosphere containing nitrogen and/or other gases inert to the oil-based detritus pyrolysis residue and biogas residue, such as one or more of helium and neon.
The ventilation speed and the heating speed can be determined according to the specific conditions of pipe diameter, pressure in the pipe and the like, and are not influenced by the numerical values.
The invention also discloses the biochar prepared by the method.
Further, the invention also provides a cadmium removing composition which comprises the biochar prepared by the method.
A method for adsorbing cadmium comprises the step of contacting the cadmium-containing medium with the biochar prepared by the method, for example, the cadmium-containing medium is a cadmium-containing liquid, such as cadmium-containing sewage.
The invention also discloses the application of the biochar prepared by the method in cadmium removal.
According to the preliminary adsorption research result of the prepared biochar sample on Cd (II) in the solution, the adsorption quantity of Cd (II) is taken as a screening index, and three biochar samples with different adsorption effects are selected to further research the influence of adsorption conditions on adsorbing Cd (II).
Investigation of adsorption conditions for Cd (II) adsorption:
preparing a cadmium-containing solution: accurately weighing cadmium nitrate (Cd (NO)3)2·4H2O)2.7492g, 0.1mol L-1 sodium nitrate (NaNO)3) After the solution is dissolved, the solution is moved into a 1L volumetric flask, and finally the solution is diluted to a marked line by using a sodium nitrate solution in a constant volume manner. The mass concentration of Cd (II) in the solution is about 1000mg/L, and the solution is used as a mother solution for the test solutions with different concentrations of Cd (II) required in the experiments.
(1) Influence of pH value of solution on adsorption of Cd (II) by charcoal
To avoid hydrolysis and precipitation of Cd (II), the initial pH of the Cd (II) test solution is set in an acidic range, and the initial pH of the Cd (II) test solution is adjusted to 2.5, 3.5, 4.5, 5.5 and 6.5 by using 0.1mol/L HCl and NaOH solutions. Accurately weighing 0.1000g of biochar sample in a 150mL conical flask, adding 30mL of Cd (II) test solution with the concentration of 100mg/L, and placing in a constant temperature shaking box to shake for 12h at the temperature of 25 ℃ and the rpm of 180. Transferring the mixture into a 50mL centrifugal tube after the oscillation is finished, placing the mixture into a centrifugal machine, centrifuging the mixture for 10min at 5000rpm, filtering the mixture by using a disposable filter with the pore diameter of 0.45 mu m, and collecting supernatant to be tested.
(2) Influence of adsorption time on adsorption of Cd (II) by charcoal
Accurately weighing 0.1000g of biochar sample in an erlenmeyer flask, adding 30mL of Cd (II) test solution with the concentration of 100mg/L, pH value of 5.5, placing the sample in a constant-temperature oscillation box at 25 ℃ to oscillate at 180rpm, sampling at set time respectively, centrifuging, filtering and then measuring. The time gradient is 10min, 25min, 45min, 75min, 120min, 240min, 360min, 480min, 720min and 1440 min.
(3) Influence of initial concentration of Cd (II) on adsorption of Cd (II) by charcoal
The Cd (II) mother liquor with the concentration of 1000mg/L is used for diluting to prepare Cd (II) test solutions with the initial concentrations of 10mg/L, 25mg/L, 50mg/L, 100mg/L, 200mg/L and 350mg/L, and the pH is adjusted to 5.5. Accurately weighing 0.1000g of biochar sample in an erlenmeyer flask, adding 30mL of Cd (II) test solution with different concentrations, and placing in a constant temperature shaking box at 25 ℃ to shake for 12h at 180 rpm. Transferring the mixture into a 50mL centrifugal tube after the oscillation is finished, placing the mixture into a centrifugal machine, centrifuging the mixture for 10min at 5000rpm, filtering the mixture by using a disposable filter with the pore diameter of 0.45 mu m, and collecting supernatant to be tested.
(4) Control adsorption test
0.1000g of biochar is weighed into an erlenmeyer flask, 30ml of sodium nitrate solution with the pH adjusted to 5.5 is added, and a control test is completed according to a corresponding set program so as to deduct the content of Cd (II) released by the biochar per se. Adding Cd (II) test solution with corresponding concentration and pH adjusted to 5.5 into the conical flask, and completing a blank control test according to a corresponding set program to deduct the adsorption amount of Cd (II) by the conical flask.
Through the research, the pH value of the selected Cd (II) solution is 5.5, the adsorption time is 12h, and the initial concentration of Cd (II) is 100 mg/L. Measuring Cd (II) content, adsorption removal rate and adsorption of the solution to be measured by an atomic absorption spectrophotometer
Figure BDA0003623383310000051
Figure BDA0003623383310000052
The attached capacity is calculated according to the following formula:
wherein the content of the first and second substances,
r: the removal rate of heavy metal ions by the biochar is percent;
c0: initial concentration of heavy metal solution, mg/L;
ce: the residual concentration of heavy metal in the solution after adsorption is mg/L;
qe: adsorption capacity, mg/g;
v: heavy metal solution volume, L;
m: the addition amount of the biochar, g.
The adsorption capacity of Cd (II) calculated by the formula is used for representing the adsorption capacity of the biochar, and the higher the adsorption capacity is, the stronger the adsorption capacity is; the adsorption removal rate is used for representing the removal rate of the heavy metal ions by the biological carbon, and the side surface reflects the adsorption performance of the biological carbon.
Meanwhile, the adsorption mechanism of the mixed biochar to Cd (II) in the solution is qualitatively analyzed by using microstructure characterization methods such as SEM, XRD, FTIR and the like, and the relative contribution of each adsorption mechanism is quantitatively analyzed.
FIGS. 1 to 4 are SEM images under different conditions, and FIG. 3 shows that the surface of biogas residue is dense, and FIG. 4 shows that the surface of oil-based detritus pyrolytic residue is smooth. FIG. 1 shows that the surface of the biochar prepared by separately pyrolyzing biogas residues is fluffy, and obvious layer-shaped appearance characteristics gradually appear on the surface of the biochar along with the increase of the pyrolysis temperature. In contrast, the surface of fig. 2 is smoother, and fine cracks and uniform distribution of fine pores can be observed, which indicates that the biochar prepared by the method of the present invention has better pore structure and roughness.
XRD patterns before and after the adsorption of the biochar are shown in figure 5. In B400-90-50, B450-90-5 and B600-90-10 (samples of co-pyrolysis biochar are named according to the format "B pyrolysis temperature-constant temperature time-oil-based rock debris pyrolysis slag weight ratio", as B400-90-50 indicates that the co-pyrolysis temperature is 400 ℃, the constant temperature time is 90min, and the oil-based rock debris pyrolysis slag weight ratio is 50% (w/w)), the presence of compounds such as CaCO3, SiO2, BaSO4, CaSO4, MgCO3 and MgSiO3 can be found. In the present study, from the three biochar after adsorption, the diffraction peaks of some CdS, CdO and CdCO3 can be matched from the XRD patterns. Comparing the XRD patterns before and after adsorption, it was found that the change was not significant, and it is likely that Cd adsorbed into biochar formed compound precipitates, but the formed precipitates were amorphous and failed to form crystals, and the XRD patterns showed diffraction peaks, which were often crystalline.
FIG. 6 is an infrared spectrum before and after adsorption of Cd (II) by three biochar, which reflects the change of the functional groups on the biochar surface before and after adsorption. As can be seen from the figure, the infrared spectrum of the three biochar before and after adsorption has little change, and B400-90-50 is only 1090cm-1The absorption peak is changed, and the B450-90-5 is 1478cm-1、1030cm-1、600cm-1The depth of the hole is changed, and B600-90-10 is mainly 3750cm-1～3410cm-1And 1030cm-1There is a change. 1090cm-1Is corresponding to sulfate radical (SO)4 2-) After Cd (II) is adsorbed, the absorption peak is weakened, probably because Cd (II) is combined with sulfate to form precipitate. In B450-90-5 and B600-90-10, 1030cm-1The absorption peak becomes broader and weaker after adsorption, and Cd (II) is probably combined with C-O groups in the carbon. 3750cm-1～3410cm-1Mainly O-H stretching vibration peak, and the reason for the change is probably that Cd (II) is complexed with organic functional groups on the carbon surface. The 600cm-1 is mainly the C-H bending vibration peak in the arene, and the change is probably due to the pi electron coordination effect of Cd (II) and the arene on the carbon surface. Thus, functional groups such as-OH, -CO, -CH and the like may participate in the binding of biochar to Cd (II) through ion exchange, surface complexation and cation-pi interaction.
FIG. 7 FTIR spectra before and after adsorbing Cd (II) by biochar, showing the surface morphology change before and after adsorption. Before adsorption, the surfaces of B400-90-50, B450-90-5 and B600-90-10 are smooth, and fine cracks and uniform distribution of micro pores can be observed. After adsorption was completed, attachment of small particle compounds was observed on the three biochar surfaces, filling the pore structure, making the biochar surface rougher. These small particles may result from Cd binding with minerals in the biochar to form new precipitated compounds.
Furthermore, the pH value of the biochar prepared by the method is measured, and the pH value of the biochar is 9.36-11.44.
According to the biochar prepared by the method, heavy metals (such as Ba, Cd, Cr, Cu, Mn, Ni, Pb, Zn, Hg and the like) enriched in the oil-based rock debris are enriched in the biochar along with the rise of temperature in the co-decomposition process, so that the recovery of the heavy metals in the raw materials is realized.
The ash content in the biochar is influenced by the pyrolysis temperature and the addition amount of pyrolysis residues of the oil-based rock debris, the ash content of the biochar is in a positive correlation with the pyrolysis temperature at each constant temperature time, the details are shown in figure 8, and the correlation coefficients are all above 0.9.
The analysis of the volatile content of the co-pyrolysis coal and the correlation between the volatile content and the pyrolysis temperature are shown in FIG. 9. The volatile matter of the biochar is related to the raw material composition and the pyrolysis temperature, the volatile matter content in the biochar is continuously reduced along with the rise of the pyrolysis temperature at each constant temperature, and the volatile matter content in the biochar is significantly negatively related to the pyrolysis temperature; the volatile matters in the biochar are gradually reduced along with the increase of the adding ratio of the pyrolysis residue at each constant temperature time.
According to the method, the biochar is prepared from the oil-based rock debris and the biogas residues, and the highest yield of the biochar can reach 76%.
Meanwhile, the oil-based rock debris pyrolysis residue and the biogas residue are co-decomposed to generate a synergistic effect, so that the prepared biochar has higher adsorption capacity. If the pyrolysis temperature is 600 ℃, the constant temperature time is 60min, and the weight of the pyrolysis slag and the biogas residue are both 50%, the adsorption quantity of the prepared biochar sample to Cd (II) is increased by 52.70% compared with the biochar adsorption quantity of the biogas residue at the corresponding temperature; when the pyrolysis temperature is 700 ℃, the constant temperature time is 120min, and the contents of the pyrolysis slag and the biogas residue are both 50%, the adsorption capacity of the prepared biochar sample on Cd (II) is improved by 4.2 times compared with the biochar adsorption capacity of the biogas residue at the corresponding temperature.
In addition, the other performances of the biochar prepared by the method are superior to those of biogas residue carbon (namely carbon obtained by singly utilizing the pyrolysis of biogas residue), and for example, the biochar obtained by the method has larger specific surface area, rich pore structure and the like.
It is to be noted that the method of the present invention has no particular limitation on the biogas residue and the oil-based rock debris, and for example, no particular requirements on the source, the components, and the like are required. In order to verify that biogas residues and pyrolysis residues from different sources can be suitable for the technical scheme, the biogas residues and the pyrolysis residues from different sources are adopted, and the components and the component contents of the biogas residues and the pyrolysis residues are different greatly and are not completely the same. Therefore, the prepared biochar has certain difference on Cd (II) adsorption capacity and the like, but any source and component can be applied to the method for treating the oil-based rock debris to obtain the biochar with more excellent performance compared with the biogas residue carbon.
The invention has the beneficial effects that:
(1) the method has simple steps, can realize resource utilization, can treat the oil-based rock debris pyrolysis slag and the biogas residue simultaneously, and realizes resource treatment of various wastes, namely 'treating wastes with wastes against one another and changing wastes into valuables'.
(2) The biochar obtained by pyrolysis in the technical scheme of the invention has the characteristics of high stability, large specific surface area, rich pore structure, strong adsorption capacity and the like, and has a good application prospect in heavy metal pollution remediation.
(3) The biochar prepared by the method has excellent Cd (II) adsorption capacity and adsorption removal rate.
Description of the drawings:
FIG. 1 shows SEM of 100% biogas residue carbon prepared from biogas residues at a temperature of 450 ℃ for 60 min.
FIG. 2 is an SEM of a co-decomposition temperature of 450 ℃, a co-decomposition time of 90min and an addition amount of 5% (w/w) of pyrolysis slag.
Figure 3 SEM of biogas residue feedstock.
FIG. 4 SEM of oil-based detritus pyrolyzation slag.
FIG. 5 SEM images of biochar before and after adsorption of Cd (II).
FIG. 6 is an infrared spectrum before and after adsorption of Cd (II) by charcoal.
FIG. 7 FTIR spectra before and after biochar adsorption of Cd (II).
FIG. 8 is a graph of correlation analysis of ash content of biochar and ash content with pyrolysis temperature.
FIG. 9 analysis of the volatile matter content of co-pyrolysis char and the correlation of volatile matter with pyrolysis temperature.
Detailed Description
The following examples are given to further illustrate the embodiments of the present invention and are not intended to limit the scope of the present invention.
Example 1 preparation of biogas residue
In the research, the biogas residues are obtained from a certain kitchen waste treatment plant and are collected from dehydrated solid residues obtained after anaerobic fermentation of kitchen waste, and the water content of the dehydrated biogas residues is about 58%. And taking back the biogas residue sample, naturally air-drying for 7 days at room temperature, crushing the biogas residue after air-drying, sieving with a 60-mesh sieve to homogenize, drying the homogenized biogas residue in an oven at 65 ℃ to constant weight, packaging in a sealed plastic bag, and storing in a dryer for later use. The basic properties and elemental composition of the biogas residue are shown in tables 1 and 2.
TABLE 1 basic Properties of biogas residues
Figure BDA0003623383310000081
TABLE 2 composition of main inorganic elements in biogas residue (%)
Figure BDA0003623383310000082
Example 2 preparation of oil-based debris pyrolytic slag
The oil-based detritus pyrolysis residue is solid residue of oil-containing detritus in certain shale gas production area after pyrolysis at 450 ℃, and the basic physicochemical properties and inorganic mineral composition are shown in tables 3 and 4 respectively. Taking back, sieving with 200 mesh sieve, and standing.
TABLE 3 fundamental physico-chemical Properties of the pyrolysis residue
Figure BDA0003623383310000083
Table 4 pyrolysis residue inorganic mineral composition (%)
Figure BDA0003623383310000084
Example 3 preparation of biochar
1. Weighing 9.5g of biogas residues in a porcelain boat, adding 0.5g of pyrolysis residues, uniformly mixing, putting into a quartz tube, and plugging heat insulation plugs at two ends; the pyrolysis residue is solid residue obtained by pyrolyzing the oil-based rock debris at 450 ℃, and is sieved by a 200-mesh sieve. The biogas residue is dehydrated kitchen waste anaerobic fermentation solid-phase residue;
2. after flanges at two ends of the quartz tube are connected and a gas path is checked, a knob of a nitrogen steel cylinder is opened, N2 is introduced into the quartz tube of the tube furnace at the speed of 0.4L/min, and the inert atmosphere in the whole pyrolysis process is maintained;
3. and opening a heating switch of the tube furnace, setting a corresponding temperature-raising program, raising the temperature to 400 ℃ at a temperature-raising rate of 10 ℃/min, and staying at the corresponding temperature for 120 min. And after pyrolysis, continuously keeping inert atmosphere, naturally cooling to obtain a mixed biochar sample, and sieving by a 100-mesh sieve for homogenization for later use.
The above parallel experiment was repeated 3 times, and the Cd (II) adsorption capacity and adsorption removal rate thereof were measured and calculated according to the following methods.
(1) Accurately weighing cadmium nitrate (Cd (NO)3)2·4H2O)2.7492g was put in a beaker, and 0.1mol of L-1 sodium nitrate (NaNO) was added3) After the solution is dissolved, the solution is transferred into a 1L volumetric flask, and finally the solution is diluted to a marked line by a sodium nitrate solution in a constant volume manner. The mass concentration of Cd (II) in the solution is about 1000mg/L, and in the following steps, the test solution of Cd (II) is the mother solution.
(2) The initial pH of the Cd (II) test solution was adjusted to 5.5 with 0.1mol/L HCl and NaOH solutions. Accurately weighing 0.1000g of biochar sample in a 150mL conical flask, adding 30mL of Cd (II) test solution with the concentration of 100mg/L, and placing in a constant temperature shaking box to shake for 12h at the temperature of 25 ℃ and the rpm of 180. Transferring the mixture into a 50mL centrifugal tube after the oscillation is finished, placing the mixture into a centrifugal machine, centrifuging the mixture for 10min at 5000rpm, filtering the mixture by using a disposable filter with the pore diameter of 0.45 mu m, and collecting supernatant to be tested.
(3) Control adsorption test
0.1000g of biochar is weighed into an erlenmeyer flask, 30ml of sodium nitrate solution with the pH adjusted to 5.5 is added, and a control test is completed according to a corresponding set program so as to deduct the content of Cd (II) released by the biochar per se. Adding Cd (II) test solution with corresponding concentration and pH adjusted to 5.5 into the conical flask, and completing a blank control test according to a corresponding set program to deduct the adsorption amount of Cd (II) by the conical flask.
Measuring the content of Cd (II) in the solution to be measured by adopting an atomic absorption spectrophotometer, and calculating the adsorption removal rate and the adsorption capacity according to the following formulas:
Figure BDA0003623383310000091
Figure BDA0003623383310000092
wherein the content of the first and second substances,
r: the removal rate of heavy metal ions by the biochar is percent;
c0: initial concentration of heavy metal solution, mg/L;
ce: the residual concentration of heavy metal in the solution after adsorption is mg/L;
qe: adsorption capacity, mg/g;
v: heavy metal solution volume, L;
m: the addition amount of the biochar, g.
After the average values of three parallel samples of the biochar prepared by the embodiment are obtained, the adsorption capacity of Cd (II) is 25.51mg/g, the adsorption removal rate is 57.12%, and the pH value of the biochar is 9.84.
Comparative example: under the same conditions, 100 percent of biogas residue biochar (the weight of biogas residue is 100 percent and 10 g; does not contain pyrolysis residue) has Cd (II) adsorption capacity of 22.64mg/g and adsorption removal rate of 50.15 percent.
Example 4 preparation of biochar
Experiments were performed according to the preparation method, test method and calculation method of example 3.
Wherein the weight of the pyrolysis residue is 1g, the weight of the biogas residue is 9g, the co-pyrolysis time is 60min, and the co-pyrolysis temperature is 450 ℃.
After the average value of three parallel samples of the biochar prepared by the embodiment is obtained, the adsorption capacity of Cd (II) is 34.18mg/g, the adsorption removal rate is 68.26%, and the pH value of the biochar is 9.43.
Comparative example: under the same conditions, the Cd (II) adsorption capacity of 100 percent biogas residue biochar is 32.62mg/g, and the adsorption removal rate is 64.31 percent.
EXAMPLE 5 preparation of biochar
Experiments were performed according to the preparation method, test method and calculation method of example 3.
Wherein the weight of the pyrolysis slag is 0.5g, the weight of the biogas slag is 9.5g, the co-pyrolysis time is 90min, and the co-pyrolysis temperature is 450 ℃.
After the average value of three parallel samples of the biochar prepared by the embodiment is obtained, the adsorption capacity of Cd (II) is 38.57mg/g, the adsorption removal rate is 72.62%, and the pH value of the biochar is 9.67.
Comparative example: under the same conditions, the adsorption capacity of Cd (II) of 100 percent biogas residue biochar is 32.73mg/g, and the adsorption removal rate is 61.70 percent.
EXAMPLE 6 preparation of biochar
Experiments were performed according to the preparation method, test method, and calculation method of example 3.
Wherein the weight of the pyrolysis slag is 1g, the weight of the biogas slag is 9g, the co-pyrolysis time is 120min, and the co-pyrolysis temperature is 450 ℃.
After the average value of three parallel samples of the biochar prepared by the embodiment is obtained, the adsorption capacity of Cd (II) is 29.57mg/g, the adsorption removal rate is 60.58%, and the pH value of the biochar is 9.85.
Comparative example: under the same conditions, the adsorption capacity of Cd (II) of 100 percent biogas residue biochar is 25.82mg/g, and the adsorption removal rate is 52.71 percent.
Example 7 preparation of biochar
Experiments were performed according to the preparation method, test method and calculation method of example 3.
Wherein the weight of the pyrolysis residue is 0.5g, the weight of the biogas residue is 9.5g, the co-pyrolysis time is 60min, and the co-pyrolysis temperature is 500 ℃.
After the average values of three parallel samples of the biochar prepared by the embodiment are obtained, the adsorption capacity of Cd (II) is 31.73mg/g, the adsorption removal rate is 57.88%, and the pH value of the biochar is 10.07.
Comparative example: under the same condition, the Cd (II) adsorption capacity of 100% biogas residue biochar is 25.58mg/g, and the adsorption removal rate is 44.04%.
EXAMPLE 8 preparation of biochar
Experiments were performed according to the preparation method, test method and calculation method of example 3.
Wherein the weight of the pyrolysis slag is 1g, the weight of the biogas slag is 9g, the co-pyrolysis time is 90min, and the co-pyrolysis temperature is 500 ℃.
After the average values of three parallel samples of the biochar prepared by the embodiment are obtained, the adsorption capacity of Cd (II) is 26.41mg/g, the adsorption removal rate is 45.87%, and the pH value of the biochar is 10.04.
Comparative example: under the same conditions, the adsorption capacity of Cd (II) of 100 percent biogas residue biochar is 22.20mg/g, and the adsorption removal rate is 36.57 percent.
Example 9 preparation of biochar
Experiments were performed according to the preparation method, test method and calculation method of example 3.
Wherein the weight of the pyrolysis slag is 5g, the weight of the biogas slag is 5g, the co-pyrolysis time is 120min, and the co-pyrolysis temperature is 500 ℃.
After the average value of three parallel samples of the biochar prepared by the embodiment is obtained, the adsorption capacity of Cd (II) is 22.16mg/g, the adsorption removal rate is 36.71%, and the pH value of the biochar is 10.79.
Comparative example: under the same conditions, the Cd (II) adsorption capacity of 100 percent biogas residue biochar is 21.77mg/g and the adsorption removal rate is 35.64 percent.
Example 10 preparation of biochar
Experiments were performed according to the preparation method, test method and calculation method of example 3.
Wherein the weight of the pyrolysis slag is 3g, the weight of the biogas slag is 7g, the co-pyrolysis time is 60min, and the co-pyrolysis temperature is 600 ℃.
After the average values of three parallel samples of the biochar prepared by the embodiment are obtained, the adsorption capacity of Cd (II) is 20.47mg/g, the adsorption removal rate is 45.85%, and the pH value of the biochar is 11.22.
Comparative example: under the same conditions, the Cd (II) adsorption capacity of 100% biogas residue biochar is 19.95mg/g, and the adsorption removal rate is 43.37%.
EXAMPLE 11 preparation of biochar
Experiments were performed according to the preparation method, test method and calculation method of example 3.
Wherein the weight of the pyrolysis slag is 5g, the weight of the biogas slag is 5g, the co-pyrolysis time is 90min, and the co-pyrolysis temperature is 600 ℃.
After the average values of three parallel samples of the biochar prepared by the embodiment are obtained, the adsorption capacity of Cd (II) is 31.85mg/g, the adsorption removal rate is 61.76%, and the pH value of the biochar is 11.2.
Comparative example: under the same conditions, the Cd (II) adsorption capacity of 100% biogas residue biochar is 14.96mg/g, and the adsorption removal rate is 33.64%.
EXAMPLE 12 preparation of biochar
Experiments were performed according to the preparation method, test method and calculation method of example 3.
Wherein the weight of the pyrolysis slag is 5g, the weight of the biogas residue is 5g, the co-pyrolysis time is 120min, and the co-pyrolysis temperature is 600 ℃.
After the average value of three parallel samples of the biochar prepared by the embodiment is obtained, the adsorption capacity of Cd (II) is 42.52mg/g, the adsorption removal rate is 84.20%, and the pH value of the biochar is 11.28.
Comparative example: under the same condition, the Cd (II) adsorption capacity and the adsorption removal rate of the 100 percent biogas residue biochar are 14.24mg/g and 24.38 percent respectively.
EXAMPLE 13 preparation of biochar
Experiments were performed according to the preparation method, test method, and calculation method of example 3.
Wherein the weight of the pyrolysis slag is 5g, the weight of the biogas slag is 5g, the co-pyrolysis time is 60min, and the co-pyrolysis temperature is 700 ℃.
After the average value of three parallel samples of the biochar prepared by the embodiment is obtained, the adsorption capacity of Cd (II) is 32.01mg/g, the adsorption removal rate is 63.89%, and the pH value of the biochar is 11.11.
Comparative example: under the same conditions, the Cd (II) adsorption capacity of 100 percent biogas residue biochar is 22.34mg/g, and the adsorption removal rate is 43.78 percent.
EXAMPLE 14 preparation of biochar
Experiments were performed according to the preparation method, test method, and calculation method of example 3.
Wherein the weight of the pyrolysis residue is 3g, the weight of the biogas residue is 7g, the co-pyrolysis time is 90min, and the co-pyrolysis temperature is 700 ℃.
After the average values of three parallel samples of the biochar prepared by the embodiment are obtained, the adsorption capacity of Cd (II) is 34.09mg/g, the adsorption removal rate is 67.43%, and the pH value of the biochar is 11.2.
Comparative example: under the same conditions, the Cd (II) adsorption capacity of 100 percent biogas residue biochar is 13.44mg/g, and the adsorption removal rate is 25.70 percent.
Example 15 preparation of biochar
Experiments were performed according to the preparation method, test method and calculation method of example 3.
Wherein the weight of the pyrolysis slag is 3g, the weight of the biogas slag is 7g, the co-pyrolysis time is 120min, and the co-pyrolysis temperature is 700 ℃.
After the average value of three parallel samples of the biochar prepared by the embodiment is obtained, the adsorption capacity of Cd (II) is 47.19mg/g, the adsorption removal rate is 94.31%, and the pH value of the biochar is 11.31.
Comparative example: under the same condition, the Cd (II) adsorption capacity of 100% biogas residue biochar is 9.36mg/g, and the adsorption removal rate is 24.28%.
EXAMPLE 16 preparation of biochar
Experiments were performed according to the preparation method, test method and calculation method of example 3.
Wherein the weight of the pyrolysis slag is 5g, the weight of the biogas residue is 5g, the co-pyrolysis time is 120min, and the co-pyrolysis temperature is 700 ℃.
After the average value of three parallel samples of the biochar prepared by the embodiment is obtained, the adsorption capacity of Cd (II) is 48.85mg/g, the adsorption removal rate is 97.33%, and the pH value of the biochar is 11.44.
Comparative example: under the same conditions, the adsorption capacity of Cd (II) of 100 percent biogas residue biochar is 9.36mg/g and the adsorption removal rate is 24.28 percent.
The method of the invention has no special limitation on the biogas residues and the oil-based rock debris, such as no special requirements on sources, components and the like. In order to verify that biogas residues and pyrolysis residues from different sources can be suitable for the technical scheme, the biogas residues and the pyrolysis residues from different sources are adopted, and the components and the component contents of the biogas residues and the pyrolysis residues are different greatly and are not completely the same. Therefore, the prepared biochar has certain difference on parameters such as Cd (II) adsorption capacity and the like, but any source and component can be applied to the method for treating the oil-based rock debris to obtain the biochar with more excellent performance compared with the biogas residue carbon.

Claims (10)

1. A method of treating oil-based cuttings, comprising: adding biogas residue.
2. The method of treating oil-based cuttings of claim 1, wherein: adding biogas residues, and performing co-pyrolysis to obtain the biochar.
3. The method of treating oil-based cuttings of claim 1 or 2, wherein: converting the oil-based rock debris into oil-based rock debris pyrolysis slag before adding the biogas residue, and then adding the biogas residue;
further, the method for converting the oil-based rock debris into the oil-based rock debris pyrolytic slag comprises the following steps: and pyrolyzing the oil-based rock debris at 400-600 ℃ to obtain solid residues.
4. A method of treating oil-based cuttings according to any of claims 1 to 3, wherein: the additive amount of the biogas residues is as follows: 50-100% (w/w), and the biogas residue is not equal to 100% (w/w); preferably, the addition amount of the biogas residues is 50-95% (w/w), 50-90% (w/w), 50-70% (w/w) and 70-90% (w/w).
5. The method of treating oil-based cuttings according to claim 3 or 4, comprising the steps of:
A. uniformly mixing the oil-based detritus pyrolysis residue and the biogas residue in proportion to obtain co-pyrolysis residue;
B. putting the co-decomposition slag in a closed container, and keeping inert atmosphere;
C. and (4) heating to the co-decomposition temperature, maintaining the constant temperature, and cooling to obtain the biochar.
6. The method of treating oil-based cuttings of claim 5, wherein:
in the step B, the inert atmosphere may be an atmosphere selected from an atmosphere containing nitrogen and/or other gases inert to the oil-based detritus pyrolysis residue and biogas residue, such as one or more of helium and neon;
in the step C, the cohydrolysis temperature is 400-700 ℃; the constant temperature is maintained for 60-120 min.
7. Biochar, which is prepared by the method of any one of claims 2 to 6.
8. A cadmium removal composition comprising the biochar of claim 7.
9. A method for adsorbing cadmium, which comprises the step of contacting the cadmium-containing medium with the biochar prepared by the method of any one of claims 2-6.
10. Use of the biochar prepared by the method of any one of claims 2-6 in cadmium removal.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102267695A (en) * 2011-07-25 2011-12-07 中国石油天然气集团公司 Method for preparing super activated charcoal from oily sludge
CN106512945A (en) * 2016-12-08 2017-03-22 东南大学 Preparation method of biochar capable of efficiently removing cadmium in solution
CN108773840A (en) * 2018-06-07 2018-11-09 广西壮族自治区环境保护科学研究院 A kind of method that destructive distillation oily sludge prepares charcoal
CN111377429A (en) * 2020-04-03 2020-07-07 中国环境科学研究院 Biochar prepared by pyrolyzing organic waste biogas residues and recycling method
CN113797891A (en) * 2020-12-11 2021-12-17 北京大学深圳研究生院 Biogas residue-based biochar material and preparation method and application thereof

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102267695A (en) * 2011-07-25 2011-12-07 中国石油天然气集团公司 Method for preparing super activated charcoal from oily sludge
CN106512945A (en) * 2016-12-08 2017-03-22 东南大学 Preparation method of biochar capable of efficiently removing cadmium in solution
CN108773840A (en) * 2018-06-07 2018-11-09 广西壮族自治区环境保护科学研究院 A kind of method that destructive distillation oily sludge prepares charcoal
CN111377429A (en) * 2020-04-03 2020-07-07 中国环境科学研究院 Biochar prepared by pyrolyzing organic waste biogas residues and recycling method
CN113797891A (en) * 2020-12-11 2021-12-17 北京大学深圳研究生院 Biogas residue-based biochar material and preparation method and application thereof

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
HANG YANG ET AL.: "Study on the co-pyrolysis characteristics of oil-based drill cuttings and lees", 《BIOMASS AND BIOENERGY》 *
黄训荣等: "改性粉煤灰对废水中镉的吸附作用", 《应用生态学报》 *

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