Abstract: The present disclosure discloses a method and system for determining biochar identity and an electronic device. The method includes: inputting physical and chemical property data of a sample to be identified into a biochar identity determination model to obtain identity information of the sample, where a process for determining the biochar identity determination model includes the following steps: performing abnormality detection and standardization processing on the input variable data matrix, and constructing a feature data matrix based on a processed input variable data matrix; and obtaining a random subspace nearest neighbor clustering ensemble learning classifier based on the feature data matrix, a sample identity multi-category label column vector and a random subspace nearest neighbor clustering ensemble learning algorithm, where the random subspace nearest neighbor clustering ensemble learning classifier is the biochar identity determination model.

Abstract: A one-step method for preparing a magnetic magnesium-iron layered double hydroxide (LDH)-biochar composite material and use thereof provided. Biomass, as a substrate, is placed in a ferric salt solution, magnesium hydroxide is added, the materials are fully stirred and aged for a certain time, the aged materials are dried to obtain a magnesium-iron LDH-biomass, and the magnetic magnesium-iron LDH-biochar composite material is obtained after pyrolysis. The method solves problems of uncontrollable reaction and low crystallinity of products in preparing LDH using a coprecipitation method, reduces the amount of drugs, omits a step of adjusting a pH with an alkaline solution, improves yield and reduces a cost. The obtained magnetic magnesium-iron LDH-biochar composite material exhibits an excellent performance in adsorbing phosphate in water and can be recovered by an external magnetic field. Thus, an important method is provided for preparing LDH and the composite thereof.

Abstract: A preparation method of charcoal-based fertilizer is provided. Particularly, a special pig manure charcoal modified by amino grafting, a preparation method thereof, and its application in the reuse of nitrogen from farmland drainage are provided. The preparation method includes the following steps: 1) drying raw pig manure to a moisture content of 80%-85% and carrying out pickling, drying, and crushing successively to obtain a dried pig manure powder; 2) conducting liquid nitrogen pretreatment and high-temperature charcoalization to obtain an expanded pig manure charcoal; 3) performing carboxylation treatment to obtain a carboxylated pig manure charcoal; 4) amino grafting: adding an ammonia liquor to the carboxylated pig manure charcoal obtained in step 3), stirring for 20-24 h in an oil bath at 200-240° C.; washing and filtering; and drying and grinding to obtain the special pig manure charcoal modified by amino grafting.

Abstract: A preparation method of charcoal-based fertilizer is provided. Particularly, a special pig manure charcoal modified by amino grafting, a preparation method thereof, and its application in the reuse of nitrogen from farmland drainage are provided. The preparation method includes the following steps: 1) drying raw pig manure to a moisture content of 80%-85% and carrying out pickling, drying, and crushing successively to obtain a dried pig manure powder; 2) conducting liquid nitrogen pretreatment and high-temperature charcoalization to obtain an expanded pig manure charcoal; 3) performing carboxylation treatment to obtain a carboxylated pig manure charcoal; 4) amino grafting: adding an ammonia liquor to the carboxylated pig manure charcoal obtained in step 3), stirring for 20-24 h in an oil bath at 200-240° C.; washing and filtering; and drying and grinding to obtain the special pig manure charcoal modified by amino grafting.

Abstract: Disclosed is a method of preparing a carbon quantum dot from soybean dregs by hydrothermal synthesis, including: mixing the soybean dregs with water, and subjecting the reaction mixture under heating at 100-500° C. in an autoclave for reaction; cooling the reaction mixture when the reaction is completed, and removing insoluble substances from the reaction mixture; and dialyzing the reaction mixture, and lyophilizing the dialyzed product to produce the carbon quantum dot. The invention further provides the carbon quantum dot prepared by the above method and a use thereof in the detection of Fe3+ and Hg2+ in water, where the lowest detection limit can reach 30 nmol/L and the detection range is 0.1-50 ?mol/L.

Abstract: A high-concentration anaerobic fermentation apparatus includes a liquid accumulation tank, a fermentation vessel, a feeding assembly, and a biogas residue collecting bin. The feeding assembly includes a hopper and a return conveyor belt including a first portion extending downward from the hopper till below a liquid level, a second portion extending upward from a bottom end of the first portion till above the liquid level, a third portion extending downward from a top end of the second portion till the liquid level, and a fourth portion extending upward from a bottom end of the third portion till out of the liquid level and above the biogas residue collecting bin. A pressure-feed flange is disposed at an outer side of the fermentation vessel, a feed channel is formed between the pressure-feed flange and the first portion, and a discharge channel is formed between the pressure-feed flange and the fourth portion.

Abstract: A biomass gas-carbon co-production reactor includes: multiple downward bed pyrolysis zones, a gas-solid separation zone, an activated carbon activation zone, and a secondary pyrolysis reaction zone; wherein the activated carbon activation zone communicates with the gas-solid separation zone and the secondary pyrolysis reaction zone; tops of the downward bed pyrolysis zones penetrate through a top of the gas-solid separation zone, and a heat carrier inlet and a raw material inlet are symmetrically arranged on a left side and a right side of each of the downward bed pyrolysis zones; bottoms of the downward bed pyrolysis zones are located inside the secondary pyrolysis reaction zone for communicating; a fluidizing air inlet is provided at a bottom of the secondary pyrolysis reaction zone, and an activated gas inlet is provided at a top of the secondary pyrolysis reaction zone; an activated carbon outlet is provided on the gas-solid separation zone.

Abstract: Disclosed is a method of preparing a carbon quantum dot from soybean dregs by hydrothermal synthesis, including: mixing the soybean dregs with water, and subjecting the reaction mixture under heating at 100-500° C. in an autoclave for reaction; cooling the reaction mixture when the reaction is completed, and removing insoluble substances from the reaction mixture; and dialyzing the reaction mixture, and lyophilizing the dialyzed product to produce the carbon quantum dot. The invention further provides the carbon quantum dot prepared by the above method and a use thereof in the detection of Fe3+ and Hg2+ in water, where the lowest detection limit can reach 30 nmol/L and the detection range is 0.1-50 ?mol/L.

Abstract: A biomass gas-carbon co-production reactor includes: multiple downward bed pyrolysis zones, a gas-solid separation zone, an activated carbon activation zone, and a secondary pyrolysis reaction zone; Wherein the activated carbon activation zone communicates with the gas-solid separation zone and the secondary pyrolysis reaction zone; tops of the downward bed pyrolysis zones penetrate through a top of the gas-solid separation zone, and a heat carrier inlet and a raw material inlet are symmetrically arranged on a left side and a right side of each of the downward bed pyrolysis zones; bottoms of the downward bed pyrolysis zones are located inside the secondary pyrolysis reaction zone for communicating; a fluidizing air inlet is provided at a bottom of the secondary pyrolysis reaction zone, and an activated gas inlet is provided at a top of the secondary pyrolysis reaction zone; an activated carbon outlet is provided on the gas-solid separation zone.

Abstract: The present invention belongs to the field of feed, and particularly relates to a feed additive containing biogas residues for cows. The feed additive for cows is prepared by mixing the following components in parts by weight: 20-50 parts of biogas residues, 15-28 parts of radix astragali residues, 10-12 parts of apple pomace, 3-6 parts of purple perilla, 4-8 parts of eucommia leaves, 3-8 parts of purslane and 0-1 part of maca powder. The biogas residues are resulting products from anaerobic fermentation of distillers' grains left by using cassava or sweet potatoes as raw materials for fermentation, and are then moisture removed by mechanical extrusion, dried by exposure to the sun and finally crushed by a crusher for use. The scientifically-formulated and nutrient-rich feed additive provided by the present invention enhances the immunity of cows, decreases the risk of various diseases or infections during the feeding process, and reduces the use of drugs.

Abstract: The present invention belongs to the field of feed, and particularly relates to formula feed containing biogas residues for chickens. The formula feed for chickens is prepared by mixing a component A and a component B, wherein the component A makes up 17%-37.5% of the total weight. The component A is prepared by mixing the following raw materials in parts by weight: 20-50 parts of biogas residues, 15-28 parts of radix astragali residues, 3-6 parts of purple perilla, 4-8 parts of eucommia leaves, 3-8 parts of purslane and 1-2 parts of premix. The biogas residues are resulting products from anaerobic fermentation of distillers' grains left by using cassava or sweet potatoes as raw materials for fermentation, and are then moisture removed by mechanical extrusion, dried by exposure to the sun and finally crushed by a crusher for use. The component B is prepared by mixing the following raw materials in parts by weight: 48-52 parts of corn, 10-12 parts of soybean meal, 1.2-1.5 parts of calcium hydrophosphate, 1.