Please select the most similar patent number from A, B, C and D. Which number is?
A treatment method for implementing efficient resource utilisation of waste plastic (5), the treatment method comprising using high temperature liquid (4) to directly heat the waste plastic (5); the temperature of the high temperature liquid (4) needs to enable the waste plastic (5) to undergo a thermal cracking reaction in the high temperature liquid (4) to generate pyrolysis oil and slag. The high temperature liquid (4) may be a molten metal or metal alloy, or the high temperature liquid (4) may be a molten inorganic salt or inorganic base, or the high temperature liquid (4) may be a dual-layer liquid formed of a molten metal or metal alloy and a molten inorganic salt and/or inorganic base.
A: The present invention relates to a system and process of industrial continuous cracking of mixed waste plastics according to class, the system comprising: an extrusion dryer; first and second stage lifting screw conveyors; a catalytic mixing cylinder; a semi-plasticizing feeder; first, second and third stage cracking reaction furnaces; slag discharging first, second and third stage screws; a separator; a slag storage tank; first, second and third basket-type filters; first, second and third stage settling towers; air-cooling first, second and third heat exchangers; water-cooling first, second and third stage heat exchangers; first, second and third stage gas-liquid separation tanks; first, second and third oil tanks; a non-condensable combustible gas purifier; a tail gas treatment module; a combustion chamber; and a combustor. In the present invention, according to the characteristics of different types of plastic and different cracking temperatures, a method for cracking mixed plastics according to class is provided, and the economic value added of the product of cracking is increased by independently recycling a cracked oil product; in addition, energy consumption during the cracking process is reduced by means of the recycling combustion of non-condensable combustible gas and the recycling of high-temperature waste heat, and waste gas passes through multiple purification steps, thus preventing environmental pollution.
B: A liquid treatment device, a heat exchange device (4), a heat exchange box (10), a liquid heating appliance (20), a control method for the liquid heating appliance (20), a control device for the liquid heating appliance (20), and a computer-readable storage medium (90). The liquid treatment device comprises: a liquid inlet channel; a liquid outlet channel (32) and a heat exchange device (4); and a heating assembly. When outputting a liquid such as water having a relatively low temperature, the liquid treatment device can first heat the liquid such as water to a relatively high temperature by means of the heating assembly, so as to realize high-temperature sterilization, and then performs, by means of the heat exchange device (4), heat exchange to cool the liquid such as water which has been heated to a relatively high temperature to a temperature required by a user and then discharge same, so that a liquid such as water having a specified temperature can be outputted; in addition, performing high-temperature sterilization or disinfection on the liquid such as water which has a relatively low temperature before outputting same can remove bacteria and microorganisms in the liquid, thereby ensuring that the output low-temperature liquid is clean and sanitary.
C: A rare earth metal and a rare earth metal alloy and a method for the preparation of these by molten salt electrolysis. In the method, the electrolyte is an alkali metal or the chloride-fused salt of an alkaline earth metal, the positive electrode is an inert electrode or graphite, the negative electrode is composed of a rare-earth metal oxide or a rare-earth metal oxide and the oxides of other alloy components and/or metal powders, and electrolysis is induced by the passage of a direct current. During the electrolytic process, the temperature of electrolysis is higher than the melting point of the rare earth metal alloy or of the rare earth metal produced, and lower than the melting point of the negative electrode; the surface layer of the negative electrode is in the first stage electrolyzed to a liquid metal film which accumulates to a certain volume before falling to the crucible at the bottom. The current density of the negative electrode is sufficient to separate out from said negative electrode the components of the rare earth metal alloy or the rare earth metal. The electrolysis voltage is lower than the decomposition potential of the electrolyte and higher than the decomposition potential of the oxides corresponding to each component of the rare earth metal alloy or to the rare earth metal. The rare earth metal alloy or the rare earth metal obtained through the present method is in a liquid state and is collected in a crucible. The present method is technically simple and environmentally-friendly, while featuring low energy consumption, high current efficiency, and low costs.
D: An energy conserving sludge drying system comprising: a vacuum heating unit (10), an incineration unit (30), a vacuum cooling unit (20), and a molten-salt heat exchange unit (40). The vacuum cooling unit (20) comprises: a high-temperature gas inlet (202), a condensate outlet (203), a low-temperature gas outlet (204), a low-temperature liquid inlet (205), and an intermediate-temperature liquid outlet (206). The high-temperature gas inlet (202) of the vacuum cooling unit (20) communicates with the vacuum heating unit (10). The incineration unit (30) comprises: an incinerator (301), an incineration gas inlet (302), an oxidant gas inlet (305), a smoke discharging port (303), a cold molten-salt inlet (306), and a hot molten-salt outlet (307). The incineration gas inlet (302) communicates with the low-temperature gas outlet (204) of the vacuum cooling unit (20). The molten-salt heat exchange unit (40) comprises: a cold molten-salt outlet (402), a hot molten-salt inlet (403), an intermediate-temperature liquid inlet (404), and a high-temperature liquid outlet (405). The cold molten-salt outlet (402) communicates with the cold molten-salt inlet (306) of the incineration unit (30). The hot molten-salt inlet (403) communicates with the hot molten-salt outlet (307) of the incineration unit (30). The intermediate-temperature liquid inlet (404) communicates with the intermediate-temperature liquid outlet (206) of the vacuum cooling unit (20). The high-temperature liquid outlet (405) communicates with the vacuum heating unit (10).
Answer: A