Patent ID: 11939238
Assignee: DALIAN UNIVERSITY OF TECHNOLOGY
Field: Environmental technology (Chemistry)
Classification: CPC C  Y | IPC C

Claim 7:
8. A method for hydrate-based wastewater treatment and cold storage using the apparatus according to claim 1, comprising the following steps:
cold storage and wastewater treatment stage: the solid-liquid separation switch being in a closed state, wastewater flowing from the wastewater tank into the inner tank of the wastewater treatment and cold storage tank through a tenth one-way valve, the water chilling unit providing the secondary refrigerant at a low temperature, and the secondary refrigerant being conveyed by the first solution pump to the wastewater treatment and cold storage tank through the first flow meter, the first one-way valve, and the second two-way valve, and exchanging heat with a mixture of the hydrate former and the wastewater through the evaporator coil for a heat exchange, so that a hydrate is formed and the wastewater is concentrated to obtain concentrated wastewater; after the heat exchange being completed, the secondary refrigerant flowing back to the water chilling unit through the first two-way valve, the fourth one-way valve, and the second flow meter, and being cooled again to complete a wastewater treatment and cold storage cycle; after the wastewater treatment and cold storage cycle starting, the second air pump conveying air outside the apparatus into the gas generator for continuous airflow disturbance in the inner tank of the wastewater treatment and cold storage tank, and the air being discharged from the two-way air valve after the continuous airflow disturbance being completed; the system monitoring device monitoring a temperature change before and after heat absorption of the secondary refrigerant and a temperature change in a working medium for the hydrate-based wastewater treatment and cold storage and the wastewater treatment and cold storage tank in real time;
wastewater separation stage: the water chilling unit continuing to operate, the solid-liquid separation switch being raised, the concentrated wastewater flowing into the air thermal insulation layer through the filter screen disc, the fifth one-way valve being opened after wastewater separation being completed, and the fifth one-way valve being closed after the concentrated wastewater being discharged through the concentrated wastewater discharge pipe; after the wastewater separation stage starting, the two-way air valve, the first air pump, and the third solution pump being opened, and air flowing from an outside into the inner tank of the wastewater treatment and cold storage tank through the two-way air valve, entering the air thermal insulation layer through the solid-liquid separation switch, and then being discharged through the first air pump, to complete a suction filtration cycle, and improve a solid-liquid separation efficiency; purified water in the return tank being pumped into the spraying device through the third solution pump for a washing operation to improve a pollutant removal efficiency, during which the ninth one-way valve and the eighth one-way valve being closed; after the suction filtration cycle and the washing operation being completed, the two-way air valve, the first air pump, and the third solution pump being closed, and the solid-liquid separation switch being lowered to be closed;
hydrate decomposition stage: the secondary refrigerant in the wastewater treatment and cold storage tank being pumped by the second solution pump to the finned tube heat exchanger through the second two-way valve and the second one-way valve, fully absorbing heat in the finned tube heat exchanger through the heat exchange system, then flowing back to the wastewater treatment and cold storage tank through the third one-way valve and the first two-way valve, and being cooled through a heat exchange with the hydrate at a low temperature in the evaporator coil to complete a heat exchange cycle; and
water recovery stage: after the hydrate being completely decomposed, the water layer positioning device positioning a contact surface between the hydrate former and the purified water, a length of the telescopic pipe being changed to a liquid surface separation position between the hydrate former and the purified water, the fourth solution pump being turned on, the purified water being drawn into the return tank and then flowing out of the apparatus from a treated water discharge pipe, during which the seventh one-way valve being closed, and after the purified water being completely recovered, a remaining part of the purified water being stored in the return tank for use in a next washing.