Abstract: An ammonia synthesis system and a control method thereof are provided. The ammonia synthesis system includes a hydrogen supply device, where a fluctuating amount of hydrogen is provided by the hydrogen supply device; a hydrogen storage container configured to store the hydrogen provided by the hydrogen supply device; and a nitrogen supply device configured to communicate with the hydrogen storage container to introduce nitrogen into the hydrogen storage container to maintain a stable pressure in the hydrogen storage container. The nitrogen supply device is able to introduce nitrogen into the hydrogen storage container, thus the amount of hydrogen provided is stable; in addition, the ammonia synthesis system can not only meet requirements of application scenarios where synthesis gas is produced from conventional raw material, but also be well applied to application scenarios where hydrogen for ammonia synthesis is obtained from hydrogen generation by green electricity.

Abstract: The present invention provides a multi plate screw press sludge dewatering machine and a helical shaft thereof. The multi plate screw press sludge dewatering machine includes fixed rings, movable rings, the helical shaft, a sludge inlet tank and a sludge discharging tank; the helical shaft adopts a variable diameter variable pitch helical shaft, a lead angle arrangement sequence of a helical blade of the whole helical shaft is gradual reduction from the sludge discharging tank to the sludge inlet tank, and the lead angle arrangement sequence is gradually reduced from 16°-22° to 6°-14°; a pitch of the helical shaft is gradually increased along a direction from the sludge inlet tank to the sludge discharging tank; a diameter of a shaft body of the helical shaft is gradually increased along with a direction of the sludge discharging tank from a ? position of a shaft length; and blockage prevention plates are arranged on two sides of the bottom of the helical blade.

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: The present invention provides a multi plate screw press sludge dewatering machine and a helical shaft thereof. The multi plate screw press sludge dewatering machine includes fixed rings, movable rings, the helical shaft, a sludge inlet tank and a sludge discharging tank; the helical shaft adopts a variable diameter variable pitch helical shaft, a lead angle arrangement sequence of a helical blade of the whole helical shaft is gradual reduction from the sludge discharging tank to the sludge inlet tank, and the lead angle arrangement sequence is gradually reduced from 16°-22° to 6°-14°; a pitch of the helical shaft is gradually increased along a direction from the sludge inlet tank to the sludge discharging tank; a diameter of a shaft body of the helical shaft is gradually increased along with a direction of the sludge discharging tank from a ? position of a shaft length; and blockage prevention plates are arranged on two sides of the bottom of the helical blade.

Abstract: The present invention provides a multi plate screw press sludge dewatering machine and a helical shaft thereof. The multi plate screw press sludge dewatering machine includes fixed rings, movable rings, the helical shaft, a sludge inlet tank and a sludge discharging tank; the helical shaft adopts a variable diameter variable pitch helical shaft, a lead angle arrangement sequence of a helical blade of the whole helical shaft is gradual reduction from the sludge discharging tank to the sludge inlet tank, and the lead angle arrangement sequence is gradually reduced from 16°-22° to 6°-14°; a pitch of the helical shaft is gradually increased along a direction from the sludge inlet tank to the sludge discharging tank; a diameter of a shaft body of the helical shaft is gradually increased along with a direction of the sludge discharging tank from a ? position of a shaft length; and blockage prevention plates are arranged on two sides of the bottom of the helical blade.

Abstract: The present invention provides a multi plate screw press sludge dewatering machine and a helical shaft thereof. The multi plate screw press sludge dewatering machine includes fixed rings, movable rings, the helical shaft, a sludge inlet tank and a sludge discharging tank; the helical shaft adopts a variable diameter variable pitch helical shaft, a lead angle arrangement sequence of a helical blade of the whole helical shaft is gradual reduction from the sludge discharging tank to the sludge inlet tank, and the lead angle arrangement sequence is gradually reduced from 16°-22° to 6°-14°; a pitch of the helical shaft is gradually increased along a direction from the sludge inlet tank to the sludge discharging tank; a diameter of a shaft body of the helical shaft is gradually increased along with a direction of the sludge discharging tank from a ? position of a shaft length; and blockage prevention plates are arranged on two sides of the bottom of the helical blade.