Centrifugal wet processing machinery The main difference between it and the general wet processing machinery is that centrifuges are used instead of presses, and centrifugal wet fish powder processing machinery is used as a heating medium with gas produced by a fuel furnace. The main equipment includes: 1. Horizontal spiral centrifuge(also known as dump machine). It consists of a horizontal drum and a central spiral transmitter with one end cylindrical and the other end conical. They use the same turn for high-speed rotation, with differential reducer connection, there is a certain speed difference. After the shredded cooked fish pulp enters the drum, under the effect of centrifugal force, the fish slag is heavily concentrated and sinks on the inner wall of the drum and is sent out by the spiral transmitter. The proportion of juice and fish oil is small. Under the side pressure of centrifugal force, it is discharged from the overflow port at the other end of the drum. 2 Multi-tube steamer(desiccant).
It consists of a fixed shell and a cylinder that rotates slowly within it. There are many longitudinal air pipes in the cylinder, and gas is used as a heating medium in the tube. After the material enters the cylinder, due to the rotation of the cylinder, it is turned between the air pipes, cooked or dried. This machine has strong adaptability to raw materials, and the resulting fish powder has a low oil content and is suitable for use on board. However, when recycling juice to make whole fish powder, two heating systems are required because the heating medium used by the evaporator is steam. For this reason, some centrifugal fishmeal machines still use steam as a heating medium, and the vaporizers and dryers used are the same as the normal wet machinery. In recent years, a vertical fast steamer has emerged, which is suitable for the production of centrifugal fishmeal using steam as a heating medium. It consists of an upright cylinder with a steam jacket and a central shaft. There are 2 to 4 active scrapers on the shaft. When the shaft rotates, the scraper moves closely to the inner wall of the cylinder by the effect of centrifugal force. It not only stirs the material, but also continuously scraws the inner wall of the cylinder to prevent the material from sticking to the wall. It is characterized by high heat transfer efficiency and fast cooking speed.
In addition, some large trawlers or small fishmeal machines installed on board processing bases can process fishmeal directly at sea. This kind of machinery is generally not equipped with a recovery juice concentrate, and more three-dimensional assembly is used to save space. It is called an assembly fishmeal processing machine.
The quality of fish oil and fishmeal obtained by mechanical processing by wet method is good, and heat energy can be saved when using multi-effect evaporators. Therefore, it is adopted by most processing enterprises in the world.
The exhaust gas discharged during the processing of fishmeal equipment is generally discharged into the atmosphere through deodorizing devices. The commonly used deodorizing method is the water burning method, and the main equipment used is the deodorizing water tower. It is a filler tower, the lower part has exhaust gas inlet, the upper part has cold water inlet and sprinkler device, and the middle is the filler layer. When the exhaust gas enters the tower and rises through the packing layer, it encounters cold water sprayed from the above layer. Both of them are fully exposed to the heat transfer in the packing layer. The steam contained in the exhaust gas is condensed, and part of the water-soluble odor material is removed at the same time. The remaining insoluble odors and non-condensing gases are sent to boilers or special combustion furnaces for oxidation and decomposition into odorless substances.
Prospects Since the 1960s, fishmeal processing machinery has developed in the direction of large-scale, serialization, automation, energy conservation, and pollution prevention. Equipment for processing 300 tons per day of raw materials is now common. In order to save energy, some fishmeal machines add heat exchangers and preheat intermediate products using residual heat; In some fishmeal machines, the entire system is sealed, and the gas discharged from each equipment is treated with a deodorant device to reduce environmental pollution.