Mechanical continuous extraction process for stevioside and continuous extraction unit

Abstract

The invention discloses a mechanical continuous extraction process for stevioside and a continuous extraction unit. The continuous extraction process comprises the following steps of: 1, saturated imbibition immersion; 2, carrying out mechanical continuous extraction by adopting the continuous extraction unit; 3, post-recycling treatment; and 4, follow-up treatment. The continuous extraction unitcomprises a shell, a high-voltage kneading and tearing device and a low-voltage expanding imbibition device which are arranged inside the shell; both the high-voltage kneading and tearing device and the low-voltage expanding imbibition device comprise horizontal thrusters; the horizontal thrusters are of twin-screw extruders and comprise propelling main shafts and propelling countershafts which are synchronous in the rotation and opposite in the rotation direction; and helical blades, which are opposite in the helical direction, are arranged on the propelling main shafts and the propelling countershafts. The process and the continuous extraction unit have the advantages of reasonable design, convenience for implementation, energy saving, environment friendliness, little water consumption,high production efficiency, high extraction efficiency and capability of effectively solving the practical problems, such as larger water consumption, great waste water handling capacity, high investment cost, low production efficiency, low extraction rate and the like when the traditional pot-type steeping tank is used for extraction.

Description

technical field [0001] The invention belongs to the technical field of extraction of sweet components of stevia rebaudiana, and in particular relates to a mechanical continuous extraction process of stevioside and a continuous extraction unit. Background technique [0002] my country's stevia production accounts for more than 85% of the world's share, but the initial process of stevia production is also the key process of soaking and extracting stevia leaves, which has been using traditional extraction tank equipment. Although there are also optimized so-called three-stage countercurrent extraction processes for the tank extraction process, ultrasonic or microwave-assisted enhancement, but after all, it has not jumped out of the traditional process category of long cycle, low efficiency, large solid-liquid ratio, and large amount of wastewater polluting the environment. [0003] The extraction of the sweetness components of stevia is mainly the extraction of stevia, the puri...

AI Technical Summary

Problems solved by technology

But the cold immersion and hot immersion processes of horizontal tank and vertical tank all have common defect: (1) water consumption is big, and blowdown is big: the solid-liquid ratio of general tank type immersion is all in 1: 12 to 1: 22. Large water consumption; (2) Energy consumption: due to the large amount of material to be processed, the energy consumption is also large; (3) Low efficiency: Generally speaking, a soaking cycle takes more than 2 hours, and multiple leaching is required, so the production efficiency is low; (4) Large floor area: From material crushing, feeding, soaking, discharging, recycling and other processes, the assembly line is long, so the floor area is also large; (5) The extraction is not thorough: the traditional soaking process uses soaking tanks

However, the disadvantage of mechanical crushing is high energy consumption, which can account for 50% to 60% of the total energy consumption of the process, and the cost is very high

Images