Upper part of the horizontal leaching workshop

What are the good methods to reduce losses in the horizontal leaching workshop?

Today, Kaifeng Boda will explain to you two methods to reduce solvent loss in the leaching workshop

(1) Improve the concentration of mixed oil and master the solvent ratio
It is necessary to choose an appropriate solvent ratio reasonably. A high solvent ratio has a certain effect on reducing residual oil in the meal, but the received mixed oil concentration is too low, which will increase the load on the recovery system and easily cause solubility in the crude oil. Generally, based on the oil content of the raw material, the concentration of the mixed oil is increased by 5% to 10% on this basis. In actual production, the solvent dosage is generally 0.6:1 (spray leaching) while ensuring an increase in the concentration of residual oil and mixed oil in the meal. The spraying method adopts the counter current method of solvent or mixed oil and embryo, that is, the material just entering the extractor is sprayed with a lower concentration of mixed oil, which can obtain a thicker mixed oil. The commonly used rotary extractor in oil factories has a solvent ratio of 0.8-1.1:1 during leaching, and also uses a counter current method.
(2) Master the main evaporation elements in evaporation
The evaporation temperature under normal pressure is 75-80 ℃ for evaporator 1, and the indirect steam pressure is 0.2-0.3 MPa; Evaporator 2 # operates at 95-115 ℃ with an indirect steam pressure of 0.3-0.4 MPa; The stripping tower is at around 125 ℃, with an indirect steam pressure of 0.4 MPa and a direct steam pressure of 0.05 MPa.
Direct steam with high water content and large usage can cause flooding of the stripping tower and excessive solvent content in the crude oil; A steam water separator can be added or direct steam can be heated into superheated direct steam to improve steam quality and reduce liquid flooding in the stripping tower. The evaporation rate must be uniform and not fluctuate too much or too little, otherwise it will cause liquid flooding in the 1 # and 2 # evaporators and incomplete stripping of the stripping tower, resulting in unstable residual oil dissolution and even exceeding the standard. The amount of direct steam used is 0.3~1.4 times that of the mixed oil. The concentration of the mixed oil should be regularly measured to continuously improve the concentration of the mixed oil. The liquid level height of the mixed oil during evaporation (referring to the control of the balance cylinder) should be at 1/4 of the height of the evaporator long tube.

Combining the above two methods, I believe everyone will have a certain understanding of the methods when using the upper part of the rotary leaching workshop.

1. The horizontal leaching equipment adopts the advanced fixed grid plate leaching device currently available internationally, with a wide range of applications, easy operation and management, one-time production and installation ready, and no maintenance required during use. Due to the use of fixed stainless steel for the grating, it has the characteristics of corrosion resistance and abrasion resistance, and has a long service life. Overcoming the drawbacks of heavy maintenance workload and high maintenance costs. The leaching effect is good, and the fixed grid plate extractor can push the material forward, allowing the material to receive uniform soaking in a flipped state. The solvent permeability is good, which can reduce residual oil in the meal by 0.5%. The fixed grid plate extractor keeps the materials in constant relative motion during the production process, so it is not easy for the materials to form a "bridging" phenomenon, which is convenient for operation and conducive to the smooth connection of the upper and lower processes. At the same time, due to the use of trapezoidal grate bars for fixed arrangement, the grating itself has self-cleaning characteristics and there will be no blockage of the grating. And the material does not vibrate, purifying the production workshop environment. Good draining effect, designing corresponding grid density and matching different gaps between soaking and draining sections according to different materials is conducive to the formation of soaking liquid level and draining effect, and helps to reduce the load of the evaporator.
The siphon spray device used in the horizontal leaching equipment has good process performance and uniform and stable intermittent spray speed, which can improve the spray quality and minimize the residual oil in the meal.
3. The flat rotation leaching equipment adopts a new process of solvent oil secondary circulation and oil hopper mixed oil overflow in stages for leaching spraying. This process is equivalent to increasing the solvent spray volume, washing frequency and time without increasing the solvent ratio, improving the concentration of mixed oil, and effectively ensuring the residual oil index in the meal. Practice has proven that adopting the new process of secondary spraying is also beneficial in reducing the load on the evaporation and condensation recovery system, ensuring further reduction in dissolution and steam consumption.
4. The speed of the frequency conversion and variable speed device of the leaching equipment can be freely adjusted according to different materials, required production and process effects, making it simple and reliable.
5. The design capacity and material layer height of the leaching device in the rotary leaching equipment are large, with a yield margin of generally 20-40%, which is conducive to improving yield and increasing efficiency.