I. purpose and significance

Supercritical fluid extraction technology is an advanced separation and extraction technology in the world, which has aroused great interest of researchers all over the world in recent decades. In the fields of medicine, chemical industry, food, petroleum, environmental protection and cosmetics, a number of valuable topics have been completed, and a new industry has been formed worldwide. The development and use of supercritical fluid extraction technology to achieve large-scale industrial production is a major breakthrough for Chinese researchers to transform dozens or hundreds of research achievements that have been developed in the laboratory into productive forces and economic benefits.

Ii. Overview of domestic and foreign development

Supercritical fluid has a special solubility and was discovered by americans in the late 19th century. It was not until the 1970s that germans applied the craft of beer to industrial applications such as extracting beer. In the 1980s, China and Japan started at the same time, and now Japan's industrial application is at the world level. China started in the 1980s, and many scientific research institutes and institutes have made great efforts to explore and practice. For example: capsicum red pigment, angelica oil, garlic oil, red pigment of seaweed, Chinese prickly ash oil, lecithin and so on no less than a few hundred, but mostly in the laboratory results. At present, there are several domestic manufacturers capable of producing supercritical equipment (from one liter to two hundred liters), which can only satisfy the extraction of laboratory and some relatively expensive products. However, from the current domestic research results and demands, it is far from enough to meet the needs of large-scale industrial production.

Third, why should China industrialize in the field of supercritical extraction

China is a country rich in natural resources of animals and plants, with many resource varieties and quantities ranking top in the world. Natural pigments, essence and cosmetics are all precious resources that human beings rely on to survive and thrive. Due to the backward deep processing technology in China, especially in some economically underdeveloped regions, many precious natural resources are wasted in vain or exported as raw materials at a low price, and then sold back to China at a high price after the overseas deep processing, such as beer industry, tea industry, pigment essence and so on. The comprehensive utilization of all kinds of wastes such as fruit peels and cores, as well as the integration of western herbal medicine with international herbal medicine market, are in urgent need of large supercritical extraction equipment, which will turn cheap natural resources in poor areas into high value-added green products.

The obstacles to industrialization

At present due to the processing technology of the large domestic extraction kettle is more difficult, small volume production by supercritical fluid extraction equipment, for some quality lighter material extraction has high cost, the cost is high, processing capacity is weak, etc, from the research results show that the domestic equipment can not meet the requirements of many industries of industrialized production, and domestic need large industrial extraction equipment should be in the hundreds of above, the introduction of large equipment, its price is very expensive. This impedes the wide application of supercritical extraction technology in China. Meanwhile, the standardization of equipment and the safety of supporting equipment are the urgent problems to be solved at present. After three years of efforts, we finally succeeded in developing the large supercritical extraction equipment, which can meet the requirements of extraction technology regardless of pressure, temperature and flow, and cost only 30% of the imported equipment. It has reasonable structure, superior performance and meets the hygiene conditions of the food industry. At the same time, its technical indicators such as temperature sensing, anti-fatigue dynamic strength, sealing performance and safety coefficient are better than those of similar domestic and foreign equipment. The products are: angelica oil, alone live oil, purple red pigment, changbai mountain forest frog seed oil, sea rainbow oil, ginseng oil, ginseng oil, red flower oil, hops oil, garlic oil, ginger oil, aloe, kunming pyrethrum and dozens of varieties, and can also remove 80% of pesticide residues from ginseng powder.

The research on foaming PP in China started in the late 1970s. Sinopec Beijing chemical research institute undertook the national "ninth five-year" project to develop a new modified PP resin with high melt strength, but it has not yet been industrialized in China.

At present, the industrialization of PP foaming products is still blank in China, and many domestic manufacturers are trying to develop it. However, due to the weak accumulation of research on polypropylene raw materials and foaming process, industrial development is quite difficult, and now they mainly rely on imports to obtain special foaming polypropylene materials.

It can be predicted that the active development and application of polypropylene foaming materials will be of great significance to the development of domestic synthetic resin industry, the expansion of the application field of polypropylene foaming materials and the development of automobile, packaging, food and environmental protection. Articles come from the Internet

Supercritical foaming equipment