Oil refining plant

Automation controlled by the computers

Waste plastic to oil refining equipment

Writer:Nengxing    time:16/12/2020


Waste plastic oil refining equipment


Use waste plastics to refine oil directly, without cleaning or sorting. It can not only avoid pollution, but also bring economic benefits.


Ⅰ. The prospect of project development

  With the rapid development of the plastics industry, the application of plastic products has become more and more widespread. The large-scale application of plastics 

  has brought many conveniences to people's lives, but also caused many problems. It is difficult to decompose in the natural environment, and a large amount of waste 

  has caused serious environmental pollution. At present, the main treatment methods of plastic waste are landfill, incineration, and recycling of waste plastics. 

  However, both landfill and incineration will cause secondary pollution, but the scope of recycling of waste plastics is very limited. For example, domestic waste 

  plastics and industrial waste plastics “go with the wind” from paper mills cannot be recycled. With the continuous rise of international crude oil prices, the use 

  of waste plastics to refine fuel oil has attracted the attention of all countries in the world. Waste plastic refining can avoid the pollution of waste plastics to 

  the environment and bring certain economic benefits.


Ⅱ. Scope of raw materials

  Industrial and domestic waste---waste plastic; waste plastic sources include plastic film (including plastic packaging bags and agricultural film), plastic wire and 

  woven products, foam plastic products, plastic packaging boxes and containers, cable coating materials, and various Daily-use plastic products such as sundries, 

  sports and entertainment, health care, etc. Among them, plastic products such as films, foams, boxes and containers, weaving, and sheets are mainly used for plastic 

  packaging. In addition, some other plastic packaging products (such as plastic pallets), agricultural plastic products (such as agricultural plastic water-saving 

  equipment), and plastic products for decoration have a higher scrap rate. 

  Plastic packaging, televisions, washing machines, refrigerators, and electronic communication equipment such as computers, mobile phones, VCDs, DVDs, records, CDs, 

  etc. have accelerated their replacement rates, and the number of scrapped products has risen sharply each year, causing serious environmental problems. Plastics are an

  important part of home appliances. The amount of renewable plastics generated every year is at least 150,000 tons. If you take into account the amount of renewable 

  plastics used in scrapped electronic communication equipment, the figure is about 200,000 tons. The amount of plastic parts used in electronic appliances has reached 

  more than 1 million tons, and they are widely used in industrial supporting, information, transportation, aerospace and other fields, and the products are updated 

  quickly. As these products gradually enter a large number of scrapped periods, they have become an important source of waste plastics.


Ⅲ Three waste discharge

Waste residue:

After the waste plastic is cracked by catalytic thermal, one is to form a solid residue, which accounts for about 5% to 10% of the weight of the waste plastic. Its main 

component is crude carbon black. It can be used as a raw material for the production of industrial carbon black, and it can also be mixed with fly ash produced by 

coal-fired power plants as a raw material for making fly ash bricks (an environmentally friendly building material). Due to the pollution of the environment when 

discharging 

ash and slag, we have adopted national patented slagging technology. One is to form crude asphalt, which can be used for road paving or as a waterproof material.

Waste water:

In the entire production process, only the condenser and the cooler use water, and it plays a cooling role and can be recycled. Because 1 ton only produces 50 kg of waste water in the water seal, the volume is small and easy to handle, and the special flue heat can be used Perform neutralization treatment.

Exhaust gas: 

In the process of refining fuel oil from waste plastics, there are some combustible gases that cannot be liquefied at normal temperature and normal pressure, and if they are directly discharged, they may cause air pollution. The medium-pressure exhaust gas burner independently developed by our company has effectively solved this problem. The exhaust gas passes through two safety devices, the water seal and the anti-back fire device, and is fully burned at the bottom of the furnace through the normal 

pressure environmentally friendly burner. On the one hand, it can prevent air pollution, on the other hand, it can save a lot of fuel.


Ⅳ The latest catalytic cracking and oil refining technology

Waste plastics are usually recycled by pyrolysis and oilification technology, which means that waste plastics are decomposed by heating or catalysis to obtain polymerized monomers, diesel, gasoline, fuel oil and gas, asphalt, etc. The pyrolysis of waste plastics for oil refining is not only pollution-free to the environment, but also can 

effectively recover energy. It can be said that the pyrolysis of waste plastics for oil refining is the opposite process of manufacturing plastic products in the chemical industry using petroleum as raw materials. According to the different components of waste plastics, our company adopts a special reverse process fractionation tower to 

replace the catalyst, so as to increase the reaction speed and reduce the reaction conditions. Compared with domestic pyrolysis oil chemical production, it has increased oil yield and improved oil quality.


Different raw materials, different cracking behavior

Due to the different composition of waste plastics, their cracking behavior is also different. Polyethylene (PE), polypropylene (PP) and polystyrene (PS) are almost all 

decomposed between 300-400°C. It releases HCL at a lower temperature first and produces polyhydrocarbons, and then further decomposes at a higher temperature. Because 

HCL is corrosive to equipment, it also affects the service life of cracking catalyst and the quality of diesel and gasoline. Therefore, it is generally required that the content of PVC waste plastics in cracking raw materials does not exceed 30%.


Catalytic and pyrolyzing products

Different plastics have very different molecular structures, so the composition and recovery rate of catalytic pyrolysis products are also different.

Generally, taking PE/PP as an example, thermal decomposition produces four types of products:


a. Hydrocarbon gases (C1-C4) account for 6%,

b. Oil products (gasoline carbon molecules are C5-C11, diesel carbon molecules are C12-C20, heavy oil carbon molecules are C20) account for 80%,

c. Asphalt accounts for 10%

d. Water accounts for 4%