Coke and semi coke

News 2020-11-27

Coke and semi coke

As a new type of carbon material, semi coke can replace coke and widely used in chemical, smelting, gas production and other industries after repeated trials and applications. It is used in the production of metallic magnesium, ferroalloy, ferrosilicon, silicomanganese, fertilizer, calcium carbide, etc. It has higher application value in improving the quality of downstream products, saving energy, reducing production costs, and increasing output. So what is the essential difference between semi coke and coke?

1.Different raw materials

Generally, the raw materials of coke products are mainly coking coals with strong cohesive properties, such as coking coal and fat coal, which are generally produced from a single coal, and no coal blending is required in the production process. Semi coke fired from high-quality Jurassic clean coal that is abundant in Shenfu coalfield. It’s a new type of carbon material.

2.Different technology

Generally, the technical production of coke products is mainly based on high-temperature dry distillation, and the dry distillation temperature usually needs to reach about 1000°C. After years of development, the current technology of large-scale coke oven equipment is relatively mature, and it has the conditions to increase the unit output of equipment to achieve large-scale production. The newly-built coke ovens in recent years have an output of about 500,000 tons per year, and the highest can even exceed 1 million tons per year. For example, the two 7.63-meter-high coking ovens of the coal international coking plant that have been put into operation recently can reach 1.1 million tons/year.

semi coke

The production of semi coke is mostly based on low-temperature dry distillation, and the dry distillation temperature is generally around 600 ℃. Due to the late start, the annual output of a single furnace of semi coke low-temperature dry distillation equipment is mostly around 30,000 tons/year, and 50,000 tons/year. The low-temperature retort furnace equipment of the forum over a year is still in the exploration and test stage, and the technology of large-scale equipment is still immature.

3.Different quality

Compared with common coke products, semi coke has the advantages of high fixed carbon, high specific resistivity, high chemical activity, low ash ingredient, low sulfur, low phosphorus, and low moisture. The strength and shatter resistance are relatively poor.

4.Different purposes

Generally speaking, coke products are mostly used in metallurgical industries such as blast furnace iron-making and foundry. However, due to relatively poor strength and crush resistance, semi coke cannot be used in blast furnace production. However, in ferroalloy, calcium carbide, fertilizer and other industries, semi coke can completely replace general coke, and its quality is better than many national standards for metallurgical coke, foundry coke and ferroalloy special coke. Therefore, semi coke is improving the quality of downstream products, saving energy, It has higher application value in terms of reducing production costs and increasing output. At the same time, semi coke also has development potential in the fields of blast furnace injection, production of carbonized materials, and activated carbon.

5.Different market prices

Due to differences in raw materials and processes, the market price of semi coke is much lower than that of ordinary coke. There are three kind of price according to the size:0-6mm 700CNY/ton, 6-18mm 730CNY/ton and 20-34mm 750/ton. But the price of ordinary coke up to about thousand per tons.The relatively low market price makes semi coke have higher market competitiveness.