High-efficiency carbon-reinforcing agent refers to a high-carbon low-sulfur recarburizer, which is actually a graphitic recarburizer of petroleum coke. The recarburizer of petroleum coke is mainly divided into three categories: calcined coke after calcination, and high temperature. Calcined graphitized petroleum coke, the third is semi-graphitized petroleum coke, the degree of calcination is between the two, and the price is also different depending on the degree of calcination.
Foshan Yoshida semi-graphitized petroleum coke recarburizer indicators are as follows:
Moisture (Mad) /% ≤0.5 GB/T211-2007
Ash (A)/% ≤0.8 GB/T212-2008
Volatile matter (V) /% ≤ 0.8 GB/T212-2008
Fixed carbon (FC) /% ≥ 98 indirect carbonization method GB/T212-2008
Nitrogen (N) /% ≤ 0.2 Oxygen and nitrogen analyzer GB/T214-2007
Sulfur (SI) /% ≤0.3 sulfur analyzer GB/T30733-2014
Particle size Remarks: 0-1mm 0-2mm 0-3mm 0.5-2mm 2-8mm 8-30mm (produced according to customer requirements)
Foshan Yoshida Graphitized Petroleum Coke Recarburizer Index is as follows:
Moisture (Mad) /% ≤0.5 GB/T211-2007
Ash (A)/% ≤0.8 GB/T212-2008
Volatile matter (V) /% ≤ 0.8 GB/T212-2008
Fixed carbon (FC) /% ≥98.5 Indirect carbonization method GB/T212-2008
Nitrogen (N) /% ≤0.03 Oxygen and nitrogen analyzer GB/T214-2007
Sulfur (SI) /% ≤0.05 sulfur analyzer GB/T30733-2014
Particle size Remarks: 0-2mm 1-5mm 8-30mm (produced according to customer requirements)
These are indicators and particle sizes for regular production and supply. The price of recarburizers also varies according to the market. Therefore, if you want to know the latest high-efficiency recarburizer prices, please contact us!
Zhaoqing Gaoyao District Hardware Machinery Parts Factory. The factory is located in Zhaoqing City, Gaoyao District, Lingnan City, Lingnan City, more than 20 kilometers away from Zhaoqing City, adjacent to Gaoming District of Foshan City. The transportation is convenient and the geographical position is very superior. We are willing to cooperate with colleagues from all walks of life to seek common development and continue to provide the best products and services for new and old customers. Our main production, processing and sales: pig iron casting HT150-HT350, ductile iron QT500-QT700. The products use clay sand, resin sand, and medium frequency induction furnace furnace casting process. Use pre-furnace carbon-silicon analytical instruments to ensure product quality. With the principle of multi-variety management and the principle of small profits but quick turnover, the company has won the trust of customers. The factory always pursues the enterprise tenet of “Honesty, Truth, Service, and Satisfaction”, and fully follows the needs of customers and continuously carries out product innovation and service improvement.
The Casting Workshop of Guangzhou Diesel Engine Co., Ltd. is the strongest casting production base in South China and has passed ISO certification. Pingyuan County Hengming Automobile Chassis Manufacturing Co., Ltd. is a famous trademark enterprise in Guangdong Province and has passed ISO quality system certification.is the result of a strong alliance. On the basis of the integration of the original technology and management, the company has increased its investment in production equipment. The company's main production equipment: 5 tons, 20 tons of resin sand production line, 1.5 tons, 10 tons of medium frequency melting furnace each 2 Taiwan, 7 tons, 12 tons of each holding furnace, large shot blasting equipment, large annealing, normal furnace. The inspection equipment includes: pre-furnace carbon silicon analyzer, thermometer, electronic scale, sand analysis equipment, physical and chemical analysis equipment, metallography, and spectral analysis. The company mainly produces cast iron parts, including ductile iron, vermicular cast iron, alloy cast iron and ordinary gray cast iron. The industries involved include: large and medium-sized diesel engine castings, engineering machinery, hydraulic machinery, food machinery, machine tools, mold wind castings, etc., can be supplied according to customer requirements, rough and fine casting.
Production and manufacturing of machine tool castings, with advanced technology and experience, has won the trust and support of our customers. I have always used gray iron casting for machine tool castings. Why do I choose this material? What are the advantages?
Machine tool castings using gray iron casting materials:
1. Due to the large size of machine tool castings, the length can reach several meters; the quality can reach more than 10t, and the wall thickness is 15~30mm. The requirements are: good precision stability and shock absorption, high modulus of elasticity, suitable compressive strength, moderate hardness and excellent wear resistance;
2, the process requires good casting performance, has high resistance to deformation, and is easy to cut, and requires lower production costs, such as melting with a cupola, using a smaller amount of alloying elements.
3. China's gray iron casting machine tool castings generally use HT250 and HT300 to inoculate iron castings as materials. In order to improve the service life of the machine tool, various alloy cast irons such as P-Cu-Ti cast iron, Cr-Mo-Cu cast iron and V-Ti cast iron are widely used.
4, gray iron casting machine tool casting process is more durable, casting performance is better, not only practical, the price is relatively more affordable, so our company has continued to use gray iron casting castings.
In addition to machine tool castings, gray cast iron is also commonly used as casting material for various basic platforms. The main products are cast iron platform plate, test platform, iron floor, coordinate measuring platform, T-slot assembly platform, inspection and marking platform, T-slot ground rail. , machine tool castings, etc. These cast iron platform products are widely used in machinery manufacturing, aerospace, automotive manufacturing, high-speed rail, wind power, electric motors, engine manufacturing and so on.
On Thursday (November 15), the petroleum coke market remained stable for a short period of time. The calcined coke recarburizer was still trading, the anode material and the graphitization coke demand were good, and the aluminum calcined coke was unsatisfactory.
The three major groups of petroleum coke market:
In terms of Sinopec, the trading performance of the petroleum coke market was stable today. The downstream aluminum spot price of the Yangtze River was below the fourteenth consecutive month. In the winter, most aluminum companies have higher cost and no profit margin due to the price of electricity. Some aluminum enterprises in Qinghai have begun to cut production. The market for raw petroleum coke and calcined coke is a negative factor. Most of Sinopec's refineries have recently shipped well, and there is no pressure on inventory. In the case of CNPC and CNOOC, the petroleum coke market in the northwest region still has no pressure and good demand. The petroleum coke market in Northeast China has performed steadily. The downstream calcined coke recarburizer is still trading. The demand for anode materials and graphitization coke is good. Short-term coke prices will also be stable.
Refining petroleum coke:
Today, the refinery of petroleum coke shipments is still stable. Petrochemicals are about to start with a set of 1 million tons/year coking. Today, the price of coke is down by 20 yuan/ton. The price of coke in the first two days has risen too fast, and today it has fallen by 100 yuan/ Tons; petrochemical petroleum coke content decreased to less than 1.0%, today's latest offer 2150 yuan / ton; in addition, petrochemical petroleum coke began to take off today, sulfur content of 2.0%, pricing 1,800 yuan / ton. Overall, the refinery of petroleum coke shipments has slowed slightly.
Calcined coke market:
Shandong Industry and Trade recently produced all the raw materials for calcined coke, and the calcined coke content of new materials was reduced to 2.5%. Recently, domestic aluminum calcined coke shipments are still poor.
20181028 This week, China's carbon-reducing agent market was stable, and the low-grade recarburizer market was affected by the weak downstream trend. The price was difficult to break through, and the inventory of individual enterprises was high. The medium and high grade recarburizers were raised by the price of raw petroleum coke. Impact, corporate cost pressures increase, but limited by downstream acceptance, the price increase process is more difficult to promote, some companies raise prices, mainstream prices rose. Near the heating season, local production restrictions policies are clear, Jiangsu, Hebei, Tianjin and other places have been introduced one after another, production enterprises may be limited or not, and downstream operations have been maintained at low levels.
General calcined coal recarburizer:
This week, the mainstream price of China's general calcined recarburizer market is stable, and the market is generally trading. Downstream enterprises are affected by many factors such as environmental protection and market. The general conditions of operation are relatively stable, the demand side is relatively stable, the downstream receiving mentality is weak, the market price is stable, and there is a downward intention. Production: Ningxia area in the main producing area is currently in normal production, enterprises have more inventory, environmental inspection and acceptance work is in progress, subject to environmental protection strict inspection of the heating season, heavy pollution weather control, market start-up may be limited, stimulating prices. The production of enterprises in North China is normal, but the reaction starts low, the market is generally trading, and the enterprises have inventory.
Downstream: Domestic construction steel prices have risen slightly this week. Weekly inventory decreased significantly, and the steel billet pulled up, and the supply and demand pattern still supported the market. It is learned from the market that the market price has basically maintained an upward trend in the first three days of this week. However, as the snails fell, the trading volume began to fall, and the market mentality returned to the sidelines. "Silver 10" has been more than half. So far, the work before the heating season has not yet fully started, and the market is still based on shock operation. Considering comprehensively, it is expected that the short-term building materials market will rise slightly, within the range of 50 yuan.
Calcined coke recarburizer:
This week, the mainstream price of China's calcined coke market is stable, the price of raw materials is rising, and the production cost of enterprises is high. However, in view of the environmental impact of downstream enterprises, the low starting price, the demand for carbon-reducing agents is relatively stable, and the market is generally trading, but it is subject to cost pressure. Driven, individual companies offer up. Medium-high sulfur calcined coke: This week, the market for high-sulfur calcination coke was stable, and the market price of calcined coke in the market with a sulfur content of 1.5% was increased recently. In terms of production, this week's calcined coke enterprises started to fluctuate less, and most of them are under normal production.
Graphitized petroleum coke recarburizer:
This week, the market price of China's graphitized petroleum coke recarburizer increased. Mainly due to the rising price of raw material petroleum coke, the price is high, and the pressure on the production cost of recarburizer is increasing. Among them, the production of individual enterprises in Henan and Xinjiang was suspended due to environmental protection, and the operating rate declined. The enterprises in Jiangsu, Tianjin and Inner Mongolia started to work stably, but the heating season policy was released one after another, and the market heating season may be limited. In addition, the graphitization enterprises of anode materials in the market started to work one after another, and the output was released. Graphitization and recarburizers are highly concentrated in Inner Mongolia. Enterprises in Jiangsu Province have normal production, good shipments and smooth exports.
Forecast: The market for low-grade recarburizers is temporarily stable, and the market needs to consume inventory. Enterprises mainly rely on the implementation of fixed orders. The medium and high grade recarburizer market enterprises may start to work or will be limited. In addition, the raw material prices are high. Even if the downstream acceptance is weak, the cost pressure will push the market price to rise.
Low-sulfur calcined petroleum coke: 20181026 This week, the market price of low-sulfur calcined coke continued to push up. The inventory of various production enterprises was mostly in the middle and low position. Secondly, the operating rate of downstream graphite electrode enterprises increased, and the purchase volume of low-sulfur calcined coke increased slightly.
The low-sulfur calcination of raw materials in Liaoning has improved this week. The inventory of the company has decreased in the early period. The downstream electrode enterprises have started to purchase actively. The market resources of needle-shaped coke have decreased and the price has pushed up and the Fushun calcined coke market has been traded. This week, the market for low-sulphur screening with calcined coke was stable, and the downstream market was on-demand, with less inventory pressure. This week, the operating rate of Huizhou Petrochemical is still not 50%, the inventory is low, and the downstream receiving is positive.
Medium and high sulfur calcined coke: 20181026 This week, the market of high sulfur calcined coke was stable, and the market price of calcined coke in the market with a sulfur content of 1.5% was increased recently. In terms of production, this week's calcined coke enterprises started to fluctuate less, most of them are under normal production. Shandong Rotary Kiln has been ignited on October 22, and it is expected to be produced in early November. 250,000 tons/year of calcination is currently on the desulfurization equipment. It is expected to be ignited during the year; it is expected that the calcined coke will be out of focus in mid-November; the current calcined coke has been produced normally, with a sulfur content of 3.0% and sales within 2.5%.
As of 20181026, the domestic Shandong market sulfur 3.5% trace elements do not require calcination coke mainstream transaction price acceptance ** yuan / ton; sulfur 3.0% trace elements no requirement for calcined coke mainstream acceptance transactions ** yuan / ton; only require vanadium 400, other The micro-unrequired medium sulfur calcined coke factory mainstream transaction acceptance price ** yuan / ton; all trace elements are required within 300, sulfur content within 2.0% of the calcined coke factory price ** yuan / ton. Export high-end (strict elements of trace elements) indicators of calcined coke prices need to negotiate with the company.
The market outlook: medium and high sulfur calcined coke, it is understood that the recent demand for calcined coke is good, the calcined coke within the vanadium 400 due to rising raw material prices, profit margins, but some customers responded to recent shipments in general, so it is predicted that the price of domestic calcined coke will be next week Still based on stability. The market demand for low-sulfur calcined coke is still good. At present, most enterprises maintain low stocks. It is expected that the price of calcined petroleum coke will continue to strengthen in the short term.
20181019 This week, the mainstream price of China's Recarburizer market is stable, the low-grade Recarburizer market is generally trading, the company's inventory is high, and the medium and high Recarburizer market is better. The heating season is just around the corner, the downstream steel mill's production restriction policy is clear, the company's operating rate is low, and the receiving sentiment is relatively dull. The Rebondurizer market price is generally stable and the possibility of deposit and loss is high. The prices of raw materials in the medium and high-grade Recarburizer market were generally raised after the holiday, and the cost pressure of production enterprises increased. However, due to the limited acceptance of the downstream market, the company's quotation has not been raised.
At present, the main materials of Recarburizer are coal and petroleum coke. The petroleum coke is divided into ordinary calcined Recarburizer and graphitized Recarburizer because of the degree of calcination. After years of tempering in the market, the petroleum coke Recarburizer has gradually replaced the market position of coal-based Recarburizer, and the shipment volume is relatively high.
This week, the mainstream price of China's general calcined Recarburizer market remained stable, and the overall market shipments were generally due to the general consumption of downstream steel mills, and the demand was relatively light. Most of the recalcinated Recarburizer manufacturers are electric calcined anthracite enterprises, self-produced screening, and the environmental protection facilities of the local enterprises in the main producing area are undergoing the inspection and acceptance of environmental protection facilities. If the enterprises fail to meet the standards or restrict production, the market starts will be limited. The production of enterprises in North China is normal, but the reaction starts low, the market is generally trading, and the enterprises have inventory.
Downstream: China's construction steel prices are trading strongly this week. Recently, in the environmentally-friendly production and the leading regions, the stock market digested and enlarged, coupled with the decrease in the shipments of the leading steel mills, the stronger willingness to price, and the support of the construction steel market continued to rise. It is understood that the Ministry of Housing and Urban-Rural Development said that all localities should take effective measures to speed up the progress of construction, increase the construction of supporting infrastructure for sheds, and the terminal demand is still acceptable. However, as the price gradually increases, the terminal transaction will gradually decrease, and the market risk preference will be lower. The high price of the willingness to accept is relatively limited, which is not conducive to the sharp rise in prices. Coupled with the recent snail and steel billet red and green intertwined, resulting in a turbulent mentality in the building materials market, traders are cautious, and the atmosphere is strong. Market outlook: It is expected that the short-term building materials market will fluctuate and strengthen, with a range of 50 yuan/ton.
Calcined Petroleum Coke recarburizer:
This week, the price of China's calcined coke Recarburizer is stable, the raw material price is high, and the production cost of the enterprise is high. However, in view of the environmental impact of the downstream enterprises, the low-level operation, the demand for Recarburizer is relatively stable, the market is generally trading, the late heating season is coming, the calcined coke Prices may fluctuate due to limited production, etc., affecting Recarburizer shipments, or will benefit other quality Recarburizer.
Medium and high sulfur calcined coke: This week, the medium and high sulfur calcined coke market was generally trading, the shipment was stable, the market was slightly weak, and the price of the coke was not adjusted. In terms of production, the production load of Zhaoxing carbon is increasing, and individual enterprises in Shandong Guangrao are not expected to reduce production. It is understood that the impact of this winter's limited production policy on calcined coke enterprises will be less than expected. A new carbon-fired enterprise in Shandong is expected to ignite four new calciners at the end of this month, and the monthly output is expected to increase by about 20,000 tons. There is no inventory backlog, and there is no pressure on the trading market of calcined coke. However, at the same time, after the production load of the enterprise is increased, coupled with the recent poor performance of the aluminum market, the price of domestic medium and high sulfur calcined coke at the end of the month is still at a downward risk, and the estimated range is about 50 yuan/ton. .
Graphitized petroleum coke Recarburizer:
This week, the price of China's graphitized petroleum coke Recarburizer is stable. The price of raw material petroleum coke is stable and the price is high. The pressure on the production cost of Recarburizer is increasing. Among them, the production of individual enterprises in Henan and Xinjiang was suspended due to environmental protection, and the operating rate fell. In addition, the graphitization enterprises of anode materials in the market will start construction in the second half of the year, and the output will be released. Enterprises in Jiangsu Province have normal production, good shipments and smooth exports.
Late prediction: The general market for recarburization of Recarburizer is currently trading, and the stock of enterprises is higher, but the price of raw materials for electric calcination may be lower due to limited production, which stimulates the price of Recarburizer; the price of calcined coke and graphitized Recarburizer is driven by cost. The pressure is increasing, and the price push is stronger.
At the hearing on October 9, 2018, the Supreme Court of India decided to liberalize import restrictions on carbon grade petroleum coke and calcined petroleum coke, while setting import quotas for carbon grade petroleum coke and calcined coke.
India's annual import quota is 500,000 tons of calcined coke and 1.4 million tons of carbon grade petroleum coke, but it is not allowed to be used as fuel. Petroleum coke is a sponge-like solid residue produced during the distillation of crude oil. Its calorific value is 1.5 times that of coal. It is usually used as fuel in electric power, glass, cement, and other industries. Because of the high calorific value of petroleum coke and the much cheaper price than coal, coupled with the loopholes in India's environmental protection tax, petroleum coke has become the most attractive raw material for Indian power stations and cement plants.
For India, petroleum coke is indeed cheap and easy to use, but it also costs a lot of use. India’s sulfur dioxide emissions have surpassed China in 2016 to become the world’s number one. At present, about 33 million people live in sulfur dioxide pollution. Area. To this end, the Modi government is determined to ban the use of petroleum coke as a fuel nationwide!
Petroleum coke market: The results of this hearing are also expected by all parties in the market. At present, Indian buyers are already in contact with Chinese petroleum coke and calcined coke suppliers. India’s two-month carbon-grade petroleum coke and calcined coke imports will soon recover.
China's petroleum coke price: For the current Chinese petroleum coke market, the impact is very limited. The export volume of petroleum coke from major manufacturers in the early stage was basically at the port level and did not enter the domestic market. The import restrictions on the release of petroleum coke in India are mainly to continue the previous export plan, which has little impact on the domestic petroleum coke market supply and demand.
Quota setting impact: The output converted to prebaked anodes is 165-1.7 million tons/year from the set limit. Compared with the demand for prebaked anodes in 2017, the demand for 1.7 million tons is basically the same.
For the Indian aluminum carbon market, the quota set this time basically meets the current demand. However, considering that India's electrolytic aluminum production has grown rapidly in recent years, the growth rate is basically 15%-20%, and the future demand is difficult to meet. There may be two situations in the future:
The first is that annual quotas are raised as demand for electrolytic aluminum increases;
The second is to still limit the current quota, or to increase the relative demand, and instead import more pre-baked anode products.
The second article above is relatively more in line with India's national environmental requirements. For the China Petroleum Coke Industry Chain, both of these situations can share the dividends generated by the development of the Indian electrolytic aluminum industry. Relatively speaking, if the second article is established, it will be more favorable to the domestic petroleum coke industry chain, which can boost the export of prebaked anodes, increase the utilization rate of prebaked anode capacity, and drive the demand for petroleum coke and calcined coke. Moreover, the recent domestic environmental protection policy is more rational, and it is also convenient for carbon enterprises to stabilize production.
180925 China's petroleum coke prices are stable and downward, the short-term market petroleum coke prices will continue to be low, and the low-sulfur calcined petroleum coke recarburizer market will slow down this week.
The three major groups of petroleum coke market:
In terms of Sinopec, the price of petroleum coke in its refinery is stable today. Only the prices of petroleum refineries in individual refineries are slightly adjusted. Among them, the price of Huadong Petrochemical is lowered by RMB 20/ton, and the petrochemical of South China is lowered by RMB 50/ton. Stable, the National Day is approaching and near the end of the month, and the recent coking price is still in a downward trend, so Sinopec's refineries are also mainly shipped, the price is stable.
In the case of PetroChina and CNOOC, the price of petroleum coke in the northeast region is stable today. Daqing and Fushun low-sulfur high-quality petroleum coke continue to insured, and prices are expected to fall sharply at the end of the month. The petroleum coke shipments in the northwest region performed well, and the downstream carbon companies received positive products. In the case of CNOOC, Zhoushan Petrochemical Coking Plant started construction today to implement the latest price. Binzhou Zhonghai Bitumen Coking started to be sold tomorrow, and the Shandong Haihua Group coking unit was postponed.
Refining petroleum coke:
Today is the first working day after the Mid-Autumn Festival, and the price of refining petroleum coke is still “falling down”. Today, Rizhao Yanqiao Port petrochemical coking unit has been out of focus, and shipped according to 3#A. The National Day holiday is approaching, the downstream carbon companies are still enthusiasm for receiving goods, and the refinery shipments are eager. Today, the price of sulfur coke continues to decline. It is expected that the short-term price will continue to stabilize.
Calcined coke market:
Today, the market for calcined coke is stable and the price has not been adjusted. The market price of low-sulfur calcined coke is relatively stable. The performance of low-sulfur calcination coke is general. Some enterprises have obvious inventory. The market price of downstream graphite electrode has risen slightly this week, but the raw materials of enterprises are still purchased on demand, and the environmental protection is further Affected the operating rate is limited. Low-sulfur calcination coke recarburizer market coking is slowing down this week. On the one hand, the downstream purchasing enthusiasm has declined after the price rise. On the other hand, this week, the Liaohe Petroleum Exploration Bureau Co., Ltd. Petrochemical Branch has started a rotary kiln this week. The market share has shifted.
What is carbon additive? Carbon additive is a carbon or petroleum coke follow-up product of black or gray particles (or blocks) with high carbon content. The material is mainly coal and petroleum coke. The petroleum coke is divided into general calcined petroleum coke. (calcined coke or calcined coke) and graphitized petroleum coke. The carbon additive is used to reduce the oxygen content in the molten iron mainly during metal smelting and improve the mechanical properties of the casting. In the new synthetic cast iron smelting process, the amount of scrap steel used is greatly increased. By adding a carbon additive to adjust the carbon content of the molten iron, the production cost is greatly reduced while ensuring the quality of the molten iron.
Types of carbon additive
According to the existence form of carbon atoms, carbon additive can be divided into graphitized carbon additive and non-graphitized carbon additive. Graphitized carbon additive mainly includes graphitized petroleum coke and graphite electrode. Graphitized petroleum coke carbon additive is the most widely used in the foundry industry. The production process is to convert the raw material petroleum coke in a graphitization furnace through a high temperature of 2200-2600 °C, so that the carbon crystallization of the petroleum coke amorphous layer structure is transformed into The high-temperature heat treatment process of the three-dimensional ordered graphite crystal, that is, through the graphitization process, reaches the graphitization state. The non-graphitized carbon additive mainly includes: calcined petroleum coke, coal carbon additive, etc., calcined petroleum coke refers to petroleum coke heated at 1200-1500 ° C high temperature, the treatment temperature is low, and the crystal structure has not changed. Due to the high ash content and volatile matter, coal-based carbon additive is rarely used in electric arc furnace smelting. The indicators for measuring the quality of carbon additives are fixed carbon content, sulfur, volatile matter, ash, nitrogen content and water. After high temperature graphitization, the graphitized carbon additive has a much lower sulfur and nitrogen content than the non-graphitized carbon additive.
Carbon additive index: fixed carbon, ash, volatile matter
The fixed carbon of carbon additive is different from the carbon content. The fixed carbon value is calculated based on the moisture, volatile matter, ash and sulfur content of the sample, and the carbon content can be directly detected by the instrument. The fixed carbon content is high and the ash content is low, so the carbonization effect is better. The high ash content in the carbon additive generates a large amount of soot and slag during the smelting process, increases energy consumption, and increases the labor intensity of the slag.
Carbon additive index: sulfur
The sulfur content of ordinary calcined coke has a relatively high grade, generally less than 3% of sulfur to 0.1%, and the sulfur content of graphitized carbon additive is generally less than 0.05%. In ordinary cast iron, sulfur element has stable cementite and prevents the expansion of graphitization. In the production of ductile iron and vermicular graphite iron, a graphitized carbon additive with low sulfur content should be used. If the sulfur content is too high, the ball will be affected. The effect is to consume more spheroidizing agent and increase the production cost; the calcined petroleum coke carbon additive is used in the production of some gray iron castings because of the lower calcination temperature and higher sulfur content, generally less than 1%.
Carbon additive index: nitrogen content
Nitrogen content is an important indicator of the quality of carbon additive. In general, when the foundry purchases the carbon additive, the first is to pay attention to the price of the carbon additive; the second is the fixed carbon, sulfur, ash, volatile matter, and moisture content in the carbon additive, and less attention is paid to the nitrogen content. Ordinary calcined petroleum coke carbon additive, the calcination temperature is low, and the nitrogen and sulfur contents are high. When producing gray iron castings, the scrap steel itself will bring in a part of nitrogen. If the scrap is added in a large proportion, the amount of carbon additive will increase accordingly. If ordinary carbon calcined carbon additive with high nitrogen content is used, the molten iron is used in molten iron. The nitrogen content will increase significantly. Excessive dissolved nitrogen in the molten iron hinders graphitization, increases the stability of the carbide, promotes the formation of D-type graphite, improves the hardness, and deteriorates the processing properties of the casting.
For gray cast iron, the proper amount of nitrogen can shorten the length of the graphite sheet, increase the degree of bending, passivate the end, reduce the aspect ratio, stabilize the pearlite of the matrix, refine the grain structure and improve the tensile strength of the casting. And the role of hardness. According to the data, when the iron is N>0.012%, there is a possibility of nitrogen hole defects in the casting. Nitrogen pores are commonly found in the interior, surface or near surface of castings. They are round, rectangular and irregular in shape and are one of the common defects in casting production. The graphitized carbon additive is subjected to high-temperature desulfurization and denitrification treatment, and the content of nitrogen and sulfur is very low. The content of molten iron in the molten iron using graphitized carbon additive is generally low.
Factors affecting the absorption rate of carbon additive: The factors affecting the absorption rate of carbon additive are mainly the way of adding carbon additive, the chemical composition of molten iron, the temperature of molten iron, and the particle size of carbon additive.
The recarburizer is mainly a calcined coal recarburizer, a calcined coke recarburizer and a graphitized petroleum coke recarburizer.
(2018.09.21) This week, the domestic carbon refining agent market started to be stable, with good trading, and the prices of all grades were stable. Due to the influence of many factors such as environmental protection and trade wars, the downstream steel mills are affected by many factors such as environmental protection and trade warfare. In general, the shipment of recarburizers is limited. In addition, while the enterprises are in environmental protection, the production is basically stable and there are some stocks. The price factor is small. The overall performance of the post-calcined coke recarburizer market was stable. The company said that although the price is high, the supply and demand side is relatively balanced, and the company is steadily moving forward; the graphitization and recarburizer market has raised the price of individual enterprises, the market is well shipped, and the production situation of the enterprise is relatively high. stable.
General calcined coal recarburizer
This week, the mainstream price of China's general calcined recarburizer market remained stable. The enterprises in Ningxia, the main producing area, started low, and the market supply was relatively stable. The 60th anniversary of the establishment of the autonomous region was a celebration of local transportation. The production in the North China market is stable and the environmental protection pressure is still relatively large. Downstream steel mills are affected by environmental protection, limited start-ups, relatively stable demand, and bearish prices for recarburizers.
The calcined coal recarburizer has a close relationship with the steel market. This week, domestic steel prices have been adjusted and operated steadily. The misunderstanding of the environmental protection policy has been revised. The Sino-US trade war has intensified. The NDRC has indicated that it will increase the infrastructure to fill the shortcomings. Zhenzhen expects long-term demand. In the short-term, the downstream demand performance is acceptable, the inventory is low, and the cost end support is strong. It is expected that the short-term domestic steel market will be consolidating.
Calcined coke recarburizer
This week, the mainstream price of China's calcined coke market remained stable, and the company started to recover more than before, mainly supported by the price of raw material petroleum coke, and the cost pressure was reduced. However, in view of the high price in the downstream market, the price intention is weak, the production enterprises are still shipping, and the price of the carbonizer has not yet fully fluctuated. In terms of petroleum coke, the petroleum coke index of Sinopec's refinery is basically stable, the shipment performance is acceptable, and there is no new change in the device dynamics. As the Mid-Autumn Festival and the National Day are approaching, the refinery's willingness to trade will increase, while the downstream enterprises will purchase more on demand. It is expected that the price of petroleum coke will remain stable in the short term. In addition, due to the upcoming winter heating season in Xinjiang, the downstream enterprises will increase their enthusiasm for receiving goods. Therefore, the petroleum coke in the northwest region is relatively better.
Raw materials: medium and high sulfur calcined coke: This week, the domestic medium and high sulfur calcined coke market was stable, and the coke price was unchanged from last week. This week, environmental protection has not affected the production of calcined enterprises in various regions. It is understood that at present, most of the calcined coke production enterprises are mainly engaged in the implementation of pre-contracts. For the time being, most of them have no inventory pressure. Recently, the downstream part of the contract has begun to reduce prices, and the price of petroleum coke still has downside risks.
Graphitized petroleum coke recarburizer
This week, the market price of China's graphitized petroleum coke recarburizer was stable, the price of raw material petroleum coke fell, and the cost pressure slowed down. Among them, the production of individual enterprises in Henan and Xinjiang was suspended due to environmental protection, and the operating rate fell. In addition, the graphitization enterprises of anode materials in the market will start construction in the second half of the year, and the output will be released. Graphitization and recarburizers are highly concentrated in Inner Mongolia. Enterprises in Jiangsu Province have normal production, good shipments and smooth exports.
Forecast of the market outlook: the price of raw material per-calcined coal will rebound in September due to the limited price of environmental protection acceptance enterprises, and the price of general calcined carbonizer will develop in a stable-up mode. Among them, the price of calcined coke and graphitized recarburizer is driven by cost, and the price may rise.
The recarburizer is a material used to increase the carbon content. The main component is carbon. There are many materials that can be used as a recarburizer. Commonly used are coke and anthracite, calcined petroleum coke, graphitized petroleum coke, and graphite (artificial graphite). , natural graphite) and mixtures made from such materials.
1. Coke and anthracite
Coke is a type of solid fuel. It is obtained by dry distillation of coal under high temperature conditions of about 1000 °C. The main component is fixed carbon, followed by ash, and contains less volatile matter and sulfur. Silver-gray, metallic luster. Hard and porous. In addition to a large amount of coke and iron non-ferrous metal smelting (metallurgical coke), coke is also used in foundry, chemical, calcium carbide and ferroalloys, and its quality requirements are different. For example, for casting coke, it is generally required to have large particle size, low porosity, high fixed carbon and low sulfur content; coking for chemical gasification is not strict with strength, but requires good reactivity, high ash melting point, and coke requirement for calcium carbide production. Try to increase the fixed carbon content.
Anthracite is a hard, dense and high-gloss coal mine. The main applications of anthracite lump coal are chemical fertilizer (nitrogen fertilizer, synthetic ammonia), ceramics, manufacturing forging and other industries; anthracite coal is mainly used in the metallurgical industry for blast furnace injection (blast furnace coal mainly includes anthracite, lean coal, lean coal and gas coal) ).
2. Calcined petroleum coke (calcined coke or calcined coke)
Calcined petroleum coke is a widely used recarburizer, which is obtained by calcining petroleum coke. Petroleum coke is a by-product of refined crude oil. Residual oil and petroleum asphalt obtained by vacuum distillation or vacuum distillation can be used as raw materials for petroleum coke, and then coke is obtained to obtain raw petroleum coke. The annual production of American petroleum coke is about 30 million T. The raw petroleum coke has high impurity content and cannot be directly used as a recarburizer. It must be calcined first.
Raw petroleum coke has spongy, needle-like, granular and fluid states.
Sponge petroleum coke is produced by delayed coking. Because of its high sulfur and metal content, it is usually used as a fuel for calcination and as a raw material for calcined petroleum coke. The calcined plum cotton coke is mainly used in the aluminum industry and as a recarburizer.
The acicular petroleum coke is obtained by a delayed coking process using a raw material having a high content of aromatic hydrocarbons and a low impurity content. This coke has a needle-like structure that is easily broken, sometimes referred to as graphite coke, and is mainly used for the manufacture of graphite electrodes after calcination.
Granular petroleum coke is a hard granule. It is a raw material with a high content of sulfur and bitumen. It is produced by delayed coking and is mainly used as a fuel.
The fluid petroleum coke is obtained by continuous coking in a fluidized bed. It is in the form of fine particles, has no directional structure, high sulfur content and low volatile content.
The burning of petroleum coke is to remove sulfur, moisture, and volatiles. The raw petroleum coke is burned at 1200 ° C - 1350 t ° C to make it substantially pure carbon.
The largest user of smoked petroleum coke is the aluminum industry, 7 which is used to make anodes for the reduction of bauxite. The United States produces smoked petroleum coke, which accounts for about 6% of cast iron enhancers.
3. Graphitized petroleum coke
Graphitized petroleum coke refers to the high-temperature graphitization of petroleum coke. Under the high temperature of 3000 °C, the carbon molecular form in the petroleum coke is changed from an irregular arrangement to a hexagonal uniform arrangement. The agent is most easily decomposed in molten iron.
Characteristics of graphitized recarburizer
1) The low-sulfur graphitization recarburizer has a high decomposition rate and a high absorption rate, and can reach more than 90%.
2) High carbon, low sulfur, low nitrogen, and extremely harmful components.
3) Adding graphite nucleus to molten steel and molten iron, more uniform and finer distribution in molten steel and molten iron, so that the performance is more excellent and stable.
4. Graphite is an allotrope of elemental carbon. Each carbon atom is connected with three other carbon atoms (multiple hexagons arranged in a honeycomb shape) to form a covalent molecule by covalent bonding. . Graphite and carbon products have excellent performance, are increasingly used, and the production capacity and benefits are growing rapidly. There are more enterprises of graphite and carbon products above the scale of China, and the concentration is low. With the rapid development of China's metallurgy, chemical, machinery, medical equipment, nuclear power, automotive, aerospace and other industries, the demand for graphite and carbon products will continue to grow in these industries, and China's graphite and carbon products industry will maintain rapid growth. . Graphite is mainly divided into natural graphite and artificial graphite.
4.1. Natural graphite
Natural graphite can be divided into two types: flake graphite and microcrystalline graphite. Microcrystalline graphite has a high ash content and is generally not used as a carbon reinforcer for cast iron. There are many varieties of flake graphite. High-carbon flake graphite needs to be extracted by chemical methods, or heated to high temperature to decompose and volatilize the oxides. This flake graphite has low yield and high price, and generally does not act as a recarburizer; low carbon scales Graphite has a high ash content and should not be used as a recarburizer; it is mainly used as a carbon reinforcer for medium carbon graphite, but it is not used in large amounts.
4.2. Artificial graphite
Among the above various recarburizing agents, the best quality is artificial graphite. The main raw material for the manufacture of artificial graphite is powdered high-quality simmered petroleum coke, in which asphalt is added as a binder, and a small amount of other auxiliary materials are added. After the various raw materials are combined, they are press-formed and then treated in a non-oxidizing atmosphere at 2500 to 3000 ° C to be graphitized. After high temperature treatment, the ash, sulfur and gas contents are greatly reduced. Due to the high price of artificial graphite products, the artificial graphite breakers commonly used in foundries are mostly cut when manufacturing graphite electrodes.
Recycled materials such as chips, used electrodes and graphite blocks to reduce production costs. In the smelting of ductile iron, in order to make the metallurgical quality of cast iron superior, the carbon-reducing agent should be the first choice of artificial graphite. For this reason, it is better to purchase scrap electrodes from nearby companies that use electric arc furnace steelmaking or electrolytic aluminum production enterprises, and crush them to the required particle size. .