Analysis of the pros and cons of refractory industry developing in Henan

• resource. Henan abundant natural resources refractory materials, in addition magnesia raw materials, other materials varieties, good quality. Henan bauxite reserves amounted to 280 million t, ranking second in the country. In addition, Henan coal, electricity and other energy sufficient, based on a variety of materials fused, synthesis, sintering, homogenizing and other materials has accounted for a large share of the domestic market and exported to Europe, America and Southeast Asian countries enjoy a high reputation. However, raw material mining method behind wasteful mining, mining the rich abandoning the poor, less than 50% recovery of ore mined, serious waste of resources. In the processing of raw materials, the former state-owned mining enterprises have cut everywhere is a small vertical kiln firing process, shoddy, low value-added products.
• the production capacity. After the reform and opening up, the rapid increase in Henan Province, refractory raw materials companies, state-owned, collective, individual launched. In 1993, according to industry statistics, the production of refractory materials about more than 1,000 enterprises, these enterprises under the 15 cities in the metallurgy, building materials, chemical industry, light industry, township collective and individual enterprise systems, the majority located in Longhai, both sides Jiaozhitielu, Beijing-Guangzhou line west region. In recent years, the production capacity is too large, lack of some companies started in Guantingbingzhuan, partially stopped, the individual state-owned enterprises have declared bankruptcy. According to industry estimates, the existing materials and refractory enterprises in Henan Province more than 600 mines, one on the yield, in terms of capacity, still heavily saturated.
  
  Data show that in 1999, Henan Province, three million tons of refractory materials production, production of 2.797 million tons of refractory products, which firebrick 1,944,000 t, unshaped 625,000 tons, 228,000 tons of other products. Thus, a single from the production perspective, the WTO, refractory materials and products export of Henan has a strong strength.
• enterprise scale.  Luoyang, Puyang, Xinxiang, Kaifeng and other places also has a strong focus on corporate strength. While other enterprises, especially small and medium enterprises, technology is weak. A few years ago, companies in different forms in some universities with a refractory professional commissioned training a lot of students, has now become the technology backbone. In recent years, some of the institutions as well as enterprises in Henan Province has trained a lot of talent, but the technology is still far from meeting the needs. After the accession of scientific and technical personnel knowledge requirements will be more stringent, both have a wealth of expertise, but also has a high level of foreign language and are familiar with WTO rules and international economic law. Obviously, the WTO, whether they have talent for business will be the most serious challenge.
• product structure and quality. Henan ordinary products, less quality products, 60% of ordinary clay and high alumina bricks, products similar serious. This situation, largely reducing the output efficiency of existing assets, weakening competitiveness. In recent years, the province exported product quality and international market requirements compared to some unstable products quality, chemical composition, size and appearance can not meet the accuracy requirements. Product packaging and after-sales service, etc.,
  
  there still exist many problems. Thus, after joining the WTO, the country with the same refractory industry in Henan Province, will face the challenges and opportunities coexist. On the basis of resources, production capacity, production costs, Henan has obvious advantages, but the production equipment, product structure, technology and product quality, except for a few companies have the advantage, most small and medium enterprises are relatively worse.

The refractory of burner secondary

A non-oxidizing furnace air ratio due to the reduction, a reducing atmosphere is formed, so the exhaust gas contains a large amount of carbon black. To remove the carbon, the need for a secondary combustion, but the secondary combustion burner attached to the kiln in the internal lining of refractory material with a special shape, for mixing with the combustion air with high efficiency, using a secondary combustion burner to a stable state However, after the high temperature stability of the region, due to the exhaust gas can be spontaneous, so almost no auxiliary burner.

Further, when the asphalt impregnated refractory firing,

the exhaust gas contains benzo flowers, over 800 ℃ glass printer after the secondary combustion gas exhaust prior to discharge to protect the machine, using the dilution air cooling. With this operation due to large heat loss, so that the future need for cooling in the heat exchanger before dilution to improve combustion efficiency.

Although the total amount of fuel in the kiln is reduced, but because production resulting brick firing tunnel kiln operating rate is reduced, so that fuel consumption may not be reduced. On the other hand, due to the low sulfur fuels, as well as gas treatment, significantly reducing the pollution of the environment. Meanwhile, the operating environment has also been improved, although there is dust in

the work site, but has reached a level not need to wear a dust mask. In the refractory market, large quantities of products will remain subject to lower prices of imported products, the pressure that has further enhanced the trend of small quantities of many varieties.

Mullite basic knowledge

Mullite (or Mok Stone) is composed of a series of aluminum silicate minerals collectively, this type of mineral relatively scarce. Mullite is an aluminum silicate mineral is generated at high temperatures, the formation of the artificial heat aluminosilicate mullite. Natural mullite crystals elongated clusters of needles and showed radiation, MO quarry was used to produce high-temperature refractories.

Feature

• Mullite is a high quality refractory material, it has a uniform expansion, excellent thermal shock resistance, high load softening point, a small high-temperature creep value, hardness, chemical resistance and good features, there are mainly high-purity fused mullite, fused mullite general, all-natural bauxite ore sintering mullite and mullite light burning.
• High temperature mullite insulation bricks are of the introduction of new technology, the newest type of energy-saving refractories, high temperature, high strength, thermal conductivity, energy-saving effect is remarkable characteristics, suitable for medium petroleum cracking furnace, stove metallurgy, ceramics roller kiln, tunnel kiln, kiln porcelain drawer, glass and a variety of electric crucible furnace lining, direct contact with the flame, by the relevant technical supervision departments to detect and use of similar foreign products meet the technical specifications of the product.
  
  Mullite, sintered corundum brick, zircon brick, silicon carbide products, each corundum mullite refractory raw material is a high quality, uniform mullite expansion, excellent thermal shock resistance of mullite, mullite high load softening point, a small high-temperature creep value mullite, mullite, hardness, chemical resistance mullite good.
• Mullite is composed of a series of aluminum silicate minerals collectively, this type of mineral relatively scarce. Mullite is an aluminum silicate mineral is generated at high temperatures, the formation of the artificial heat aluminosilicate mullite. Natural mullite crystals elongated needles and showed radiation clusters. Mo quarry was used to produce high-temperature refractories. Mullite Al2O3-SiO2 is often depressed unique binary stable binary compound of the formula 3Al2O3-2SiO2, Natural mullite is very small, typically by sintering method or synthetic fused. Density: 3.16g/cm3 formula: A1xSi2-xO5.5-0.5x.
• Mohs hardness: 6-7 Refractoriness: 1800 ℃ remains stable when, 1810 ℃ decomposition of corundum and a liquid phase. Mullite is a high quality refractory material,
  
  it has a uniform expansion, excellent thermal shock resistance, high load softening point, a small high-temperature creep value, hardness, chemical resistance and good features, there are mainly high-purity fused mullite, fused mullite general, all-natural bauxite ore sintering mullite and mullite light burning.

Insulating bricks Introduction

Shape with regular insulation products. Are lightweight insulation refractory materials. The common feature of these materials is the volume density, light weight, low thermal conductivity. But lower strength, high-temperature heavy firing shrinkage is large.

Insulating bricks classification.Usually divided into three types: 

• ordinary Insulating bricks, use at temperatures below 1000 ℃, mainly diatomite brick, expansive razor brick, brick, expanded perlite, and more as an insulation layer of thermal equipment. 
• refractory Insulation bricks, using a temperature between 1000-1500 ℃, mainly light clay brick, silica brick lightweight, lightweight aluminum brick and so on. 
• high-temperature Insulating bricks, using a temperature above 1500 ℃, and can be directly used as a high-temperature furnace lining, there are lightweight corundum brick, alumina and zirconia hollow ball products, hollow ball products.
• Ultra-high temperature Insulating bricks, such as by a fibrous silica fibers, alumina fibers, carbon fibers, nitrogen fibers, silicon carbide fibers, at least one heat-resistant inorganic materials such as silica, alumina, lithium oxide, magnesium oxide and clay knot material as raw material, molding and sintering. This brick lightweight, high strength, excellent heat resistance and ultra-high-temperature thermal conductivity, ease of processing, apply to the universe aerospace equipment, industrial kilns and so on.

Four measures to be taken to enhance the refractory industry of the outskirts in 2014

• First, strengthen the management and control of resources. This year, the region will be a total ban on the technology behind the serious pollution, waste of resources ettringite soil shaft kiln firing, and effectively improve resource utilization. Meanwhile, anchored by the letter of the
  
  Central Administration Bureau was established resistant aluminum, relying on large enterprise group integration and restructuring of resources, build regional distribution of refractory materials and products trading center.
• The second is to promote joint upgrade. Support the strength of the refractory business district scale development, guided by the market, the government bypass, actuator and other policies to encourage enterprises to go Waiyinneilian equity transactions, etc., cooperation and win-win road . 
• Third, innovative marketing model, the refractory industry to promote new technology, information technology, network forward.
• Fourth, give full play to the refractory quality inspection center, the role of the Institute of refractories, refractory Association, accelerate the integration of scientific research and technology, enhancing the overall refractory industry product development capability. This year, the district government formulated the "refractory industry to promote the healthy development of opinions", the integration of the various policies of the capital of 10 million yuan, the region refractory enterprise 
  
  upgrading, renewal of equipment, joint restructuring, product development, etc. give strong support.

Using Green Refractories has become inevitable

Currently, Europe, Japan, the United States and other countries and regions due to mandatory government has basically no chromium refractories, using green refractory materials  has become an inevitable trend.

Future expansion of the cement kiln refractories can benefit from a similar promotion of energy saving policies in cement kilns, the Luoyang Yilong and other enterprises developed spinel, magnesium, iron and magnesium spinel hercynite brick in a large the new dry-process cement kilns firing zone and transition back to use, meet or exceed the life of magnesia-chrome brick, magnesite-chrome brick can replace significantly reduces the chromium contamination.

In today's increasingly scarce national resources, new green and energy saving has become refractory development purposes.

China Refractories Association also believes that five-second period, the development of refractories will present new features, which is based on improving product quality and application level, the focus is to increase or enhance new meaning, namely energy saving and low-carbon. The basic orientation of technological development based refractories innovation as the basic starting point, take the design and application of scientific refractories, production, refinement and application of green technology, resource conservation and consumption reduction of the road of integration, to promote research and development re-a new level.

Green Refractories ideas for understanding and behavior should be guided by the concept of systematic, balanced. For refractory industry, should be prepared to produce raw materials, construction, application and after treatment with various aspects of scientific and systematic consideration, avoid thinking and look beyond the surface and one point or the other.

Should think big, start small, face reality, be focused, strongly advocated the user side, the production side, the development side, co-operation and coordinated the design side. As a business, we should strengthen co-operation with research institutions and user units, increase research cooperation efforts in the green refractory technology to achieve new breakthroughs.

The overall level of development of China's refractory industry from advanced green there is a certain distance. Green Refractories and related industries have attracted attention. Relevant government departments and industry associations have also developed a corresponding policies and measures to encourage and promote the refractory green jobs.

Strengthen energy conservation, development of green, low-carbon refractory products, 

is the fundamental requirement of a global green economy strategy for the refractory industry. Refractory industry to further promote technological innovation, product structure adjustment and application of technology to enhance, develop long life energy-saving, environmentally-friendly new green refractory products, refractory industry has become a major trend in the development of the current.

Refractory recycling in iron and steel enterprises

Each of the major units of steel companies have scrap refractories production, mainly refractories are produced in routine repairs ,overhaul repair and removal of industrial furnaces process. Each year, 70% of refractory consumption is used in the steel industry. With the development of the global steel industry, especially in China's steel production with rate of 20% per year rapid growth has also increased the consumption of refractories. Therefore,how to achieve recycling refractories, has become an important aspect of the steel industry to achieve circular economy.
In terms of how effective use of waste refractories, the Japanese steel industry has done a lot of work in recent years, actively promote the study of refractory materials for reuse in various steel plants. For example, a steel company using refractories 4100 tons per month, of which 1,003 tons, representing 24% of refractories will become obsolete, the plant will be one of 750 tons used as paving material, with the rest as a resource recycling.

Their techniques in refractory recycling in terms of: (1) the disintegration of recovery respectively. A refractory used in the furnace due to the kind of the different parts and different. All kinds of used refractory mixed together, make the quality of management of refractory difficult to operate, so before making re-use, recycling must be classified. It Were recycled by the category of magnesia, alumina, and a carbon-based, no-carbon-based and so on. Further, mixing of dissimilar materials or iron, must by magnetic separation methods to separate them. Recycling the used refractory required to be crushed to 200mm ~ 400mm, shock used in the subsequent step of crushing, compression, or shear further crushed into a more manageable size of 20mm or less. For iron sheet scrap refractory, electromagnetic separation, with more than 12,000 Gauss magnetic strength, so that the particle size of the refractory material of the iron content of 5 ~ 10mm is reduced to 2% or less. Powder that crushed and reused after removal of iron as a raw material, the particle size is required to be managed separately. Grading is generally used to make a metal mesh sieve, mesh size according to need, a large mesh size in the above, the following small mesh size, continuous screening. Crushing, grinding and classification process should pay attention not to spread of dust, to seal the devices, recycled in the Dust. The collected dust may be added to the feedstock tile production landscape.(2) an appropriate proportion of the insertion of a new refractory raw materials. Inserted as a raw material, the particle diameter of 5 ~ 20mm, or 1 ~ 5mm, added at a ratio increases, the amount of water added should be increased, so that the porosity increases the durability of the product to be reduced. Given this tendency, the site should be noted that the addition ratio of recycling and use of the material. Wet spray stoppage particle size 1 ~ 5mm, dry spray particle size is less than 1mm stoppage. Material recycling is difficult to completely remove iron and impurities, such as adding more than 20% recycled material, and which due to the harmful effects of impurities contained in leaving less durable. A small amount of scrap refractory SiO2, CaO slag and other ingredients, can reacts with new materials which in Al2O3, MgO, SiC, generate low melting compound. Therefore, we must control the insertion of the amount of recycled material. Cascade scheme can be used, the use of advanced refractory after that, as the first intermediate refractory recycling, re-use as a lower refractory

China's steel enterprises, also re-utilization of the refractory actively explored. They will be more than 80% with the MgO-C as a raw material, with the same quality reproduction of the MgO-C; will use the ladle refractories and related the carbon products, all the re-production of slagging agent metallurgical materials; will use the magnesia-chrome brick reproduct to Gunning mixes.