Category

Theme images by Storman. Powered by Blogger.
Best viewed in Google Chrome

Kilns & Furnace related ...

Labels

Labels

Raw Materials related ...

Advertisement

Popular Posts

Services

Featured Posts

Indian Steelmakers urge PM Narendra Modi to ban iron ore export for six months

- No comments

30-Dec-2020

Hot-rolled coil prices have increased by 46 percent to Rs 52,000 per tonne in November as compared to Rs 37,400 per tonne in July this year. Rebar TMT, which is used in the housing and construction sectors, had touched Rs 50,000 a tonne, industry sources said.

https://www.industry.guru - representative image
Indian steelmaker’s body, the Indian Steel Association (ISA) yesterday wrote a letter to Prime Minister Narendra Modi, explaining that the metal price hike was due to surging raw material costs, and also requested him to impose a temporary ban on iron ore export till the supply side stabilises for the key raw material.

Indian Steel Association currently represents almost all the major Public and Private Sector steel producers of India and intends to be focal point for steel industry related deliberations in the country and abroad.

The Indian Steel Association (ISA) approached Prime Minister’s Office after Union Road Transport and Highways Minister Nitin Gadkari wrote a letter to the prime minister on the impact of rising steel prices on infrastructure projects.

"We would like to highlight some of the very serious and compelling reasons which have left the steel industry with no recourse, but to raise prices of steel from time to time," the ISA said in its letter to the PMO.


Hot-rolled coil prices have increased by 46 percent to Rs 52,000 per tonne in November as compared to Rs 37,400 per tonne in July this year. Rebar TMT, which is used in the housing and construction sectors, had touched Rs 50,000 a tonne, industry sources said.

In their letter ISA mentioned about the issues related to iron ore, price rise of raw materials, shortage in global steel supply and lower capacity utilization because of lockdown due to COVID 19.

"Due to a temporary shortage of steel in the wake of the COVID-19 disruptions, the international prices surged to over USD 750 per tonne from the bottom of USD 397 per tonne witnessed this year. As India is an open economy, the steel prices in the country move up with the global prices," ISA secretary general Bhaskar Chatterjee said.

He also mentioned that iron ore price has increased more than double from Rs 1,960 to Rs 4,160 per tonne in the period of June-December 2020.

"With an increase of Rs 1,000 in iron ore prices, the minimum impact is Rs 2,000 per tonne in steelmaking," Chatterjee said.

Iron ore production in the April-October period of 2020 was at 92.08 million tonne, registering sharp degrowth of 30 percent over the same period last year.

On the other hand, iron ore exports had surged by 70.3 percent to 29.2 million tonne in the first half of the current fiscal.

Explaining why the metal price has been raised, the ISA said Indian crude steel production fell by 19 percent in the current financial year.

"Indian steel industry faced severe disruptions in production caused by the unprecedented COVID-19 pandemic. Consequently, many steel companies in India with sub-optimal operating capacity showed substantial cash losses due to non- absorption of huge fixed costs for the quarter ended June 2020," it added.

(Source: Moneycontrol / PTI, edited)

Chinese steelmaker Jiangsu Shagang to invest $2.25 billion for modernising steel mills in Henan province | Steel Industry News

- No comments

13-Dec-2020


Chinese biggest private sector steel producer, Jiangsu Shagang Group disclosed that it will invest 14.8 billion yuan ($2.25 billion) in buying and modernizing steel mills in China’s central Henan province in a project to create a high-end steel manufacturing facility.

Led by Anyang Yongxing Special Steel Co Ltd, a unit of Jiangsu Shagang based in Henan, the project aims iron making capacity at 4.94 MTPA (million tonnes per annum) and steel making capacity at 5.5 MTPA when complete confirmed by a local media report.

In its report Jiangsu Shagang Group neither disclosed any completion date for its project nor potential acquisition targets by name, but said private mills in the Anyang city area would be involved. Anyang Yongxing currently has iron and steel producing capacity around 1.85 MTPA and 2.22 MTPA, respectively. 


Beijing has been promoting consolidation in its more than one-billion-tonne steel sector in an effort to enhance major producers’ competitiveness and knock out outdated production capacity. China’s Baowu Steel Group has completed multiple acquisitions and takeovers across the country during 2019-20.

China’s Jiangsu Shagang Group founded in 1996, manufactures and sells various steel products wide heavy plates, hot rolled strip coils, high speed wire rods, ribbed steel bars, and other products. Jiangsu Shagang Group markets its products throughout the world.

(Source: Reuters)


Advantages of using Gel Bond and Colloidal Silica in Monolithic Refractories

- 2 comments

5-Jan-2009

What is Gel Bond?

The principle behind this bonding is the formation of a ‘gel’ from a ‘sol’ which surrounds the refractory Aggregates through a network skeleton which, with further heating, develops strength & ultimately goes through sintering to form ceramic bonding. Actually the mechanism is thixotropy, which lies in the fact that some substances, when agitated (under mechanical force), pass from the state of a ‘gel’ to that of a colloidal dispersion ‘sol’ and goes back to the state of a ‘gel’ again when the mechanical forces stop. The phenomenon of thixotropy is based on the theory of dispersion & subsequent flocculation of ultrafine powders. Various sols used in the bonding process e.g. Silica, Alumina, Zircon, and Titania. The incorporation of gel bond in place of conventional binders (High Alumina Refractory Cement) has made it possible to improve the high temperature properties of castable refractories considerably mainly because of the absence of low-melting phases (CA, CA2, C12A7, C2AS, C4AF) and impurities.


Advantages of Gel Bond

Several advantages of the gel-bond compositions compared to LCC & ULCC as have been reported are:

  • Less mixing time since gel bond formulations do not require other minor additives or deflocculants like the cement containing castables.
  • Shorter drying time and so reduced drying flaws. This is because water is not added or required for mixing.
  • Better refractoriness because of the absence low melting phases like- anorthite or gehlinite.
  • Colloidal silica being more viscous than the water, help to maintain more separation of refractory particles which, in turn, provide better thermal shock resistance.
  • Better chemical resistance.
  • Because of the various superior properties of gel bond castables / pumpables as described above, they yield longer campaign life, less downtime and so reduce cost of furnace operation.
  • Longer shelf life since there is no hydratable phase as in LCC, ULCC.


Applications of Gel Bond Castables / Pumpables (Gel Bond Monolithic Refractories)


Because of Gel bond Castables / Pumpables (Gel bond monolithic refractories) have been found to give better results in terms of both conveniences of applications as well as properties in almost all type of industries:

  • in cement industries - high temperature rotary kiln burning zone, rotary kiln incinerators lining
  • in glass industries - outside the Glass Melting Tank furnace and sidewalls and roofs
  • in Blast furnace trough - because of the better flowability these can be more conveniently installed by a pump with reduced installation time
  • in Torpedo and other transfer Ladles then Tundish back-up lining, Electric furnace Deltas and Runners
  • in secondary operations like - Reheating furnace hearth, roof. The installation of colloidal silica bonded castables / pumpables has shown significant improvement especially in reheating furnace roof areas, both during installation and drying (which has been found to take about 60% less time than the conventional ramming mixes & plastics)

Colloidal Silica / Silica Sol

Colloidal Silica or Sol or Silica Sol are the different names, consists of a stable dispersion amorphous silica particles. To achieve this, the silica particles must be small enough such that they are largely unaffected by gravity. Therefore, silica particle sizes are usually of the order of less than 100 nanometers. Initially colloidal silica was used in refractories for the purpose of coating in various applications like ingot casting, investment casting etc. It was during late 80’s when for the first time colloidal silica started to be used as bonding agent in monolithic refractories. During late 80’s refractories based on colloidal silica became available in the market in ramming, gunning and castable formulations. The development of gel bond refractories with colloidal silica as the bonding agent has been a major breakthrough in refractory technology. Since the type of colloidal silica used in refractories is available commercially, it became easy for many to take advantage of this technology. In lieu of conventional binders, colloidal silica can be used as bonding agent in all type of monolithic refractories such as castables, ramming and gunning mixes. Its use in castables has given rise to the convenience of refractory applications by pumping, thus providing a considerable advantage over conventional binders. Another big advantage is that unlike calcium aluminate cement bonded refractories; these refractories do not require following specific temperature parameters for drying and hence reduce drying flaws, installation time. Colloidal silica bonded castables / pumpables not only perform better and reduce costs of furnace operation, but also eliminate work place hazards for workers. The nano sized particles of colloidal silica, due to their higher viscosity consistency, maintain uniform inter-particulate distances resulting in increase of the permeability of the mix and hence provide smooth and speedy drying as well as improved reactivity also increasing the castable sinterability, promoting mullite formation. Colloidal silica bonded castables / pumpables can be extensively used in blast furnace cast house refractories (Alumina - Silicon Carbide - Graphite formulations) as well as for all other applications as mentioned above.

Comparative Chart for Standard Sieves used in a Refractory Testing Laboratory

- No comments

16-Feb-2009

There are three - four types of standard sieves any one of which can be followed for refractory testing or for making refractory formulation. Various standards are such as - American (Tyler), British Standard (BS), Indian Standard (IS) etc., a comparative chart is presented in the following table:    

Indian (IS)

American (Tyler)

British (BS)

Mesh

No

Aperture

(mm)

Mesh

No

Aperture

(mm)

Mesh

No

Aperture

(mm)

570

5.5

480

4.8

4

340

3.353

6

3.327

5

3.353

240

2.399

8

2.362

7

2.411

160

1.60

10

1.651

10

1.676

120

1.201

14

1.168

14

1.204

100

1.00

16

0.991

16

1.003

85

0.842

20

0.833

18

0.853

70

0.708

24

0.701

22

0.699

60

0.592

28

0.589

25

0.599

50

0.500

32

0.495

30

0.500

40

0.420

35

0.417

36

0.422

30

0.296

48

0.295

52

0.295

20

0.211

65

0.208

72

0.211

15

0.149

100

0.147

100

0.152

10

0.104

150

0.104

150

0.104

8

0.075

200

0.074

200

0.076

5

0.053

270

0.053

300

0.053

4

0.040

325

0.040