Sintering Project

Customer：CangzhouZongheng Industries Limited

Project duration: 2007-2009

Contract Type: EPC

Contract scope: Design & Engineering, Eqipment manufacture and supply, materials supply, civil work and equipment erection, commissioning of the whole plant

Main technical features：

1) Production capacity is one set of 240 m² sintering machine. The normal utilization factor of sintering machine is 1.20 t/(m².h), the max. value is 1.45 t/(m².h) and the normal annual production of high alkalinity cold sinter is 2.28 million t.

2) Product is screened cold sinter with temperature lower than 120℃. The grain size is 5-150 mm, where the content of those >50 mm is smaller than 10%, and those <5 mm is smaller than 5%. The tumbler strength (±6.3 mm) is ≥75%.

3) Fuel adopts open loop crushing system with pair roller for preliminary crushing and 4 rollers for fine crushing to ensure qualified grain size of finished product. Totally there are 2 series so as to ensure availability.

4) Automatic weight proportioning: while adopting automatic weight proportioning, various raw materials form closed loop constant weight regulation, and form automatic weight proportioning system through setting system and logic control system. The features are stable and reliable equipment operation so as to considerably increase qualification rate and first class rate of sinter and meanwhile reduce fuel consumption per t sinter and reduce BF coke ratio.

5) Measures for intensifying sintering such as addition of quick lime in the mix are adopted to ensure stability and high production of sintering process. The quick lime adopts closed tank truck for pneumatic transfer to maximize the improvement of surrounding environment.

6) Sintering with thick material bed Due to improvement of sintering sealing and increase of negative pressure of main exhaust fan, beneficial conditions are created for sintering with thick material bed. The side wall height of pallet is 700 mm, and the thickness of material bed can be over 650 mm. Sintering with thick material bed can reduce fuel consumption and FeO content in sinter.

7) New type practical ignition furnace for sintering is adopted and BFG with low calorific value is used.

8) In order to stabilize sintering production and extend life time of pallet, grate layer material system is provided, and grate layer material with qualified grain size is obtained through complete screening system.

9) 2 sets of 3000×9000 straight line vibrating screens are adopted in serial to form screening process. The advantages of such process flow and arrangement are: simple process flow, compact arrangement. All cold sinter screening operation can be completed only in one building, with less land occupation, less investment, less personnel. The transfer times of sinter is less and cold return sinter quantity is reduced with easy maintenance. More important, generally the 5 mm screen deck will not be blocked due to impact of large block of sinter.

10) The charge end of sintering machine adopts high efficiency ESP, with higher dedusting efficiency. The dust content in the waste gas after cleaning is ≤80mg/Nm³

11) Hot sinter vibrating screen is cancelled to improve the environment of discharge end, reduce level of platform of main building and save investment. The sinter will be cooled by forced air rotary cooler, featuring simple structure, operation and maintenance.

12) Electrical, instrument and control system

Proportioning equipment, round roller feeder, sintering machine and cooler adopt VVVF mode.

Computer control system is adopted for monitoring and management of the whole plant, and PLC control system is selected.

Instrument with reliable quality and advanced performance is adopted for indication, recording, control and automatic regulation of production process parameters.

Administration telephone, production dispatching telephone, command intercom and industrial TV facilities are equipped. Dust produced during sintering process will be recovered and recycled in the plant, and dust humidifying process is adopted to reduce production of secondary dust.

13) Environmental protection, safety, health and fire fighting

In order to reduce waste water volume in sintering production, the production shop will adopt water spray for cleaning, and cooling water for equipment will be circulated and the circulating rate is over 96%.

In the design, safety and health are completely considered, and lightning protection and fire protection facilities are provided for building. Protection guards are provided for drive part of equipment and handrail and cover plate are provided for all holes, openings in shop to ensure personal safety and physical and mental health of worker during production.

In accordance with design standards, fire hydrant and area fire fighting alarming system are provided in the design. The road in the plant is smooth and complete, and the distance between buildings meets requirement of fire fighting standard, and the building meets requirement of fire resistance class.

240㎡ Sintering Plant of Phase Ⅰfor Cangzhou Zongheng