General manager: Engineering 
Holtec Engineers Private Ltd. 
New Delhi, India

Senior manager: Engineering 
Holtec Engineers Private Ltd. 
New Delhi, India

Jaypee Rewa Cement (JRC), a division of Jaiprakash Industries Limited (JIL), commissioned their first 1 million tpy cement plant at the end of 1986. This was carried out less than 30 months from the date of placement of the order for the main plant and machinery. An article by the author on this plant, was published in World Cement's January/February 1987 issue, entitled 'India adds yet another one million tpy cement plant'. 

Having successfully commissioned the first unit (Unit 1), JIL contemplated the expansion in less than a year. At that point of time the cement industry was at a relatively low ebb and talk of expansion was considered daring. However, the management was confident of the cement industry's future in the growing Indian economy and decided to proceed. The expansion was planned for the same premises, with provision for this expansion being available in the original plant layout. 

The company placed orders for supply of main plant and machinery in April/May, 1989. The clinkerisation unit of the new plant (Unit 2) designated at 1.2 million tpy capacity was commissioned in April 1991 (less than 24 months from the date of order placement). The new cement grinding and packaging facilities are currently being commissioned (completion expected before March 1992). 

The engineering and consulting services for this Rs. 1740 million expansion project were provided jointly by Holtec Engineers Private Ltd., New Delhi, and their associates Holderbank Management & Consulting Limited (HMC), Switzerland. By present day standards this would be one of the most economical and quickly installed projects of such a large capacity in India. 
 

Most of the infrastructure has remained unchanged from that built for Unit 1. However, suitable additions have been provided for the increased requirements in respect of roads, power supply and water. Even today, the plant does not have a railway siding on site. Its own small railway siding is at Satna, about 50 km away. The rail link to the plant is presently under construction and is expected to be commissioned in 1992. The nearest airports are at Khajuraho and Allahabad, about 175 and 135 km from the plant respectively.

JIL possess two limestone deposits at Naubasta which is adjacent to the plant and Bela which is at a distance of 4 km from the plant. 

Holtec carried out a detailed geological investigation of both these limestone deposits utilizing the latest state-of-the-art computer based techniques, i.e. CADE (Computer Aided Deposit Evaluation) in collaboration with HMC. The application of CADE established: 
 

• the existence of sufficient quantity of the required quality limestone in the two deposits, based on analysis of deposit block models constructed through application of geostatics.
• optimized quarry schedules, based on the required raw mix parameters of the cement plant, for ease of mining operation.
• substantial increase in limestone reserve estimates due to optimized exploitation envisioned through CADE.
• the relatively economical cost of homogenized run-of-mine production.

At Naubasta, the blasted limestone is transported by 3.2 m³ hydraulic excavators and 35 t dumpers, to a stationary crusher situated within the plant. 

At Bela, the blasted limestone is fed to the mobile crusher by a similar 3.2 m³ hydraulic excavators and 35 t dumper combination. The crushed limestone is transported to the plant by a bi-cable aerial ropeway. 

The envisaged raw mix consists of 98% run-of-mine limestone and 2% laterite/iron ore. 
 
 

The entire plant design and engineering was carried out with the objective of ensuring trouble free, smooth operation and adequate inter changeability between Units 1 and 2 to achieve sustained high levels of production. Some of the unique methodology and technological aspects adopted are outlined below: 

Methodology: 
 

• The main machinery suppliers were invited by the company to visit their operating plant and assess the various strengths and weaknesses of the existing facilities/systems for themselves. During their visits, the suppliers received operational feedback from plant personnel and management.
• The consultants' specialist team carried out a plant audit of Unit 1 with a view to obtaining first-hand feedback on plant operation and constraints so that this information could be utilized in improving Unit 1 as well as designing Unit 2.
• Basic engineering viz. main machinery tender specifications, plant layout and GA drawings were jointly conceived at HMC headquarters in Switzerland by HMC, Holtec and JRC.
• Main machinery and auxiliary equipment package selection resulted from a series of discussions between the purchaser, the consultants and the suppliers. The selection package devised was such that it enabled the company to purchase equipment best suited to its technical and economic requirements.

• Ease of operation and maintenance.
• Optimizing conveying distances and manpower requirements.
• To keep the investment low, wherever possible, existing systems were upgraded to make them suitable for both Units 1 and 2 requirements e.g.
• Naubasta limestone crusher capacity planned for upgradation.- The capacity of the limestone preblending stockpile stacker unit, upgraded from 700 tph to 1400 tph. 
• Stockpile storage capacity was also increased from 2 x 30 000 t to 4 x 35 000 t by adding a new reclaimer and associated belt conveyors. 
• The existing 2 x 100 tph capacity open circuit cement mills were made closed circuit by incorporating High Efficiency Separators (HES), thereby increasing the system capacity to 2 x 155 tph.
• The existing mechanical rotary packers replaced by more modern electronic versions.

• Inter changeability between Units 1 and 2 has been ensured at all process sections so that the effect of down- time of critical equipment in both the units is minimal for sustained plant output. 
• Raw material hoppers of short duration storage capacity coupled with the mass flow design of hoppers and their extraction systems have been installed to ensure trouble- free operation. 
• The latest state-of-the-art, on-line bulk analyser and sampler system is being installed between the limestone crusher and the preblending stockpile to facilitate the optimizing of mining operations and minimize quality variations for the kiln. 
• Extensive use of the most efficient pollution control equipment in the plant both for production units as well as material handling transfer points, to meet forthcoming stringent pollution control regulations. 
• To overcome the feeding problems of pozzolana in case of grinding of Portland Puzzolana Cement (PPC) with trunnion bearing mills, a slide shoe bearing cement mill has been selected. Central drive in place of conventional twin drive has been selected for energy saving. 
• The use of a fully mechanized bridge type bucket chain stacker reclaimer system using a pit for storage of pozzolana and gypsum. 
• The installation of new additional electronic rotary packers in conjunction with curved belt conveyors and fast loading machines, thereby avoiding any fall of cement bags during transfer from packers to trucks. 
• QA centralized yet distributed, closed loop, computerized process control system. 
• Captive diesel generating sets (3 x 5.8 MW) to be provided to ensure uninterrupted operation of critical equipment in case of power shortages/cuts from the state grid; bringing the total captive power generation capacity for both Units 1 and 2 to over 29 MW. In view of the current deterioration in grid power availability, this was a very prudent managerial decision. 

The broad specifications of major equipment and its respective supplier(s) are tabulated in Table 1 below: 
 

The total connected load of Unit 2 is around 30 MVA and the estimated power demand is 26 MVA. This demand is the same as that for Unit 1, despite the higher plant capacity because many of the existing facilities are common and some are upgraded to meet the expanded requirements. 

The existing 132 kV switchyard has been upgraded to take care of the additional loads of Unit 2. 

Power is distributed within the plant through the following 5 load centres at either 6.6 kV for HT motors or 415 V for LT motors. 
 

• Load Centre 1: At crusher section (existing) 
• Load Centre 2: At raw mill and kiln section 
• Load Centre 3: At cooler and coal mill sections 
• Load Centre 4: At cement mill and packing sections 
• Load Centre 5: At quarry (existing) 

132 kV switchyard expansion, Bharat Bijlee 
6.6 kV motors, BHEL 
6.6 kV switchboards, Asea Brown Boveri 
Distribution transformers, 415 V LT switchboards, Motors control centres, Crompton Greaves 
LT motors, SPRS transformers,DC motors, Kirloskar Electric 
Thyristor converter panels, Larsen & Toubro 
Slip power recovery system, Asea Brown Boveri 
3 x 5.8 MW diesel generating sets Wartsila, Finland 

The complete control and instrumentation packages have been procured from Asea Brown Boveri Ltd., India (a subsidiary of ABB-Sweden) who had supplied a similar package for Unit 1. For efficient operation, the entire plant has been provided with integrated and distributed digital controls for centralised automatic operation from the following four control centres: 
 

• Limestone crushing 
• Clinkerisation from central control room-2 (CCR-2) 
• Cement grinding from central control room-1 (existing CR-1) 
• Packing and despatch 

The entire plant operation for clinkerisation has been divided between two supervisory processors in CCR-2. However, in the event of failure of one processor, plant operation can be carried out from the other without interruption. 

For raw mix control, the existing on-line X-ray spectrometer system along with microprocessor based computer PDP-11123 installed in the main CCR building, will be used for manual correction of the set points of the raw mill weighfeeders. 

The total length of power, control and instrumentation cables is about 400 km. 
 
 

Most of the civil works were carried out by one of the group companies of JIL except for certain slipform works for the blending silo, cement silos and ESP columns for which M/s Bygging India were engaged. The quantities of the civil work involved in the execution of the Unit 2 is outlined below (excluding the housing colony and other amenities where only marginal additions have been done): 
 

• Excavation: 95.000 m³ 
• Plain concrete: 12.000 m³ 
• Reinforced concrete: 50.000 m³
• Formwork: 130.000 m² 
• Reinforcement steel: 7.500 t 
• Structural steel: 6.000 t 
• Cement:  22.000 t 

• Due to the rocky sub-soil strata, special techniques and efforts were deployed for blasting (muffled blasting) so that the adjoining existing plant structure foundations (of Unit 1) were not affected. 
• Highly mechanised civil construction was adopted involving use of earth moving machinery for excavation, batching plant for concrete making, transit mixers, concrete pumps, tower crane (700 m height) etc. Extensive use was made of heavy duty mechanised material handling equipment.
• Special effort was made by the consultants for the designing and providing of fabrication details and intensive technical supervision of the execution of the following: 
• slip-form work for 6 columns, supporting the bottom slab of the 22.4 m dia. blending silo, simultaneously, along with the outer silo shell up to + 23.5 m level and thereafter the lifting of heavy roof girders along with the slip-form assembly from 23.5 m to 80 m level for their faster erection. By this technique around 41/2 months construction time was saved. 
• slip-form for complete structure involving column and beam elements for supporting the kiln/raw mill ESP up to a height of 34 m. The slip-form assembly was specifically designed to suit the requirements of completing this structure in a short time so that the erection and commissioning of the ESP can match the commissioning schedule of the plant. With this new technique, the slip-form work was completed within 43 days. It would have taken around 140 days with conventional methods, thus saving over 3 months.

The fabrication and machinery erection quantities involved in the execution of Unit 2 are of the following order: 
 

• Steel fabrication: 5000 t 
• Machinery fabrication: 1000 t 
• Machinery erection: 8000 t 
• Insulation work: 14 000 m² 
• Refractory: 3000 t 

• About 15 contractors were employed for fabrication/ erection work supported by JIL's own staff and machinery. 
• A fabrication workshop was developed on site with adequate machinery (including around 150 welding machines) and handling facilities. To save time of transport, the following equipment/components were taken on subcontract by JRC from the main supplier to be fabricated on site (besides the ducts/chutes and normal fabrication): 

• Tertiary air duct 
• Preheater cyclones 
• Gas conditioning towers 
• Fine coal bins 
• Feed bin (cement) for packer

•  Maintenance cranes were procured and installed in their respective buildings, which facilitated smooth and faster erection especially in the raw and coal mills. 
• For the first time, on JIL's request, the consultants designed a tailormade crane for lifting and erecting the grinding table of the Loesche raw mill, with a lifting capacity of 130 t. Use of available built-up girders and sections was made to reduce fabrication time of the crane on site. With the help of this crane the grinding table (5 m dia, 130 t weight) was erected in position in less than one day, instead of 8 to 10 weeks as envisaged originally. This has greatly helped in reducing the critical path for timely project completion. 

The original project cost estimate as approved in May, 1988 was Rs.1340 million. It was once again reviewed after most of the orders had been finalised and the project was at an advanced stage, in August 1990. This updated figure totalled Rs.1740 million. Thus, the specific investment per annual tonne of installed cost works out at Rs.1450 which would probably be one of the lowest considering that the specific investment costs of green field projects in India today is in the range of Rs.3000 to 3500 per annual tonne. 

Out of the total project cost, the import content was only of the order of Rs.127 million, in terms of foreign exchange requirements, which amounts to only about 7.3% of the total project cost. The imports were restricted to the following items of equipment: 
 

• Critical components for blending silo and kiln feed equipment, clinkerisation unit and ESP's from F.L. Smidth, Denmark. 
• Critical components for vertical roller mills from 
• Loesche, Germany. 
• Gearboxes for vertical roller mills and cement mill-3 from Maag, Switzerland. 
• Bulk Material Analyser (PNAA) from Gamma Metrics, USA. 
• Critical components for stacker reclaimers and split sampler from MVT, Germany. 
• Air lift pumps in clinkerisation unit from Claudius Peters, Germany (through F.L.Smidth). 
• Clinker conveyor (pan type) from Aumund, Germany (through F.L.Smidth). 
• Critical parts of Cement Mill-3 from Fuller, USA. 
• Torsion shafts for Cement Mills 1 & 2 modifications from A.Friedr Flender AG, Germany. 
• Rotor assembly for raw mill ESP fan from TLT, Germany (through Loesche). 

The overall responsibility for project management was with the owner. However, a predominent role was played by the Consultants (Holtec and HMC) with regard to coordination, supervision and advice to the owner in respect of multifaceted contracts and technical decisions involving numerous suppliers and contractors. 

Important stages concerning the implementation of this project are enumerated below: 
 

• Appointment of consultants  July, 1988 (Holtec & HMC) 
• Issue of main machinery tenders  October, 1988 
• Order placement for main machinery April/May, 1989 
• Start of civil construction  July, 1989 
• Start of mechanical erection  March, 1990 
• Start of trial runs  February, 1991 
• Commissioning of clinkerisation and cement mill modification  April, 1991 

A constructive and co-operative working environment was established between the owner, its consultants, suppliers and contractors. A flexible attitude from all concerned, coupled with sensible management policy contributed toward the swift progress of the project. This was achieved despite unforeseen difficulties and constraints, in particular the Gulf War! 
 

Just after 1986, when JIL had commissioned their first million tonne cement plant, the cement industry in India was passing through a period of glut. Most of the cement plants were struggling to keep themselves afloat in the changing environment of the free-market and glut situation. However, in mid-1987, JIL considered doubling their capacity at the same premises. Despite apprehension from various quarters, JIL showed tremendous confidence in the future of India's cement industry. 

The company's experience, both in the construction and the management of its first project, has proved useful in the speedy commissioning of its 2nd unit. The company is already considering further expansion plans, for which feasibility studies are under way.