crushing of limestone and clay in dg khan cement factory

punjab government approves five cement plants

The Punjab Chief Minister Sardar Usman Buzdar has approved setting up five new cement plants by the private sector in Punjab province, Pakistan, at an estimated investment of PKR150bn-200bn (US$0.935bn-1.246bn). The winners' names are yet to be disclosed officially, but the market believes approval was given to Lucky Cement, DG Khan, PIOC, Kohat Cement and Fauji Cement Ltd.

Earlier, the cement industry in Pakistan expects double-digit growth in demand of 12-14 per cent for the current fiscal year. The industry assumption is based on factors mainly driven by private sector demand propelled by government incentives and low-interest rates as well as CPEC-related and dam construction.

The management of Cherat Cement Co said that the existing players' capacities are so large that the brownfield expansion is unfeasible for several reasons, including marketing strategy and space availability at plant sites. Another point of concern is that the greenfield project requires a time horizon of 4-5 years.

Pioneer Cement Ltd (PIOC)Pioneer Cement is assessing different sites for expansion or a greenfield project having capacity 10,000tpd at PKR35bn. The company's management mentioned that the existing plant's surrounding area is also easy to acquire, but nothing is finalised yet. The 12MW waste heat recovery (WHR) plant has commenced its commercial operations from 20 October at Punjab. Moreover, 12MW of the company's 24MW coal plant has become operational, with the remaining 12MW expected to come online by the end of 2QFY21.

A company official informed CemNetthat for expansion of its project, two public hearings were held last month for grant of approval for large-scale mining of limestone and clay/shale at Zindapir Dera Ghazi Khan andthe installation of cement plant in Punjab. The company assured all stakeholders that it would meet all environmental standards and install the latest equipment to achieve the set standards. The company is currently waiting for further steps from the governments, the official replied.

The DG Khan Cement Co (DGKC)DG Khan Cement is assessing a 3.6Mta greenfield and a 1.2Mta brownfield expansion. DGKC currently has a total capacity of around 7Mta. The company is in the process of installing 10MW WHR, and 30MW coal-based the power plant in the south, which is expected to come online by the end of FY21 and the total cost of the project will be around PKR9bn.

Kohat Cement Co LtdKohat Cement is expanding by carrying out balancing, modernisation and replacement (BMR) on a coal-fired boiler power plant with the net generation of 16.2MW. It is also setting up an additional cement grinding mill of 300tph. These projects will meaningfully reduce variable cost per tonne. In addition, the management stated that it would announce a greenfield capacity expansion of 7500tpd and is in the process of obtaining a No Objection Certificate (NOC) from the government of Punjab. It is also actively searching for a site. The total cost of the project will be around PKR35bn.

Fauji Cement Company (FFC)Fauji Cement Co is planning a greenfield expansion of 6500-7000tpd as there is no space is available on the existing plant site. The company has applied for a DG Khan location where FCCL is top of the list among all applicants and the final NOC is expected in three months.

Cherat Cement Company LtdWork on installing a 13MW solar power project of Cherat Cement Co has been initiated and is expected to come online in 9-12 months time. This PKR4.1bn project is financed by the loans raised from Meehan Bank.

dg khan cement well-positioned

This week, Pakistani cement producer DG Khan Cement launched the largest cement plant in the country as it commissioned its greenfield project at Hub, in Balochistan province, southern Pakistan. The project represents an investment of PKR40bn (US$345.3m).The project's main EPC supplier was FLSmidth, who started work on the project in 2015 through a US$62m equipment supply contract. FLSmidth provided three crushers for raw material handling, which included two TST jaw crushers (TST 1900) and a Raptor XL1100CE cone crusher, plus two EH 150 x 120 crushers for clay and additives.Loesche supplied the vertical roller mill for raw material grinding with a COPE drive for the project. With a capacity of 654tph (4.7Mta), the Hub plant has the worlds largest raw material grinding mill, which began trial operations this week. The line's cement mill, also supplied by the Germany-based grinding specialist, has a capacity of 445tph for OPC production and is again equipped with a COPE drive.The main pyro-processing equipment included a six-stage, two-string preheater, a two-pier kiln and a Cross-bar cooler (18x70m) plus a 5.75x69m kiln. The plant's main storage capacity includes equipment for limestone, clay and coal and a 26,400t CF silo. The expansion at Hub has boosted the capacity of DG Khan by 2.2Mta of clinker and 2.8Mta of cement. The facility will make it easier for DG Khan to export from the nearby port.There are only five cement units currently operating in the deep south provinces of Sindh and Balochistan with a total cement capacity of 8.5Mta, but the expansion of Hub will improve DG Khan's foothold in the south, where Lucky Cement has the largest capacity.At the end of 2017, DG Khan Cement had 4.2Mta of production capacity, which represented nine per cent of the domestic production. The company is now the third-largest cement producer in the country with the second-largest market share. DG Khan hastwo cement plants located at Dera Ghazi Khan and one at Khairpur District, Chakwal.

The cement producer has been working simultaneously on its northern and southern expansions. However, the 2.8Mta northern brownfield project at Dera Ghazi Khan, Punjab, has been delayed and is expected to be commissioned in 2HFY19. This project is estimated to cost US$150m.Capacity additions to continue 2018-21It is a good time to be in the Pakistan cement sector with approximately 26.25Mta of cement capacity coming on-stream between FY18-FY20, which will take the country's total cement capacity up from 46.92Mta to 73.12Mta a growth of 56 per cent, claims Abba Securities. Northern capacity expansions between 2019-21 will add 17.83Mta of cement production to the country.By 2021, when most expansion projects in the south have been completed, DG Khan Cement is forecast have a market share of approximately 16 per cent in the south, making it the fourth-largest producer in the region. This will be behind Attock Cement (18 per cent), Power Cement (20 per cent) and Lucky Cement (30 per cent). Attock Cement is in the process of adding 1.2Mta cement capacity in the south and Lucky Cement will also add a further 1.8Mta cement capacity in the south by mid-2018. Power Cement has also announced plans for a 2.3Mta capacity addition in the south by 2021.The government also granted licences to 14 prospective cement manufacturers in March 2017, while six more licences are in the pipeline. Areas identified by the government to build further cement plants include Dera Ismai Khan, Kohat and Hairpur, which are rich in limestone reserves.

dg khan khairpur: the self-sufficient cement plant

An overview of the plant and of part of the quarry, set in the deeply-incised landscape of the Salt Range.A Caterpillar dump truck being filled with limestone in the plant's quarry, by a Caterpillar tracked back-hoe excavator.The Wasabi Energy/FLSmidth 8.6MW Kalina Cycle waste heat recovery plant at the Khairpur cement plant.The Wartsila 50DF lean-burn dual-fuel engine, installed at Khairpur.The view from the plant's preheater tower at dusk, with the clinker and cement silos on the left, the plant's orchards in the centre, raw meal silo and limestone shed at the right and the hills of the Salt Range in the distance.The plant is compact and still smart despite its high capacity utilisation rate.Position of the Khairpur plant, in relation to the main cities of Pakistan and significant projects in the Chinese-backed Pakistan Economic Corridor.The Vecoplan shredder, fitted with SSAB Hardox wear-resistant steel hoppers to cope with abrasive RDF.The Eldan Recycling pre-chopper/shredder used at Khairpur for processing of RDF.One of the Windmoller & Holscher AM 2185 tuber machines in use at Khairpur.A Brokk 330 remote-controlled demolition robot is used to de-brick the kiln during shutdowns.A pair of PANalytical CubiX Pro XRD and CubiX XRF machines for quality control at Khairpur cement plant.A view into the kiln at Khairpur.Common Myna birds gathering at dusk on the warm preheater tower.FLSmidth DuoFlex burner.Windmoller & Holscher Flexa 820 flexographic end printer.Paul Maschinenfabrik bag flattener.FLSmidth Atox coal mill.DG Khan Khairpur's control room.Windmoller & Holscher Arcomat 2 bag palletising machine.Olives ripening in the plant's olive groves.The goose-neck at the top of the precalciner, with the fields of the local farmers and other local cement plants in the distance.

Global Cement recently visited the Khairpur cement plant of DG Khan Cement Company, situated at Chakwal in a rural area in Punjab State, northern Pakistan, between Lahore and Islamabad. Despite the remote location, the cement plant is a model of modernity, demonstrating admirable self-sufficiency in a number of areas and boasting many impressive features.

The mineral-rich Salt Range is certainly not just composed of salt, although it contains three large and famous salt mines of Khewra, Kalabagh and Warcha. Coal is also found in the Salt Range, but what brings cement producers to the region is its high-quality limestone, as well as its strategic position in the developing north of Pakistan and the fact that it is now well-connected with the world-class M2 motorway, which winds it way up steep inclines into the hills around the famous salt-water lake and nature reserve at Kallar Kahar from the vast plain of the Punjab below. Indeed, so rich are the hills in limestone that the twin cement plants of Bestway Cement, and the Dandot Cement Factory near Tobar, are within a long stones throw of the DG Khan Cement plant at Khairpur. DG Khan Cement Company is a member of the Nishat group of companies, with businesses including cement, textiles and banking. Global Cement recently visited the Khairpur plant site and was kindly hosted by plant manager Col (r) Hashmat Ali Khan and his colleagues.

DG Khan Cements site was established in 2004, and started production in 2007. The plant was officially inaugurated by the then prime minister of Pakistan, Shaukat Aziz. The plant capacity is around 6700t/day of clinker, or 2.21Mt/year, with cement production capacity of 2.43Mt/year.

The plant has its own limestone quarry, with a lease area of 6798 acres, as well as an argillaceous clay quarry on site. The present working area of the quarry is 1.35km2, and total reserves of limestone are around 646Mt.

The limestone crusher at Khairpur has a capacity of 1500t/hr, sending material to a limestone storage shed with total capacity of 90,000t. An FLSmidth 52.5 Atox mill, fitted with an RAR-LVT 52.5 air-separator, is used for grinding raw materials at a rate of 500t/hr. Prior to the pyro-system, materials are stored and homogenised in a CF silo with capacity of 25,500t of raw meal. The plant uses a two-pier Rotax-2 kiln with tertiary air-duct and an FLSmidth SF 4 x 7F Cross Bar cooler for clinker cooling. A Brokk 330 remote-controlled demolition robot is used to de-brick the kiln during shutdowns. Clinker is transported by pan conveyor to the mammoth clinker storage silo, with a capacity of 110,000t of clinker. The two OK 36-4 vertical roller mills used for clinker milling are each rated at 175t/hr. The three cement silos at the site have a storage capacity of 21,000t each.

Cement quality control is facilitated with the use of technology such as PGNAA and X-ray analysers (PANalytical CubiX Pro XRD and CubiX XRF). The packing house can bag cement at 600t/hr, using six Ventomatic rotary packers operating at 12,000 50kg bags per hour, while there are also 12 loading positions for trucks. Three bulk loaders are available for delivery of 600t/hr of bulk cement, in parallel.

The DG Khan Cement plant at Khairpur has a total power requirement of 31MW, which cannot always reliably be supplied by the national grid. In order to give the manufacturing facility an uninterrupted supply of power, DG Khan Cement has installed two captive power plants. Firstly, the plant features a Kalina Cycle-based waste heat recovery plant with power production capacity of 8.6MW, manufactured by FLSmidth of Denmark. Wasabi Energy provided FLSmidth with front-end engineering design (FEED), procurement and commissioning services in relation to the Kalina Cycle technology. The Kalina Cycle1 process uses a binary working fluid of ammonia and water with proprietary and patented processes for varying the ammonia concentration throughout the system and for heat-recuperative stages for increased efficiency. The use of ammonia permits efficient use of waste heat streams allowing boiling to start at lower temperatures. A binary fluid allows the composition of the working fluid to be varied through the use of distillation, providing a richer concentration through the Heat Recovery Vapour Generator (HRVG) and leaner composition in the low-pressure condenser. As the molecular weight of ammonia is close to that of water, a standard back-pressure turbine can be used.

In contrast to the Rankine Cycle, the non-isothermal boiling that results from the use of a binary fluid with variable composition gives a good match with the thermal characteristics of the HRVG so that more of the heat can be extracted from the energy source to enhance the efficiency of the process. Similar considerations apply at the condensing end of the power cycle. By selecting a suitable ratio of the two components that form the working fluid, the boiling point can be adjusted to suit the temperature of the heat source and extract the maximum amount of heat. With this characteristic, of being able to take full advantage of the temperature differential between heat source and heat sink, the process is ideally suited for extraction of useful heat from low-grade sources such as is found at a cement plant. Efficiency improvements of 15-50% are claimed for this type of application.

The waste heat recovery system at Khairpur has a fluid temperature of 340C and recovers waste heat from the preheater and from the clinker cooler using the patented Kalina Cycle KCS1-2A system specially developed for the cement industry.

Secondly, the plants other captive power generation unit was provided by Wrtsil of Finland and consists of two 18-cylinder dual-fuel natural gas and heavy fuel oil Wrtsil 50DF internal combustion engine electrical power generation units, with a combined maximum power output of 33MW. Each Wrtsil unit can produce up to 16.64MWe in continuous base-load operation with a heat rate of 7608kJ/kWh, which is equivalent to an overall thermal efficiency of 47.3% at the busbars. The Wrtsil 50DF lean-burn dual-fuel engine has become popular for power plant installations in a number of countries. It is one of the most powerful gas-burning engines on the market today and has both low emissions and high fuel efficiency which make it a competitive alternative to gas turbines.

According to Wrtsil, Important factors in the choice of engine were the need for a reliable, cost-effective electricity supply to the cement-making process, with flexibility in the choice of fuel. Fuel flexibility is an important factor in Pakistan as the year-round supply of natural gas cannot be guaranteed, particularly during high demand in winter months. Furthermore, operating an independent power plant for a cement works is advantageous when starting the large motors commonly used in cement mills with their sudden high starting currents. These requirements are all ideally met by theWrtsil 50DF.

When running on natural gas, the gas fuel is supplied at a low pressure (less than five bar) and the engine operates on the lean-burn Otto process. Gas is admitted into the air inlet channels of the individual cylinders during the intake stroke to give a lean, premixed air-gas mixture in the engine combustion chambers. Reliable ignition is obtained by injecting a small quantity of diesel oil directly into the combustion chambers as pilot fuel, which ignites by compression ignition as in a conventional diesel engine. This micro-pilot injection uses less than 1% of the fuel energy required as liquid fuel at nominal load. Electronic control closely regulates the micro-pilot injection system and air-gas ratio to keep each cylinder at its correct operating point between the knock and misfiring limits.

In the diesel mode, the engines run on liquid fuel oil such as heavy fuel oil as in a conventional diesel engine. The engines are fully capable of switching over from gas to back-up liquid fuel instantly and automatically should the gas supply be interrupted or in the event of any other alarm, while continuing to deliver full power. When the situation returns to normal it is then possible to switch back to gas mode.

Khairpur is also a leader in Pakistan in the use of alternative fuels for kiln firing, using solid municipal waste and other industrial and agricultural wastes. The plant uses an Eldan Recycling pre-chopper/shredder, screen, wind-sifter and a further Vecoplan shredder, fitted with SSAB Hardox wear-resistant steel hoppers to cope with the abrasive materials being fed into it. The alternative fuels processing facility at the Khairpur plant is large and impressive. The purpose of the project was to replace the use of imported coal with locally-available alternative fuels including agricultural waste such as rice husk, corn cob, wheat straw, bagasse; textile waste; tyre waste; and refuse derived fuel (RDF) from Municipal Solid Waste (MSW). Incoming wastes are stored in separate piles and are first taken to the shredder for size reduction and then transported to the storage bin. The alternative fuels are then extracted using a double screw conveyor and are taken using a Vecobelt pipe conveyor to the calciner floor before being injected into the calciner combustion chamber, controlled through Schenck weigh-feeders.

The plant site also has its own bag manufacturing facility, operated by Nishat Paper Products Company Ltd, running three lines with Windmller & Hlscher equipment, with a production capacity of 800,000 bags/day, for its own use and for the production of bags for other cement producers in the region. The lines are equipped with Flexa 820 flexographic end printers for in-line operation with tubers for multiwall applications, with a print width of up to 157cm. The AM 2185 tuber is used to make three-ply sacks (although up to four plies could be used), while the AD 2390 sack bottomer is also used on the lines. Twin Arcomat 2 robot palletising machines are used to handle the sacks produced. A Paul Maschinenfabrik bag flattening machine is used to pre-condition the bags before use. The plant produces bags not only for DG Khans cement plants in Pakistan, but also for its competitors, including Bestway Cement, Falcon Cement, Dewan Cement Ltd, Lucky Cement, Kohat Cement and Maple Leaf Cement. The three lines have a capacity of 190 million bags each year.

The Khairpur plant produces Ordinary Portland Cement and Sulphate Resistant Cement, which are sold locally as well as being exported. The DG Khan Cement Khairpur facility is ISO certified for Quality Management Systems to ISO 9001:2015 and for Environmental Management Systems to ISO 14001:2015.

A free medical centre has been established for plant employees and for local residents, while a water reservoir on site has provided relief for locals from the droughts which are common in the otherwise lovely area. Regular internships and training programmes are made available for students and locals at the cement plant.

Notably, the plant possesses its own plant nursery, orchards, olive trees and rose gardens, including over 30 varieties of roses. It also has 20 acres of agricultural and fruit fields for growing its own produce, which is used in the plants canteen, as well as a harvest of around 22t of wheat each year. Products are sold to employees at subsidised rates. Common Myna birds, Acridotheres tristis, enjoy nesting around the top of the preheater tower, no doubt attracted by the warmth of the pyroprocess, but perhaps also by the spectacular views of this tidy and self-sufficient cement plant, situated in an idyllic valley in the heights of the spectacular Salt Range in the Punjab.