Commissioning amid a revolution: part two

Firing up

BMIC fired up its kiln by the end of 2012 and experienced a very smooth start-up, suffering from no vibrations, overheating, alignment or any other hindering issues – a further success. Maximum capacity was reached at first start-up and saved the typical six months required to gradually ramp-up capacity.

However, two major issues were faced related to the Gebr. Pfeiffer raw mill and KHD’s pyrofloor cooler. The former was less of a manufacturing or installation problem and more due to unfortunate events that led to a three t roller being manufactured using material that was incompatible with BMIC’s quarry. Originally located near Assiut’s airport, the quarry had to be relocated 6 km further away for security reasons. Despite only being a short distance away, the geological composition of the mine was completely different. The roller corroded after a couple of days’ use and had to be re-welded, during which time the kiln had to be shut down as well. The manufacturer informed us that delivery of the new mill would take around six months and so, again, BMIC had to devise a solution to continue operations and minimise stoppage.

BMIC asked Gebr. Pfeiffer to provide a list of the material used in the mill’s manufacture – a mixture of zircon, nickel, silver and platinum, amongst other materials. The company then contacted a Greek electrode manufacturer and ordered a wire – using these same materials – that was delivered within three weeks. Build-up was applied together with 35 mm hardfacing for segments of the grinding rollers and 25 mm hardfacing for the grinding table, as well as the clamp bows and retainers. This method allowed the mill to operate for a month without stoppage before a re-weld was needed. The plant continued accordingly for six months, after which the new mill arrived.

The second major issue was that the clinker was being produced at a higher than optimal temperature. BMIC had originally installed a second edition pyro-floor cooler PFC650 manufactured by KHD. However, by the time construction was complete, KHD had released the third edition of this cooler. BMIC engineers asked that the cooler be upgraded, a request originally deemed too complicated, as the civil engineering works were only compatible with the second edition. BMIC’s in-house engineer and Plant Manager, Ahmed Mahmoud, came up with design modifications for the structure to convince everyone that it was achievable. The German manufacturer sent a technical team to implement BMIC’s redesign, a cost-effective method of upgrading the second edition to the third edition pyro-floor cooler that is now being adopted globally.

Despite the cooler’s upgrade, clinker temperatures remained higher than desired. BMIC and KHD therefore had to devise a set of upgrades and modifications to address the problem. These included welding two blind plates to the cooler’s static gates, fitting air nozzles and performing anchor and castable works to fit a 12 nozzle horseshoe. Other works included replacing the seal cords for 180 m of the cooler’s lanes, replacing damaged liners separating the movable and static modules, and a complete revamp of the baghouse fan’s impeller. BMIC managed to implement these works in a total of 10 stoppage days, instead of the scheduled one month, by working in 24-hour, around-the-clock shifts, each being supervised by three KHD engineers.

All these issues were faced and addressed during the course of 2013. By 2014, and after having reached production stability, the focus shifted to maximising production capacity. While the design capacity of the kiln is 5000 tpd, BMIC managed to surpass this and was producing c.10% more – a feat that was achieved by altering the burn ratio between the preheater and kiln, as well as the addition of the magnesium-based catalyst serpentinite.

Fuel finding

Perhaps one of the underlying characteristics of Egypt’s post-revolution economy is the chronic fuel and power shortages that have swept both households and industry. Egypt’s power sector has still not made a complete recovery, and although the current government has made some headway in supplying energy to residential consumers, industry is still facing shortages.

After commissioning in 2013 and working on maximising production, BMIC had to secure electricity and fuel. The kiln is designed for heavy-fuel oil, and despite the presence of an oil refinery in the governorate of Assiut, lax road security meant that truckers were refusing to drive at night and would only venture out of the refinery in the early hours of the morning. Fortunately, BMIC was in close proximity to the refinery and, with direct access to the main road, the plant was typically the first stop on the truckers’ route.

In 2011, BMIC was considering investing in a natural gas pipeline to connect its facility to the grid. However, management recognised the natural gas shortage early and ultimately decided against the investment. BMIC was among the first cement companies to propose the use of coal in Egypt, a suggestion that has caught on with several manufacturers that have since modified their kilns for coal and petcoke. BMIC is currently in the final stages of contracting for a coal mill that will make the company fully independent of the state’s fuel supply.

In terms of electricity generation, of key significance is that BMIC is the only plant to feature an independent power generation house, with most other cement manufacturers depending entirely on the state’s electricity grid. BMIC boasts two 25 MW electric generators manufactured by Cummins that it acquired for EGP120 million. The company was, however, set back by the severe diesel shortage that gripped the country after the 2011 revolution. The generators burn some 160 000 litres per day and ensuring a stable supply proved increasingly difficult. In October 2014, the company decided to extend power cables to a distance of 12 km, connecting it to the grid with the generators acting as backup. The Cummins investment was by no means without return, as it allowed the plant to operate at c.92% capacity utilisation during 2013 and 2014 when the industry average stood at 40 – 50%.

This is part two of a three-part article written by Samir Sabry for World Cement’s November issue and abridged for the website. Subscribers can read the full issue by signing in, and can also catch up on-the-go via our new app for Apple and Android. Non-subscribers can access a preview of the November 2015 issue here.

Read the article online at: https://www.worldcement.com/special-reports/28102015/sabry-bmic-cement-difficulties-cement-plant-850/