Displaying items by tag: Pozzolana Portland Cement

Spain: Residents of Cartagena, Murcia, have protested Cemex’s plans to begin mining pozzolan at new sites locally. The Murcia Plaza newspaper has reported that the protestors are calling for a mining ban, in line with their interpretation of the area’s Rural Area of Special Environmental and Social Sensitivity designation.

France: Cem'In'Eu has launched FUSIOCIM, a CEM II/C pozzolan cement, that offers a 43% reduction in CO₂ emissions compared with ordinary Portland cement (OPC). FUSIOCIM has specific CO₂ emissions of 506kg/t. It is suitable for various concrete applications and comes in 25kg bags.

Cem’In’Eu general manager Fabien Charbonnel said "We created Cem’In’Eu with the ambition of reducing the carbon footprint of the cement industry. And we are proving it today with a low-carbon offer that easily replaces traditional cements, without any change for construction professionals. We are convinced that this transition can only be done with pragmatism and taking into account the needs of users.”

India: Birla Corporation has started the kiln at its new 3.9Mt/yr Mukutban cement plant at Nagpur in Maharashtra. The project had an investment of around US$370m and the plant will be run by subsidiary RCCPL. Birla Corporation said that the new plant is the group’s fourth integrated plant and the biggest single cement production line in Maharashtra by capacity. It will be powered by two 20MW captive power plants that use air-cooled condenser technology to reduce water consumption by 90%. The plant was partly built using the group’s MP Birla Cement Perfect Plus product, a Portland Pozzolana Cement, composed of 30 - 35% fly ash, itself a by-product of thermal power plants. Use of fly ash and slag will be scaled up at the site as production ramps up.

“It is no mean feat to complete such a large project under such challenging circumstances with major disruptions on account of Covid-19 which led to several logistical challenges, stoppage of work and a flight of labour from the project site on several occasions,” said Harsh V Lodha, the chair of Birla Group. “Moreover, to achieve 10m man hours of construction with zero accidents and completion of the entire project without a single major accident or fatality, I am told, is a unique achievement in the cement industry.”

Charah Solutions has been steadily building up its fly ash distribution business in recent years with an eye on the supplementary cementitious materials (SCM) market. This week it opened the third of its new series of SCM grinding plants, at Oxnard in California, US. The unit sticks out because it is focusing on grinding natural pozzolans. The plant will receive natural pozzolan by truck and rail and then use Charah’s patented grinding technology to produce pozzolan marketed under its MultiPozz brand. The previous plants in this series mentioned natural pozzolans but this is the first to promote it explicitly.

The change is potentially telling because global demand for granulated blast furnace slag (GBFS) outstrips supply. Both performance benefits and environmental regulations are pushing this. It’s a similar situation for fly ash, also driven by trends to close coal-fired power stations in some countries. As Charles Zeynel of SCM trading firm ZAG International explained in the March 2019 issue of Global Cement Magazine, “...volcanic pozzolans are a potential SCM of the future. This is gaining traction, but it’s slow progress at the moment. This will be the answer for some users in some locations.”

The problem though is that natural pozzolans are down the list of preferred SCMs for their chemical properties after silica fume, GBFS and fly ash. The first is expensive but the latter two were traditionally cheap and easy to obtain if a cement or concrete producer had access to a source or a distribution network. Natural pozzolans are very much subject to variations in availability.

It’s no surprise then that Charah is promoting natural pozzolans in a Californian plant given that state’s environmental stance. It’s unclear where Charah is sourcing their pozzolan from but they are not the only company thinking about this in the US. Sunrise Resources, for example, is working on the environmental permits for a natural pozzolan mine near Tonopah in Nevada. As it described in its company presentation, California and Nevada are the most affected states in the fly ash supply crisis because they are, “...at the end of the line when it comes to rail deliveries from power stations in central and eastern USA.” It also estimated that California used 0.9Mt of pozzolan in its cement production of which about 90% is fly ash. The state produced 9.6Mt in 2015. Other companies are also mining and distributing natural pozzolans in the US as the website for the National Pozzolan Association (NPA) lists. Although, if this line-up is comprehensive, then the field is still fairly select. Most of these companies are based in the west of the country.

One last thing to consider is that various groups are tackling a potential future lack of SCMs for the cement industry by making their own pozzolanic materials through the use of calcined clay. These groups include the Swiss-government backed LC3 project and Cementir’s Futurecem products. Using clay should bypass the supply issues with natural pozzolans but the cost of calcining it requires at the very least an investment to get started.

As concrete enthusiasts often point out, a variant of pozzolanic concrete was used by the Romans to build many of their iconic structures, some of which survive to the present day. To give the last word to the NPA, “What is old is new again: natural pozzolan is back!” If environmental trends continue and steel and coal plants continue to be shut then it might just be right.

Nigeria: Ogbonnaya Onu, the Minister of Science and Technology, has inaugurated a pozzolana cement plant at Bokkos in Plateau state. The plant is currently being commissioned, according to the News Agency of Nigeria. The 5000t/yr grinding unit is intended to produce low cost cement. It consists of six sections: materials handling; grinding; nodulisation; calcination; milling; metering; and bagging. The plant is being run in conjunction with the Nigerian Building and Road Research Institute (NBBRI).

Bangladesh: Shah Cement has inaugurated the world’s largest vertical roller mill (VRM), supplied by Denmark’s FLSmidth, at its Muktarpur plant in Munshiganj. The FLSmidth OK 81-6 Mill has an 8.1m grinding table and six grinding rollers powered by two 5.8MW FLSmidth MAAG Max Drive gear systems. FLSmidth says that the mill is the largest VRM ever to be installed in a cement plant in terms of dimension, operating capacity and installed power. It was put in operation in September 2018

“We are proud to have the world’s largest vertical roller mill as part of our operations. We selected the FLSmidth OK 81-6 Mill for its exceptional efficiency and reduced power consumption – and we are expecting it to deliver as promised. As the largest single-unit grinding mill in the industry, we expect it to meet our production requirements for many years,” said Hafiz Sikander, Director of Operations, Cement Division of Shah Cement Industries.

The mill is designed to produce Ordinary Portland Cement (OPC), Pozzolana Portland Cement (PPC), Portland Slag Cement (PSC) and slag cement types. It is producing PPC at a capacity of 500t/hr at 3500 Blaine with 15% slag. In addition to the OK Mill, FLSmidth supplied the process and layout engineering, along with site advisory. The supporting equipment included FLSmidth Pfister weigh feeders, FLSmidth Airtech process bag filters, process fans and auxiliary equipment from raw material hopper discharge to process bag filter discharge.

Shah Cement Industries is the largest cement producing plant in Bangladesh, with a capacity of 8.0Mt/yr. The company is part of the Abul Khair Group, the largest business conglomerate in Bangladesh.

India: A report by the Cement Sustainability Initiative (CSI) shows that the local cement sector is on track to meet its 2030 targets from the low carbon technology roadmap (LCTR). Direct CO₂ emission intensity fell by 5% in 2017 in the Indian cement sector compared to the 2010 baseline. CO₂ emission intensity, including onsite or captive power plant (CPP) power generation, was reduced by 6.8% compared to the 2010 baseline. The alternative fuels thermal substitution rate (TSR) increased by 5 times from 2010 to 2017. The sector consumed more than 1.2Mt of alternative fuels in 2017.

“Sustainability is a journey, not a destination. In our globalised and interconnected world, no one can solve alone the challenges ahead of us and the only opportunity to succeed is through collaborative partnerships, where the common interests of all are considered as more important than the sum of individual interests. This is exactly the spirit that has animated the CSI’s low carbon journey since 1999. This flagship project - with its members - has developed, implemented and shared collective solutions for measuring, reporting and improving its greenhouse gas reduction performance, year after year,” said Philippe Fonta, managing director CSI.

The CSI and the International Energy Agency (IEA) worked with nine local CSI member companies - ACC, Ambuja Cements, CRH, Dalmia Cement (Bharat), HeidelbergCement, Orient Cement, Shree Cement, UltraTech and Votorantim Cimentos - to carry out the status review on the sector’s performance trends, continuous implementation measures and notable achievements based on the milestones set in the 2013 LCTR. The Status Review Report was developed in consultation with Confederation of Indian Industry (CII), with support from International Finance Corporation (IFC) and the Cement Manufacturers Association (CMA).

The findings of the report show that the direct CO₂ emission intensity was reduced by 32kgCO₂/t cement to 588kgCO₂/t cement in 2017 mainly due to an increased use of alternative fuel and blended cement production, coupled with a reduction in clinker replacement factor. However, the study also shows that significant efforts will be needed to meet the 2050 objectives of 40% reduction. The CO₂ emission intensity (including onsite or CPP power generation) has reduced by 49kgCO₂/t cement to 670kgCO₂/t cement in 2017 compared to the baseline year. The report has highlighted the adoption of waste heat recovery (WHR) systems by local cement plants.

The alternative fuels TSR increased to 3% in 2017 from 0.6% in 2010. More than 60 cement plants in India have reported continual usage of alternative fuels, with 24% of the total alternative fuels consumed as biomass. The share of blended cements used in the total quantity of cement manufactured increased to 73% in 2017 from 68% in 2010, largely due to the market’s growing acceptance of blended cement, emerging awareness of sustainability concepts, the availability of fly ash from thermal power plants and the use of advanced technology. The production of Pozzolana Portland Cement grew to 65% in 2017 from 61% in 2010. The share of Portland Slag Cement in cement production remained flat, at less than 10%, over the same period. The clinker factor reduced to 0.71 in 2017 from 0.74 in 2010.

In August 2018 the Global Cement and Concrete Association (GCCA) said it was taking over the work previously done by the CSI from 1 January 2019.

Nepal: Arghakhachi Cement and Jagdamba Cement are planning to build new cement plants. Arghakhachi Cement is spending US$48m on building a new integrated plant, according to the Kathmandu Post newspaper. The new plant will be launched by mid-2018. The company already operates an integrated cement plant at Birpur in Kapilvastu.

Jagdamba Cement is planning to build a 1500t/day cement plant in eastern Bhairahawa. The new unit will create 400 jobs. The cement producer operates two cement-grinding plants at Bhairahawa and Birgunj. The company produces Ordinary Portland Cement, Pozzolana Portland Cement and Pozzolana Slag Cement products.

Nigeria: Danladi Matawal, the Director-General, Nigerian Building and Road Research Institute (NIBRRI) said the institute’s pilot pozzolana cement plant at Ota in Ogun is ready for commercialisation. He has asked cement producers and other stakeholders to invest in the project, according to an interview with the News Agency of Nigeria reported upon by the Nigerian Sun newspaper.

The pilot project has a production capacity of 2t/day and it is ready for testing on an industrial scale. The unit was commissioned in May 2017 by Ogbonnaya Onu, the Minister of Science and Technology. NIBRRI is also planning a volcanic-based Pozzolana pilot plant in Bokos, Plateau that will be commissioned in 2018.

India: The Ministry of Environment, Forest and Climate Change has decided to form a multi-disciplinary committee to examine the possibility of building cement plants near to power plants to use fly ash. The decision was taken at the ministry's Expert Appraisal Committee (EAC) for thermal power projects in mid-February 2017 following a directive by the National Green Tribunal (NGT) in January 2017, according to the Mint newspaper.

"Only 20 - 30% of fly ash is being currently used in making Pozzolana Portland Cement (PPC). Though there are technologies available worldwide for using 80% of fly ash in cement manufacturing, it is not practised in India for various reasons," said an expert committee convened by the ministry.

A sub-committee may be formed with the representative Ministry of Mines, Ministry of Power, CEA (Central Electricity Authority), Department of Industrial Policy and Promotion (DIPP) and Ministry of Coal to examine the issue. In 2015, about 180Mt of fly ash was produced across India and by 2025 it is estimated to reach 300Mt/yr. Unused fly ash is typically dumped into ash ponds.