Product development
Building Durable Structures
Published
8 years agoon
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adminThe National Council for Cement and Building Materials organised a Seminar on ‘Durability and Service Life Design of Concrete Structures’ at its Ballabgarh (Haryana) premises on 7th April, 2017.
Durability of concrete structures is the prime issue of concern for builders and consumers all over the world. Sustainable construction and sustainable development are the goals which the civil engineering fraternity is aiming at today. The time has come to design and construct structures, targeting a specified service life.
This would not only save precious raw material resources and cut down on wasteful activities, but also help reduce the carbon footprint of cement and construction activities, and preserve the environment. To create sensitivity about these issues and bring designers, engineers, builders and consumers – mainly government agencies like PWD, CPWD and development authorities – on the discussion table and exchange ideas and information, the National Council for Cement and Building Materials organised a seminar on ‘Durability and Service Life Design of Concrete Structures’ at its Ballabgarh (Haryana) premises on 7th April, 2017.
The seminar evoked an overwhelming response and attracted participation of about 250 delegates from India and overseas. Technical sessions were organised on (among other topics) ‘Durability and Service Life Design’, and ‘Newer Materials and Sustainability’, with six papers scheduled for presentation in each session. Eminent experts from IITs, government institutions and agencies, along with the cement and construction industry, presented their views through invited lectures, keynote speeches and panel discussions.
Sustainable growth
Welcoming the delegates to the seminar, Ashwani Pahuja, (DG-NCB), said, "For environmentally sustainable economic growth, it is necessary to build concrete structures using sustainable materials and ensure that the built facilities retain their required performance over the long term. Therefore, sustainability, durability and service life design are interrelated and an optimum balance amongst all these three parameters is a must to ensure maximum technological mileage in a given situation." He added that in the absence of proper design of life of concrete structures, the annual expenditure for repair and rehabilitation of these structures would increase.
"Using durable and sustainable materials with maximum service lives would be a fundamental challenge for engineers and scientists. Developing effective and durable concrete and repair materials and prolonging the service life of structures is a challenge for researchers and engineers today," Pahuja noted.
In the first technical session, two keynote speakers, Professor B Bhattacharjee from IIT-Delhi and Professor Manu Santhanam from IIT-Madras presented their views. Professor Bhattacharjee dealt with the issue of ‘Durability and Service Life Design of Concrete Structures in the Indian Context’ and Professor Santhanam spoke about ‘Use of Combined Durability Parameters for Different Exposure Conditions’. The session was chaired by Hasan Abdullah, Director, Ministry of Water Resources, River Development and Ganga Rejuvenation, and co-chaired by Dr Subrato Chowdhury, formerly Chief (R&D), UltraTech Cement Ltd. The session had three presentations from NCB and one from JSW Cement.
Relevant Models
Professor Bhattacharjee presented different zones required for service life prediction of concrete structures in India which presently needs revision in existing standards for plain and reinforced concrete (i.e., IS 456:2000). A few relevant models were discussed and the results were presented by him. A relatively new approach to durability design of concrete was presented. Professor Santhanam presented a fresh way to specify performance parameters for different service environments, by linking the criteria to the prevalent transport mechanisms in that environment.
By using this approach, several concrete mixtures in the study were analysed for their suitability in different service environments – (i) exposed to airborne salt but not in direct contact with seawater (ii) permanently submerged in seawater and (iii) tidal, splash and spray zones. The results presented by him also confirmed the superior performance of concretes with mineral admixtures in chloride-laden environments.
The second technical session had two keynote presentations on service life design and an invited talk. The first keynote speaker, Dr AK Mullick, Former DG-NCB, highlighted important parameters for ‘Prediction of Service Life of Concrete Bridges Designed to New Bridge Code IRC:112’. Thereafter Dr Chowdhury presented his views on ‘Service Life Design and Prediction of Concrete Structures’; the paper was co-authored by Ashok Tiwari. Thereafter, Dr Shashank Bishnoi, Professor, IIT-Delhi, spoke about ‘Modelling of Carbonation in Portland and Blended Cements’.
This session included one presentation each from Ambuja Cement, DCRUST, Murthal, Haryana and NCB. The session was chaired by Professor Bhattacharjee and co-chaired by Sanjay Pant, Head-Civil Engineering, Bureau of Indian Standards, New Delhi.
Dr Mullick presented the new durability provisions introduced in IRC: 112 to guard concrete structures against chloride corrosion and carbonation corrosion. Chances of carbonation front reaching the reinforcement bars under adverse atmospheric conditions (RH between 50 to 70 percent) were minimised by the choice of w/c ratio and cover depth prescribed, provided the concrete is well-compacted and well-cured. The provisions presented by him indicate that additional protection measures may be required, when the concentration of acid-soluble chloride ions on the surface exceeds 1.0 per cent by weight of cement. Dr Chowdhury spoke about the gaps existing in international and national codes and guidelines dealing with service life design of concrete structures.
In his presentation, he laid emphasis on how no approach for service life design of concrete structure adequately incorporates the concrete preparations and executions policy and practice. Dr Bishnoi (Associate Professor, IIT Delhi), Invited Speaker, spoke on the topic of ‘Modelling of Carbonation in Portland and Blended cements’.
The third technical session on ‘Newer Materials and Sustainability’ also included two keynote presentations, one by Professor Radhakrishna G Pillai, IIT Madras, on ‘Effect of Corrosion Inhibiting Admixtures on the Chloride Threshold of Steel and Transport Properties of Cementitious Systems’, co-authored by Anand Godara and Sripriya Rengaraju, and the second by Sanjay Pant on ‘Approach to Sustainability in Construction of Buildings and Built Environment, with Special Reference to Cement and Concrete’.
This session had a presentation by students – one from Shree Cement and one from NCB. The session was chaired by Ramesh Chandra, Special Director General (HQ), CPWD, New Delhi, and co-chaired by Vivek Naik, President Elect-ICI, Apple Chemie India Pvt Ltd.
Professor Pillai dealt with the performance evaluation of different types of corrosion inhibitors. Highlights of the study show that addition of bipolar inhibitors with nitrites could lead to a significant reduction in compressive strength. Nitrites could accelerate the hydration reaction leading to the formation of microstructure with voids, which in turn leads to a lower strength. This should be considered while designing the concrete mix.
Pant spoke about the approach required for sustainability in construction. According to him, building maintenance is a wide subject covering not only maintenance of building services, but also the maintenance of all other aspects, including the structure itself. Effective operations and maintenance is one of the most cost-effective methods for ensuring reliability, safety and efficiency of a building.
Inadequate maintenance of energy-using systems is one of the major causes of energy wastage. Also, inadequate maintenance of systems that consume water, including plumbing and HVAC systems (as applicable), can result in excessive usage of water. Good maintenance practices result in substantial savings in consumption of energy and water, and should be considered as a resource.
The seminar concluded with a panel discussion, featuring experts like Dr AK Mullick, Professor B Bhattacharjee, Sanjay Pant, Ramesh Chandra and Professor Manu Santhanam. The discussion was moderated by VV Arora, Joint Director and Head-Centre for Construction Development and Research, NCB.
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Advertising or branding is never about driving sales. It’s about creating brand awareness and recall. It’s about conveying the core values of your brand to your consumers. In this context, why is branding important for cement companies? As far as the customers are concerned cement is simply cement. It is precisely for this reason that branding, marketing and advertising of cement becomes crucial. Since the customer is unable to differentiate between the shades of grey, the onus of creating this awareness is carried by the brands. That explains the heavy marketing budgets, celebrity-centric commercials, emotion-invoking taglines and campaigns enunciating the many benefits of their offerings.
Marketing strategies of cement companies have undergone gradual transformation owing to the change in consumer behaviour. While TV commercials are high on humour and emotions to establish a fast connect with the customer, social media campaigns are focussed more on capturing the consumer’s attention in an over-crowded virtual world. Branding for cement companies has become a holistic growth strategy with quantifiable results. This has made brands opt for a mix package of traditional and new-age tools, such as social media. However, the hero of every marketing communication is the message, which encapsulates the unique selling points of the product. That after all is crux of the matter here.
While cement companies are effectively using marketing tools to reach out to the consumers, they need to strengthen the four Cs of the branding process – Consumer, Cost, Communication and Convenience. Putting up the right message, at the right time and at the right place for the right kind of customer demographic is of utmost importance in the long run. It is precisely for this reason that regional players are likely to have an upper hand as they rely on local language and cultural references to drive home the point. But modern marketing and branding domain is exponentially growing and it would be an interesting exercise to tabulate and analyse its impact on branding for cement.
Concrete
Indian cement industry is well known for its energy and natural resource efficiency
Published
2 years agoon
November 18, 2022By
adminDr Hitesh Sukhwal, Deputy General Manager – Environment, Udaipur Cement Works Limited (UCWL) takes us through the multifaceted efforts that the company has undertaken to keep emissions in check with the use of alternative sources of energy and carbon capture technology.
Tell us about the policies of your organisation for the betterment of the environment.
Caring for people is one of the core values of our JK Lakshmi Cement Limited. We strongly believe that we all together can make a difference. In all our units, we have taken measures to reduce carbon footprint, emissions and minimise the use of natural resources. Climate change and sustainable development are major global concerns. As a responsible corporate, we are committed with and doing consistent effort small or big to preserve and enrich the environment in and around our area of operations.
As far as environmental policies are concerned, we are committed to comply with all applicable laws, standards and regulations of regulatory bodies pertaining to the environment. We are consistently making efforts to integrate the environmental concerns into the mainstream of the operations. We are giving thrust upon natural resource conservation like limestone, gypsum, water and energy. We are utilising different kinds of alternative fuels and raw materials. Awareness among the employees and local people on environmental concerns is an integral part of our company. We are adopting best environmental practices aligned with sustainable development goals.
Udaipur Cement Works Limited is a subsidiary of the JK Lakshmi Cement Limited. Since its inception, the company is committed towards boosting sustainability through adopting the latest art of technology designs, resource efficient equipment and various in-house innovations. We are giving thrust upon renewable and clean energy sources for our cement manufacturing. Solar Power and Waste Heat Recovery based power are our key ingredients for total power mix.
What impact does cement production have on the environment? Elaborate the major areas affected.
The major environmental concern areas during cement production are air emissions through point and nonpoint sources due to plant operation and emissions from mining operation, from material transport, carbon emissions through process, transit, noise pollution, vibration during mining, natural resource depletion, loss of biodiversity and change in landscape.
India is the second largest cement producer in the world. The Indian cement industry is well known for its energy and natural resource efficiency worldwide. The Indian cement industry is a frontrunner for implementing significant technology measures to ensure a greener future.
The cement industry is an energy intensive and significant contributor to climate change. Cement production contributes greenhouse gases directly and indirectly into the atmosphere through calcination and use of fossil fuels in an energy form. The industry believes in a circular economy by utilising alternative fuels for making cement. Cement companies are focusing on major areas of energy efficiency by adoption of technology measures, clinker substitution by alternative raw material for cement making, alternative fuels and green and clean energy resources. These all efforts are being done towards environment protection and sustainable future.
Nowadays, almost all cement units have a dry manufacturing process for cement production, only a few exceptions where wet manufacturing processes are in operation. In the dry manufacturing process, water is used only for the purpose of machinery cooling, which is recirculated in a closed loop, thus, no polluted water is generated during the dry manufacturing process.
We should also accept the fact that modern life is impossible without cement. However, through state-of-the-art technology and innovations, it is possible to mitigate all kinds of pollution without harm to the environment and human beings.
Tell us about the impact blended cement creates on the environment and emission rate.
Our country started cement production in 1914. However, it was introduced in the year 1904 at a small scale, earlier. Initially, the manufacturing of cement was only for Ordinary Portland Cement (OPC). In the 1980s, the production of blended cement was introduced by replacing fly ash and blast furnace slag. The production of blended cement increased in the growth period and crossed the 50 per cent in the year 2004.
The manufacturing of blended cement results in substantial savings in the thermal and electrical energy consumption as well as saving of natural resources. The overall consumption of raw materials, fossil fuel such as coal, efficient burning and state-of-the-art technology in cement plants have resulted in the gradual reduction of emission of carbon dioxide (CO2). Later, the production of blended cement was increased in manifolds.
If we think about the growth of blended cement in the past few decades, we can understand how much quantity of , (fly ash and slag) consumed and saved natural resources like limestone and fossil fuel, which were anyhow disposed of and harmed the environment. This is the reason it is called green cement. Reduction in the clinker to cement ratio has the second highest emission reduction potential i.e., 37 per cent. The low carbon roadmap for cement industries can be achieved from blended cement. Portland Pozzolana Cement (PPC), Portland Slag Cement (PSC) and Composite Cement are already approved by the National Agency BIS.
As far as kilogram CO2 per ton of cement emission concerns, Portland Slag Cement (PSC) has a larger potential, other than PPC, Composite Cement etc. for carbon emission reduction. BIS approved 60 per cent slag and 35 per cent clinker in composition of PSC. Thus, clinker per centage is quite less in PSC composition compared to other blended cement. The manufacturing of blended cement directly reduces thermal and process emissions, which contribute high in overall emissions from the cement industry, and this cannot be addressed through adoption of energy efficiency measures.
In the coming times, the cement industry must relook for other blended cement options to achieve a low carbon emissions road map. In near future, availability of fly ash and slag in terms of quality and quantity will be reduced due to various government schemes for low carbon initiatives viz. enhance renewable energy sources, waste to energy plants etc.
Further, it is required to increase awareness among consumers, like individual home builders or large infrastructure projects, to adopt greener alternatives viz. PPC and PSC for more sustainable
resource utilisation.
What are the decarbonising efforts taken by your organisation?
India is the world’s second largest cement producer. Rapid growth of big infrastructure, low-cost housing (Pradhan Mantri Awas Yojna), smart cities project and urbanisation will create cement demand in future. Being an energy intensive industry, we are also focusing upon alternative and renewable energy sources for long-term sustainable business growth for cement production.
Presently, our focus is to improve efficiency of zero carbon electricity generation technology such as waste heat recovery power through process optimisation and by adopting technological innovations in WHR power systems. We are also increasing our capacity for WHR based power and solar power in the near future. Right now, we are sourcing about 50 per cent of our power requirement from clean and renewable energy sources i.e., zero carbon electricity generation technology. Usage of alternative fuel during co-processing in the cement manufacturing process is a viable and sustainable option. In our unit, we are utilising alternative raw material and fuel for reducing carbon emissions. We are also looking forward to green logistics for our product transport in nearby areas.
By reducing clinker – cement ratio, increasing production of PPC and PSC cement, utilisation of alternative raw materials like synthetic gypsum/chemical gypsum, Jarosite generated from other process industries, we can reduce carbon emissions from cement manufacturing process. Further, we are looking forward to generating onsite fossil free electricity generation facilities by increasing the capacity of WHR based power and ground mounted solar energy plants.
We can say energy is the prime requirement of the cement industry and renewable energy is one of the major sources, which provides an opportunity to make a clean, safe and infinite source of power which is affordable for the cement industry.
What are the current programmes run by your organisation for re-building the environment and reducing pollution?
We are working in different ways for environmental aspects. As I said, we strongly believe that we all together can make a difference. We focus on every environmental aspect directly / indirectly related to our operation and surroundings.
If we talk about air pollution in operation, every section of the operational unit is well equipped with state-of-the-art technology-based air pollution control equipment (BagHouse and ESP) to mitigate the dust pollution beyond the compliance standard. We use high class standard PTFE glass fibre filter bags in our bag houses. UCWL has installed the DeNOx system (SNCR) for abatement of NOx pollution within norms. The company has installed a 6 MW capacity Waste Heat Recovery based power plant that utilises waste heat of kiln i.e., green and clean energy source. Also, installed a 14.6 MW capacity solar power system in the form of a renewable energy source.
All material transfer points are equipped with a dust extraction system. Material is stored under a covered shed to avoid secondary fugitive dust emission sources. Finished product is stored in silos. Water spraying system are mounted with material handling point. Road vacuum sweeping machine deployed for housekeeping of paved area.
In mining, have deployed wet drill machine for drilling bore holes. Controlled blasting is carried out with optimum charge using Air Decking Technique with wooden spacers and non-electric detonator (NONEL) for control of noise, fly rock, vibration, and dust emission. No secondary blasting is being done. The boulders are broken by hydraulic rock breaker. Moreover, instead of road transport, we installed Overland Belt Conveying system for crushed limestone transport from mine lease area to cement plant. Thus omit an insignificant amount of greenhouse gas emissions due to material transport, which is otherwise emitted from combustion of fossil fuel in the transport system. All point emission sources (stacks) are well equipped with online continuous emission monitoring system (OCEMS) for measuring parameters like PM, SO2 and NOx for 24×7. OCEMS data are interfaced with SPCB and CPCB servers.
The company has done considerable work upon water conservation and certified at 2.76 times water positive. We installed a digital water flow metre for each abstraction point and digital ground water level recorder for measuring ground water level 24×7. All digital metres and level recorders are monitored by an in-house designed IoT based dashboard. Through this live dashboard, we can assess the impact of rainwater harvesting (RWH) and ground water monitoring.
All points of domestic sewage are well connected with Sewage Treatment Plant (STP) and treated water is being utilised in industrial cooling purposes, green belt development and in dust suppression. Effluent Treatment Plant (ETP) installed for mine’s workshop. Treated water is reused in washing activity. The unit maintains Zero Liquid Discharge (ZLD).
Our unit has done extensive plantations of native and pollution tolerant species in industrial premises and mine lease areas. Moreover, we are not confined to our industrial boundary for plantation. We organised seedling distribution camps in our surrounding areas. We involve our stakeholders, too, for our plantation drive. UCWL has also extended its services under Corporate Social Responsibility for betterment of the environment in its surrounding. We conduct awareness programs for employees and stakeholders. We have banned Single Use Plastic (SUP) in our premises. In our industrial township, we have implemented a solid waste management system for our all households, guest house and bachelor hostel. A complete process of segregated waste (dry and wet) door to door collection systems is well established.
Tell us about the efforts taken by your organisation to better the environment in and around the manufacturing unit.
UCWL has invested capital in various environmental management and protection projects like installed DeNOx (SNCR) system, strengthening green belt development in and out of industrial premises, installed high class pollution control equipment, ground-mounted solar power plant etc.
The company has taken up various energy conservation projects like, installed VFD to reduce power consumption, improve efficiency of WHR power generation by installing additional economiser tubes and AI-based process optimisation systems. Further, we are going to increase WHR power generation capacity under our upcoming expansion project. UCWL promotes rainwater harvesting for augmentation of the ground water resource. Various scientifically based WHR structures are installed in plant premises and mine lease areas. About 80 per cent of present water requirement is being fulfilled by harvested rainwater sourced from Mine’s Pit. We are also looking forward towards green transport (CNG/LNG based), which will drastically reduce carbon footprint.
We are proud to say that JK Lakshmi Cement Limited has a strong leadership and vision for developing an eco-conscious and sustainable role model of our cement business. The company was a pioneer among cement industries of India, which had installed the DeNOx (SNCR) system in its cement plant.
Concrete
NTPC selects Carbon Clean and Green Power for carbon capture facility
Published
2 years agoon
October 12, 2022By
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