Packaging, across the value chain of cement operations, is a crucial process. ICR explores the various aspects of cement packaging, and its different types, while assessing the challenges and innovations that are expected in the future.
India is one of the largest producers of cement. With the ongoing infrastructural development in the country, the demand is ever rising for cement. Similarly, India also exports a significant amount of cement. Cement from the manufacturers must travel the lengths of the country to reach the users and cross borders during export. This requires strong packaging to avoid coming in contact with moisture and prevent wastage due to leakage. Once cement comes in contact with moisture it turns into concrete and that makes it of no use.
Packaging of cement plays a crucial rule in the process of taking it from the makers to the consumers. Manufacturer’s source highest grade technology and packaging material to protect their product from damage, wastage and to reach the end user in an unharmed manner. Packaging happens at the last leg of the cement manufacturing process. Cement is extracted from the silo bottom by aeration and transported to electronic packing machines by air slides and bucket elevators. Cement is packed in 50 kg packs, and HDPV bags or paper bags are used as per the customers’ requirement. Electronic packing machines are calibrated to deliver the correct weight.
The constant demand of good packaging material for cement gives way to two industries – the technology developers for automation of packaging and packaging material industry. According to a study conducted by the Data Bridge Market Research, the global cement packaging industry is expected to grow at a rate of 3.4 and from 2021 to 2027. This growth shall be credited to the increasing demand from construction industry, surging application of paper bags as it provides ease of printability and replacement of conventional plastic bags. On the other hand, evolution of advanced products will further create new and ample opportunities for the growth of cement packaging market in the above-mentioned forecast period. This will also be seen in the sustainable packaging solutions vertical over the years to come as that demand is growing in most sectors related to cement.
Standards and types of packaging bags for the cement industry
The industry largely uses Polypropylene bags for packaging of cement as it offers protection from moisture and strength to packaging. There are various categories of polypropylene bags available with coatings, linings etc. PP plain woven bags are simple bags made out of plastic and stitched together with to hold cement. The next type is PP lined bags that have an extra lining of plastic in the inside which protects cement from coming in contact with moisture. Next, are the laminated PP bags that have an extra layer of poly film on them. Their strength is higher than simple woven bags and provide greater resistance to air coming in touch with cement. They also give way to bigger branding and storing of cement in uncovered storages.
The higher quality in laminated bags is the BOPP laminated bags. BOPP stands for Biaxially Oriented Polypropylene. It is a layer that is added as an extra layer to the PP woven bags to enhance its strength. BOPP laminated bags have higher durability and are attractive and durable. These bags are primarily used to store and transport multiple contents, including grains, animal feed, and fertilizers.
PP Woven bags have various advantages when put in use for storing cement. They are highly chemical and weather resistant. They have high tear strength, which enables it to carry heavyweight materials. PP woven bags are 100 per cent reusable and have high durability making it the less pollutant product compared to other packaging bags.
Quality control for cement packaging is very important. The BIS (Bureau of Indian Standards) has set norms for cement packaging. As per Cl 9.2 of IS 455: 1989, the average net mass of cement per bag shall be 50 kg. The average net mass of cement per bag may also be 25 kg subject to tolerances and packed in suitable bags as agreed to between the purchaser and the manufacturer. Similarly, as per Cl 10.2 of IS 1489 (Part 1): 1991 and IS 1489 (Part 2): 1991, the average net mass of cement per bag shall be 50 kg. The average net mass of cement per bag may also be 25 kg subject to tolerances and packed in suitable bags as agreed to between the purchaser and the manufacturer. Also, as per IS 8112: 1989, the average net mass of cement per bag may also be 25 kg, 10 kg, 5 kg, 2 kg or 1 kg, subject to tolerances and packed in suitable bag as agreed to between the purchaser and the manufacturer.
The history of cement bags has seen advancement and evolution. Up to 1970s, all cement bags used to be made of jute, which had zero moisture resistance and was prone to high spillage during handling and transportation. Since then, the switchover has been to plain woven polypropylene (PP) sacks. To upgrade PP bags, the concept of lamination was introduced which came with increase in packaging and handling cost. Some manufacturers are also using BOPP laminated bags to enhance brand value.
The technology of cement packaging
The process of cement manufacturing is incomplete till the end product i.e., is packed in bags and is ready to be shipped out. This process takes place with the help of machine and equipment in an automated process. They are mainly used to complete the automatic packing of cement and other powder materials with good fluidity, such as fly ash, gypsum powder, cement additives, etc.
These machines can be classified as a fixed type and rotatory type. The fixed type usually has 1-4 cement discharging nozzles. The rotary type includes 6-14 nozzles and operates in a rotating way to realize the automatic cement bag filling.
With this machinery, cement bags are filled continuously through the discharging mouth by the impeller running at high speed. A weight is set for the filling and when the cement reached that set weight, a signal is transmitted to the main system and the filling is stopped. This process is electronically controlled; however, bags of the desired size are manually fed to the machine.
Automation of the bag filling process has various advantages like having a stable operation, giving uniformity and structure to the bags, clean and hygienic filling of cement bags, ease of maintenance and lesser mechanical faults.
Challenges faced by users of cement due to cement packaging
Karan Sabhlok, Director, Kamdhenu Realities says, “one of the major challenges we face is when the labour unloads the packages of cement using hooks which leads to tearing of the packages and further lead to spillage of cement. We buy 50 kg packs and while loading and unloading the cement falls from packages and the rest in the pack gets hard and due to coming in contact with air, the strength of cement also decreases”.
He suggests that, “Cement should be packed in 2 bags, outer bag on which we will attach the hook and the inner bag which should be of at least 50 microns so that it keeps the cement safe from air. Also, the hook on the outer bag should be attached near the stitching so that there is least amount of damage to the bag”.
Some of the common challenges that users of cement like construction workers and builders face are wastage, leakage and tearing of cement bags while handling them. They are looking for cement manufacturers to provide stronger packaging materials or provisions where hooks can work without causing damage.
Throwing some more light on the challenges faced by builders Raj Kamal Yadav, General Manager – Strategy, Lodha Group says, “Cement industry uses unlaminated polypropylene bags with valves which allows them to pack cement very easily and fast, Since the bags are without lamination so cost of bags is low. However, the use of hooks in their logistics during the loading and unloading of cement causes tearage and leakage. These bags also have lower UV resistance and when placed in sunlight leads to cement losing its strength”.
These issues direct the cement packing industry to strive for innovation in packaging that can lead to lesser wastage and more ease of use.
Cement packaging taking a sustainable route
Cement manufacturers are moving towards paper packaging and makers of packaging are trying everyday to make cement packing material better for the environment and sustainable. While innovations are on the way, it is imperative that the environment is protected from the waste that may happen with used plastic bags.
Alpesh Patel, Managing Director, Knack Packaging says, “Every cement manufacturing company must ensure that used cement bags must be collected and either sent back for recycling or must be used as fuel in their kilns. This way they prevent waste accumulation in the ground and reduce the usage of natural resources for fuel supporting the environment.”
It is a question to dwell upon if the industry shall lean towards paper packaging that is recyclable, better in aesthetics, supports branding and is cost effective but does not protect cement well enough from environmental factors like moisture or they shall lean towards plastic sacks that do protect cement from moisture but produce larger amount of dust and are more prone to leakages.
Kanika Mathur