With restrictions imposed on natural river sand, production of manufactured sand (m-sand) is set to grow on the back of strong demand and in view of its good quality. About 50 percent of the demand is coming from the road construction, followed by other core construction and real estate sectors. The upcoming nuclear power plants, for instance, are estimated to require 12MT of sand. With emphasis on creating sustainable projects, demand for quality sand meeting specific grades is also set to rise.
Manufactured sand is produced with the desired particle shape, gradation, silt content and absence of deleterious materials, through crushing and washing. Most importantly, its consumption will reduce cement usage in projects by 5-6 percent. As demand escalates, producers are assuring consistent supply to jobsites and as per the specifications, using the latest, advanced equipment. On their part, plant manufacturers are bringing advancements into their sand producing equipment and promoting their various features and advantages.
Puzzolana Machinery Fabricators is geared to meet demand with its Sander and Vertical Shaft Impactor (VSI) standard sand plant. “Puzzolana Sander works on floating shaft principle. Its main advantage is that it works on gyratory motion which is similar to that of the cone crusher, with a higher reduction ratio, ensuring high productivity of sand at a low operating cost. The Sander can be installed in a crushing plant as a standalone unit to produce sand. It eliminates the need of classification as the micro fines generated are within the permissible limits of IS 383 Zone II. The VSI sand plant works on the principle of continuous feed in closed circuit, similar to that applied in the production of natural river sand, using rock on rock collision for crushing, whereby a rock lined rotor acts as a high velocity pump, hurling a continuous rock stream into a tightly packed rock lined crushing chamber. The VSI does not require water for sand production and no dust is generated,” informs Rajen Khoda, group business development advisor, Puzzolana Machinery Fabricators.
He adds, “Our dry/wet classification process aims to separate the fines generated during production of sand. As we are aware, air and water aid in natural sand formation, so mechanically too, the fines considered as (–)150 microns are removed by wet or dry process to bring the sand produced within the zone levels specified in IS 383 for proper mixing in concrete.”
Propel Industries is providing the standard VSI and the more advanced configuration of jaw-cone and fine cone (the Sandmaster), which reduces 15-20 percent cost of operations, according to Senthil Kumar, MD, Propel Industries. “In the Sandmaster, the cone crusher that produces aggregates can be converted for producing m-sand by simply changing the concave mantle with a simple push of the button. This flexibility is a unique benefit as it enables plant operators to get optimum results,” he informs.
Propel’s wet Hydrocyclone and air classifier systems (dry process) help removes fines for producing m-sand. Avers Senthil, “Our crushing plants and washing systems are benchmarked on international standards for optimum production, with about 20 percent more output than competitor’s offerings. The superior quality of our products has enabled us to retain our foothold in the existing business, so much so that almost 99 percent of our m-sand business is being driven by our existing customers.”
Terex offers solutions as per the terrain, rock type and requirements with its crushing, screening, dry/wet washing, and water management systems. The Terex® TC1000 and TC1300 Autosand Cones, and Canica 2000 VSI are available in tracked, wheeled and modular platforms. For dry screening, Terex offers high frequency screens, and also wet washing, scrubbing and dewatering solutions with its T150, FM60C. The company recently launched FM120 Conexus, which has an automated control system and a small plant footprint.
Says Amol Sinha, DGM – Product Support & Training, Terex, “This is what our customers have been asking for and it is a testimony to our commitment to bring solutions that serve their needs. M-sand can be obtained from hard rocks using various technologies. We have designed our equipment to counter all problems related to crusher dump issues like oversize, moisture, ultra-fines and consolidation. For instance, to feed the materials from dump stockpiles easily and efficiently, our machines have their own hoppers; and boiler boxes fitted in the machines prevent consolidation of materials. So, the final product obtained from a Terex plant is superior in terms of size, shape and texture, all of which enhance the workability of concrete and decrease post concrete defects.”
Pointing out the benefits of m-sand, he adds, “M-sand is now accepted as a good alternative to natural sand as it does not contain any organic or soluble impurities that affect the properties of concrete. Also, m-sand can be manufactured in the nearby quarry sites, thus reducing transport cost and ensuring timely supply to the projects. India is witnessing rapid urbanization and due to the fast-growing construction industry, increased demand for river sand has led to its depletion, and subsequent ban by the government to protect the environment. In such a scenario, m-sand is the answer to our construction needs.”
Proman provides and manufactures advanced crushing & screening solutions & sand washing systems in technical collaborations with world leaders. Its crushers produce M-sand as per IS-383, conforming to concrete and plaster sand. Says R S Raghavan, MD, Proman Infrastructure Services, “The combination of our VSI and screening system has features that are flexible enough to allow us to achieve the desired variants of sand at optimum production levels. We have the technical expertise and can extend the necessary support to customers. We always strive to understand their application needs and make the necessary configurations or improvisations in our plants.”
Proman manufactures VSI in collaboration with REMco, USA; heavy-duty primary jaw crushers with the capacity to produce 100 to 500 tons per hour of aggregates; and in association with Aggregate Equipment Industries USA, it makes the unique Ortner for the removal of fines from the aggregates produced by the crushers. It also manufactures PROcone for both secondary and tertiary crushing; All these crushers come with fixed or mobile version.
According to Raghavan, Proman is a pioneer in providing systems for high cubicity aggregates, manufactured and plaster sand. The company also offers turnkey solutions to produce concrete sand, plaster sand and mortars using dry and wet processes. “In the dry process, we offer a simple, high frequency screen, or the screen with the air classifier to handle the super fines. In the wet system, our Ortner sand washer, available from 30 to 140tph, can produce a single product of washed sand at a time, while our Washed Sand Group (WSG), available from 40 to 200 tph, can produce single or two products (Plaster and concrete sand) simultaneously, and we offer the solution of thickener for the WSG to help the plant recover and save water. These solutions enable the lowest operating costs to customers,” he says.
TIL Limited – representing a strategic alliance with the Astec Aggregate and Mining Group (AAMG), a part of Astec Industries Inc. USA – offers a range of internationally acclaimed crushing & screening equipment from TIL’s state-of-the-art manufacturing facility at Kharagpur in West Bengal.
Globally, AAMG offers a complete range of dewatering and classifying tanks, coarse & fine material washers, cyclone classifiers and super scrubbers, along with dewatering screens. All these equipment are available in unit, portable, semi-portable or stationary configurations.
In India, TIL and AAMG promote the dry process of separating fines in the production of M-Sand, which is very effective in terms of productivity, cost of operations and maintenance. “The dry process with a High Frequency Screen (HFS) is less expensive with minimum operating cost, easy to maintain and does not use water,” says Raj Shrivastav, Executive-in-Charge, Crushing & Screening Solutions, TIL.
“Equipment from Astec-TIL are built for enhanced performance and energy-efficiency by way of ability to process more material in a single pass. Easily replaceable parts also make for easier maintenance and lower operating costs. The Astec-TIL High Frequency Screen is capable of higher production with more efficient sizing by way of aggressive screen vibrations applied directly to the screen media and the high RPMs allowing for the material to stratify and separate at a much faster rate as compared to conventional screens. As compared to other dry systems, such as, air classifiers, it is much cheaper to install and operate,” adds Shrivastav.
Informs Shrivastav, “There are a number of associated equipment and consumables involved in the wet treatment and production of M-Sand, which make the process expensive and complex, and the plant comparably difficult to install and maintain. For example, in the wet process, one needs a combination of log washers, cyclones, slurry pumps, thickeners, and settling tanks for the residual sludge, in addition to large quantities of water. In contrast, the Astec-TIL dry process bypasses this entire chain and also conserves water.”
Customer support & solutions
It is crucial for manufacturers to align their crushing processes with washing systems, and they must render technical support to ensure flexible operation of their plants by the users.
Informs Amol Sinha, “Terex has been investing heavily on aftermarkets and has an excellent track record of customer service to ensure smooth operation with timely supply of spare parts across India. We also keep our customers updated on the latest technologies with regular operator training programs. A dedicated training center and a rock test lab have been set up at our Hosur Facility to provide the best solutions and products.”
“Puzzolana undertakes regular and timely maintenance of its m-sand plants and washing systems as provided to its crushing units,” says Khoda.
Senthil Kumar apprises that Propel provides preventive maintenance support for its crushing and washing systems and has developed an app for customers to register their complaints and indicate parts requirement.
Shrivastav informs, “TIL extends full technical support from the concept of the plant to its supply, commissioning, aftermarket support, and maintenance & warranty services, all through its lifecycle.
As part of product support, Proman undertakes retrofitting of the plants to enable customers to produce high quality concrete and plaster sand, and cubical aggregates. Avers Raghavan, “By upgrading the plants, and with the flexibility of producing different products, we have make our customers’ production operation very profitable.”
CDE Asia’s Combo X150 Mobile Washing Plant for Superior M(Manufactured) Sand Production
CDE Asia’s Combo X150 - The newest high tech invention in Superior M-Sand ProductionA larger version of the flagship model Combo X70, the machine cleans, grades and recycles 95% water in one machine, and can produce concrete and plaster sand simultaneously
Developed specially for the manufactured sand washing market, CDE Asia’s Combo X150 washing system integrates all washing processes from end-to-end in a single compact mobile unit. The plant, with its cutting-edge technology, gives accurate control of silt cut points to deliver high-quality sand. According to the company, the plant not only maximizes production of manufactured Sand but also reduces water consumption by 95%. It incorporates a water management system, making it extremely eco-friendly. The integrated water recycling and sludge management capability enables the plant to be deployed in areas where traditional sand washing systems cannot be used, as large volumes of water and land required to operate them is readily available.
Combo requires a small supply of fresh water as opposed to traditional systems which typically consume 10-15 times more water. "This is what makes the Combo the most eco-friendly sand washing system in the world," avers Manish Bhartia, MD, CDE Asia. "The other significant advantage is the low power consumption of 0.85kW per ton of feed - at just 170 kW maximum power rating – which makes Combo X150 the most power-efficient machine using clean energy. Our innovations demonstrate CDE Asia’s commitment to help customers achieve the highest sand specifications, using washing technologies, while ensuring minimum impact on our environment."
An intelligent remote monitoring platform is also on board the Combo X150, as an option. It enables real time measurement of critical functions, storage of equipment-usage data for accurate diagnosis during service calls, and broadcast of user warnings for service requirement. It assists users in getting maximum plant performance with maximum equipment availability, such that customers can meet and exceed their production targets.
Elaborates Manish Bhartia: "The Combo X150, with its production capability of 150-200 tons per hour, provides an attractive proposition to the maturing washed manufactured Sand market in India, and is now available in over 10 countries in Asia. In fact, our washed m-sand is a preferred choice as it is a viable alternative to river sand. With the spurt in construction projects, the larger companies are regularly demanding high capacity plants to meet their sand requirement. Combo X150 provides the perfect solution in meeting their need for an integrated mobile wash system that maximizes water use. It also allows operators the flexibility to produce concrete or plaster sand simultaneously, from one machine."
The Combo X150 system can be applied for washing a wide range of materials including manufactured Sand, crushed rock fines, natural sand, gravel, etc. Due to its mobility, there is no requirement for bulky civil and structural work and the associated time-consuming process of dismantling and reinstallation. Companies engaged in quarrying in different geographic locations can move the plant as per their requirement, plus, the plant can be commissioned onsite in just less than 7 days.
A feeding system puts the feed material into the washing unit, which removes more than -75 microns fraction from the feed material. The material is then forwarded to the dewatering unit, which delivers washed, dewatered, and well-graded sand products of two grades of concrete and plaster sand via an integrated stockpile of conveyors. Waste water from the system is transferred to the inbuilt recycling unit, where the solids are separated from the water. The recycled water is circulated back into the plant and the final waste silt is removed from the recycling unit in the form of concentrated sludge for easy recovery through the integrated EasySettle sludge management system. The technology to convert sludge into light-weight bricks for construction use is also provided by the CDE TechCenter.
The new mobile Combo X150 was invented at the company’s R&D center. CDE Asia has created this entirely new marketplace across Asia with over 300 installations spread over 10 countries. “Our eco-friendly technology of producing washed and graded manufactured sand is helping developing economies to reduce their reliance on natural sand, which is fast becoming scarce and expensive. It has benefitted construction companies by providing top quality graded construction sand and sustainable operations. By utilizing normally low-value crusher fines for sand production, we can extend the life of natural resources and also add huge commercial value to our customers’ enterprises,” concludes Manish Bhartia, Managing Director of CDE Asia.