Green Foundry: How Do We Achieve Energy Efficiency and Environmental Protection in the Casting Process for Railway Parts?

When people talk about casting, images of billowing smoke, molten iron, and dust-filled air may come to mind. This is the stereotypical impression left by traditional casting. However, in our factory, we are committed to breaking this stereotype. We firmly believe that providing strength for solid railway parts should not come at the expense of the environment. “Green casting” is not just an empty slogan for us; it is a practice and commitment integrated into every day and every process.

So, how do we incorporate “green” into this fiery steel industry?

1. Energy conservation and consumption reduction from the source

1.1 Melting is the most energy-consuming stage

Upgrade: We have phased out old, energy-intensive cupola furnaces and fully adopted medium-frequency electric furnaces. These furnaces heat metal materials through electromagnetic induction, generating heat directly within the materials, achieving extremely high thermal efficiency. Compared to traditional methods, they can save about 15% to 20% of electricity, provide uniform heating, maintain stable metal composition, and minimize burn-off, thereby enhancing product quality from the source and reducing raw material waste.

Preferred furnace materials: We strictly control the metal furnace materials entering the furnace. We no longer use scrap steel of unknown origin and high impurity content, but instead select high-quality and clean furnace materials and conduct scientific proportioning. This not only reduces the slag and waste gas produced during the smelting process but also makes the subsequent molten steel purer, lowering the energy consumption and cost of “rework”.

1.2. Recycling of Used Foundry Sand

In the molding process, sand casting consumes a large amount of foundry sand. Traditionally, the used sand was discarded as industrial waste, taking up space and polluting the environment.

We have invested in a used sand regeneration and recycling system. This system is like a “magician” in our workshop. It can break down, screen, demagnetize, cool, and remove the ineffective clay and coal powder from the used high-temperature sand blocks, restoring the old sand to its original vitality and making it suitable for molding again.

Now, over 90% of the sand used in our workshop is recycled. This not only means that we reduce thousands of tons of solid waste every year but also significantly lowers the demand for new sand, conserving mineral resources.

II. Treating “Waste Gas” and Purifying “Wastewater” to Approach Zero Emissions

Emissions are inevitable in the casting process. Our goal is not to eliminate them but to “purify” them to a level that is harmless to the environment through technical means.

2.1. Installing Gas Collecting Hoods on Smoke Sources

The smoke generated during melting and pouring is a key focus of environmental protection. We have installed gas-collecting hoods at all smoke-producing points, as if putting “masks” on the smoke-producing equipment. All collected smoke is sent through pipes to a highly efficient bag filter system.

Inside this system, there are thousands of specially made filter bags. As the smoke passes through, over 99% of the dust particles are intercepted and adsorbed on the surface of the filter bags, while the clean gas is discharged through the chimney in compliance with standards. The collected dust is handed over to qualified units for professional treatment to prevent secondary pollution.

2.2. Recycling Wastewater

Water is used in the cooling and cleaning stages of casting. We have built a complete water recycling and treatment system. All used water does not go directly into the sewer but enters sedimentation tanks and purification equipment. After processes such as coagulation, sedimentation, and filtration, the suspended solids and impurities are removed, and the water becomes as clear as before, then pumped back to the production line for reuse.

This system achieves “zero discharge” of production wastewater. We save precious water resources and eliminate the potential impact on surrounding water bodies.

III. Recycling: The “Value Rebirth” of Waste Heat and Waste Materials

The essence of green casting lies in the “circular economy”, that is, finding new value for all “waste”.

3.1. Recovering “Invisible” Energy

During the operation of the medium-frequency electric furnace, the coil needs to be cooled with water, which takes away a large amount of heat. Previously, this heat was directly dissipated into the air, wasted. Now, we have installed a waste heat recovery device to extract the heat from the cooling water, providing heating for our offices and some workshops in winter, achieving a stepwise utilization of energy. This is equivalent to “snatching” back part of the energy from the electric furnace, making every kilowatt-hour of electricity count.

3.2. The Art of Turning Waste into Treasure

In addition to the regeneration of used sand, we also classify and treat other waste materials generated during production. For example, the slag produced during melting can be processed and used as a base material for construction; scrapped castings and gates are all recycled and reused as raw materials for melting, truly achieving “zero waste”.

Our “green casting” journey is a path of innovation that respects tradition. It requires continuous financial investment and, more importantly, an enhanced environmental awareness among all employees. Every small improvement, from the recycling of a drop of water to the regeneration of a grain of sand, embodies our respect and responsibility for this cause.

Because we understand that what we cast is not only the parts that ensure the safe operation of trains but also a sustainable, green and beautiful future for our descendants, this is the responsibility and answer of a modern casting enterprise.

Supplier

Luoyang Fonyo Heavy Industries Co., Ltd,founded in 1998,is a manufacturer in railway casting parts.Our factory covers an area of 72,600㎡, with more than 300 employees, 32 technicians, including 5 senior engineers, 11 assistant engineers, and 16 technicians.Our production capacity is 30,000 tons per year. Currently, we mainly produce casting, machining, and assembly for locomotive, railcar, high-speed trains, mining equipment,wind power,etc.
We are the railway parts supply to CRRC(including more than 20 branch companies and subsidiaries of CRRC),Gemac Engineering Machinery,Sanygroup, Citic Heavy Industries,etc. Our products have been exported to Russia, the United States, Germany, Argentina, Japan, France, South Africa,Italy and other countries all over the world.