The cement industry is the cornerstone of the national construction industry. Few construction projects can be designed without cement. Against the background of economic recovery, the growth rate of global cement demand is on the rise, especially in the United States, China and some countries in Europe. In 2018, the global cement output reached 4.1 billion tons. The U.S. cement production accounts for 88.5 million tons, with its clinker production rising to 77.7 million tons. As we know, China and India are two big cement producers around the world. By 2018, China’s cement enterprises had grown to 3,509, with the cement industry revenue 459.8 billion yuan, up 21% year-on-year. Profits reached 33.36 billion yuan, up 248% year-on-year. This shows that the cement market still has great potential.
Cement is a product of low unit value but heavy weight, with an obvious sales radius. The freight accounts for a higher proportion of its selling price. According to different geographical locations, the sales radius of some large and medium-sized cement factories can even reach more than 500 kilometers. Therefore, limited by the radius of the cement sales market, the competition between enterprises is mainly shown in the regional scope. However, for some remote areas or inaccessible areas, the mini cement plant is clearly a better choice for investors.
Benefits of Building a Mini Cement Plant
Large and medium-sized cement plants have some common characteristics, such as advanced production technology, low production cost and large sales market, while small cement plants have relatively less obvious advantages. But this does not mean that running a small scale cement plant will not be profitable. After all, they target different markets. In general, the site selection of large and medium-sized cement plant will consider the following factors:
- The high consumption and demand for cement in the region necessitate large-scale cement production.
- Near the place of raw material production or there is a large amount of raw material deposition（limestone, fly ash, etc.）
- Completed infrastructural facilities, such as fuel, electricity and transportation systems.
- Transportation costs are relatively low.
Besides, there are many areas that only suitable for small scale cement plants, such as:
- Some developing countries and island countries. Their aggregate demand for cement is limited and can be met by setting up their own cement industry, which independent of imports.
- Large countries with low population density and low per capita cement demand. It is a good choice for them to set up their mini cement plants.
- Some areas where limestone deposits are scattered and local natural resources cannot support the daily production of large cement plants, but smaller cement plants can make use of them.
- Mountainous areas and remote areas. Because of the local infrastructure constraints, large cement plants cannot be built in these areas. Small cement factories can meet the local construction need and bring profits.
- Some labor-intensive areas.
If you set up your mini cement plant in these areas, it will not only meet the local construction needs and provide a lot of jobs but also bring you huge profits. First of all, the mini cement plant does not need a lot of investment. Its construction cycle and cost compared with large and medium-sized cement plants are much lower, and the investment returns faster, suitable for the smaller entrepreneur. Secondly, the resource exploitation quantity is small, making it easier to find large enough mines near the plant to reduce the raw material transporting cost. Moreover, because of its small sales area and low transportation costs, it satisfies a large number of customers who want to avoid large producers and obtain a more stable source of cement in terms of price and quantity. In addition, the permits and licenses for small cement plants are easier to obtain than for large plants. If you have a suitable environment and enough money, the mini cement plant is a good investment choice.
What Should You Do before Building a Mini Cement Plant
When you decide to start a mini cement plant, you need first to go with a series of investigations. The most basic is supply and demand, that is, whether there is enough local cement production demand. Then you should consider your money. Do you have enough money to set up a small scale cement plant with a certain output? If neither of these is a problem, what kind of cement do you want to produce is the next important thing you should focus on because it refers to what raw materials are there around the plant (volcanic ash, blast furnace slag, fly ash, limestone, high-grade limestone, etc.) and whether these resources meet the production standards of cement. In normal conditions, the limestone mine had better not exceed 200 kilometers away from your plant, otherwise, it is not convenient to transport. After that, you need to choose the type of fuel to be used, such as coal, gas, etc. Generally speaking, if there is no need to import, coal is the most suitable choice. Besides, the steady and sustainable supply of fuel, electricity and coal and the acquisition of environmental and production licenses are also important. Every country has different conditions and standard, we need to decide according to the specific case.
Mini Cement Plant Construction
How to define the mini cement plant? It seems that we do not have very strict regulations on it at present. Normally, its daily output is no more than 1,000 tons, and it is not much different from the production process of large and medium-sized plants, all of which need to go through three main production processes: raw material preparation, clinker calcining, and cement grinding. The three production processes involve multiple specific processes and refer to a lot of cement equipment.
Crushing Mill &Grinding Mill
Limestone, clay and iron ore are the raw materials for cement production. After mined from the quarry, they will first go into the crusher to be broken into pieces of no more than 15mm. For the small cement plant, we usually adopt single-stage crushing or double-stage crushing. The single-stage crusher refers to TPCD or PC hammer crusher, which is suitable for raw materials with medium hardness and brittleness, has a large crushing ratio, simple structure and high production efficiency. But if the daily output of cement production exceeds 100 tons, we should consider adding a jaw crusher after the hammer crusher to form a double-stage crushing. It should be noted that the jaw crusher is only suitable for materials whose compressive strength limit is less than 250mpa. In addition to these models, there are many other crushers available according to different conditions or for different raw materials, such as cone crusher, impact crusher, etc. After the crushing is finished, we should mix those raw materials in a certain proportion to meet the composition requirements of cement clinker, and then use a cement grinding machine to further grind the raw meal until they reach the specified size. Due to the clay and other raw materials contain a certain amount of water, so the LM cement vertical mill and ball mill which merge drying, grinding and blending into a single is the most frequently used machines in the cement production line.
Cement kiln is the main equipment for the second process clinker calcining. The outside kiln body is made of YZG35CrMo and 42CrMo high-temperature resistance steel. The inside is covered by superior quality refractory materials to ensure a great concentration of temperature. The working part of cement kiln is divided into preheating zone, heating transition zone, sintering zone and cooling zone. All the raw materials need to be heated at 1450 ℃ in the heating transition zone to produce chemical reactions with each other, and finally form granular clinker in the sintering zone. After the hot clinker is transported out of the kiln head, it will immediately enter the cooler placed behind the kiln head for further cooling. The whole calcination process of clinker is not completed until the temperature is reduced to normal. Generally, the rotary kiln of mini cement plants needs to adopt the machine with small occupation, low energy consumption and stable operation to ensure the continuity of production. AGICO provides cement kilns customization service. We can customize the cement kiln with different outputs and different types according to the specific needs of customers.
The diameter of clinker particles is usually between 0.32 and 5.0cm, while the finished cement we use daily is a finer powdery object. Therefore, in the last stage of cement production, we usually use the cement ball mill system or cement vertical mill system with high efficiency separator to carry out the final grinding of cement clinker to reach the particle size of finished cement. During the grinding, 2-3% gypsum powder is added as retarder so that when cement contacts with water, its solidification speed will not be too fast. Sometimes, we also add some other minerals to obtain the desired cement performance. After all the above processes are completed, the cement will be packaged and sent to its destination.