Vietnam's cement production technology includes rotary kiln technology, dry method, multi-stage heat exchanger tower system and calciner. Out of the 82 existing clinker production lines in the country, only 3 lines do not have calciner: line 1 of Hoang Thach Cement, X77, line 1 of Huu Nghi Cement. The total design capacity of these 3 lines is 1.45 million tons of cement/year, accounting for 1.45% of the total current cement design capacity.
Equipment in the clinker production line in Vietnam is mainly sourced from industrialized countries such as France, Germany, Japan... and from famous equipment manufacturers such as Polysius, FL.Smith, Loesche, Kawasaki ... Some lines are designed and supplied with equipment by Chinese mechanical corporations (Sinoma), but the main equipment such as the crusher system, important equipment of the kiln are manufactured. made from countries and famous firms.
Raw material processing and homogenization stage: input material warehouses of production lines are invested, installed equipment systems for mixing, homogenizing and dismantling raw materials, especially lines with a capacity of 4,000 tons of clinker/day or more. The circular warehouse system is gradually being replaced by the long warehouse system; use new generation vertical roller mills for raw material crushing and coal crushing.
The clinker smelting stage: most of the clinker kilns today are rotary kilns with 3 pedestals, only a few kilns have 2 pedestals - this is one of the advanced technologies of Polysius and the cement industry. World bamboo shoots. In Vietnam, it has been invested and used such as: kilns with a capacity of 5,500 tons/day of Ha Tien Cement Plant - Binh Phuoc, kilns with a capacity of 6,000 tons of clinker/day of Thang Long Cement Factory (Quang Ninh). Ninh).
The current clinker kilns are completely burned with coal in the smelting process, oil fuel is only used initially during kiln drying. This is a step forward in the technology of manufacturing burners in the cement industry, due to the characteristics of Vietnam's coal source with low volatile matter and short flame.
To save energy in the production process, 14 lines have installed dust collectors to recover waste heat for power generation. Although the installation of this equipment brings certain efficiency, the initial investment cost is quite large, so it has not been paid enough attention by investors. The electrical control and automation systems in the cement production lines are mostly installed with equipment of reputable brands such as ABB, Siemens…
In the future, emissions into the environment will be a matter of concern and strict control. When comparing emission targets set by Vietnam and China, there is a fact that: in the short term, cement producers in Vietnam have not actively implemented seriously and have not had a monitoring program. strictly regulated emissions. Cement corporations have proactively offered short, medium and long-term technological solutions towards the production of environmentally friendly "green" cement.
The first solution: alternative fuel - the trend is to use lower grade Anthracite coal (however, this option has the problem that the existing coal crushing systems according to the original design do not guarantee the capacity of crushing for low grade coal).
The second solution: upgrade the coal crushing system in all factories; find an alternative fuel source (AF) 100% burning Anthracite coal as at present. For example, rice husks, if there is a stable supply of 40,000 - 50,000 tons per year, can replace 10% of coal; Other agricultural wastes (such as fibers, fibers, cashew shell residues), industrial by-products (fabric scraps, leather shoes, etc.) are also a viable alternative fuel source.