Within ACC (China), Zhang Zhenkun's position is a clear line of technical cadre promotion: Jiangxi Yadong Cement factory director, chief deputy general manager and director of the preparatory office, general manager; then concurrently general manager of Sichuan Yadong, Hubei Yadong and Huanggang Yadong; then deputy chief executive officer and technical director of ACC (China); On May 10, 2022, he was promoted to CEO, with overall responsibility for the company's operations and senior management affairs, at the age of 75. On November 2 of that year, he was elected vice president of China Cement Association. His
position is changing, but what he does has not changed-production technology and research and development have always been his areas of responsibility.

II. 12 short kilns: Make the "a la carte" configuration into an industry sample
. Asian Cement (China) has laid out 12 large-scale new dry short kiln production lines in mainland China: 10 KHD Φ4.8 × 52m, designed clinker capacity of 5000 t/d, and 2 KHD Φ5. Led by Zhang Zhenkun.
This production line has three characteristics, all with a strong personal imprint.
The first is the adherence to the "short kiln" line. The domestic industry has long been accustomed to making kilns longer and bigger. A short kiln with a pipeline calciner is selected for the sub-grade slime: the apparent decomposition rate into the kiln is controlled at 95% ~ 99% and kept stable, the kiln speed is 4 rpm to achieve "thin material fast firing", the secondary air temperature and the tertiary air temperature are kept at 1200 ℃ and 1100 ℃ respectively, and a good chilling cooler is equipped. The goal of this combination is not to maximize production, but to make the clinker quality stable for a long time. In the industry, "preheater production transformation" once became a common practice, but the sub-mud did not follow.
The second is "a la carte" procurement and independent planning. Asian Cement Factory has always adhered to independent planning, independent "a la carte" procurement of equipment, independent installation and commissioning. The main equipment is selected one by one according to the international famous brands, and then the equipment configuration of the follow-up production line is optimized one by one according to the actual use experience of the production line that has been put into operation. This road is slow, but the matching relationship between equipment and technology is in their own hands-every subsequent transformation does not have to wait for the supplier to schedule.
The third is the ultimate calculation of energy. The most typical one is the two-stage belt conveyor. The limestone downhill energy-saving power generation belt conveyor
connecting the mine and Jiangxi Yadong No.2 Plant has a total length of 3. It uses downhill gravitational potential energy to generate electricity with a capacity of 300 kW · H/H. The two-way curved conveyor belt between Plant
2 and the wharf has a total length of 2. It delivers clinker to the wharf at a rate of 1000t/H in the upward direction and delivers four kinds of raw materials and fuels to Plant 2 at a rate of 600t/H in the return direction. It crosses hilly terrain, adopts uphill, downhill and curve layout, and has no intermediate transfer station in the whole process, saving about 10.77 million yuan in investment; The actual power consumption is only 0.86 kW · H/t, and the annual power saving is 2.46 million kWh. Annual electricity savings 172.

Denitration. Sub-mud adopts the combination of pulverized coal low nitrogen combustion and ammonia water denitration, and NOx is less than 35mg/Nm ³ after technical transformation. The carbon monoxide produced by the anoxic combustion of pulverized coal can reduce nitrogen oxides in an anoxic environment, and can undertake 60% -65% of the denitrification task; the height of the reduction zone above the necking of the smoke chamber is more than 25 meters, and the diameter and height of the pipeline-type decomposition furnace are increased. Low nitrogen combustion plus SNCR can control NOx to be less than 75mg/Nm ³, and combined with medium-temperature medium-dust SCR, it can ensure ultra-low emission and ultra-low ammonia escape.
Separate grinding of sandstone. Sandstone containing quartz crystals is separately grinded in a sandstone mill, and then mixed with limestone powder according to the proportion and homogenized in a raw meal silo, which greatly improves the burnability of raw meal, promotes the solid-state diffusion reaction rate between SiO2 and CaO particles in the kiln, and improves the activity of C3S. The downtime of the sandstone mill is also not wasted-it is used to grind the limestone blending powder needed by the cement mill instead of slag, which reduces the cost and improves the particle distribution.
Wear resistant material. Wear-resistant ceramic roller tires and cement mill ceramic balls are put into use, vertical mills use ceramic roller sleeves and ceramic millstones, and roller presses use stud rollers, which further reduces the cost of cement production. High temperature resistant bag type dust collector is used at the head and tail of the kiln, and the dust emission is less than 15mg/Nm ³, even reduced to less than 10mg/Nm ³, so as to achieve ultra-low emission.
Quality control. Asia Cement Co., Ltd. purchases the same brand cement from the market every month for inspection, and makes a statistical analysis of the differences between the same brand and the "Yangfang Brand" cement, so as to learn from each other's strengths and weaknesses.The evaluation method is quite technical: calculate the coefficient of variation (standard deviation/average value) based on the single quality index data of each sample in the past 12 months, the smaller the coefficient of variation, the higher the score, and sum up to obtain the "cement stability evaluation index"; then calculate the "market trend evaluation index" according to the ranking of each factor in the current month, with 100 as the full level. Bulk mud and clinker shall be shipped by static measurement with an error of less than 2 ‰.
The results are written on the indicators: specific surface area 340 350 m ²/kg, particle size distribution slope value 1.00, 330 μm particle size content 57% ~ 60%, <3 μm particle size content 10% ~ 13%,> 45 μm particle size content 5% ~ 8%, The water requirement of standard consistency is 25.5% ~ 27.
Zhang Zhenkun's expectation for this set of indicators falls just outside the cement: "Cement buildings have to withstand 50-100 years, which is a permanent building." The cement produced by sub-mud has a surplus of one grade.
4. Waste heat power generation, slag and the "eight more years" mine
, if the process parameters are the routine action of technology, then the judgment of resources and costs is the test of technical vision. According to the rule, the MgO content in
limestone raw materials must be less than 1. According to this rule, Huanggang Yadong may face the disposal of 1.5 million tons of high MgO limestone every year, and its mine once piled up 4.5 million tons of waste soil and stone.
Zhang Zhenkun did not apply for a relaxation of the standard. What he did was to rectify the raw material ratio, optimize the clinker burning operation, and control the MgO content of limestone raw material in three kilns in Yadong, Huanggang, including Yadong, Hubei, at 2. As a result, the life of limestone mine increased by 8 years, the output value increased by hundreds of millions of yuan, and the mining cost decreased by 2 per ton.
The same set of ideas was also used in the mine. The geological model of sub-mud is established, and the mining of topsoil and high-magnesium and high-sulfur limestone is matched. The goal is to use high-MgO limestone as aggregate and high-CaO limestone as cement, which is the zero waste of the mine. The mine adopts one-shift production and three-shift transportation, and sets up a bonus incentive system for the number of trips, so as to realize the driverless operation of the whole mine. The mine has an annual mining capacity of 19 million tons, using Caterpillar equipment from the United States and Atlas drilling rigs from Sweden. After harvesting, the residual slope will be restored to green, and 250 mu of ecological agricultural park will be built around it. In the future, animal husbandry, fruit tree cultivation, vegetable cultivation and tourism will be developed.
Even so, Zhang Zhenkun is still restrained on the border: aggregates do make money, but "the main cement industry is still the direction they should focus on.".
the industry trough in June, When he received the delegation from China Cement Network in Yadong, Jiangxi Province, he suggested that the cement industry would "breathe" for a period of time. At this stage, enterprises should "reduce production and stop production" to find the best balance between output and comprehensive energy consumption cost.
A month later, at the "2023 China Cement Energy Conservation and New Energy Development Conference", he made this judgment more complete: "In the future, cement plants will change from" quantity "competition to" quality "competition. In the fierce competition, the survival of the fittest will be realized, and the number of cement kiln production lines will decrease year by year."

For alternative fuels, he cited the European experience: the European alternative fuel industry chain is complete, the policy is perfect, the waste classification is in place, and the alternative fuel thermal substitution rate (TSR) reaches 60%, while the domestic cement kiln line TSR is less than 2%, because the industry chain is not complete. Cement plants are facing problems such as difficult collection, high purchase price and poor substitution effect. He has also studied it carefully enough-biomass is pyrolyzed and gasified to produce biomass gas, which is sprayed into the decomposition furnace as a denitrification reducing agent. Without spraying ammonia water, NOx emissions can be less than 50mg/Nm ³, which can replace about 60% of coal. Harmful components such as potassium, sodium and chlorine remain in the residue as agricultural fertilizers and do not enter the decomposition furnace, thus avoiding system skinning and ring formation.
For carbon capture, his scheme also has the industrial flavor of "using local materials": metallurgical solid waste steel slag (CaO) is ground into fine powder to capture CO CO in industrial tail gas such as cement kilns. After being treated by special processes and special catalysts, the treated steel slag powder is used as an admixture to produce low-carbon cement. There are existing cases in China: the annual output of carbon capture steel slag powder is 300,000 tons, and the amount of CO CO capture is about 2.
In an exclusive interview with China Cement Network in 2018, he gave the price judgment: clinker 350 ~ 380 yuan/ton, cement 400 yuan/ton is a reasonable position. He also proposed that Shanghai should be adjusted from the secondary market to the first-class war zone in that year, based on the cost account-Jiangxi Yadong relies on the Yangtze River water transport, even if it is transported to Shanghai, the freight is only 20 yuan/ton.
Six, training people and "unmanned": leaving technical standards
Zhang Zhenkun's views on talents also bear the traces of front-line engineers.
Asian mud (China) has long insisted on localized training of talents. In addition to high-level talents from Taiwan, it attaches great importance to local talents from the mainland. Graduates account for about 40% of the middle and grass-roots level. His judgment is that the new graduates have strong plasticity, fast training and high awareness, and can identify with the corporate culture more quickly after learning and training, and some of them have risen to the level of assistant manager, manager or even vice president. He summed up the logic of cultivation in one sentence: "There is nothing you can't learn if you put your heart into it." Enterprises pay more attention to the cooperation between teams, rather than just cultivating individual elites. At the same time,
he put forward that "Yadong takes Ruichang as its home and Ruichang takes Yadong as its pride", and advocated that "the minor matter of colleagues is the major matter of the general manager". The timetable he gave
for the shape of the future factory is clear. In 2018, he proposed that Jiangxi Yadong would vigorously promote the upgrading of intelligent chemical plants and "strive for three years to achieve unmanned production workshops"-the three-shift system makes employees work and rest irregularly, and in the future, it will gradually realize unmanned inspection in the middle and night shifts and complete automated production. At the same time, he added a premise: "Although automation is intelligent, we will make great efforts to retain high-level talents."
This sensitivity to technological trends is not limited to the production line. At the 8th China Cement Energy Conservation and Environmental Protection Technology Exchange Conference in 2020, he talked about the comprehensive application of AI, 5G communication, big data, quantum computing, Internet of Everything, satellite positioning and other digital technologies at the end of his report, and put forward his judgment that the future work will be less transactional and more analytical, less based on experience and more driven by data; Less driven by individuals, more by teamwork; less local, more connected to global operating sites. His advice to China's cement industry is also straightforward-the current industry urgently needs overall talents with project planning and resource integration capabilities.
From a chief engineer in Hsinchu Plant in 1968 to a planner leading 12 large-scale new dry short kiln production lines; from the preparation of a 5000t/d short kiln to the active reduction of 5000t/d to 4000t/d in front of the kiln; from the gravity power generation of the downhill belt to the overall surplus of cement strength by one grade. In the past
58 years, what Zhang Zhenkun has done can be classified into two categories: making cement more economical and making cement better. The former is cost, the latter is quality, and these two things have always been two sides of the same thing in the cement industry.
His own definition of the job is perhaps more accurate than any other assessment- "a concrete building will last 50-100 years, it's a permanent building.".