Middle level talk about cost reduction

Reducing costs begins with the heart, improving quality and increasing efficiency. Since the Group vigorously implemented the work of reducing costs and increasing efficiency, the companies and units have quickly unified their thinking, improved their awareness, strengthened their confidence, and focused all their energy on doing a good job, changing from "good days" to "tight days", and gathered a strong force of sharing risks, sharing aspirations and overcoming difficulties together. In this issue, the topic of "Middle Level talks about cost reduction" shares the characteristic practices and work results of Yan Xuejun, director of the energy and power plant of Hebei Xinda Iron and Steel Group Co., LTD.

To reduce costs and increase efficiency, we should pay attention to "reducing key points and managing breakthroughs", closely focus on the key points, difficulties and key points of cost control in each link of production, innovate management ideas, and deeply dig the internal potential. In the face of severe market pressure, Hebei Xinda Iron and Steel Group Co., LTD. Energy power plant fully improve the political position, careful arrangement and deployment, solid practice of the group's "strong base solid intelligent lean innovation efficiency brand strong enterprise" theme, reduce costs and increase efficiency as one of the ways to promote the development of the group, management, cost reduction, efficiency improvement, Actively explore the new space of cost reduction and efficiency, mobilize the strength of all staff, riveting the aggressivity and tenacity of "stepping stone to leave impressions, grasping iron to have marks", constantly open up the constraints of cost reduction and efficiency, and inject new vitality and new momentum into the high-quality development of Xinda!

Avoiding peaks and valleys is the main measure to reduce the company's electricity costs. According to the implementation of peak-Ping-valley differential electricity price in Hebei Power Grid, the difference between peak and valley price is very large, and the peak price is nearly three times higher than the valley price, especially in summer, the peak price is nearly four times the valley price. In order to further explore the potential to reduce the cost of efficiency and reduce the company's electricity costs, the energy and power plant with the production department to increase power management, according to the actual situation of the company's current production, some processes to avoid the peak on the valley production. Each branch plant is required to arrange maintenance in the peak section, make full use of material storage and energy storage equipment, prepare materials, water supply, reverse transport, dredging and other work are carried out in the valley section, intermittent operation of equipment, and maximize the implementation of peak avoidance valley. Using the peak and valley electricity price policy to avoid the peak and valley, arranging production during the power valley period, can not only use more electricity, but also optimize the allocation of power resources and reduce enterprise costs. From January to June 2023, all units implemented peak-avoidance valley to save electricity costs of about 4,882,600 yuan.

The energy and power plant actively carries out rationalization proposal solicitation activities, strengthens the cost awareness and saving consciousness of employees, and converts the insights hidden in the usual work into benefit results. From January to June 2023, the energy and power plant completed 174 independent improvements and 20 project improvements, of which the project improvement cost reduction and efficiency increase amount of 2,358,300 yuan.

Water treatment section regulation pool sewage lifting pump and vacuum tank independent improvement, saving spare parts cost of about 19,400 yuan; The damage of the shell of the mud pump in the mud pressing room affects the mud pressing. Through the self-repair of maintenance personnel, the spare parts cost is about 14,000 yuan; The anti-corrosion paint on the inner board of the gas cabinet burst. After on-site investigation and problem investigation, we independently purchased wire brush, rolling brush, paint and other tools and materials, completed the improvement task with quality and quantity, and saved the maintenance cost of about 11,000 yuan; During the maintenance of the unit, the internal debris cleaning of the steam generator, the chemical and physical cleaning of the stainless steel pipe scaling, the circulation water volume is increased, the surface of the condenser stainless steel pipe is cleaned, and the heat transfer effect of the condenser is greatly improved. The daily increase in electricity is 25,000 kWh, and the monthly effect is about 390,000 yuan.

Qian 'an Xinda Logistics Co., LTD. Repair shop, Hebei Xinda Mining Group Co., LTD. Whitecash crushing workshop power supply originally by Qian 'an City Mu Changkou Town electric power supply, due to the impact of the overhead line length and other external factors, the safety factor of electricity consumption is low. In order to solve this problem, the energy and power plant set up a project research group, in line with the principle of cost reduction and efficiency, the use of project surplus cables to independently complete the cable laying work from Jinfeng switch station to the filling station, reuse the waste 10KV overhead line dismantled before, from Jinfeng filling station to the east side of the energy and power plant substation to do overhead line work. During the period to overcome the adverse factors such as high temperature, crossing the river, it took 10 days to successfully transfer the electricity to the power supply substation of the energy power plant of Hebei Xinda Iron and Steel Group Co., LTD., eliminating the hidden danger of electricity consumption and ensuring the production line. The relocation project will save one-time cable procurement and laying costs of about 223,000 yuan, and long-term fixed capacity costs and electricity costs of about 625,100 yuan/year.

Due to the problems existing in the steam recovery and use system of the company, the steam utilization rate of the waste heat generator unit of the energy power plant is low, so that the unit is in a low load operation state, and the effect is meager. In order to solve the problems existing in the recovery and use of steam and improve the power generation of steam waste heat units, the Energy and power plant has set up a project research group, mainly from the steam release control, pipeline transportation, steam cascade utilization, production operation management and other aspects of optimization and improvement, daily detailed tracking of the rectification progress of each restriction point, timely coordination of the difficulties encountered by all units. Through the full cooperation of the energy and power plant and each branch plant, the recovery and utilization of waste heat and steam have achieved remarkable results. From January to February 2023, the on-grid electricity of tons of steel steam waste heat will be 10.654kWh, and the on-grid electricity of tons of steel steam waste heat units will be increased to 14kwh/t in the first stage (before April 30). As of June 2023, tons of steel has been completed online power generation 13.44kWh/t, tons of steel steam waste heat monthly effect of about 953,600 yuan.

Tackle the problem of reducing the power consumption of tons of steel

Based on the existing operation mode, the reactive power compensation power factor is controlled at 0.9-0.95 and the target is 0.92-0.95.

In terms of the operation optimization of frequency conversion facilities, the operation status of existing frequency conversion facilities in each process is comprehensively investigated, and the frequency conversion parameters are gradually optimized under the premise of meeting the process production needs, and the frequency converter is controlled at ≤45Hz; The frequency conversion facilities that have been installed and are not normally put into operation shall be put into operation in time; Fan type frequency conversion facilities, fan inlet and outlet damper in 100% normally open state to reduce the fan system operation resistance.

In terms of equipment start-stop optimization management, on the basis of the original energy-saving start-stop measures, the energy-saving start-stop time is refined according to the interval of 0.5, 1, 2, 3, 4 hours, and the pursuit of maximizing energy saving benefits.

Process production water temperature control, according to the process production water temperature requirements, reasonable control of the cooling tower fan open, reduce power consumption.

The energy and power plant sorts out the measures to reduce electricity consumption in other processes, and the electrical equipment can be reduced. The heat pressure recovery of furnace top, the operation efficiency of BPRT units of blast furnaces, the internal leakage of pressure regulating valve group and bypass valve are paid special attention. The optimization of sintering ring cooling waste heat recovery can reduce the power consumption of sintering process; High power consumption in steelmaking and refining, optimization of circulating pump operation, reducing operating load in the state of refining shutdown.

Management optimization is expected to be completed before September 30, 2023, with the goal of reducing power consumption by 5kWh/t per ton of steel, the unit price of purchased electricity is 0.52 yuan /kWh, and the monthly power consumption of tons of steel can be about 2.046 million yuan, and the annual efficiency can be about 24,552,000 yuan.

Research on reducing nitrogen consumption of tons of steel

Control of high nitrogen consumption in the ironmaking process: the spare nitrogen at the top of the blast furnace is mainly used for the sealing of the furnace top gas-tight box and the furnace top gas-tight box. The maximum design flow rate of nitrogen in a single furnace top device is 1100m³/h, the contact pressure is 0.6MPa, and the nitrogen consumption of the furnace top device is high. After calibrating or verifying the temperature, flow and pressure instrument of the furnace top equipment to meet the testing requirements, the nitrogen amount can be controlled reasonably and the nitrogen consumption can be reduced.

Purge the residual gas in the front section of blast furnace hot blast furnace to avoid internal leakage of liquid ball valve.

Nitrogen for coal injection in blast furnace is used to speed up the operation of all coal injection air compressors and reduce nitrogen consumption. Oxygen content control in coal spray bin and coal grinding according to oxygen content reasonable control nitrogen amount; Coal injection powder collector check pulse valve leakage; Reasonable control of nitrogen pressure for coal injection to prevent nitrogen overpressure release.

Controlling the high nitrogen consumption in the steelmaking process: the evaporative cold nitrogen pressure in the steelmaking plant is unstable and high, and the nitrogen consumption is large; The nitrogen quick cutting valve of converter scrubber is not automatically controlled. After blowing, the temperature of molten steel is high, and nitrogen gas is used to cool down.

In other nitrogen processes, the process equipment and facilities are sealed with nitrogen medium, the nitrogen pressure is reasonably controlled, the operating medium is not more than 30KPa, and the operation test can be done if necessary; Gas pipe network and facilities purging replacement scientific calculation of purging time, timely shut down after passing the test to avoid overblowing.

Management optimization is expected to be completed before September 30, 2023, with the goal of reducing nitrogen consumption by 5m³/t per ton of steel, the unit price of nitrogen 0.1 yuan /m³, and the monthly efficiency of nitrogen consumption per ton of steel can be about 330,000 yuan, and the annual efficiency can be about 3.96 million yuan.

"Rivers to the sea, no words far, eagle eagle sky is afraid of high", cost reduction and efficiency is the eternal theme of enterprise development. Hebei Xinda Iron and Steel Group Co., Ltd. energy power plant will continue to take advantage of the trend, in-depth implementation of the group's work deployment to reduce costs and increase efficiency, adhere to lean management guidance, promote capacity improvement, strengthen energy conservation control and do not relax, rise to the difficulties, work hard, solid work style, with practical actions to show the "pillar, withstand" responsibility, Go all out to make greater contribution to the high-quality development of the company!