The industrial environmental control system at our thermal power plants covers all aspects, from incoming fuel to flue gases.
Krasnoyarskaya CHPP-3 is not the largest SGC's unit, but it regularly conducts over 30 various analyses and studies. Accredited laboratories monitor the soil, ground, river and waste water, fuel entering the plant, industrial waste and, of course, emissions into the air at SGC's power plants.
According to the schedule, laboratories take measurements using sampling devices, gas analysers and other equipment, process samples and carry out analysis. Then they compare the results obtained with the approved standards and prepare reports.
Air: to catch and measure
The first thing people care about when it comes to industrial environmental impact is air pollution. At present, accredited laboratories monitor emissions from stationary sources in line with the schedules and calculation methods approved by state authorities. Their calculations take into account the amount of fuel burnt, the characteristics of primary equipment and the efficiency of gas cleaning equipment.
They also take control air quality measurements in the company's affected area. However, this method it not the most indicative, because other emission sources may be located in the plant's affected area. As a rule, next to power plants, there are large industrial facilities. When the concentration of harmful substances is exceeded, it can be difficult to understand the causes of air pollution.
To measure the emissions at each facility, measurements should be taken directly where exhaust gases are emitted. At CHPPs, these are stacks. To this end, SGC is now installing a system of automatic instrumental online monitoring of emissions at its units.
At Krasnoyarskaya CHPP-1 and CHPP-3, an online emission monitoring system has already been installed, with sensors located right in the stacks, where gases are sampled. Preparations are underway for the installation of a similar system at Krasnoyarskaya CHPP-2. In the second half of 2021, the online monitoring system will be commissioned after calibration and trial operation. SGC's facilities in other cities are also preparing to introduce similar systems: automatic instrumental online monitoring of emissions will be available in Kuzbass, Altai, Khakassia and Novosibirsk by 2026.
Fire: fuel quality control
Environmental control at CHPPs begins with checking the quality of coal arrived at the plant. The amount of waste and emissions depends on its characteristics. While using special instruments for monitoring, laboratory analysts simulate the process of coal burning in a boiler furnace.
Ash content: the lower the better. The average ash content of Borodinsky coal at Krasnoyarskaya CHPP-3 is 8%, which is a relatively low figure. For example, the ash content of Kazakhstan coal sometimes exceeds 30%.
Moisture content: it can reach 35% in Borodinsky brown coal. Hard coal contains much less moisture.
Heat or calorific value. According to this parameter, brown coal is somewhat inferior to hard coal.
The content of volatile substances, sometimes called the gaseous component of solid fuel, can reach 48%.
Sulphur content: high quality coal should contain as little sulphur as possible, no more than 0.4%.
Krasnoyarskaya CHPP-3 burns brown coal from the Borodinsky open-pit mine. The fuel quality controllers have revealed only once a case of non-conformity to the required fuel characteristics: in 2013, a batch with increased ash content arrived. The supplier received a claim, and since then, such cases have never repeated.
Fuel research also includes heating oil, which is used for firing up boilers, and fuels and lubricants necessary for the operation of equipment.
Water: intake and discharge
All river water entering the plant is checked and processed by experts. It is important for power plant boilers that the water does not contain any impurities and gases that would corrode metal. Krasnoyarskaya CHPP-3 supplies the city with hot water of potable quality, although its treatment differs from that used to generate steam in boilers. To control the composition of water, chemical shops at each CHPP are equipped with sampling points, taps, to take water for analysis. At Krasnoyarskaya CHPP-3, this process is automated.
The plant needs water not only to produce boiling water and steam but also for condensation equipment. Krasnoyarsk CHPPs have no cooling towers to cool down the outgoing steam; the cold Yenisei takes excess heat all year round. After treatment, the river water returns back to the Yenisei. Its composition is carefully controlled at the point of water intake, discharge and 500 metres above and below the discharge point. Experts also check the efficiency of local treatment facilities.
Earth: replenishing what has been withdrawn
SUEK’s power plants actively involve ash and slag in economic activities. In 2017, all units received a positive opinion from state environmental experts regarding the production of ash and slag materials from waste generated by CHPPs. Ash and slag materials from CHPPs in Krasnoyarsk are used in land reclamation, for example, to restore worked-out open-pit mines.
The safety of the produced ash and slag materials is confirmed by numerous studies. Experts check everything, from heavy metals and harmful bacteria to radiation levels.
The production of ash and slag materials provides for increased control scope in terms of frequency, the number of control points and controlled substances.