GB/T 47635-2026Greenhouse gases - Quantification method and requirements for the carbon footprint of products - Cement (English PDF)

6.2 System Boundary

6.2.1 The system boundary for quantifying the carbon footprint of cement products includes the raw material production stage, the raw material transportation stage, and the product production stage, see [link to relevant documentation]. Figure 1.

6.2.2 The raw material and auxiliary material production stage begins with the extraction of primary resources from nature and ends when the raw materials and auxiliary materials arrive at the cement plant, including raw material production (such as...). Limestone mining, silica-alumina raw material mining and processing, correction raw materials, gypsum, mixed materials, etc., and auxiliary material production (such as packaging material processing).

6.2.3 The raw material transportation stage begins when the raw materials and auxiliary materials are transported from the place of origin to the cement plant and ends when they arrive.

6.2.4 The product manufacturing stage begins when raw materials and auxiliary materials arrive at the cement plant and ends when the product leaves the factory, including raw material pretreatment, raw meal preparation, Coal powder preparation, clinker calcination, co-processing, waste heat power generation, cement grinding, packaging and shipping, and in-plant transportation.

6.3 Declaration of Unit The unit for declaring the carbon footprint of cement products is "1 ton of cement product of a certain strength grade and type". The carbon footprint of cement clinker... The unit of measurement is "1 ton of cement clinker of a certain strength grade and type".

6.4 Selection Criteria The material (energy) data in this document should comply with the following selection criteria.

a) All energy inputs (electricity, fuel, heat) must be listed;

b) Both raw materials and auxiliary materials must be listed. If they meet the requirements of

c) and d), they can be ignored.

c) Neglected individual material (energy) flows or unit processes contribute no more than 1% to the product's carbon footprint;

d) The total contribution of all neglected material (energy) flows and unit processes to the product's carbon footprint does not exceed 5%, and this contribution is not reflected in the product's carbon footprint report. This will be explained in the report;

e) Construction of infrastructure such as roads and factory buildings, manufacturing of equipment used in various processes, consumption and emissions of personnel and living facilities within the factory area. Both can be ignored.

7.1 Data Quality Requirements

7.1.1 The data and data quality shall meet the relevant requirements of 6.3.6,

6.3.8 in GB/T 24067-2024.

7.1.2 The activity data must meet the following requirements.

a) Completeness. The system should be checked for any missing unit processes or input/output substances in accordance with the data selection criteria (see 6.4). Activity data should ideally be collected from the company's production statistics for one calendar year or 12 consecutive months.

b) Accuracy. Energy and raw material consumption data in the activity data should be derived from the company's actual production statistics records. All activity data should be accurate. It should be converted to be based on the declared unit, and relevant activity data, data sources, calculation processes, etc. should be recorded in detail.

7.1.3 The carbon footprint factor meets the following requirements.

a) Representativeness. Field data or emission factor data provided by suppliers should be used first; secondly, the latest data published by the state should be used. And relevant database data that has been evaluated; finally, publicly published literature data and industry statistical recommendations are used;

b) Completeness. This should cover all unit processes defined at the system boundaries.

7.2 Data Collection and Verification

7.2.1 The following data should be collected during the raw material and auxiliary material production stage.

---The consumption of raw materials and auxiliary materials is uniformly converted into mass (t);

---Consumption of purchased cement clinker is uniformly converted to mass (t);

---The carbon footprint of the production process of purchased cement clinker;

--- Carbon footprint factor of raw material and auxiliary material production process.

Note. When the limestone in the raw materials comes from our own mine, the consumption of explosives, lubricating oil, diesel oil, etc. is collected and converted into mass (t).

7.2.2 The following data should be collected during the raw material transportation stage.

---The transport weight and consumption of raw materials and auxiliary materials are uniformly converted into mass (t);

---Transportation distance and mode of transport for raw materials and auxiliary materials. If there are multiple suppliers of raw materials and auxiliary materials, a weighted average transportation distance can be used. The weight is the transport weight of raw materials and auxiliary materials;

---Carbon footprint factors for different modes of transportation.

7.2.3 The following data should be collected during the product manufacturing stage.

---The volume, distance, and mode of transport for fuels (alternative fuels); if multiple suppliers exist, a weighted average transport distance can be used. The weight is the weight of the transported goods.

---Consumption of energy sources such as electricity, fuel (alternative fuels), and heat;

---The lower heating value of fuels (alternative fuels);

7.4 Allocation

7.4.1 During system boundary settings or data collection, if it is found that at least one unit process's inputs and outputs contain multiple products, then... Distribute the allocation.

7.4.2 The allocation method is as follows:

a) Avoid data allocation by collecting data from detailed unit processes, such as using metering or statistical data by process or time period to replace data allocation across the entire plant. Annual statistics;

b) If data allocation cannot be avoided, prioritize allocation based on physical relationships, such as product quality;

c) If physical allocation is not feasible, the economic value of the product shall be used for allocation;

d) For symbiotic products that are used repeatedly in a closed loop, no allocation is required.

7.4.3 The allocation principles for waste-utilizing materials in alternative fuels, silicon-aluminum raw materials, corrective materials, and blended materials are as follows:

a) The carbon footprint factor of the production stage of waste-utilizing raw materials such as fly ash, carbide slag, and steel slag is 0;

b) When municipal solid waste, industrial solid waste and by-products, biomass, etc. are used as alternative fuels, the carbon footprint factor during the production stage is 0.

8.2 Calculation Method

8.2.1 Method for Calculating the Carbon Footprint of Cement Products After data collection and verification are completed, the activity data will be converted into a unified declaration unit and calculated according to formula (1).

8.2.4 Product Manufacturing Stage Greenhouse gas emissions during the cement production process include the acquisition and transportation of energy consumed in production, and the combustion of fossil fuels (or alternative fuels). The greenhouse gas emissions per unit declared during the product production stage, calculated by calcination decomposition of carbonate raw materials and calcination of non-fuel carbon, are as follows: (5) Calculate and round the result to two decimal places.

8.3 Additional Environmental Information In addition to the product carbon footprint quantification results described in section 8.2, other relevant important information should be described in the supplementary environmental information section, such as through... Non-fossil energy and green electricity consumption purchased and used through market-based transactions, etc.