Key Takeaways & Executive Findings
- •• • The standard (GB/T 45015-2024) is the first national standard for titanium gypsum resource utilization, filling the technical specification gap and providing clear pathways for building material use and ecological restoration, which is critical for increasing the current utilization rate of only ~10%. • • Titanium gypsum production in China reached 3,120×10^4 t in 2023, with over 60% concentrated in Shandong, Sichuan, and Guangdong provinces; the standard's implementation is essential to manage this large waste stream. • • The standard specifies limits for soluble impurities and pollution control indicators, addressing the high free water content (>25%) and fine particle size (<50 μm) that previously hindered utilization and caused environmental risks. • • By standardizing utilization methods and environmental risk controls, the standard supports the industry's shift toward co-production and circular economy models, as exemplified by projects like the 60×10^4 t/a cement retarder facility using titanium gypsum.
Abstract
To facilitate accurate understanding and implementation of the provisions in the Technical Specification for Comprehensive Utilization of Titanium Gypsum (GB/T 45015-2024), and to promote technological capability in comprehensive utilization while effectively controlling environmental risks during utilization, this paper analyzes the current status and existing problems of titanium gypsum generation, management, and utilization technologies in China. The standard is systematically interpreted. It is concluded that the implementation of this standard will promote resource utilization of titanium gypsum, foster energy conservation and carbon reduction in the titanium dioxide industry, and further safeguard ecological and environmental security. China produces over 3,120×10^4 t of titanium gypsum annually (2023), yet its comprehensive utilization rate is only about 10%, far lower than that of phosphogypsum (~40%) and desulfurization gypsum (~80%). The standard, as the first national standard dedicated to titanium gypsum resource utilization, establishes technical pathways for building materials and ecological restoration, sets limits for soluble impurities, and specifies pollution control indicators throughout the utilization process. It addresses the long-standing gaps in technical standards, product quality variability, and environmental supervision, providing critical support for the green and low-carbon transformation of the sulfuric acid process titanium dioxide industry.
1. Introduction
The titanium dioxide industry is a key indicator of national manufacturing modernization, with nearly 90% of China's production using the sulfuric acid process. This process generates large volumes of acidic wastewater, which is neutralized with alkaline agents, producing titanium gypsum—a byproduct primarily composed of calcium sulfate dihydrate. Despite its potential as a resource, titanium gypsum has a comprehensive utilization rate of only about 10%, significantly lower than phosphogypsum (~40%) and desulfurization gypsum (~80%). The primary obstacles include its fine particle size (often <50 μm), high free water content (>25%), and elevated iron impurities (Fe2O3 4-15%), which complicate its use in construction materials and other applications. Moreover, the lack of clear utilization pathways and environmental risk control standards has led to widespread stockpiling, with cumulative stockpiles exceeding 2×10^8 t, causing land occupation, soil contamination, and groundwater pollution.
To address these bottlenecks, the Chinese government has progressively established a policy and regulatory framework for bulk industrial solid waste management. The release of the national standard GB/T 45015-2024 on November 28, 2024, marks a pivotal step. This standard systematically defines technical requirements for titanium gypsum utilization across multiple scenarios, including building materials and ecological restoration. It introduces, for the first time, limits on soluble impurities and comprehensive pollution control indicators for the entire utilization process. By providing clear technical guidance and environmental safeguards, the standard aims to unlock the large-scale utilization of titanium gypsum, thereby supporting the green and low-carbon transformation of the titanium dioxide industry and contributing to the 'dual carbon' goals.
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ZHANG Dongqi, HE Yi, XU Jie, QI Xiangzhao, LI Li, CHEN Gang (2026). Interpretation and Implementation Recommendations for the Technical Specification for Comprehensive Utilization of Titanium Gypsum (GB/T 45015-2024). Chinese Journal of Environmental Engineering. https://doi.org/10.12030/j.cjee.202506010
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Frequently Asked Questions
What are the key technical parameters specified in GB/T 45015-2024 that address the high free water content and fine particle size of titanium gypsum?
The standard specifies limits for soluble impurities and sets pollution control indicators for the entire utilization process. While the text does not provide exact numerical limits, it requires that titanium gypsum used in building materials or ecological restoration must meet specific criteria to ensure environmental safety. The standard also mandates monitoring of pollutant emissions and provides methods for determining calcium sulfate dihydrate content (Appendix B). These provisions aim to mitigate the challenges posed by high free water content (>25%) and fine particles (<50 μm) by ensuring proper treatment and quality control.
How does the standard address the scalability of titanium gypsum utilization, given the current low utilization rate of ~10%?
The standard establishes clear technical pathways for utilization in building materials (e.g., cement retarder, gypsum-based products) and ecological restoration (e.g., soil amendment, mine backfill). By providing standardized methods and environmental risk controls, it reduces uncertainty for industries, encouraging investment in large-scale projects. For instance, existing projects like the 60×10^4 t/a cement retarder facility demonstrate feasibility, and the standard is expected to accelerate adoption across the industry.
What are the environmental risk control measures in the standard, and how do they prevent contamination during utilization?
The standard includes provisions for pollutant emissions, monitoring content and frequency, and packaging, labeling, storage, and transportation. It requires that soluble impurities and heavy metals be controlled to prevent leaching into soil and groundwater. Specific limits are not detailed in the abstract, but the standard aligns with existing environmental regulations, ensuring that utilization processes do not introduce new risks.
How does the standard align with existing industry standards like JC/T 2625-2021, and what gaps does it fill?
JC/T 2625-2021 set product quality requirements for titanium gypsum but did not specify utilization pathways or environmental risk controls. GB/T 45015-2024 complements this by providing a comprehensive framework for utilization, including technical methods and pollution control, thus filling the gap that limited large-scale application. It also connects with other standards to ensure consistency across the industry.
What are the economic implications of implementing this standard for titanium dioxide producers?
The standard is expected to increase the utilization rate of titanium gypsum, reducing stockpiling costs and potential environmental liabilities. By enabling resource recovery, producers can generate revenue from byproducts, such as cement retarder or building materials, offsetting production costs. The standard also supports the industry's shift toward circular economy models, enhancing overall sustainability and competitiveness.
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