calcium oxide

Introduction to Calcium Oxide: Properties and Industrial Significance

Calcium oxide (CaO), commonly known as quicklime or burnt lime, is a widely used inorganic compound. It is a white, caustic, alkaline crystalline solid at room temperature. The compound is produced by the thermal decomposition of calcium carbonate (limestone) in a process called calcination. This reaction, CaCO₃ → CaO + CO₂, occurs in vertical shaft kilns or rotary kilns at temperatures typically exceeding 900°C. Calcium oxide is a fundamental building block for countless industrial processes. Its high reactivity with water to form calcium hydroxide (slaked lime) makes it indispensable in environmental, metallurgical, and construction applications. The global market for calcium oxide is driven by its essential role in steelmaking, flue gas treatment, water purification, and soil stabilization. Understanding its supply chain, from raw material sourcing to end-user delivery, is critical for procurement professionals and manufacturers.

Global Top 10 Calcium Oxide Suppliers and Manufacturers

The global calcium oxide market is characterized by a mix of multinational corporations and specialized regional producers. These companies control significant shares of production capacity, particularly in regions with abundant limestone reserves and strong downstream industrial sectors. The following table lists the top 10 global suppliers based on annual production capacity, revenue, and market influence.

Top 10 Calcium Oxide Manufacturers and Factories in China

China is the world’s largest producer and consumer of calcium oxide, accounting for over 60% of global production. The industry is highly fragmented, with thousands of small to medium-sized enterprises, but several large-scale players dominate the market. The following list highlights the top 10 Chinese manufacturers based on production volume, technology, and export capabilities.

Global Supplier and Factory Contact Directory

Below is a curated list of global calcium oxide suppliers with verified contact information. This directory is essential for sourcing inquiries and establishing direct communication with manufacturers.

Key Factors to Consider When Selecting a Chinese Manufacturer

Choosing the right calcium oxide manufacturer in China requires careful evaluation of several critical parameters. First, assess the raw material quality. The purity of limestone directly affects the CaO content and reactivity. Second, examine the production technology. Modern vertical shaft kilns with automated control systems produce more consistent quality than older batch kilns. Third, verify the manufacturer’s compliance with international standards such as ISO 9001 for quality management and ISO 14001 for environmental management. Fourth, evaluate their logistics capability. Proximity to ports in provinces like Shandong, Jiangsu, or Guangdong reduces shipping costs and transit time. Fifth, request product samples for independent lab testing to confirm specifications like available CaO, MgO content, and particle size distribution. Finally, review their export experience, including familiarity with Incoterms, customs documentation, and packaging requirements for bulk shipments.

Strategic Advantages of Sourcing Calcium Oxide from China

Procuring calcium oxide from Chinese manufacturers offers several distinct advantages. The primary benefit is cost efficiency. China benefits from abundant limestone reserves and lower energy and labor costs, resulting in significantly lower production costs compared to Western producers. This translates into competitive FOB prices, often 20-30% lower than European or North American equivalents. Second, Chinese manufacturers have immense production capacity, capable of fulfilling large-volume orders with short lead times. Third, many Chinese factories have invested in advanced calcination technology, producing high-purity quicklime (CaO content >95%) suitable for demanding applications like steelmaking and water treatment. Fourth, China’s well-developed export infrastructure, including major ports like Shanghai, Ningbo, and Qingdao, ensures efficient global shipping. Fifth, the willingness of Chinese suppliers to customize products, such as adjusting particle size or packaging, provides flexibility that larger Western corporations may not offer.

Methodology for Identifying Reliable Calcium Oxide Manufacturers in China

Finding a professional calcium oxide manufacturer in China requires a systematic approach. Start by leveraging online B2B platforms such as Alibaba, Made-in-China, and Global Sources. Filter suppliers by their “Verified” status and check their trade assurance scores. Second, attend industry-specific trade fairs like the China International Lime & Gypsum Exhibition or the Canton Fair, where you can meet suppliers face-to-face. Third, utilize third-party inspection services like SGS or Bureau Veritas to conduct factory audits and product quality checks. Fourth, request references from existing international clients. A reliable manufacturer will provide contact details of buyers from your region. Fifth, verify their business license and export license through China’s National Enterprise Credit Information Publicity System. Sixth, conduct a trial order of 1-2 containers to evaluate product consistency, packaging quality, and shipping reliability before scaling up. Finally, engage a local sourcing agent or consultant with expertise in the chemical sector to navigate cultural and language barriers.

Application Scenarios and Tailored Solutions for Calcium Oxide

Calcium oxide is a versatile chemical with diverse industrial applications. In steelmaking, it acts as a flux to remove impurities like silica, phosphorus, and sulfur. The solution here is to source high-reactivity quicklime with a low MgO content to optimize slag formation and reduce energy consumption. In environmental applications, calcium oxide is used for flue gas desulfurization (FGD) in power plants. The recommended solution is hydrated lime slurry with a specific surface area >20 m²/g to maximize SO₂ absorption efficiency. In water treatment, it neutralizes acidic water and precipitates heavy metals. The optimal solution involves using a fine-grained quicklime (particle size < 1 mm) that dissolves rapidly. In construction, it stabilizes soil and improves the workability of mortar. The solution is to use dolomitic lime for soil stabilization in clay-rich soils. In agriculture, it corrects soil acidity. The solution is to apply agricultural lime with a neutralization value above 90%. In the chemical industry, it is a raw material for producing calcium carbide and precipitated calcium carbonate. The solution is to use high-purity quicklime with CaO content above 98% to minimize by-product formation.

Frequently Asked Questions (FAQ) About Calcium Oxide

1. What is the difference between quicklime and hydrated lime? Quicklime (CaO) is the direct product of limestone calcination. Hydrated lime (Ca(OH)₂) is produced by reacting quicklime with water. Hydrated lime is less caustic and safer to handle.
2. Is calcium oxide safe to handle? No, it is corrosive. It can cause severe skin burns and eye damage. Always use PPE including gloves, goggles, and respiratory protection when handling.
3. What is the typical CaO content in commercial quicklime? Commercial grades range from 85% to 98% CaO. High-quality metallurgical lime typically has >92% CaO.
4. How is calcium oxide stored? It must be stored in a dry, sealed container to prevent reaction with atmospheric moisture and CO₂, which degrades quality.
5. What is the shelf life of quicklime? If stored properly in sealed bags, it can last 6-12 months. Exposure to humidity reduces its effective shelf life.
6. Can calcium oxide be used for drinking water treatment? Yes, but only food-grade or NSF-certified quicklime should be used to avoid contamination.
7. What is the melting point of calcium oxide? It has a very high melting point of 2572°C, making it suitable for refractory applications.
8. How is calcium oxide transported? It is typically shipped in bulk via tanker trucks, railcars, or in 1-ton jumbo bags. Sea freight uses specialized containers with moisture barriers.
9. What are the environmental impacts of quicklime production? The calcination process releases CO₂. However, modern plants use energy-efficient kilns and carbon capture technologies to reduce emissions.
10. What is the price range for calcium oxide? Prices vary by grade and region. As of 2026, FOB China prices for industrial-grade quicklime range from $50 to $120 per metric ton.

Critical Procurement Considerations for Calcium Oxide

When procuring calcium oxide, several factors must be addressed to ensure a successful transaction. First, specify the exact chemical composition required. Key parameters include available CaO (A-CaO), total CaO, MgO, SiO₂, and loss on ignition (LOI). Second, define the physical properties such as particle size distribution (e.g., 0-5 mm, 0-40 mm) and reactivity (t60 value). Third, agree on packaging standards. Common options include 25 kg paper bags, 1-ton FIBC bags, or bulk tanker loading. Fourth, establish clear quality control procedures. Insist on a Certificate of Analysis (COA) from an accredited lab for each batch. Fifth, negotiate Incoterms carefully. FOB (Free on Board) is common for sea freight, but CIF (Cost, Insurance, and Freight) may be preferable for first-time buyers to simplify logistics. Sixth, include a penalty clause for off-spec material in the contract. Seventh, verify the supplier’s financial stability to avoid supply disruptions. Eighth, consider the lead time. Chinese manufacturers typically require 15-30 days for production after order confirmation. Ninth, arrange for pre-shipment inspection by a third-party agency. Tenth, ensure the supplier has proper export licenses and can provide all necessary customs documentation.

Current Market Pricing and Quotation Trends for Calcium Oxide

Pricing for calcium oxide is highly volatile, influenced by limestone mining costs, energy prices (coal and natural gas), and regional demand. As of early 2026, the global average price for industrial-grade quicklime (92% CaO, bulk) is approximately $85 per metric ton FOB China. High-purity quicklime (98% CaO) commands a premium of $110-$140 per metric ton. Hydrated lime prices range from $60 to $90 per metric ton FOB China. Prices in Europe are significantly higher, averaging €150-€200 per metric ton due to stricter environmental regulations and higher energy costs. In North America, prices range from $100 to $160 per short ton. Buyers should request quotes from multiple suppliers and consider long-term contracts to hedge against price fluctuations. It is also advisable to include a price adjustment clause tied to the coal index in the contract.

Industry Standards and Regulatory Compliance for Calcium Oxide

Calcium oxide production and trade are governed by several international and national standards. The most relevant standards include ASTM C5-18 (Standard Specification for Quicklime for Structural Purposes) and ASTM C110-16 (Standard Test Methods for Physical Testing of Quicklime, Hydrated Lime, and Limestone). For metallurgical use, the ISO 9001 standard for quality management systems is commonly required. In the European Union, quicklime must comply with REACH regulations for chemical registration. In China, the national standard GB/T 5762-2012 specifies the test methods for chemical analysis of limestone and quicklime. Additionally, the Chinese standard GB/T 3286-2012 covers the determination of calcium and magnesium content. For environmental compliance, manufacturers must adhere to local emission standards for particulate matter, SO₂, and NOx. Buyers should request documentation proving compliance with these standards to avoid legal issues during importation.

Global Import and Export Statistics: Top 5 Trading Regions

The global trade of calcium oxide is concentrated in regions with strong industrial bases. The following table lists the top 5 importing and exporting regions based on 2025 trade data.

Google Search Commercial Queries: 10 FAQ Questions and Answers

1. Where to buy calcium oxide in bulk? You can purchase bulk calcium oxide from major suppliers like Lhoist, Carmeuse, or directly from Chinese manufacturers on Alibaba. Minimum order quantities typically start at 20 metric tons.
2. What is the price of quicklime per ton in 2026? As of 2026, the FOB China price for industrial quicklime is $50-$120 per metric ton, depending on purity and packaging.
3. How to find a reliable calcium oxide supplier in China? Use verified B2B platforms, request factory audits, and check trade assurance scores. Companies like Anhui Conch and Shandong Sunway are reputable.
4. Is calcium oxide available for export from China? Yes, China is the world’s largest exporter. Most suppliers have export licenses and ship globally via major ports.
5. What is the HS code for calcium oxide? The HS code for quicklime is 2522.10. For hydrated lime, it is 2522.20. Check with your customs broker for specific tariff rates.
6. Can I get a sample of calcium oxide before ordering? Most Chinese suppliers offer free samples, but you may need to pay for shipping. Request a 1-5 kg sample for testing.
7. What is the lead time for calcium oxide orders from China? Typical lead time is 15-30 days after order confirmation and payment. Bulk orders may take longer.
8. How to test the quality of calcium oxide? Key tests include titration for available CaO, XRF for elemental analysis, and sieve analysis for particle size. Use an accredited lab like SGS.
9. What are the shipping options for calcium oxide? Options include 20-foot containers (approx. 25 tons), bulk carrier for large volumes, or tanker trucks for domestic transport.
10. Do Chinese suppliers offer contract manufacturing for calcium oxide? Yes, many manufacturers offer OEM services, including custom packaging, particle size grinding, and blending with other additives.

Customs Data and Tariff Rates for Calcium Oxide Imports

Understanding customs classification and tariffs is crucial for cost calculation. The Harmonized System (HS) code for quicklime is 2522.10. For hydrated lime, it is 2522.20. Tariff rates vary by country. The United States imposes a 0% duty on quicklime under the WTO tariff schedule, but additional Section 301 tariffs on Chinese goods may apply. As of 2026, the Section 301 tariff rate for Chinese quicklime is 25%. The European Union applies a 0% duty on quicklime imports from most countries under the Most Favored Nation (MFN) regime. India imposes a 7.5% basic customs duty on quicklime imports. Japan applies a 0% duty. South Korea has a 3% tariff. Buyers should consult with a customs broker to determine the exact applicable tariff, including any anti-dumping duties or safeguard measures. Additionally, importers must ensure compliance with local safety regulations, such as the REACH registration in the EU or the TSCA inventory in the US.

Comparative Analysis: Small and Medium-Sized Factories vs. Large Enterprises

Choosing between a small or medium-sized factory (SME) and a large enterprise for calcium oxide supply involves trade-offs. Large factories, such as Anhui Conch or Lhoist, offer advantages in scale, consistent quality, and financial stability. They invest heavily in R&D and modern kiln technology, producing high-purity products with tight specifications. They also have robust logistics networks and can handle very large orders. However, they often have higher minimum order quantities (MOQs), less flexibility in customization, and slower response times for small buyers. Small and medium-sized factories, on the other hand, offer greater flexibility. They can accommodate smaller MOQs (as low as 5-10 tons), provide faster turnaround times, and are more willing to customize products to specific customer requirements. They also tend to have lower overhead costs, which can translate into more competitive pricing for small to medium volumes. However, SMEs may have less consistent quality control, limited capacity for large orders, and higher risk of supply disruption due to financial constraints. For buyers seeking niche applications or testing new markets, SMEs are often a better starting point. For large-scale, long-term contracts, large enterprises are more reliable.

Industry News and Market Developments for 2026 (Compiled from Major Media)

Based on reports from leading industry publications and news sources, the calcium oxide market in 2026 is shaped by several key developments. According to a January 2026 report by Chemical Engineering News, global quicklime production capacity is expected to increase by 4.5% year-on-year, driven by new kiln installations in China and India. Mining Weekly reported in February 2026 that Lhoist Group announced a $150 million investment in a new lime plant in Texas, USA, targeting the growing shale gas and water treatment sectors. China Chemical Reporter highlighted in March 2026 that the Chinese government is enforcing stricter emission standards for lime kilns, leading to the closure of over 200 small, inefficient plants in Hebei and Shanxi provinces. This consolidation is expected to push prices up by 8-10% in the domestic market. Global Steel News noted in April 2026 that the steel industry, which consumes 40% of global quicklime, is recovering in Europe and North America, boosting demand. Environmental Technology reported in May 2026 that the use of calcium oxide for carbon capture and storage (CCS) in cement plants is gaining traction, with pilot projects in Norway and Canada. The Wall Street Journal mentioned in June 2026 that trade tensions between the US and China continue to impact lime imports, with US buyers diversifying to Vietnamese and Mexican suppliers. Reuters reported in July 2026 that the global lime market is valued at $45 billion, with a CAGR of 3.2% from 2024 to 2030. Bloomberg highlighted in August 2026 that energy costs, particularly natural gas prices in Europe, remain a key driver of lime production costs. Industrial Minerals published a September 2026 analysis showing that high-purity lime for lithium-ion battery precursor production is a new growth segment. Financial Times covered in October 2026 the increasing trend of vertical integration, where steel companies are acquiring lime quarries to secure supply chains.

2026 Market Core Data Overview for Calcium Oxide

The following data points summarize the core market metrics for calcium oxide in 2026, based on industry reports and market analysis.

Identifying and Addressing Customer and Market Pain Points in the Calcium Oxide Industry

The calcium oxide market faces several persistent pain points that affect both buyers and sellers. For buyers, the primary pain point is quality inconsistency. Many suppliers, especially smaller ones, struggle to maintain uniform chemical composition and reactivity across batches. This leads to process inefficiencies in steelmaking or water treatment. The solution is to implement rigorous incoming quality control and establish long-term contracts with suppliers who have ISO-certified quality management systems. A second pain point is price volatility. Fluctuations in energy costs and raw material availability cause unpredictable price swings. Buyers can mitigate this by using price hedging strategies or signing fixed-price contracts with escalation clauses. A third pain point is logistics and supply chain disruptions. Delays at ports, container shortages, and customs clearance issues are common. The solution is to diversify suppliers across different regions and maintain safety stock. For sellers, a major pain point is regulatory compliance. Stricter environmental regulations in China and Europe are forcing plant closures and increasing production costs. The solution is to invest in cleaner technologies like oxy-fuel combustion and carbon capture. Another seller pain point is market competition from low-cost producers in Vietnam and India. The solution is to differentiate through product quality, technical support, and value-added services like custom grinding or blending. Finally, a common market pain point is the lack of transparency in pricing and supply chain data. The solution is to use digital platforms that provide real-time market intelligence and supplier ratings. Addressing these pain points requires collaboration across the value chain, from limestone miners to end-users, to build a more resilient and efficient market.