Coal Spontaneous Combustion Prevention Project at a Port Coal Terminal

Project Overview
A coal terminal at a major port, located at the core hub of the Yangtze River Economic Belt, has six open-air strip coal yards with a total storage capacity of 1.28 million tons. It is equipped with four bridge-type grab ship unloaders, 57 belt conveyors, and five bucket-wheel stacker-reclaimers, forming a fully automated operation chain for “unloading–conveying–stacking/reclaiming”. The annual throughput exceeds 10 million tons, of which more than 60% of the imported coal is Indonesian lignite. Due to bottlenecks in transshipment efficiency within the river, the coal storage period has been passively extended to more than 60 days, far exceeding the 40-day safety threshold. This has caused the core temperature of the piles to exceed 70°C, releasing H₂S gas and accumulating hidden dangers of spontaneous combustion. This risk is further catalyzed by the combination of heat storage during sea transportation and closed transportation along the Yangtze River, leading to:
Transportation hazards: CO concentration in the closed cargo hold exceeds 2,000 ppm, and signs of spontaneous combustion have already appeared during the Yangtze River transportation stage, posing a fire risk.
Vicious cycle: Annual expenses for extended storage exceed 10 million yuan; spontaneous combustion causes loss of coal calorific value, accompanied by pressure from environmental penalties.
Turnover dilemma: Spontaneous combustion risk → shipping refusal → prolonged storage period → risk escalation, forming a systemic negative cycle.

Governance Plan
In response to the full-chain risk at the port — “heat storage during sea transportation → overdue storage → spontaneous combustion during Yangtze River transportation” — this plan adopts a dual-track technology of oxygen suppression at the source and physical isolation to break the inevitability of spontaneous combustion. The specific implementation path is as follows:
Blending coal oxygen inhibitor during loading
At the stage of loading coal into the ship’s hold, a coal oxygen inhibitor is blended in to suppress the coal-oxygen binding activity through molecular penetration. Two flexible adaptation options are provided:
Option 1: Independent blending device — The device is standalone and can perform blending before loading. Initial transformation costs are low, but later operational efficiency is low.
Option 2: Belt-conveyor retrofitted blending device — Modified on the belt conveyor system to enable blending during the loading process, with high operational efficiency.
Auxiliary measures: After loading is completed, a sealing material is sprayed on the coal surface to form an oxygen-isolating film of more than 2 mm, resisting rainwater erosion and inhibiting surface coal oxidation and temperature rise.