Ammonia Desulfurization: Breaking the Traditional Coal-Type Barrier

For years, ammonia desulfurization was often considered a solution mainly suited to high-sulfur coal, while calcium-based systems were regarded as sufficient for low-sulfur coal. Changing environmental requirements and rising operating costs are challenging this conventional view.

As emission standards become more stringent and carbon costs receive greater attention, power plants using low-sulfur coal are also reassessing their long-term flue gas treatment strategies. Compared with traditional calcium desulfurization, ammonia desulfurization offers strong adaptability to different coal qualities and operating conditions.

The difference starts with the reaction mechanism. Calcium-based desulfurization relies on gas-solid-liquid reactions, where limestone dissolution and mass transfer can affect system performance. Ammonia desulfurization is based primarily on gas-liquid reactions, allowing sulfur dioxide to react rapidly with ammonia and reducing the risk of reaction-rate limitations.

Advanced ammonia-based systems can maintain desulfurization efficiencies above 95% across low-, medium-, and high-sulfur coal applications, while ammonia recovery rates of 97% or higher help support economical operation.

For plants considering a transition from calcium-based systems to ammonia-based technology, the benefits go beyond sulfur dioxide removal. Reduced gypsum handling requirements, lower solid-waste pressure, and the potential value of ammonium sulfate by-product can all influence the overall operating economics.

At MingSheng Environmental Protection, decades of chemical engineering experience and multiple generations of technology development have supported the application of ammonia desulfurization across a wide range of coal qualities.

The question is no longer simply whether a plant burns high- or low-sulfur coal. The more important question is whether its current desulfurization system remains the right solution for the environmental and economic requirements ahead.