US & European Cement Regulation Comparison

On September 9, 2010, new emission standards for hazardous air pollutants (HAPs) from Portland cement kilns went into effect. The new Environmental Protection Agency (EPA) rules, known as PC MACT, have a significant impact on cement production in the U.S. Some in the industry feel the new limits will be very difficult, if not impossible, to meet.

Since the early 2000s, the European Union (EU) has had in place similarly strict emission limits for cement producers. This raises the question: how do EU regulations compare with PC MACT, and what have plants done to meet emission limits?

An apples-to-apples comparison of U.S. and EU cement regulations is difficult because different units of measurement are used. A few examples:

• In the EU, particulate emission limits are measured based on milligrams per normal cubic meter (mg/Nm³) of gas coming out of the kiln. In the U.S., the measure for PM is pounds per ton (lbs/tn) of clinker.
• In the EU, mg/Nm³ is also used to measure HCl, while in the U.S. this pollutant is measured in parts per million by dry volume (ppmvd).
• In the EU, the basis for a œnormal cubic meter is dry gas with 10% oxygen at 0^oC. In the U.S., oxygen content is usually standardized at 7%, or sometimes 3%.

Some countries in the Europe set their own emission limits at more stringent levels than the EU’s specifications. Example: the EU-specified limit for PM₁₀ is 20 mg/Nm³, but Finland’s limit for this same pollutant is 10 mg/Nm³. Some EU countries have other relatively stringent requirements for compliance, such as Germany where continuous emissions monitoring systems (CEMS) are mandatory to measure mercury, PM, HCl, NO_x and SO₂.

Table 1 below shows emission limit ranges for different pollutants, set at different levels by countries in the EU.

Some of the numbers in Table 1 are based on measured values, while others are emission limits. In Table 2 below, lower ranges from Table 1 are used to compare EU regulations with U.S. PC MACT.