October 30, 2009 

Subject: Meeting between with Polysius Corporation (DRAFT)

Location: 180 Interstate North Parkway, Atlanta, Georgia 30339 

Date: October 28, 2009 

Participants: See attached list 

This meeting was held to discuss common areas of interest to the cement industry, the U.S. EPA, 

State regulatory agencies, and Polysius. 

I. Polysius presented background information on the company and on current projects they 

have as they relate to the cement industry and pollution control. The following is a 

summary of the key areas and points presented by Polysius. 

• Current environmental trends present the following challenges and opportunities: 

o Global warming 

o Preventing emissions of NOx and VOC 

o CO2 minimization 

• In response to these challenges/opportunities, Polysius has projects in the following 

areas: 

o Use of SNCR/SCR 

o Refitting existing plants 

o Blending cements 

o Use of new binding agents 

o CO2 capture and sequestration (CCS) 

Polysius provided an overview of their current work in the areas of controlling/reducing NOx, 

THC, and mercury. 

NOx Control

• Trends in government regulation of NOx are toward increasingly stringent standards. 

• TA-Luft, Germany’s environmental agency reduced the NOx limit down to 500 mg/Nm3 

(1.95-2.0 lb/st) by the year 2002, with an eventual goal in 2013 of 1.5 lb/st. 

Multistage Combustion (MSC)

• Able to reduce emissions from 1500 down to 800 mg/Nm3 

• Prepol MSC – utilizes two burning/reducing zones 

• MSC: 

o Reduce NOx by up to 30% 

o Fuel dependent 

o Decrease in process stability (due to sulfur and alkali) with aggressive MSC 

o Limit is about 800 mg/Nm3 (3.2 lb/st) 

• Fuel dependency of MSC 

o Need at least 32% volatiles in fuel to get good NOx removal 

o Bituminous coal, mostly east of the Mississippi River has volatiles in the range 

of32-35%. 

o Coals west of the Mississippi (e.g., lignite coal) typically have 35-40% volatiles 

and offer the potential for improved MSC performance 
October 30, 2009 

o Alternative fuels may offer improved MSC performance in the range of 200-250 

mg/Nm3. 

o In Germany, alternative fuels are allowed with the applicable regulations 

determined by the amount of alternative fuel burned. Below 25% alternative fuel, 

cement regualton apply; 25-65%, combination of cement and waste incinerator 

regulations apply; above 65%, waste incineration regulations apply. 

MSC and SNCR

• Can reduce NOx down to 500 mg/Nm3 (1.95-2.0 lb/st) 

• Performance affected by: 

o Each kiln is different (at same molar ratio (NMR), kilns perform differently 

o Concurrence of reduction and combustion 

o Secondary emissions of NH3 and CO (above NMR of 1, potential for NH3 slip; 

detached plume possible) 

SCR

• Able to reduce NOx down to 200 mg/Nm3 

• Catalyst types: 

o Honeycomb – need channel size of at least 1.5mm 

o Plate – need surface area of at least 300 m2/m3 

• Elex and Polysius - joint venture on SCR/catalyst controls 

• Interested in performing full scale demonstration of SCR with industry and/or 

government sponsorship to investigate performance in reducing NOx and VOC and 

oxidizing mercury 

• 2 plants in Germany to start using SCR in Spring 2010; 2 more SCR controlled plants 

being built in Australia. 

• Monselice, Italy SCR experience 

o 2400 tpd PH kiln 

o NOx in inlet 3.6-4.0 lb/st 

o 90% or better control with SCR 

o Each catalyst has its own dust blowing system; not always effective w/ some 

plugging 

o Catalyst taken off line every few months for cleaning 

o Catalyst running for 5000-7000 hrs 

o Goal is take catalyst down once/yr for cleaning 

THC Control

• Based on lab tests on samples of limestone from US cement companies, THC emissions 

were predicted: 

o Average was 20 ppm 

o 95% were 50 ppm or less 

o Less than 1% were 7 ppm or less 

• 2009 tests from Europe yielded similar results 

• VOC would be a preferred surrogate for organic HAP because it does not include 

methane, which can be as much as 50-60% of THC 

RTO

• Due to the low organics content of their exhaust gases, TXI Midlothian RTO is fired with 

natural gas in order to be regenerative 
October 30, 2009 

• Heat exchanger replacement occurs every 5 years at a cost of $2.75 million 

• CO2 emissions from RTO are 80,000 tpy 

ACI

• Works well on higher hydrocarbons –90% removal on C4; 70% removal on C3; 30% 

removal on C1 

• Performance of ACI on THC is problematic when the methane portion is high 

SCR

• 35-50% removal 

Mercury

• Polvitech – fixed bed active coke technology – installed on European incinerator in 1991 

o Activated coke used instead of coal; activated coke has much greater surface area 

than coal allowing smaller filter bed than possible with coal; sufficient activated 

coke not available in the U.S. 

o Designed for removal of dioxin/furan and sulfur 

o Plant burned biosolids/sewage sludge containing mercury 

o Use for mercury removal would require different bed thickness. 

o Original design burned spent coke with other fuel 

o Design for mercury control could dispose of ESP dust in order to bleed off 

mercury to reduce mercury emissions 

o Coke bed did not control methane 

• ACI 

o Option 1 – Desorption of CKD. Heat CKD with natural gas to volatilize and 

concentrate mercury in small exhaust gas stream; remove mercury with fixed bed 

coke bed; pilot trials were conducted in 1992 

o Option 2 – Add second baghouse to collect carbon and landfill or recycle 

o With both options, concerned with the final disposition of the waste mercury and 

associated future liabilities if mercury leaches out or otherwise enters into the 

environment 

o At recent limited test of ACI at cement plant, did not remove mercury. May have 

been due to high temperature. Must be concerned about acid dew point if 

lowering temperature to improve efficiency because of stack corrosion unless 

stack designed for acid gas condensation 

• SCR 

o At waste incinerator plant in Germany, SCR completely absorbed and oxidized 

elemental mercury with desorption after the SCR 

• Wet Scrubber 

o Removal of HCl may increase chlorine content of scrubber sludge beyond the 

0.1%, which would make the sludge unsuitable for use as gypsum 

o Looking for solutions that do not involve use of water because of potential 

detrimental effects on gypsum, issues of water scarcity, and final sludge disposal 

issues. 

II. Al Linero, Florida Department of Environmental Protection, gave a presentation outlining 

the issues associated with sources of mercury and possible control options, the 
October 30, 2009 

distribution of mercury in raw materials, and the use of fly ash from power plants 

from the Florida perspective. His presentation is available at: 

http://www.dep.state.fl.us/Air/permitting/construction/cement/Cement.ppt

III. Keith Barnett, U.S. EPA provided an overview of: 

• Possible EPA plans for the regulation of CO2 from cement manufacturing 

• Affects of CAA section 129 rules on cement kilns that burn solid waste