Lambert Engineers, Inc.

Lambert Engineers, Inc. (LEI) has over eleven years experience in the field of air pollution control as it relates to the power industry. Experience has included component designs for particulate, NOx, CO, CO2 and SOx removal systems for coal and gas fired power plants. Two gas fired projects which we provided engineering support were selected as "Power Plant of the Year" by Power magazine.

Our knowledge base and design and field experience related to stiffened plate design at elevated temperatures is extensive. Many of our designers have over 20 years of experience in the design of casings and shells for ESPs, FGDs and SCRs in addition to miles of associated ductwork and associated supporting structures. Experience ranges from concept through construction of new systems, retrofits and upgrades.

Working closely with EPRI, Alstom Power is responsible for the design, construction and operation of the $10 million pilot plant, which engineers hope will be able to extract 90% of the CO₂ from 1% of the flue gas produced by of the plant's two 617MW coal-fired units. The goal of the project is to capture about 15,000 tons of CO₂ per year.

Lambert Engineers provided engineering project management, process engineering, structural engineering, electrical engineering, instrumentation engineering, and mechanical engineering services.

"The first step is to cool and clean the flue gas, which typically is at 120F to 140F, is water-saturated, and contains residual amounts of SO₂, NO_X, HCL, and particulate matter. Both steps can be accomplished by injected refrigerated water directly into the gas stream. As the gas is cooled, much of its water content condenses out, carrying the residual contaminants with it. The water is then evaporated in cooling towers, substantially reducing the total flue gas volume. The cooled flue gas leaves as a chilly (35F) and dry (<1% moisture) gaseous substance.

"The second process step is CO₂ absorption, which is similar to the SO₂ absorption common at many coal-fired plants today. After the 35F flue gas enters the bottom of the absorber vessel, it is forced upward against the current of a slurry containing a dissolved and suspended mix of lean ammonium carbonate (AC) and rich ammonium bicarbonate (ABC). Chemical reactions remove over 90% of the CO₂ in the flue gas, leaving it only with nitrogen, excess oxygen, and low concentrations of CO₂. Any residual ammonia is captured by a cold-water wash and returned to the absorber.

"The third step of the process takes the CO₂-rich slurry at 1,200 to 1,500 psi (anticipated for commercial use or for transportation to an enhanced oil recovery process or sequestration) from the ABC-rich output of the high-pressure pump and directs it to a heat exchanger. The heat exchanger dissolves the slurry into a clear solution at about 175F and sends it on to the high-pressure regenerator, where additional heat is added by a reboiler to strip away the CO₂ gas. The only by-product of the entire process is a small amount of water; it can either be treated by the plant's wastewater system or recycled and reused."¹

¹ Peltier, Dr. Robert. "Alstom's chilled ammonia CO₂-capture process advances toward commercialization." Power Feb. 2008: 38-41.

Lambert Engineers, Inc. supplied engineering and design services associated with the hot to cold conversion of three (3) electrostatic precipitators (ESPs) for each of the three 144 MW unit retrofits at Alcoa Warrick Station.

The conversion consisted of rerouting the existing gas flow to exit the economizer and pass through the air preheater before being routed to the new ESP inlet plenum.  The ESP outlet nozzle was modified for the new duct arrangement and the outlet duct was designed to tie-in to the new scrubber inlet duct.

Services included engineering and design for the structural ductwork for the new ESP inlets and outlets, support steel, turning vanes, fabricatior monitoring, and field services. LEI also provided a conceptual development strategy that resulted in an estimated direct $1 million savings to the customer versus an originally proposed competing concept in material and erection costs alone.