• L&T-Sargent & Lundy
  • L&T-Sargent & Lundy

Air Quality Control Systems (AQCS)

L&T-S&L and Sargent & Lundy (S&L) offer a wide range of Air Quality Control System (AQCS) Services to reduce PM, SOx, NOx and Hg emissions in coal-based power plants.

Over the past two decades, S&L has assisted numerous plant owners in the development of strategic compliance plans to address myriad regulations at federal and state levels. These strategic planning activities have led to an industry-leading role for S&L in the engineering, design, construction, and deployment of emission control technologies across the U.S. utility industry.

With this level of worldwide presence, S&L expertise & knowledge base is available to L&T-S&L in its endeavor to provide comprehensive and proven engineering services for the emerging needs of stringent environmental emission control norms.

The main technologies for AQCS are:-

    • Limestone-Based Wet FGD Systems
    • Seawater FGD Systems
    • Dry FGD Systems
    • Dry Sorbent Injection Systems
    (SCR & SNCR)
    • Selective Catalytic Reduction Systems
    • Selective Non-Catalytic Reduction Systems

Through comprehensive experience and technical acumen, L&T-S&L and S&L’s environmental experts can help Plant Owners to comply with Regulatory norms while minimizing the risk and capital expenditure. The wide range of customized services offered for AQCS Technologies can be summarized below:-

1. Conceptual Design and Technology Studies

The conceptual design phase is the most important phase of the project because the character of the implemented project will evolve directly from this effort. Hence, this phase will include exhaustive interactions with our clients and the plant personnel to ensure that project specific requirements are included in the overall design. Based on the information gathered, studies will be performed to determine the specific requirements of the retrofit project, and a conceptual layout will be prepared.

  • Design Basis : Identify the basic design basis to achieve the required emission reductions.
  • Technology Selection : Evaluate the technologies to determine which represents the best selection for each power plant based on its configuration, fuel properties, performance requirements, and other site-specific factors to minimize both capital and operating costs.
  • Preliminary General Arrangement : Prepare general arrangement drawings showing ductwork configurations, equipment locations, and preliminary footprint requirements based on the results of each of the studies.
  • ID Fan Draft Study : Review existing ID fan equipment margin to determine whether it is adequate to meet the lower operating pressures or potential transit pressure experience during retrofits. Based on the finding, suitable recommendation on additional structural reinforcement will be made.
  • Auxiliary Electrical Study : Review the existing auxiliary power system to determine if additional equipment is needed to support the additional loads added due to the retrofit project.

  • Utility Consumption Study : Evaluate all utilities required to support the processes, including makeup water, service water, instrument air, process air, steam, etc.
  • DCS Integration Study : Prepare an estimate of the additional I/O capacity for the new environmental equipment. This will be the basis to evaluate whether the plant’s existing Distributed Control System (DCS) can accommodate the additional control points, or whether new hardware will need to be included in the project.
  • Preliminary Project Schedule : Prepare a project schedule to illustrate the project duration and major tasks to be completed.
  • Reagent Selection Study : Evaluate cost issues, safety issues, and other issues in recommending a reagent for the SCR process. Depending on the FGD system type, L&T-S&L will evaluate the issues related to reagent selection. 
  • Makeup Water Treatment Study : Review the available sources of makeup water for suitability in each application.
  • Byproduct Disposal Study : Study the byproduct disposal requirements depending on the FGD system.
  • Economizer Bypass Study : Evaluate bypass systems in order to find the most cost-effective solution for the plant.
  • GGH vs. Wet Stack Study : Evaluate the most economical solution with respect to the stack to be used.
  • Economic Analysis and Cost Estimating : Compare capital and O&M costs to evaluate the lowest net present value of the available technology and equipment. After the technology is selected, more detailed cost estimates can be prepared to support project budgeting.

2. Procurement Support

Support shall be provided with the procurement of the required air quality control systems and auxiliary equipment. Our overall procurement support will include the following:-

  • Specification Preparation : Prepare equipment specifications for bid to supply the air quality control equipment required. Scope requirements, process performance, and emission reduction guarantees are specified for contractors to prepare competitive bid packages.
  • Bid Evaluation and Recommendation : Evaluate the proposals and produce a letter of recommendation to support the award of the air quality control equipment.
  • Technical Negotiations and Contract Conformance : A conformed specification shall be prepared for clarity on contract. Based upon the technical discussions, technical specification may be changed to capture all exceptions and clarifications that were determined to be acceptable. 

3. Project Implementation

Support shall be continued to be given even after the award of the environmental equipment contract. During this phase of the project, detailed engineering shall be required to integrate the environmental equipment into the existing plant systems. Document reviews shall also be done to ensure that the contractor is performing their work according to the agreed upon specification. Support shall be provided to help monitor key process deliverables from the environmental equipment suppliers.

Download Air Quality Control Systems (AQCS) Brochure