OCR Text |
Show Cost The cost of Thermal DeNOx varies considerably with the specific application and degree of system sophistication required. For utility application, elaborate controls, emission monitoring, and redundancy are required. For steam generators a much simpler system is consistent with the design and operation of the controlled unit. Refinery applications are anticipated to be an intermediate circumstance. Another important factor is whether hydrogen is required. Hydrogen usage complicates the control and safety requirements. Estimated Thermal DeNOx costs for non-hydrogen systems including ERE royalty and capital charged at 20% per year are $0.06 to $0.09 per million BTU fired. The capital investment is estimated to be $9 to $17 per kw equivalent (installed). For hydrogen utilization, the high end of the range could be increased by about 20%. The low end of this range is an estimated cost for a group of six 50 million BTU/hr units (rated steam output) with common ammonia tankage, common evaporator facility, and manual controls. The estimated capital cost of about $320,000, including ERE license fees, was amortized at 20% per year with 300 days/yr operating at 80% load. On this basis, estimated annualized cost was $0,056 per million BTU fired with a capital cost of $8.53 per equivalent kw. Assuming 50% NOx reduction from 0.37 lbs NOx per million BTU, the cost effectiveness would be $0.30/lb of NOx reduction of $600/ton. The high end of the range is based on an estimated cost for a 230 MW utility boiler application with extra capacity, redundant critical components and a sophisticated automatic control system. The estimated project cost is abour $4,000,000 with the same annualization as above. On this basis, estimated annualized cost was $0,088 per million BTU fired. Assuming 40% reduction from about 0.3 lbs NOx per million BTU, the cost effectiveness would be $0.75/lb or $1500/ton. The costs presented are rough estimates based on engineering judgment and assumptions as necessary. They were not obtained from Exxon. 4-20 P-233 |