Introducing energy efficiency programmes drives down cost, reduces harmful emissions and improves production says
Abdelghani Henni.
Petrochemicals producers are struggling to reduce greenhouse gas emissions and production costs, and implementing major energy efficiency initiatives is delivering tangible results according to the industry’s leading technology providers.
Energy is a significant cost factor in downstream business. “The petrochemical industry is responsible for 70% of the chemical industry’s expenditures on fuels and 40% of the expenditures on electricity,” explains Shunsuke Takagi, planning group, Mitsubishi Heavy Industries.
“The costs of energy and raw materials make up roughly two thirds of the total value of shipments of the petrochemical industry. Because energy is such an important cost factor, energy efficiency is a very important opportunity for cost reductions,” he adds.
Throughout the production process, feedstocks are converted to olefins, polyolefins and other products at high temperatures, requiring huge energy consumption.
“A lot of the chemical conversions are exothermic but in many cases, the reaction heat can be recovered to be used elsewhere in the plant,” says Takagi. These separation steps consume electricity and heat. “Heat is either supplied by direct heating or by steam produced in stand-alone boilers or via cogeneration of electricity and heat,” he explains.
Efficiency Opportunities
A large variety of opportunities exist within the petrochemical industries to reduce energy consumption while maintaining or enhancing the productivity of the plant.
Studies by several companies in the petrochemical industries have demonstrated the existence of a substantial potential for energy efficiency improvement in almost all facilities.
“Improved energy efficiency may result in co-benefits that far outweigh the energy cost savings, and may lead to an absolute reduction in carbon dioxide and other fuel-related emissions,” says Takagi.
“Major areas for energy-efficiency improvement are utilities (30%), fired heaters (20%), process optimisation (15%), heat exchangers (15%), motor and motor applications (10%), and other areas (10%),” says Rexi Chacko, project manager at Toshiba.
“Of these areas, optimisation of utilities, heat exchangers and fired heaters offer the lowest investment opportunities for improving energy efficiency.
Experiences of various chemical companies have shown that most investments in the field of energy efficiency are relatively modest. However, all projects require operating costs as well as engineering resources to develop and implement any efficiency initiative.
“Every petrochemical plant will be different. Based on your unique situation the most favourable selection of energy-efficiency opportunities should be made,” says Shojiro Ishigaki, overseas business division at the Tokyo based Xenesys.
Energy use is the major source of emissions in the petrochemical industry, making energy-efficiency improvement an attractive opportunity to reduce emissions and operating costs.
“Energy efficiency should be an important component of a company’s environmental strategy. End-of-pipe solutions can be expensive and inefficient while energy efficiency can be an inexpensive opportunity to reduce pollutant emissions,” says Ishigaki.
GPIC Experience
In the Middle East, Bahrain’s Gulf Petrochemicals Industries Company (GPIC) has adopted a wide-ranging energy efficiency initiative at its complex and is the first petrochemical company in the Middle East to use a carbon dioxide (CO2) recovery plant, in order to recycle carbon emissions.
“The recovery unit can capture 450 metric tonnes of CO2 per day, one of the world’s largest capacity units for the chemical application,” says Abdulrahman Jawahery, GPIC general manager. “Captured CO2 will be used as feedstock for urea and methanol synthesis processes. The technology can recover approximately 90% of the CO2 in flue gas,” he explains.
Solutions
Introducing new process technologies and integrating utilities help producers to reduce the greenhouse gases emissions, whilst at the same time improving production.
“One of the major benefits we are capable of offering is setting up an integrated energy solution across industrial sites (including buildings, utilities, plants and power plants) which provide optimum solution levels in a single, holistic approach,” says Andy Coward, advanced solutions sales manager, Honeywell Process Solutions (HPS).
“An extensive energy management programme incorporating both software technology and focused hardware upgrades can be expected to yield benefits of between 10% and 25% reduction in energy consumption. For a refinery this can easily equate to millions of dollars per year,” Coward adds.
The cost of installation varies depending on the scale of the implementation. “A reasonable rule of thumb is that control and automation projects will typically have a payback period in the order of 9 months to a year for an investment of between US$200 000 and $1 million. Energy efficiency projects that require capital investment will typically have a somewhat longer payback period,” reveals Coward.
Toshiba offers other vehicle for payment. “If we save a particular company one million dollars per month, we would take a percentage of that saving as payment for our services,” says Chacko. Although technological changes in equipment conserve energy, changes in staff behavior and attitude can have a great impact.
“Staff should be trained in both skills and the company’s general approach to energy efficiency in their day-to-day practices. Personnel at all levels should be aware of energy use and objectives for energy efficiency improvement. Often this information is acquired by lower level managers but not passed to upper management or down to staff,” says Chacko.
“Though changes in staff behavior, such as switching off lights or improving operating guidelines often save only very small amounts of energy at one time, taken continuously over longer periods they can have a great effect,” he observes.
