Energy transition & emerging technologies in the boiler industry

Abhishek Bhave, Growth Unit Head, Thermaxglobal

An Experienced professional with a history of working in diverse functions from Engineering to Sales & Marketing in capital goods or industrial engineering industry and specialized in boilers, gas, petroleum.

The fuel source for steam & power has been continuously changing over the decades. This change is driven by availability, costs & environmental considerations. Decarbonization and sustainability have been the key drivers of energy transition and will continue to be so over next few decades. This will provide opportunities for new technologies and business models. The recent developments in promoting co-firing of biomass in power plants, focus on renewables and waste to energy have significantly influenced the developers and users. It is therefore paramount to offer a comprehensive adaptive solution in power plants and boiler industry to handle the energy transition. The main considerations for energy transition is the source of fuel, fuel cost, availability, environmental impact and process waste disposal.

The main considerations for equipment design are reliability, availability, efficiency & flexibility. The merging technologies will have to excel on these parameters & provide an economical solution to users, specially customized for their situations. Some of the solutions for non-recyclable solid waste or multi-waste fired waste to energy boilers like FlexiSource™ are important steps in that direction.

The industries in India especially those needing power have started efforts to de-carbonize their energy requirements. For every new power demand, the users are evaluating available renewable solutions. Industry is asking the original equipment manufacturers to develop multi-waste input energy systems to maximize renewables. Users are looking at multi-waste fuel options like biofuels, agriculture waste, non-recyclable solid waste, refuse derived fuel to have higher input flexibility at the same time maintaining economic viability. We have seen clients favouring available agriculture stock & biofuels around their plant areas for combusting it in the advanced boiler systems with integrated gas cleaning system. This agro-energy demand has given a push for newer technology that can accommodate multi-waste fuel options in single unit giving maximum flexibility.

The multi waste fired boilers like FlexiSource™ willhelp users to get required flexibility in sourcing energy inputs and boiler duties. The solution utilizes automated & digitally enabled combustion system and special feeding system ensures better controllability & efficient combustion of multi-waste fuel. These boilers are capable of combusting multiple waste fuels including varieties of biomass, agricultural waste or residues, sludge, non-recyclable solid waste, biofuels and refuse derived fuel in one go. The flue gas cleaning system (FGCS) are often installed at the tail end along with these boilers that can effectively remove harmful emissions to meethighest environmental standards.

Similarly, we have seen increased focus on utilizing non-recyclable solid waste or refuse derived fuel in Waste to Energy boilers to safely destruct the waste in an environmentally friendly way at the source. This not only helps the users to meet their steam or captive power requirements but also displaces conventional use of fossil fuels that would have been usedotherwise. The developers have understood that a successful plant will need an indigenized solution that can customize the best available technology to meet local requirements. The special solution of destructing non-recyclable Solid Waste (NRSW) for paper mills in an environmentally friendly way within the same premise where waste is generated is a testimony to energy transition & sustainability.

The solution is developed keeping in mind the fuel physical nature, composition, moisture variation, ash characteristics etc. The NRSW is a mixture of non-recyclable waste materials rejected from different process points in recycling paper plants. The mix contains high moisture of 45 – 50 percent and varying sizes of 1 mm to 400 mm, making it challenging to handle and combust in any conventional boiler. The flue gases generated contain traces of harmful emissions that are then treated in an integrated flue gas cleaning system. A leading paper mill implemented a full-scale project at their plant in Gujarat, India for safely destructing 33,000 Tons Per Day NRSW annually in a waste to energy boiler to generate around 14 Tons Per Hour steam at pressure of 45 kg/cm2(g) and temperature of 400 C. The steam generated will be used to generate captive power as well as for meeting plant utility requirement.

This solution has helped the customer to safely utilise and dispose non-recyclable solid waste in a year in an environment friendly way and reduce the overall carbon footprint. This solution not only saves challenges in managing this waste along with associated transportation costs to nearby kilns or incinerators or landfills but also frees up the land being utilized for waste storage with 9090 percent reduction in waste volume. This also helps the user to displace use of fossil fuels to generate steam. The steam to fuel ratio is further improved through enhanced combustion control systems, fuel preparation and feeding. The waste generated is consumed as fuel at the source thereby reducing the associated environmental impacts and making this a sustainable green solution. The integrated flue gas cleaning system is designed for treating the waste to energy boiler off gases to ensure the emissions at the stack are below the desired emission norms in the country. These gases are treated in gas condition tower and reaction duct followed by a bag filter meeting the highest environmental standards.