Digitalization – Cogeneration Power Plant -

Introduction

Digitalization, Artificial intelligence or machine leaning are buzzing word across several industries. Power of data has been realized in rcent times with the development in the data collection and analyzing facilities. Now industries are waiting for another change after industrialization period. Smart industry shall be the new norm for industries. Output of the industries are going to be improved like never before.

As digitalization is in the door step of industrial manufacturing industries. Cogen Boilers may be considered as first and foremost beneficiaries of digitalization for many process industries.

Cogen boilers or simply process boilers are the top energy consuming equipment’s for many process industries. With increase in the energy cost, efficiency improvement challenges and ease in benefit establishment. Cogens are best choice for Digitalization.

How we put Digitalization separate than automation

During last 20 years cogen power plant industries has been shifted from manual operation to auto operation. DCS or PLCs are in use to make power plant more safe, efficient and reliable. Almost all power plants are being operated though automation. Level of automation may differ from power-plant to power-plant based on companies’ requirement.

Now as we are already operating our power plant with good automation. We are quite comfortable with this operation and if someone says lets move towards digitalization. first question comes in our mind that what shall be benefit with the digitalization and whether we need to move ahead with digitalization.

So before explaining it further lets check the benefit we are already achieving through automation. Considering a coal fired boiler, Combustion air is controlled by sensing oxygen in flue gases and regulating FD fans, ID fans are controlled for maintaining required pressure in the furnace, Dearator level and steam are controlled though automation, Boiler drum level are contolled with feed pump, coal input is controlled by steam pressure or furnace temperature, list goes on and on. With putting these automation our system efficiency and reliability has improved and there is no doubt on this.

Need of Digitalization in Cogeneration power plant

Now let us check the efficiency and reliability of boiler, do our boilers are really efficient? Check for the last indirect efficiency test conducted in the boiler. Co-relate it with the direct efficiency we are generating with the coal procurement.

For most of the boilers the difference between indirect and direct efficiencies are 5-10%. If you ask why there is gap between direct and indirect efficiency. Most expert say indirect efficiency are checked on controlled environment while direct is the actual efficiency Considering process variation like loading, coal supply, fuel adjustments, process variation losses and other unaccounted losses so it shall be always lower. To the larger extent it is true but it cannot justify huge gap in the both efficiency and eliminate potential of saving on boiler efficiency.

Direct efficiency is the efficiency on which management is paying money and if we say our indirect efficiency is high what does it mean, Do it have some value in financial world? Sadly answer is No. But offcouse technical team has lots to say on indirect efficiency and its usage for allocating and eliminating losses in various area.

The reason for efficiency gap can be due to system loading, fuel quality, atmospheric changes, LOI change in Ash, Fuel feeding, change in process parameters and system adoptability to change with various parameter, etc. to address these problems we need to analyse all parameter and find relation with each other parameter and try to reduce variation for our maximum benefit.

Let us check one example for better understanding, During one of the case study with coal fired boiler, efficiency of boiler started dropping and operation team were struggling to put back boiler on the earlier efficiency. After analyzing all parameters team was unable to identify exact reason for efficiency loss. Almost all parameters were within operating limits.

Team invited expert for analysing the problem and it revealed that carbon monoxide ‘CO’ generation in the boiler has increased, Also as CO and oxyen level both were present in the flue gas it was hard to guess CO generation with just checking O2 level in the boiler. The reason of higher CO level was due to inefficient distribution of combustion air in the furnace. When incomplete combustion has increased and started creating combustion problem then only problem was identified. it took more than 15 days of inefficient operation for problem identification and another few days for rectification. We know only with one parameter establishing the problem is difficult we need to co-relate problem with other process variables.

Also it may be noted that manual analysis requires expertise in finding correct reason and further chances of error will vary with the level of experts. Further after analysis if action is taken it will be just like mitigating losses which has already been happening for many days.

This problem can be completely eliminated by machine learning in place with digitalization of boiler

For quality analysis we need to digitized complete power plant and build a system for machine learning to identify significant variables and its relation with other variables. With right analysis of variables right operational control can be planned.

Digitalization, artificial intelligence can be developed for analyzing the problem / gap in the process and establishing best solution in real time. With continuous data feed machine leaning can be made more robust and we can make best operational strategy for cogen boilers to prevent failure and losses which are otherwise difficult to estimate.

Conclusion

Artificial intelligence or digitalization is the next big opportunity available. People who grab this opportunity early shall be market leaders.Like various manual plants/ factories has now become obsolete, In future smart factories will rule the world and the factories who are not adopting change now may become history in future.

Cogenation is one of the most suitable area for artificial intelligence and it must be explored for getting maximum benefit.