I believe SD surely has something to offer to our Environment. Taking hazardous waste as an example, with systems dynamics we consider the inflows and outflows of the waste (inflow=how much we are mgenerating, outflow=how much we are degrading). Under inflows we will need to know the rate of waste generation, the type, the industries doing so etc. and under outflow we need to know the degradation rate if any, the sustainable disposal methods etc. These factors are also interlinked with other factors eg municipal waste collection and disposal, hazardous waste handling, industrial waste generation, demand which also interact with many other systems forming a complex systems. so with all the information we can be able to predict the waste generation in say 10 years and the idea is to play around with the inflows so as to reduce the outflows. and maintain a clean and safe environment =sustainability.

Thank you Jefline for your contribution. Would you please add some references to support your statement.

Dear Professor Sadeghi,

Thank you for your recommendation. I am thinking to apply SD together with a HAZID method to the offshore decommissioning. I thought before jumping stop and stare.

Dear Professor Yasseri,

You are most welcome. I found your question very interesting I believe you are going to open a new window to apply dynamic systems to protect the offshore environment. Based on the existing knowledge, improvements in environmental performance do not occur abruptly. Success requires a permanent commitment to environmental leadership, including but not limited to the following elements:

- an overall philosophy and corporate culture established and demonstrated by senior management;

- acceptance of and commitment to the overall philosophy, governing principles, and policies by all employees;

- clear standards of performance and operating procedures; technologies and technical resources qualified to meet challenges in a competitively advantageous manner;

- well-educated and well-trained staff at all levels; and systems to measure and evaluate current performance, identify areas for continuous improvement, and incorporate these into new performance standards and goals.

Improving environmental performance requires successful implementation of all of the above-described leadership elements. However, a system to measure and evaluate environmental performance is certainly a key element and one that companies have been struggling with over the past several years. Overall, a dynamic system should be applied to improve the existing systems.

I wish you the best of luck in implementation of dynamic systems in offshore field to protect the environment.

Dear Professor Sadeghi

Thank you for sharing your wisdom. I must try and remember them. I should make a pair from earring of them and wear them, so that the reverberation of your words is always in my ear.

Thanks

Dear professor Yasseri,

Yes indeed, system dynamics methodology is very useful to understanding and analysing the interactions between various components over time as well as providing feedback of each part of the system as it is the case for waste management.

I used this method for analysis of environmental sustainability of supply chain.

I hope some of my previous publications be useful as examples of application of system dynamics. Please consider the following references:

Golroudbary, S. R., El Wali, M., & Kraslawski, A. (2019). Environmental sustainability of phosphorus recycling from wastewater, manure and solid wastes. Science of The Total Environment, 672, 515-524.

Golroudbary, S. R., & Zahraee, S. M. (2015). System dynamics model for optimizing the recycling and collection of waste material in a closed-loop supply chain. Simulation Modelling Practice and Theory, 53, 88-102.

Golroudbary, S. R., Calisaya-Azpilcueta, D., & Kraslawski, A. (2019). The Life Cycle of Energy Consumption and Greenhouse Gas Emissions from Critical Minerals Recycling: Case of Lithium-ion Batteries. Procedia CIRP, 80, 316-321.

El Wali, M., Golroudbary, S. R., & Kraslawski, A. (2018). Impact of recycling improvement on the life cycle of phosphorus. Chinese Journal of Chemical Engineering.

Rahimpour Golroudbary, S., Krekhovetckii, N., El Wali, M., & Kraslawski, A. (2019). Environmental Sustainability of Niobium Recycling: The Case of the Automotive Industry. Recycling, 4(1), 5.

Dear Saeeed,

Thank you for the list of references. Would you please what software you used for the simulation?

Regards

Sirous

Dear professor Yasseri,

For those mentioned publications, I used Vensim ( https://www.vensim.com) and Anylogic ( https://www.anylogic.com).

System dynamics analysis starts with material and energy balance. Need to know about energy content associated with Haz. wastes. Total energy inflow and energy extracted. then development of degradation system.

Dear Mr Thirumalesh

Thank you for taking time and answering my question.

Nice summary dear Dr. Saeed Rahimpour Golroudbary " I agree this answer "the system dynamics methodology is very useful to understanding and analyzing the interactions between various components over time as well as providing feedback of each part of the system as it is the case for waste management.

I used this method for analysis of environmental sustainability of supply chain".

Dear Professor Al-Khashman,

Thank you for your comment. How do you react to this statement:

" a lot opinion are injected into the model with little fact to check them, except using the same opinion to see if the results are reasonable"

Dear Professor Yasseri,

You are most welcome and thank you so much for your kind message in response on my answer. I am very glad that you are satisfied from my answer.

Best regards

Thank you very much Dr. Sirous Yasseri for your nice comment.

Dear Kabir,

I value your opinion. I am always grateful to you and others who took time and wrote down what they think.

SY

Dear Sirous

Thank you for your kind message.

KS