How have chemical engineers advanced wastewater management? #WorldWaterDay
It’s World Water Day and to celebrate Chris Short, Chair of our Water Special Interest Group has given his thoughts on this year’s theme – ‘Wastewater’. We have members working all over the world in this area, as well as researchers looking at new and innovative ways to treat wastewater to help benefit society.
Check out Chris’ thoughts below, and don’t forget to comment with your own views on the subject.
Name: Chris Short
Job: Consultant and Chartered Chemical Engineer
Company: Chris Short Water Quality (previously Yorkshire Water)
Special Interest Group: Water, Chair
I’m not going to claim that chemical engineers were behind all the advances in wastewater management in the past century, greatly improving public health and the environment within industrialised countries.
However, chemical engineers have been increasingly involved in wastewater treatment over the last 100 years.
Whether applied to industrial processes, human, or animal wastes, their skills are ideally suited to add value in this area.
Throughout the years we’ve seen…
- Chemical engineering knowledge of unit operations transferred from other applications into wastewater treatment, especially in solid-liquid seperation.
- Development of models to describe and predict how things work, particularly in the activated sludge process
- Implementation of monitoring and control systems to minimise costs while maintaining output quality
- Researching and implementing solutions to new output quality challenges, such as heavy metal and nutrient removal
So how else do we contribute?
One way is manufacturing the chemicals and designing the equipment used to treat wastewater to high output standards. This includes coagulants, floc destabilisation aids, aerators, centrifuges, UV reactors, ion exchange systems, and increasingly, membranes.
Chemical engineers also draw on their training to seek to minimise waste streams. The rising cost, and in many areas the scarcity, of water drives the need deeper and wider into industries, including mining.
Wastewater is recycled and reused in many different ways, and sometimes the industrial production process is re-engineered to make products with less water, consequentially producing less wastewater.
Our profession has had to react quickly to an upward trend in energy prices, making engineering challenges much more difficult to tackle.
In the past, more energy-intensive processes were implemented to oxidise or separate polluting constituents, in order to meet tight output quality requirements and minimise the use of valuable land. Now we must be much more vigilant – a difficult circle to square – the solution being, for the most part, to offset the cost by releasing energy from the organic content of wastewater.
This has developed in recent years into a more general re-thinking of the ‘waste’ in ‘wastewater’.
Wastewater is a resource, containing not only water and organics, but also increasingly valuable nutrients. Phosphate is now being recovered and economics will, in time, favour the recovery – rather than destruction or dumping – of other constituents typically present in very low concentrations. That makes demands on chemical engineers that they, and the environment, thrive on.
Beyond the industrialised areas of the world, communities need basic sanitation as a cornerstone of improved health and life chances.
Chemical engineers are helping to develop and assess new techniques for practical application in these circumstances. These include appropriate developments in renewable energy and energy storage that can be applied to individual families or small community wastewater streams.
And of course, chemical engineers, including those active in Water SIG, are involved in educating and hopefully inspiring new generations of students to apply themselves to the future challenges of wastewater.
Thanks for joining me on this important day and do let me know of good examples you have thought of where chemical engineering has advanced wastewater management.
Water SIG Event – 20 April
Join the Water Special Interest Group on 20 April for a webinar on the Managua wastewater treatment plant in Nicaragua. It will exemplify at least two developments in treating the wastewater – the ecological benefit to Lake Managua, and the world’s largest solar sludge-drying plant.
If you would like to write a blog article for IChemE’s ChemEng blog, get in touch.