Biological vs. Chemical Wastewater Treatment Which Is Better for Your Industrial Facility?
When comparing biological and chemical wastewater treatment strategies, how do you know which technologies will best suit your facility’s treatment needs?
Fundamentally, biological treatment uses living bacteria to do the bulk of the purification while chemical treatment uses chemical reactants to accomplish the work, and at first glance, the comparisons seem straightforward—but what contaminants do each of these processes remove? How do they compare in cost, footprint, energy use, and operation? Should your facility be using just one of these processes? Or should it be using both?
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Which pollutants do biological and chemical wastewater treatment systems remove?
When it comes to understating which technologies might make up your wastewater treatment system, one important factor in making that decision will come down to the type of contaminants that need to be removed. These are some of the ways biological and chemical treatment can help.
Biological treatment systems
Biological wastewater treatment systems are best at removing things that are easily biodegradable. For example, things used in your garden or kitchen that are made up of carbohydrates, polysaccharides, starches, sugars, proteins and edible fats (like lipids or plant-based oils). To this list, we can also add hydrocarbons (like ethane, hexane, pentane, octane, and nonane), as well as smaller aromatic compounds (like benzene, toluene, xylene, and simple phenols) which are also simple compounds that are easy for bacteria to break down and digest.
Chemical treatment systems
Pollutants removed with chemistry are typically toxic soluble metals (like aluminum, cobalt, copper, iron, mercury, nickel, lead, and zinc). Bacteria aren’t effective at removing these contaminants, but treating these metals chemically by adding either calcium hydroxide or sodium hydroxide helps form insoluble metal hydroxides that can precipitate out of the water solution.
Industries like mining and steel-making or oil and gas—wherever a facility is using raw materials from the earth that, as a byproduct, have a wastewater bearing these kinds of compounds—will generally use chemical rather than biological wastewater treatment technologies.