With the federal rules back under review, coal-fired utilities have received something valuable in their Effluent Limitations Guidelines compliance (ELG compliance) plan: time. The question is how to use it, especially regarding treatment options for the wastewater streams impacted by the pending rule. Here are some ideas.
For utilities that have been waiting for the rule’s (new) final version before acting — Playing the waiting game may no longer be in your best interest. All coal-fired plants will eventually be required to treat wastewater for the chemicals of concern (CoC) identified by the final ELGs. So why not use this time to take preventive measures that will improve water balance and plant operations now?
You might begin by ramping up your sampling efforts. A protocol for monthly, quarterly or continuous sampling can help paint a clear picture of your CoC content across a broad range of operational conditions. It will deliver the data you need to identify optimal treatment methods, saving you time and money in the long term.
This extra window of time can also be used to initiate a pilot treatment program. A variety of new treatment technologies are coming to market, including new membrane treatment and zero liquid discharge processes. These developers are eager to partner with utilities to prove the new technologies on the market.
For utilities that have already started planning ELG compliance — There are many ways for you to make productive use of the extra time from this delay. For example, take a fresh look at your operations to identify opportunities to reduce CoC production and limit the amount of treatment needed. This may mean asking pointed questions about your wet scrubber operations:
- Are we cycling up chlorides to the extent possible to reduce the volume of wastewater requiring treatment?
- Are we maximizing the reuse/recycling of water on-site to further reduce the wastewater load?
- Are we purging from the right spots — especially for solids — to minimize solids loading on wastewater treatment equipment?
For coal-fired plants that already installed a physical/chemical treatment system — Now is time for fine-tuning. Optimizing your treatment processes could save both time and money. Some questions to ask:
- How close/far is the effluent quality from the proposed limits for CoCs?
- Are we using the correct doses of the best chemical combination?
- What options should we consider for further treatment?
- Will any additional polishing be required?
The point is this: You’ve been given the gift of time. Don’t waste it.