Reichhold Chemical Corp. Achieves Zero Oil Discharge and Improved Drain Water Quality 

Worldwide, Reichhold Chemical Corp. (now merged with Polynt Group) produces some 5600 products. At St. Helens, Ore., however, they produce only three: urea, ammonium nitrate, and ammonia. Plant drain water is discharged into the Columbia River, and although oily residues are minuscule because of a concerted program to keep oil off the floors, some is still present—drippage from ammonia compressors, vehicles, and machine maintenance chores.

The Problem

Although the amount of oil in drain and stormwater is not high, both plant and regulatory officials want as close to zero discharge of oils as possible. It can be a challenge to make effective oil removal happen in situations like these, where oil is only in minute concentrations, but still poses serious consequences if leaks occur.

The Solution and Measurable Results

All plant drainage, washdown and storm waters are channeled through floor and street drains into a two-compartment API settling chamber. This chamber is also used for collecting other oils–like crankcase oils–at the plant.

To tackle this, the plant installed several Model 8 Oil Grabber Oil Skimmers from Abanaki. Oily water first dwells in the sump, allowing oil to naturally rise to the surface of the water. The differences in surface tension and specific gravity between oil and water allow for periodic skimming. As the skimmer’s belt travels through the water in this sump, it collects oil and carries it back to a set of wiper blades that scrape oil off both sides. Recovered oil is then transferred to a holding tank.

Consistent Oil Removal Supports a Cleaner Process and Long-Term Environmental Compliance

A second skimmer is mounted in a sump that drains only from the urea plant. Here, process water is cleansed of oil by the skimmer and reclaimed in a steam stripping concentrator for reuse. Again, the volume of drippage oil that gets onto floors is small; during heavy rains, runoff into this sump can be diverted to the API channel for further treatment. With an 8” wide stainless-steel belt, the Model 8 removes oil at a rate of 32 gph, and requires little maintenance time compared with the alternative of constructing plant-made hose or belt skimmers.

Oil Removal Helps Keep Reichhold in Good Standing

Oil skimmers fit the bill for plants like this one, where the amount of oil being dealt with is small, but the ramifications are still big. Only a few gallons are collected every two months from this source—but zero oily discharge makes Reichhold a good neighbor to their environmentally conscious neighborhood.