Which nutrients would you expect from a Pulp and Paper manufacturer?

• A. Nitrogen and Potassium
• B. Phosphorus and Sulfate
• C. Carbon and Nitrogen
• D. Nitrogen and Phosphorous

Answer: (D)

The key idea is identifying the nutrients most relevant to plant growth and to water quality from industrial waste. Pulp and paper mills typically release nitrogen in forms like ammonia and nitrates, plus phosphorus as phosphates, due to processing chemicals and cleaning agents. These two elements are the primary nutrients that drive microbial and algal growth in receiving waters, so they’re the ones you’d expect to find in the mill’s effluent. Potassium is also a plant nutrient, but it isn’t a defining or characteristic nutrient associated with pulp and paper effluent in this context. Carbon is a major part of organic matter rather than a limiting plant nutrient in this sense, and sulfate is more a pollutant/part of the processing chemistry than a primary plant nutrient. So nitrogen and phosphorus best fit the expected nutrient profile.