Developing a Vacuum Distillation – Acid Absorption System for Recovery of Ammonia from Dairy ManureEPA Grant Number: SU835723
Title: Developing a Vacuum Distillation – Acid Absorption System for Recovery of Ammonia from Dairy Manure
Investigators: Tao, Wendong , Abrams, Neal
Institution: SUNY College of Environmental Science and Forestry
EPA Project Officer: Hahn, Intaek
Project Period: August 15, 2014 through August 14, 2015
Project Amount: $15,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2014) RFA Text | Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Materials & Chemicals , P3 Challenge Area - Water , P3 Awards , Sustainability
Dairy manure has high ammonia concentrations and contributes to air and water pollution. Dairy farms need cost-effective methods to upgrade their nutrient management plans. Our goal is to develop an innovative technology coupling vacuum distillation and acid absorption for sustainable recovery of ammonia from both anaerobically digested and undigested dairy manure. Ammonia in dairy manure can be distilled under a low vacuum at a temperature below the normal boiling point of water and absorbed in a sulfuric acid solution to produce ammonium sulfate as a value-added product. The specific objectives are to 1) evaluate the effects of temperature, vacuum, and dissolved solids concentration on ammonia recovery; 2) design an ammonia distillation – acid absorption system to produce ammonium sulfate granules with dairy manure; 3) construct a pilot-scale vacuum distillation – acid absorption system and develop operational parameters; and 4) perform a farm-scale economic analysis of the developed technology across its life cycle.
A laboratory vacuum distillation – acid absorption assembly will be used to evaluate the efficiency and energy consumption of ammonia distillation under different combinations of temperature and vacuum with filtrate of digested and undigested dairy manure that have different concentrations of dissolved solids. A pilot-scale ammonia recovery system will be operated by batch modes to investigate the kinetics of ammonia distillation and determine operational parameters, including feed depth and cycle length. Economic life-cycle analysis will be performed, taking a large-size dairy farm as an example, to assess sustainability of the proposed technology. Three graduate students will develop knowledge and skills on sustainable design for wastewater treatment and resource recovery. High school students in a Boy Scouts Engineering Camp and undergraduate students will gain hands-on skills with the pilot-scale system.
This project will develop a green technology to produce ammonium sulfate with dairy manure. It generates revenues while meeting regulatory requirements for farm nutrient management. By coupling ammonia recovery with anaerobic digestion and biogas-fueled electricity generation, heat is recycled, inhibition of ammonia to anaerobic digestion prevented, and greenhouse gas emission reduced. The pilot system will include a vacuum vessel for ammonia vaporization at boiling points lowered by vacuum, an ammonia absorption column to produce ammonium sulfate granules, and a vacuum pump to bridge the vacuum vessel and absorption column. Costs and benefits across its life cycle will be assessed.