Grantee Research Project Results
Final Report: Treatment and Recycle of Olive Mill Waste at Rural Olive Mills in the West Bank
EPA Grant Number: SU835308Title: Treatment and Recycle of Olive Mill Waste at Rural Olive Mills in the West Bank
Investigators: Hong, Andy , Elmadhoun, A. , Lin, Ching-Chieh , Earl, Jessica , Conroy-Ben, Otakuye
Institution: University of Utah
EPA Project Officer: Hahn, Intaek
Phase: I
Project Period: August 15, 2012 through August 14, 2013
Project Amount: $15,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2012) RFA Text | Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Safe and Sustainable Water Resources , P3 Awards , Sustainable and Healthy Communities
Objective:
The Problem. Olive mill waste (OMW), solid and liquid byproducts of olive oil production, is a major environmental pollutant due to its high organic load, pH, and concentration of phytotoxic compounds which resist biological degradation if disposed of untreated. In its raw form, OMW contains high levels of conventional pollutants and several priority pollutants as defined by the US EPA Clean Water Act. The problem is particularly severe in the West Bank, where OMW is disposed of without treatment into waterways and cesspools, generating odor, surface water and groundwater pollution and inhibiting aquatic plants and animals. Due to high concentrations of pollutants in OMW, current treatment methods require advanced reactors, chemical additives, and/or large amounts of dilution water to reduce pollutant levels to meet discharge standards. However, these methods cannot be applied in the West Bank due to limited resource availability and lack of a centralized infrastructure for large-scale treatment.
Objectives. The objective of this project is to address the challenge problem by providing relatively simple processes and designs that can be installed for an affordable cost to olive mill owners to treat solid and liquid wastes generated from olive oil production, thus moving toward the goal of pollution prevention and sustainable agricultural practice. The project addresses people in the form of preserving fresh-water resources, the planet in the form of reducing surface- and ground-water pollution, prosperity in the form of direct and indirect reduction of societal economic burdens through utilization of process outputs for agricultural use and reduction in the cost and use of delivered freshwater.
Phase I Project Description. The project examined in the laboratory the feasibility of providing complete treatment to the olive mill waste. A complete OMW was obtained from a California mill. The waste was separated by sand filtration into the liquid and solid waste parts as necessary, though a typical 2-phase olive oil extraction process generates largely a pomace waste devoid of free liquid and a 3-phase extraction process generates both a solid waste and a liquid stream. The solid waste was amended with lumber saw dust (carbon source) and baking soda (sodium bicarbonate with acid-neutralizing capacity) and composted for 40 days into a product suitable as a soil additive. The compost product was incorporated into commercial potting soil and the mixture tested for its ability to sustain plants, which even incorporated at 25% it supported plant growth during the 2-month trial without noticeable sign of stress on the plants. The liquid waste diluted to the typical organic content of municipal wastewater was subjected to biological treatment through trickling filter for removal of organic constituents. The removal of organics was accomplished, reaching typical the quality of treated wastewater effluent within a few days. Laboratory analyses were used to define the quality and transformation/removal of waste into innocuous products. Both the compost technique and trickling filter treatment are widely practiced for food wastes and municipal wastewater, respectively, and are well acknowledged in environmental engineering disciplines as proven and economical means of treatment.
Summary/Accomplishments (Outputs/Outcomes):
We have documented our research and results in a manuscript submitted to Advances in Environmental Research – An International Journal for review and publication. A summary of findings is as follows:
- To a pomace waste sample from a California mill, we amended with saw dust (wood as a carbon source) and baking soda (NaHCO3 for its alkalinity) at weight ratios of waste/wood/NaHCO3at 70:27:1 and composted it for periods of 10 and 40 days; the compost was used as an additive to potting soil for transplanting. The results showed the compost-amended potting soil supported plant growth without noticeable stress over 60 days
- The olive mill pomace amended with saw dust pellets and baking soda was converted in 6 weeks to a soil additive, capable of supporting plant growth even incorporated at a high concentration of 25% in the potting soil.
- The pomace sample was also blended into slurry and introduced to a water-circulating pond installed with a tricking filter (P/TF) to examine any inhibitive effect of the pomace on biological removal of organic waste. The P/TF system removed BOD and COD by >90% from the waste liquid within 2 days, with a first-order rate constant of 1.9 d-1 in the pond.
- The holistic ground mill waste was treated as a slurry in a circulating pond/TF system with no apparent inhibitive effects on organic removal, but with a rapid first-order degradation rate constant of 1.9 d-1, suggesting strong treatment feasibility.
Conclusions:
The treatment of mill waste stream can be carried out at rural sites by separation of the liquid from the solid; the solid is to be composted and the liquid to be treated by a circulating pond and trickling filter system. The low-cost, effective compost and trickling filter techniques have been found successful in achieving the Phase I project objectives of OMW treatment through demonstration in the laboratory. Based on Phase I results, a preliminary onsite treatment design is made:
Journal Articles on this Report : 1 Displayed | Download in RIS Format
Other project views: | All 2 publications | 1 publications in selected types | All 1 journal articles |
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Type | Citation | ||
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Li X, Lin C-C, Sweeney D, Earl J, Hong A. Composting and trickling filter for treatment of olive mill waste. Advances in Environmental Research 2013;2(2):131-141. |
SU835308 (Final) |
Exit Exit |
Supplemental Keywords:
Treatment technologies, environmental education, water conservation, waste to value, agricultural wastes, wastewater treatment, sustainable practiceRelevant Websites:
EPA OliveWastes Exit
Environment - International Olive Council Exit
Your Olive Branch.org Exit
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.