Biosolids Recycling Research Articles

Environmental Comparison of Biosolids Management Systems Using Life Cycle Assessment

To fill a gap in the information available to nonmetropolitan policy makers, eight scenarios combining processing technologies and end-uses for biosolids products associated with a 40,000 equivalent-person town were modeled using environmental life cycle assessment (LCA). An uncertainty analysis examined several key assumptions. The results showed that the reuse of biosolids products can be environmentally beneficial but transportation distances can change the preferences between technologies, and drying biosolids using petrochemical methane rather than biogas (produced endogenously in the wastewater facility) significantly worsens environmental performance. System scale can also invert option preferences. This work demonstrates an application of LCA to a strategic engineering question. We also examine the methodological feasibility of considering carbon sequestration and water offsets beyond those typical of previous studies. As the development of scientific data regarding the benefits of biosolids recycling develops,there may be potentialto reward agricultural businesses that choose to reduce their environmental burdens using biosolids. A life cycle management approach to this will be necessary.

Fate of organohalogens in US wastewater treatment plants and estimated chemical releases to soils nationwide from biosolids recycling.

This study examined the occurrence in wastewater of 11 aromatic biocides, pesticides and degradates, and their fate during passage through US treatment plants, as well as the chemical mass contained in sewage sludge (biosolids) destined for land application. Analyte concentrations in wastewater influent, effluent and sludge from 25 facilities in 18 US states were determined by liquid chromatography electrospray (tandem) mass spectrometry. Dichlorocarbanilide, fipronil, triclocarban, and triclosan were found consistently in all sample types. Dichlorophene, hexachlorophene, and tetrachlorocarbanilide were detected infrequently only, and concentrations of the phenyl urea pesticides diflubenzuron, hexaflumuron, and linuron were below the limit of detection in all matrixes. Median concentrations (+/-95% confidence interval) of quantifiable compounds in influent ranged from 4.2 +/- 0.8 microg L(-1) for triclocarban to 0.03 +/- 0.01 microg L(-1) for fipronil. Median concentrations in effluent were highest for triclocarban and triclosan (0.23 +/- 0.08 and 0.07 +/- 0.04 microg L(-1), respectively). Median aqueous-phase removal efficiencies (+/-95% CI) of activated sludge treatment plants decreased in the order of: triclosan (96 +/- 2%) > triclocarban (87 +/- 7%) > dichlorocarbanilide (55 +/- 20%) > fipronil (18 +/- 22%). Median concentrations of organohalogens were typically higher in anaerobically than in aerobically digested sludges, and peaked at 27 600 +/- 9600 and 15 800 +/- 8200 microg kg(-1) for triclocarban and triclosan, respectively. Mass balances obtained for three primary pesticides in six activated sludge treatment plants employing anaerobic digestion suggested a decreasing overall persistence from fipronil (97 +/- 70%) to triclocarban (87 +/- 29%) to triclosan (28 +/- 30%). Nationwide release of the investigated organohalogens to agricultural land via municipal sludge recycling and into surface waters is estimated to total 258 000 +/- 110 00 kg year(-1) (mean +/- 95% confidence interval), with most of this mass derived from antimicrobial consumer products of daily use. This study addresses some of the data gaps identified by the National Research Council in its 2002 study on standards and practices of biosolids application on land.

下水汚泥の緑農地利用

下水汚泥の緑農地利用

Effect of Amendment Addition on Biosolids Odors based on Gas Chromatography Analysis and Odor Panel Observations

Many claims have been made regarding the effectiveness of chemical additives and amendments (A&As) to reduce the potential for odors from organic residuals. Various A&As have been added to biosolids during conditioning and dewatering, or directly to dewatered cake, with limited success. The Philadelphia Water Department (PWD) annually produces >200,000 wet tons of biosolids via anaerobic digestion, followed by high speed centrifuge dewatering. Nuisance odors were reported during staging/ storage of biosolids cake at the Philadelphia Biosolids Recycling Center, and land application sites. This manuscript summarizes results for several A&As that was evaluated relative to their potential to reduce odors in staged and/or stored PDW biosolids. Conventional head space sampling from incubated biosolids samples and GC-MS analysis was coupled with human sensory evaluation. Of the A&As selected for study, none were effective for both staging and storage odor mitigation situations. Lime kiln dust performed best for staging, and high carbon wood ash performed best for storage. Correlation of specific odorant gasses with odor panel results revealed mixed findings.

Biomass production of hybrid poplar ( Populus sp.) grown on deep-trenched municipal biosolids

Environmentally sustainable options for recycling municipal biosolids generated from wastewater treatment plants are needed. We measured the wood biomass production of a 50 ha hybrid poplar ( Populus spp.) tree farm where biosolids were applied at a rate of 380 metric tonnes per hectare in deep trench rows (46 cm deep, 107 cm wide, and 20 cm below the surface) of a clay spoil at a former sand and gravel mine located near Washington, DC. Our aim was to quantify how much wood biomass was produced within a 6-year rotation and to develop allometric models useful for easily estimating wood biomass for this type of novel plantation. We randomly sampled trees from stands 2 to 6 years old to measure total tree height, diameter at breast height (DBH), and total tree weight. The 6-year-old trees had a mean height of 9.7 m and a mean biomass of 20.5 kg. DBH was the best allometric predictor of biomass ( r 2 = 0.98, P < 0.001), especially for trees with diameters greater than 4 cm. Tree height was a significant, but less precise predictor of biomass ( r 2 = 0.87, P < 0.001). Standing wood biomass after 6 years was 22,100 kg/ha. Ecological recycling of municipal biosolids to tree plantations can be an environmentally sustainable and energy conscientious means for producing energy, while restoring degraded habitat.

The role of sludge conditioning and dewatering in the fate of nonylphenol in sludge-amended soils

One of the main concerns associated with the recycling of biosolids to arable land is their contamination by organic pollutants, like endocrine disruptors. Conditioning and dewatering are usually the last steps of the sewage sludge treatment, before its further utilization. The choice of the specific conditioning/dewatering method may have an effect, not only on the amount of residues in the biosolids, but also on the fate of these compounds in amended soils. Anaerobically digested wastewater sludge was conditioned at lab-scale by means of physical and chemical methods and subsequently dewatered by centrifugation. The produced biosolids plus non-conditioned and non-dewatered sludges were amended separately to soil and spiked with 14C radiolabelled single isomer of nonylphenol. The persistence and leaching potential of nonylphenol after an incubation period of three months were correlated to the sludge treatment method. In comparison to non-conditioned sludge, 54% and 72% higher amount of pollutant residues were extractable when freeze-thawed and limed sludge, respectively, were used. Conditioning of sludge with cationic polymer decreased the leaching potential of nonylphenol in sludge-amended soils, while liming increased it. Fractions of the model compound recovered as extractable and bound residues were analyzed in order to interpret nonylphenol fate.

Alternative Project Delivery: A Public–Private Partnership for California's First Design-Build Biosolids Recycling Facility

Alternative Project Delivery: A Public–Private Partnership for California's First Design-Build Biosolids Recycling Facility

Managing California's Ever Changing Biosolids Regulatory Climate through the State's First Design-Build Biosolids Recycling Facility

Managing California's Ever Changing Biosolids Regulatory Climate through the State's First Design-Build Biosolids Recycling Facility

Biosolids‐Amended Soils: Part II. Chemical Lability as a Measure of Contaminant Bioaccessability

Biosolids recycling by amending agricultural soils has increased significantly over the last few decades. The presence of contaminants in small, bioavailable quantities has generated concerns about health threats resulting from accumulation of potential toxins in the food chain. In this study, land application of biosolids was evaluated for environmental risk. Chemical lability tests for metals were used for the test soils and included analyses for water soluble, exchangeable, and metals extractable by the physiologically based extraction test. Chemical extractions detected slight increases in labile metal concentrations for many of the treated soils, particularly those receiving long-term applications of 5 years or more. Significantly higher metal concentrations were observed in the soils that had been exposed to biosolids before the U.S. Environmental Protection Agency (Washington, D.C.) 503 Rule (U.S. EPA, 2004) was implemented.

Biosolids recycling: Nitrogen management and soil ecology

Biosolids are municipal wastewater treatment solids that meet regulatory standards for land application. Most biosolids are a rich source of N, P, and micronutrients. Although the use of biosolids on food crops remains controversial in the public eye, decades of research have led to the development of regulations for the safe and beneficial use of biosolids in agriculture. Emerging areas of research include biosolids in commercial and home horticulture, the fate of pathogens and organics in biosolids, the use of biosolids in the remediation of contaminated sites, and biosolids effects on soil ecology. Nutrient management remains the most critical day-to-day issue for land application of biosolids. Recent research on plant-available nitrogen (PAN) in biosolids has found that N availability is similar over a range of biosolids processing types, and that growing-season climate is a key factor affecting available N. Regionally based predictions of PAN have been developed for the United States, and could be extended into Canada. Relatively little is known about the effects of biosolids applications on soil ecology, but soil nematodes offer an opportunity to evaluate the structure and function of the soil ecosystem following biosolids applications. We have studied responses of nematode communities to application of municipal biosolids and composts, in forage production systems and orchards. Both types of amendments increased the abundance of enrichment opportunists, for up to 3 yr after single applications. These data on the persistence of increased enrichment opportunists have provided insight into the longevity of amendment-induced enhancement of biological activity and nutrient cycling. Cumulative biosolids applications of 90 Mg ha-1 have caused reductions in abundance of pollutant-sensitive Dorylaimida. The extent to which this change is the result of metal or nutrient loading is unclear and deserves more detailed study. Key words: Biosolids, plant-available nitrogen, soil ecology, nematodes

Biosolids Recycling: An Assessment of Public Perception and Knowledge

Biosolids Recycling: An Assessment of Public Perception and Knowledge

Alternative Project Delivery California's First Design-Build-Own-Operate Biosolids Recycling Facility

Alternative Project Delivery California's First Design-Build-Own-Operate Biosolids Recycling Facility

Biosolids Program Reliability through California's First Design-Build Biosolids Recycling Facility

Biosolids Program Reliability through California's First Design-Build Biosolids Recycling Facility

Recycling biosolids to pasture-based animal production systems in Australia: a review of evidence on the control of potentially toxic metals and persistent organic compounds recycled to agricultural land

Biosolids from municipal waste water treatment are commonly used in agriculture as a source of nutrients, organic matter, and irrigation. There is, however, concern that the use of biosolids on pasture can lead to an accumulation of potentially toxic metals (PTM) and persistent organic compounds (POC) in the surface layers of soil and associated herbage that can be ingested by grazing livestock. This review examines the following two key questions. Is the use of these materials in an agricultural setting safe and practical? Is the use of biosolids safe in all climates, on all soils, and is it sustainable over the long term? To answer these important questions, the Australian regulatory framework is examined in light of similar legislation in Europe and the United States on the basis of scientific evidence that underpins the published limits, contaminant gradings, annual loadings, and prescribed restrictions on the use of biosolids in agriculture. The review concludes that the regulatory frameworks currently enacted at State level suffer from a lack of data to underpin the risk assessments conducted to prevent transfer of PTM and POC to the human food chain from livestock production and the basis of published thresholds is poorly defined. The important areas of future research are identified as studies on acquisition and transfer of PTM and POC to grazing animals and the subsequent effect of attenuation of the pollutant on the human food chain, the validation and acceptance of methods to quantify POC in biosolids, the effect of recycling of biosolids on the economic performance of pasture-based agriculture, and the market perception of animal products produced from land receiving biosolids.

EVOLUTION OF THE KING COUNTY BIOSOLIDS PROGRAM: EVALUATING CLASS A COST AND FEASIBILITY

EVOLUTION OF THE KING COUNTY BIOSOLIDS PROGRAM: EVALUATING CLASS A COST AND FEASIBILITYThe King County biosolids recycling program was initiated in the early 1970s after the passage of the Clean Water Act, which prohibited disposal of wastewater solids in water bodies. Like many municipalities at the time, King County began exploring alternatives for beneficial use of biosolids. The initial focus was on the forest, a readily available land base in the Puget Sound area. A pioneering...Author(s)John SmythPeggy LeonardSteve WilsonBill McCarthySourceProceedings of the Water Environment FederationSubjectSession 2: Product Processing and MarketingDocument typeConference PaperPublisherWater Environment FederationPrint publication date Jan, 2005ISSN1938-6478SICI1938-6478(20050101)2005:2L.112;1-DOI10.2175/193864705783968510Volume / Issue2005 / 2Content sourceResiduals and Biosolids ConferenceFirst / last page(s)112 - 125Copyright2005Word count348

SLUDGE PHYTO‐CONDITIONING: LOW‐TECHNOLOGY ENHANCED TREATMENT

ABSTRACTAgricultural recycling of biosolids is coming under increasing regulatory and non‐regulatory pressure. The UK Government and the European Commission are introducing new microbiological standards for (a) sludge, (b) expanded nitrate vulnerable zones, and (c) more stringent maximum potentially toxic element concentrations in soils. Public perception continues to play an important and unpredictable role in the acceptability of biosolids agricultural recycling. Sludge phyto‐conditioning is a low‐technology process, growing grass on sewage sludge to produce a pleasant/low‐odour compost‐like material and reducing bacterial indicators to below detectable levels, whilst retaining the beneficial energy‐recovery aspects of anaerobic digestion.This paper describes the process stream and discusses the benefits for the operator, including treatment to ‘enhanced’status and reduction in volume. The process is batch in nature and results in a high‐quality soil conditioner.

Ozone disintegration of excess biomass and application to nitrogen removal.

A pilot-scale facility integrated with an ozonation unit was built to investigate the feasibility of using ozone-disintegration byproducts of wasted biomass as a carbon source for denitrification. Ozonation of biomass resulted in mass reduction by mineralization as well as by ozone-disintegrated biosolids recycling. Approximately 50% of wasted solids were recovered as available organic matter (ozonolysate), which included nonsettleable microparticles and soluble fractions. Microparticles were observed in abundance at relatively low levels of ozone doses, while soluble fractions became dominant at higher levels of ozone doses in ozone-disintegrated organics. Batch denitrification experiments showed that the ozonolysate could be used as a carbon source with a maximum denitrification rate of 3.66 mg nitrogen (N)/g volatile suspended solids (VSS) x h. Ozonolysate was also proven to enhance total nitrogen removal efficiency in the pilot-scale treatment facility. An optimal chemical oxygen demand (COD)-to-nitrogen ratio for complete denitrification was estimated as 5.13 g COD/g N. The nitrogen-removal performance of the modified intermittently decanted extended aeration process dependent on an external carbon supply could be described as a function of solids retention time.

Sacramento's Unique Class A Biosolids Management Program Through The Design-Build Approach

Sacramento's Unique Class A Biosolids Management Program Through The Design-Build ApproachThe Sacramento Regional County Sanitation District (District) has engaged the private sector for the design, finance, construction, ownership, and 20 year operation and of a Biosolids Recycling Facility (BRF). In late 2004, the BRF will begin processing solids into heat dried pellets to be beneficially reused. The BRF is located at the Sacramento Regional Wastewater Treatment Plant (SRWTP), which...Author(s)Ruben R. RoblesJohn H. DoddsSourceProceedings of the Water Environment FederationSubjectSession 5: Biosolids ManagementDocument typeConference PaperPublisherWater Environment FederationPrint publication date Jan, 2004ISSN1938-6478SICI1938-6478(20040101)2004:16L.367;1-DOI10.2175/193864704784147458Volume / Issue2004 / 16Content sourceWEFTECFirst / last page(s)367 - 384Copyright2004Word count141

Biosolids Recycling: A Safe Practice and Sound Science in the Public Interest

Water Environment ResearchVolume 75, Issue 4 p. 291-291 Editorial Biosolids Recycling: A Safe Practice and Sound Science in the Public Interest William Bertera, William BerteraSearch for more papers by this author William Bertera, William BerteraSearch for more papers by this author First published: 01 July 2003 https://doi.org/10.1002/j.1554-7531.2003.tb00212.xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume75, Issue4July-August 2003Pages 291-291 RelatedInformation

Recycling of sewage sludge to grassland: a review of the legislation to control of the localization and accumulation of potential toxic metals in grazing systems

AbstractThe recycling of sewage sludge or biosolids to grassland is strategically important in the European Union (EU) and its use is tightly regulated to control the risk of pathogen transfer to animals and the food chain. Sewage sludges not only contain valuable concentrations of beneficial nutrients, but also elevated concentrations of potentially toxic metals (PTM) compared with average background concentrations in the soil. The EC and UK regulations refer to six PTM, Cd, Pb, Cu, Zn, Ni and Hg, with provisional regulations for Cr, that have to be controlled to prevent detrimental effects on soil and animal health. Despite these regulations, there is still a danger that grazing animals may ingest elevated concentrations of PTM. Biosolids may adhere to herbage after the surface application of sewage sludge to grassland. The repeated surface application of sewage sludge to grassland can lead to elevated concentrations of PTM at the soil surface that may be ingested, together with soil and herbage, by grazing ruminants. This may lead to accumulation of Cd or Pb in liver or kidney. The risk to the human food chain is considered to be low, but the impact on the environment is still unknown. There is little information, for example, on the amount of soil and PTMs that may become incorporated into conserved grass. At present EU and UK legislation and voluntary codes of practice have been developed to protect animal from pathogens in sewage sludge and to minimize any potential risks from accumulation of PTM. The background and implementation of the legislation are examined in this review, and the source and mechanisms of accumulation of PTM by the grazing animal are evaluated.