title: Protein intercalated bentonite recovered using adsorption from stickwater

authors: Verbeek, Casparus Johan R.

subjects: bentonite

abstract: Wastewater from the meat rendering industry is called stickwater and contains about 4 wt% protein and has a high biological oxygen demand (approximately 150,000 mg/l). Large volumes require treatment prior to disposal, leading to a potentially useful source of protein being lost. In this study the organic fraction of stickwater (largely protein) was recovered by adsorption onto bentonite followed by centrifugation. Adsorption behavior was examined for a range of pH and clay concentrations. Equilibrium behaviour was described using the Langmuir–Freundlich isotherm. 25% organics can be recovered from stickwater without clay at pH below 5. Organic matter recovery was between 75 and 90% at 1 g clay per 20 g solution. Recovery decreased with increasing pH above pH 7–25% at pH 12, but was independent of pH at higher clay concentrations. Bentonite basal spacing increased from 13 to 23.5 Å for all pHs showing that protein had intercalated between clay layers. At high pH, bentonite had a positive charge on its edges, giving an expanded structure with a low pellet density at 17% solids, whereas at pH below 5 pellet density was between 25 and 33% solids. This has implications for downstream processing because more water would need to be removed, increasing downstream processing costs. Using between 5 and 10 g clay/200 g solution, adsorption was sufficient to give greater than 60% organics recovery. Processing would therefore be a trade off between using as as little as possible clay to minimise cost and maximise percentage organics adsorbed per gram of clay, while maximising recovery and maintaining small process volumes.

text: Protein intercalated bentonite recovered using adsorption from stickwater Wastewater from the meat rendering industry is called stickwater and contains about 4 wt% protein and has a high biological oxygen demand (approximately 150,000 mg/l). Large volumes require treatment prior to disposal, leading to a potentially useful source of protein being lost. In this study the organic fraction of stickwater (largely protein) was recovered by adsorption onto bentonite followed by centrifugation. Adsorption behavior was examined for a range of pH and clay concentrations. Equilibrium behaviour was described using the Langmuir–Freundlich isotherm. 25% organics can be recovered from stickwater without clay at pH below 5. Organic matter recovery was between 75 and 90% at 1 g clay per 20 g solution. Recovery decreased with increasing pH above pH 7–25% at pH 12, but was independent of pH at higher clay concentrations. Bentonite basal spacing increased from 13 to 23.5 Å for all pHs showing that protein had intercalated between clay layers. At high pH, bentonite had a positive charge on its edges, giving an expanded structure with a low pellet density at 17% solids, whereas at pH below 5 pellet density was between 25 and 33% solids. This has implications for downstream processing because more water would need to be removed, increasing downstream processing costs. Using between 5 and 10 g clay/200 g solution, adsorption was sufficient to give greater than 60% organics recovery. Processing would therefore be a trade off between using as as little as possible clay to minimise cost and maximise percentage organics adsorbed per gram of clay, while maximising recovery and maintaining small process volumes.

year: 2011

title: The atomisation of the American Left: The unravelling of collectivism in protesting United States’ Foreign Policy

authors: Mikkelson, Vaughan

abstract: This thesis addresses the question: has the rise of postmodernism and the New Social Movements essentially undermined and “individuated” the traditionally collectivist American Left?  The thesis seeks to address the shift of degree, if any, of the American Left’s character as a collective force of dissent regarding, primarily, U.S. foreign policy.  The approach of this thesis has been to examine two indicative and comparative case studies, two left-leaning activist groups that emerged spontaneously in the 1980s and 2000s in one of the most conservative areas of the United States, with a view to determining the impact of postmodernism and the New Social Movements on the attitudes and behaviours of the group members.  The approach taken, for the purposes of this thesis, has been to investigate through non-random interviews, based upon an open-ended questionnaire, these activist groups protesting U.S. Foreign Policy.  The research findings posit that the American Left has become atomised in regards to the central question and the rise of postmodernism and the New Social Movements have undermined and ‘individuated’ the traditionally collectivist American Left.  This has been evident for some time as the diffusion of the New Social Movements from the 1970s onwards has seen the Left fragment into single issue groups.  The American Left has become individuated and has migrated away from collectivism to what appears to be a postmodern sensibility, placing ever greater emphasis on self-development and individuality. The American Left has apparently retreated into forms of localism. For example: issues pertaining to municipalities, the academy and  the arts.  Also, the Left has had a visible presence through single-issue platforms such as: the environmental movement, the anti-nuclear movement, gay and lesbian rights and the feminist movement, to name but a few.  Neo-liberals have strongly espoused free market doctrines from a fundamentalist perspective. Neoconservatives have advocated a vision for U.S. foreign policy based on “American values” and the projection of the Liberal “Democratic” project. Neoconservatives, too, possess a fundamentalist ardour. The American Left, by contrast, has found itself perpetually in defensive mode. Generally speaking, American leftists are supporters of the U.S. Democratic Party. The trajectory of the Democratic Party may be seen as having advocated for the cultural Left on the fringes of its social policy platform. However, few voices that espouse traditional Leftist values remain in its ranks.  Therefore, the American left remains a voice in the wilderness buffeted by both the forces of Liberalism and Conservatism.

text: The atomisation of the American Left: The unravelling of collectivism in protesting United States’ Foreign Policy This thesis addresses the question: has the rise of postmodernism and the New Social Movements essentially undermined and “individuated” the traditionally collectivist American Left?  The thesis seeks to address the shift of degree, if any, of the American Left’s character as a collective force of dissent regarding, primarily, U.S. foreign policy.  The approach of this thesis has been to examine two indicative and comparative case studies, two left-leaning activist groups that emerged spontaneously in the 1980s and 2000s in one of the most conservative areas of the United States, with a view to determining the impact of postmodernism and the New Social Movements on the attitudes and behaviours of the group members.  The approach taken, for the purposes of this thesis, has been to investigate through non-random interviews, based upon an open-ended questionnaire, these activist groups protesting U.S. Foreign Policy.  The research findings posit that the American Left has become atomised in regards to the central question and the rise of postmodernism and the New Social Movements have undermined and ‘individuated’ the traditionally collectivist American Left.  This has been evident for some time as the diffusion of the New Social Movements from the 1970s onwards has seen the Left fragment into single issue groups.  The American Left has become individuated and has migrated away from collectivism to what appears to be a postmodern sensibility, placing ever greater emphasis on self-development and individuality. The American Left has apparently retreated into forms of localism. For example: issues pertaining to municipalities, the academy and  the arts.  Also, the Left has had a visible presence through single-issue platforms such as: the environmental movement, the anti-nuclear movement, gay and lesbian rights and the feminist movement, to name but a few.  Neo-liberals have strongly espoused free market doctrines from a fundamentalist perspective. Neoconservatives have advocated a vision for U.S. foreign policy based on “American values” and the projection of the Liberal “Democratic” project. Neoconservatives, too, possess a fundamentalist ardour. The American Left, by contrast, has found itself perpetually in defensive mode. Generally speaking, American leftists are supporters of the U.S. Democratic Party. The trajectory of the Democratic Party may be seen as having advocated for the cultural Left on the fringes of its social policy platform. However, few voices that espouse traditional Leftist values remain in its ranks.  Therefore, the American left remains a voice in the wilderness buffeted by both the forces of Liberalism and Conservatism.

year: 2012

title: Waiwhakareke Restoration Plantings: Establishment of Monitoring Plots 2005-06

authors: Grove, E.

subjects: New Zealand

abstract: Waiwhakareke Natural Heritage Park is being developed to reconstruct native lowland and wetland ecosystems as were once widespread in the Waikato Region. The 60ha Natural Heritage Park is located on the north-west outskirts of Hamilton City and includes a peat lake (Horseshoe Lake) which is surrounded by introduced willow trees. There is some native marginal vegetation around the lake, including rushes and sedges, and an extensive area of gently sloping pasture completes the catchment. The restoration and recreation of the native plant and animal communities is being lead by the Hamilton City Council in partnership with The University of Waikato, Wintec, Nga Mana Toopu o Kirikiriroa Limited Resource Management and Cultural Consultants and Tui 2000 (McQueen 2005; McQueen & Clarkson 2003).

text: Waiwhakareke Restoration Plantings: Establishment of Monitoring Plots 2005-06 Waiwhakareke Natural Heritage Park is being developed to reconstruct native lowland and wetland ecosystems as were once widespread in the Waikato Region. The 60ha Natural Heritage Park is located on the north-west outskirts of Hamilton City and includes a peat lake (Horseshoe Lake) which is surrounded by introduced willow trees. There is some native marginal vegetation around the lake, including rushes and sedges, and an extensive area of gently sloping pasture completes the catchment. The restoration and recreation of the native plant and animal communities is being lead by the Hamilton City Council in partnership with The University of Waikato, Wintec, Nga Mana Toopu o Kirikiriroa Limited Resource Management and Cultural Consultants and Tui 2000 (McQueen 2005; McQueen & Clarkson 2003).

year: 2006