Date of Award

Spring 2-28-2020

Semester of Degree


Document Type

Open Access Thesis

Degree Name

M.S. in Paper and Bioprocess Engineering


Environmental and Forest Biology

Major Professor

Bandaru Ramarao

Steering Committee Member

Thomas E Amidon

Steering Committee Member

Shijie Liu

Steering Committee Member

Gary Scott

Steering Committee Member

Bandaru Ramarao

Steering Committee Member

Gyu Leem


Lignocellulosic hydrolysates contain significant amount of colloidal lignin and its removal is vital since it inhibits fermentation, hinders oligomer hydrolysis and affects filtration. Flocculation of lignin prior to filtration is viable and previous research (Yasarla & Ramarao, 2012) demonstrated PEO’s ability to form complexes with lignin in the hydrolyzate. PEO viscosity was determined precisely to use as a control variable for flocculant quality. Flocculation efficiency of PEO in hydrolyzates was studied using parameters such as supernatant turbidity, sedimentation rate, filtration rate and cake permeability. Concentrations, dosages and molecular weights of PEO during flocculation were varied to study its effects. Multicomponent flocculation using APAM and p- DADMAC demonstrated better lignin removal than PEO flocculation. Addition of wood pulp as a filter media to PEO was based on incorporating both flocculation and filtration as a single operation. A depth filtration model was fitted using assumed parameters to obtain concentration profile and filter efficiency.

Included in

Engineering Commons