Advanced start up of UASB reactors by adding of water absorbing polymer

Abstract

We have developed a new approach to enhance granulation by adding water absorbing polymer (WAP) particles into the inoculated digested sludge. In this study, the effect of adding WAP on formation of anaerobic granular sludge was evaluated in lab-scale UASB reactors using two typical synthetic wastewater, i.e. glucose or volatile fatty acid (VFA) mixture solution. In addition, side by side with the lab-scale experiment, a pilot-scale experiment using the VFA mixture was carried out to evaluate the availability of accelerated start-up by adding WAP. The development of granular sludge was significantly enhanced by adding WAP. Granules developed on glucose and VFAs had high methanogenic activities and good settleability. From results of lab-scale experiment, the recommended dosage of WAP was about 750 mg/l of reactor volume. The results, pilot-scale experiment, indicated the availability of accelerated start-up by adding WAP.

Developing Aerobic Granular Sludge With Sesame Like Biodegradable Support

“…As a result of this, 50% seeds were colonized at second week to form granular biofilm (e.g., granules) from 21 days; the following days, colonization was higher 95% sesame seeds (Figure 1). In contrast with other studies, colonization of BDS was approximately 100% while these studies were not aimed high percentage of colonization with inert microcarriers [2,5]. Also, granulation process was accelerated with sesame seed like BDS such as shown the present results, overcoming start-up with other microcarriers whose granulation process was 27 days [11].…”

“…Among these advantages we can find the settling time, biomass concentration in small volumes, easy manipulation as it can be dried and stored, and the small amount of space required for application [2][3][4]. These advantages have made both organic elimination [2,5,3] and nutrient elimination (i.e., nitrogen and phosphorus, N and P, 1 Environmental Engineering Group-UC, Departamento de Ciencias y Tecnologías del Agua y el Medio Ambiente, University of Cantabria, Santander, Spain respectively) possible during sewage treatment [6][7][8], obtaining satisfactory results. At full scale, two granular processes have been performed: The CANON process and the Nereda process.…”

“…In order to fight this problem, micro-carriers have been introduced as a support to form biomass. Interestingly, some researchers have suggested using zeolites [2] or a water absorbent polymer (WAP) [5], reducing the start-up time of granular biolfilm from 1.5 months to 3 weeks [2,5,11]. However, Yoda et al, observed that between 10-40% of the microcarrier was colonized, which could be a setback and could also result in an economic loss.…”

Aplicação de coagulantes no afluente de reator anaeróbio de leito expandido alimentado com esgoto sanitário.

“…Segundo os autores, "o reator AFPB (tempo de detenção hidráulico de 2 h) reduzia a concentração de Sólidos Suspensos de 260 mg/l para 10 mg/l, DQO total de 288 para 20 m g/l, DQO solúvel de 40 mg/l para 20 mg/l, fósforo total e ortofosfatos de 2,8 e 1,6 mg/l para quase zero, em média" (SHIMIZU et al, 1994). IMAI et al (1997) (IMAI et al, 1997). SOUZA (1996), na fase de conclusão de sua pesquisa de doutoramento sobre pós-tratamento de efluente de reator anaeróbio de fluxo ascendente em reator aeróbio seqüencial em batela da e coluna de lodo anaeróbio para desnitrificação, investigou a utilização de concentrações de 90 mg/l e 200 mg/l de cloreto férrico no afluente (esgoto sintético simulando a composição de esgoto sanitário) do reator anaeróbio de seu sistema experimental.…”

Development of anaerobic immobilized-cell processes for biohydrogen production

“…He also found that the startup speed and granulation rate were accelerated via adding hydro-anthracite particles with a diameter of 100 µm (Hulshoff Pol 1989). Imai et al (1997) noted that the startup of UASB reactors were able to be enhanced while adding water absorbing polymer (WAP) particles into anaerobic digester sludge in a lab-scale study. The WAP is a pulverulent resin with particle size ranging from 100 to 200 µm, which swells in water and exhibits a complex network.…”