scholarly journals Applied Hydrothermal Carbonization

2021 ◽  
Vol 3 (4) ◽  
pp. 2750-2759
Author(s):  
Joachim Werner Zang ◽  
Warde Antonieta Da Fonseca-Zang ◽  
Stefan Reis
Keyword(s):  
Raw Materials ◽  
Carbon Sink ◽  
Chemical Conversion ◽  
Hydrothermal Carbonization ◽  
Septic Tank ◽  
Small Scale ◽  
Wet Biomass ◽  
Application Potential ◽  
Septic Tank Effluent ◽  
Great Region

The technology of hydrothermal carbonization (HTC) is a thermal chemical conversion process of organic waste into products in a reactor at low and medium temperatures and pressures, with catalysts, using residual raw materials of diversified origin, such as domestic, industrial, or agricultural. The products from the process have several energies (renewable sources) and environmental applications, such as carbon sink, soil conditioners and nanostructured materials. Implications inherent to the process, such as the type of residual biomass, the carbon phases produced (products), and adaptation of the small-scale system, have been researched in the activities. Experiences show that a laboratory-scale system transforms wet biomass from industrial waste, such as septic tank sludge, into products with application potential. The septic tank effluent originating from the great region of Goiânia was treated through hydrothermal carbonization, generating products in nanometer scale to which value could be added (potential result), in case of application at an industrial scale.   A tecnologia de carbonização hidrotermal (HTC) trata de processo de conversão termoquímica de substâncias residuárias orgânicas em produtos em reator em baixas e médias temperaturas e pressões, com catalisadores, utilizando matérias-primas residuais de origem diversificada, tais como doméstica, indústria ou agrícola. Os produtos do processo apresentam diversas aplicações energéticas (fontes renováveis) e ambientais, tais como sumidouro de carbono, condicionadores de solo e materiais nanoestruturados. Implicações inerentes ao processo, tais como o tipo de biomassa residuária, as fases de carbono produzidas (produtos) e adaptação do sistema de pequena escala, têm sido pesquisadas nas atividades. Experiências mostram que sistema em escala laboratorial transforma biomassa úmida de resíduos industriais, como lodo de fossas sépticas, em produtos com potencial de aplicação. O efluente de fossa séptica originário da grande região de Goiânia foi tratado através da carbonização hidrotermal, gerando produtos na escala nanométrica, aos quais poderiam ser agregados valor (resultado potencial), em caso de aplicação na escala industrial.

Characteristics of Hydrochars Derived from Glucose, Protein, and Cellulose by Hydrothermal Carbonization Treatment

2021 ◽  
Vol 15 (1) ◽  
pp. 97-104
Author(s):  
Peiru Zhu ◽  
Jiayang Liu ◽  
Jun Ma ◽  
Lian Li ◽  
Xueying Zhang
Keyword(s):  
Residence Time ◽  
Raw Materials ◽  
Calorific Value ◽  
Hydrothermal Carbonization ◽  
Carbon Microspheres ◽  
Wet Biomass ◽  
Bio Oil ◽  
Higher Temperature ◽  
Absolute Advantage

With hydrothermal carbonization (HTC) treatment, wet biomass can be rapidly converted into hydrochar product with high-carbon content and calorific value. The current study employed glucose, protein, and cellulose as raw materials to investigate the effects of reaction temperature and residence time on characteristics of hydrochars. Results showed that the optimal reaction temperatures for glucose, protein, and cellulose were 240 °C, 190 °C and 220 °C, respectively. The optimal residence times were 4 h, 3 h and 4 h respectively, under which carbon microspheres with smooth surface and uniform particle size tended to form. The increased temperature promoted decomposition of bio-oil in the hydrothermal system and improved the quality of carbon microspheres, but much higher temperature deformed the surface of the carbon microspheres. Appropriate residence time ensured full growth of carbon microspheres but excessive residence time made the formed carbon microspheres to crosslink with each other, causing roughness to the surface. In addition, comparison of the specific surface area showed that the cellulose carbon microspheres exhibited an absolute advantage.

Water Pollution Abatement in Small Paper Mills in India

1988 ◽  
Vol 20 (1) ◽  
pp. 37-48 ◽  
Author(s):  
L. Panneerselvam
Keyword(s):  
Water Pollution ◽  
Wastewater Treatment ◽  
Raw Materials ◽  
Pollution Abatement ◽  
Pulp And Paper ◽  
Operating Costs ◽  
Small Scale ◽  
Pulp And Paper Mills ◽  
Paper Mills ◽  
Recovery System

In order to reduce the demand for the forest based raw materials by the organised industrial sectors like the large integrated pulp and paper mills, the Government of India started promoting several small-scale pulp and paper mills based on non-wood agricultural residue raw materials. However promotion of these small mills has created another environmental problem i.e. severe water pollution due to non-recovery of chemicals. Because of the typical characteristics like high silica content etc. of the black liquor produced and the subsequent high capital investment needed for a recovery system, it is not economically feasible for the small Indian mills to recover the chemicals. While the quantity of wastewater generated per tonne of paper produced by a small mill is same as from a large integrated pulp and paper mill with a chemical recovery system, their BOD load is four times higher, due to non recovery of chemicals. However the existing wastewater disposal standards are uniform for large and small mills for e.g. 30 mg BOD/l. To meet these standards, the small mills have to install a capital intensive wastewater treatment plant with heavy recurring operating costs. Therefore the feasible alternative is to implement various pollution abatement measures, with the objective of not only reducing the fibre/chemical loss but also to reduce the investment and operating costs of the final wastewater treatment system. To illustrate this approach, a case study on water pollution abatement and control in a 10 TPD mill, will be discussed.

scholarly journals Woven-Fiber Microfiltration (WFMF) and Ultraviolet Light Emitting Diodes (UV LEDs) for Treating Wastewater and Septic Tank Effluent

Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1564
Author(s):  
Sara Beck ◽  
Poonyanooch Suwan ◽  
Thusitha Rathnayeke ◽  
Thi Nguyen ◽  
Victor Huanambal-Sovero ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Light Emitting Diodes ◽  
Domestic Wastewater ◽  
Septic Tank ◽  
Uv Disinfection ◽  
Small Community ◽  
Photochemical Process ◽  
Light Emitting ◽  
Decentralized Wastewater Treatment ◽  
Septic Tank Effluent

Decentralized wastewater treatment systems enable wastewater to be treated at the source for cleaner discharge into the environment, protecting public health while allowing for reuse for agricultural and other purposes. This study, conducted in Thailand, investigated a decentralized wastewater treatment system incorporating a physical and photochemical process. Domestic wastewater from a university campus and conventional septic tank effluent from a small community were filtered through a woven-fiber microfiltration (WFMF) membrane as pretreatment for ultraviolet (UV) disinfection. In domestic wastewater, WFMF reduced TSS (by 79.8%), turbidity (76.5%), COD (38.5%), and NO3 (41.4%), meeting Thailand irrigation standards for every parameter except BOD. In septic tank effluent, it did not meet Thailand irrigation standards, but reduced TSS (by 77.9%), COD (37.6%), and TKN (13.5%). Bacteria (total coliform and Escherichia coli) and viruses (MS2 bacteriophage) passing through the membrane were disinfected by flow-through UV reactors containing either a low-pressure mercury lamp or light-emitting diodes (LEDs) emitting an average peak wavelength of 276 nm. Despite challenging and variable water quality conditions (2% < UVT < 88%), disinfection was predictable across water types and flow rates for both UV sources using combined variable modeling, which enabled us to estimate log inactivation of other microorganisms. Following UV disinfection, wastewater quality met the WHO standards for unrestricted irrigation.

Integrated Process for Textile Cotton Waste (TCW) Valorization: Waste-to-Energy and Wastewater Decontamination

2016 ◽  
Author(s):  
A. Ribeiro ◽  
C. Vilarinho ◽  
J. Araújo ◽  
J. Carvalho
Keyword(s):  
Raw Materials ◽  
Removal Rate ◽  
Low Cost ◽  
Calorific Value ◽  
Waste To Energy ◽  
Synthetic Wastewater ◽  
Small Scale ◽  
World Population ◽  
Cotton Waste ◽  
Textile Industries

The increasing of world population, industrialization and global consuming, existing market products existed in the along with diversification of raw materials, are responsible for an exponential increase of wastes. This scenario represents loss of resources and ultimately causes air, soils and water pollution. Therefore, proper waste management is currently one of the major challenges faced by modern societies. Textile industries represents, in Portugal, almost 10% of total productive transforming sector and 19% of total employments in the sector composed by almost 7.000 companies. One of the main environmental problems of textile industries is the production of significant quantities of wastes from its different processing steps. According to the Portuguese Institute of Statistics (INE) these industries produce almost 500.000 tons of wastes each year, with the textile cotton waste (TCW) being the most expressive. It was estimated that 4.000 tons of TCW are produced each year in Portugal. In this work an integrated TCW valorisation procedure was evaluated, firstly by its thermal and energetic valorisation with slow pyrolysis followed by the utilization of biochar by-product, in lead and chromium synthetic wastewater decontamination. Pyrolysis experiments were conducted in a small scale rotating pyrolysis reactor with 0.1 m3 of total capacity. Results of pyrolysis experiments showed the formation of 0,241 m3 of biogas for each kilogram of TCW. Results also demonstrated that the biogas is mostly composed by hydrogen (22%), methane (14 %), carbon monoxide (20%) and carbon dioxide (12%), which represents a total high calorific value of 12.3 MJ/Nm3. Regarding biochar, results of elemental analysis demonstrated a high percentage of carbon driving its use as low cost adsorbent. Adsorption experiments were conducted with lead and chromium synthetic wastewaters (25, 50 and 100 mg L−1) in batch vessels with controlled pH. It was evaluated the behaviour of adsorption capacity and removal rate of each metal during 120 minutes of contact time using 5, 10 and 50 g L−1 of adsorbent dosage. Results indicated high affinity of adsorbent with each tested metal with 78% of removal rate in chromium and 95% in lead experiments. This suggests that biochar from TCW pyrolysis may be appropriated to wastewaters treatment, with high contents of heavy metals and it can be an effective alternative to activated carbon.

scholarly journals Microbial Diversity of Septic Tank Effluent and a Soil Biomat

2009 ◽  
Vol 75 (10) ◽  
pp. 3348-3351 ◽  
Author(s):  
Jill Tomaras ◽  
Jason W. Sahl ◽  
Robert L. Siegrist ◽  
John R. Spear
Keyword(s):  
Sequence Analysis ◽  
Microbial Diversity ◽  
Gene Sequence ◽  
Septic Tank ◽  
Rrna Gene ◽  
Control Soil ◽  
Rrna Gene Sequence ◽  
Gene Sequence Analysis ◽  
Site Water ◽  
Septic Tank Effluent

ABSTRACT Microbial diversity of septic tank effluent (STE) and the biomat that is formed as a result of STE infiltration on soil were characterized by 16S rRNA gene sequence analysis. Results indicate that microbial communities are different within control soil, STE, and the biomat and that microbes found in STE are not found in the biomat. The development of a stable soil biomat appears to provide the best on-site water treatment or protection for subsequent groundwater interactions of STE.

ASSESSMENT OF NITROGEN FIXATION POTENTIAL IN AHIPA (Pachyrhizus ahipa) AND ITS EFFECT ON ROOT AND SEED YIELD

2009 ◽  
Vol 45 (2) ◽  
pp. 177-188 ◽  
Author(s):  
D. N. RODRÍGUEZ-NAVARRO ◽  
M. CAMACHO ◽  
F. TEMPRANO ◽  
C. SANTAMARÍA ◽  
E. O. LEIDI
Keyword(s):  
Raw Materials ◽  
Farming Systems ◽  
Yield Potential ◽  
Small Scale ◽  
South American ◽  
Field Inoculation ◽  
Promising Alternative ◽  
Yield Increase ◽  
Alternative Crop ◽  
Attractive Option

SUMMARYAhipa is a legume of great interest for the production of raw materials (starch, sugar, oil and proteins) for industrial use. Its yield potential and ability to fix atmospheric N2 in association with rhizobia makes it an attractive option for low input agriculture systems. At present, it is cultivated on a very small scale as a food crop in a few South American countries. Little information is available on symbiotic N2 fixation in ahipa and no work has been performed on strain selection for inoculant production. Soils in southwest Europe are devoid of specific rhizobia able to nodulate on ahipa. Selecting rhizobia for symbiotic effectiveness from a collection led to the isolation of strains which provided greater shoot growth and N content under controlled conditions. In the field, inoculation at sowing with the selected strains increased significantly seed and tuberous root yield and seed protein content. The amount of N2 fixed, estimated by 15N natural abundance, reached 160–260 kg N ha−1. In previous work, ahipa appeared to be a promising alternative crop for the production of industrial raw materials. The results of the present study showed a yield increase in tuberous roots and seeds when applying effective rhizobia inoculants. Furthermore, a positive soil N balance was left after its cultivation making ahipa even more interesting for sustainable farming systems.

COMPARATIVE TECHNICAL AND ECONOMIC ESTIMATION OF THE SMALL-SCALE ON-FARM COMPOUND FEED PLANTS

2021 ◽  
pp. 59-65
Author(s):  
SERGEY V. BRAGINETS ◽  
Keyword(s):  
Net Present Value ◽  
Raw Materials ◽  
Farm Animals ◽  
Small Scale ◽  
Hammer Mill ◽  
Capital Investments ◽  
Agricultural Enterprises ◽  
Feed Production ◽  
Effi Ciency ◽  
On Farm

On-farm compound feed production from self-produced raw materials is favorable to agricultural enterprises under present-day conditions. The authors carried out a comparative technical and economic study of the conventional and modular small-scale on-farm compound feed plants with a capacity of 2 tons per hour, designed for agricultural enterprises with an average livestock population of 6…8 thousand pigs. The proposed modular plant consists of two modules – the operative storage of raw materials and the main module of grinding and mixing. Modules with installed equipment are delivered and placed on a light foundation, connected by transport equipment and with tanks for raw materials and fi nished products. The conventional factory is a technological line housed in a hangar and used for crushing, metering, and mixing raw materials. It consists of a separator, a hammer mill, weighing equipment, a mixer, containers for raw materials and fi nished products, transport, and aspiration equipment. The technical and economic analysis has shown that the erection and operation of the on-farm modular enterprise require 41% less capital investments than a traditional compound feed plant of the same capacity. The use of a small-scale modular plant will reduce operating costs by 23.8% (from 3094 to 2358 thousand rubles), increase the specifi c economic eff ect from the compound feed production by 1.6% (from 8.64 to 8.78 thousand rubles per ton) and return on margin by 4% (from 10.2 to 10.6%), reduce the payback period by 42% (from 0.8 to 0.46 years), and increase the net present value by 3% (from 66167 to 68216 thousand rubles), as compared to a conventional enterprise. The modular on-farm plants producing loose compound feed with a productivity of up to 3 tons per hour are profi table and economically sound as they can increase production effi ciency of compound feeds for farm animals.`

Septic Tank Effluent Treatment Using Laboratory-Scale Peat Filters

1994 ◽  
Vol 29 (1) ◽  
pp. 19-38 ◽  
Author(s):  
R.N. Coleman ◽  
I.D. Gaudet
Keyword(s):  
Fecal Coliform ◽  
Loading Rate ◽  
Microbial Colonization ◽  
Effluent Treatment ◽  
Septic Tank ◽  
Upward Flow ◽  
Septic Tank Effluent ◽  
Flow Treatment ◽  
Coarse Gravel ◽  
Bod Removal

Abstract Filter columns were designed, constructed from sand, peat and coarse gravel, and their effectiveness assessed in the treatment of septic tank effluent. An initial loading rate of 4 cm/d was applied to the filter columns in either a downward or upward flow at a temperature of 10°C or 20°C. The loading rate was later increased to 8 cm/d. Filter-column plugging occurred in the downward flow treatment but not in the upward flow treatment. Fecal Coliform removal was usually greater than 95%, BOD removal was greater than 75%, and various removal levels were exhibited for other components. Microbial colonization of peat and gravel was effective as revealed by scanning electron microscopy.

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