Bioconversion of Organic Residues for Rural Communities (UNU, 1979): The role of ruminants in the bioconversion of tropical byproducts and wastes into food and fuel: An integrated system for converting tropical feeds and byproducts into milk, beef, and fuel

Bioconversion of Organic Residues for Rural Communities (UNU, 1979)

From the charter of the United Nations University

Foreword

Perspectives on bioconversion of organic residues for rural communities

(introductory text...)

Introduction

Sources of available nutrients

The most suitable materials for bioconversion

Characteristics of residues

Bioconversion systems

Physical and chemical treatments

Microbial conversion

The animal conversion phase

Summary

References

Availability of organic residues as a rural resource

(introductory text...)

Discussion summary: Papers by van der Wal and Barreveld

Micro-organisms as tools for rural processing of organic residues

(introductory text...)

Introduction

Microbial utilization of mono- and di-saccharide residues

Microbial conversion of starchy residues

Microbial conversion of complex mixtures of compounds (Polysaccharides, Proteins, Lipids, etc.)

Microbial utilization of cellulose and ligno-cellulose residues

Algal culture as a source of biomass

Microbial utilization of silviculture biomass

Micro-organisms and marine and freshwater biomass

International studies on processing organic residues

References

Production of feed as an objective for bioconversion systems

(introductory text...)

Introduction

General characteristics

Manure as feed

Sewage-grown micro-algae

Conclusion

References

Environmental goals for microbial bioconversion in rural communities

(introductory text...)

Introduction

Health and water economy

Fertilizer and energy economy

Concluding remarks

References

Discussion summary: Papers by Porter, Berk and La Rivière

Strategies for developing small-scale fermentation processes in developing countries

(introductory text...)

References

Discussion summary

Production of microbial protein foods on edible substrates, food by-products, and ligno-cellulosic wastes

(introductory text...)

Preface

Introduction

Contributions to the solution of nutritional problems

Development of protein-rich vegetarian meat substitutes in the western world

References

Discussion summary

The role of ruminants in the bioconversion of tropical byproducts and wastes into food and fuel

(introductory text...)

Introduction

Nutritional limitations in the use of tropical by-products and waste

Practical experience with tropical by-products and wastes as feed for ruminants

An integrated system for converting tropical feeds and byproducts into milk, beef, and fuel

References

Discussion summary

Possible applications of enzyme technology in rural areas

(introductory text...)

Introduction

Biocatalytic processes

Enzyme hydrolysis of manioc

Whole cell systems

Cellulose degradation and utilization

Transfer of enzyme technology to rural communities

Conclusions

References

Discussion summary

Indian experience with treated straw as feed

(introductory text...)

Introduction

Experience with straw treatment

Field testing and demonstration of straw treatment

General considerations

Summary

Annex 1. The energy efficiency of the two-stage, feed-fuel processing of straw in indian villages

Annex 2. Method of calculating the value presented in table 2 for the efficiency of naoh energy usage

Annex 3. Recommendations to farmers on the treatment of straw

Annex 4. Calculated efficiency of milk production by straw-fed village buffaloes

References

Discussion summary

Indian experience with algal ponds

(introductory text...)

Introduction

Cultivation of algae in wastes for feed

Problems of contamination

Cultivation of algae for biofertilizer

References

Acknowledgements

Discussion summary

Organic residues in aquaculture

(introductory text...)

Introduction

The range of production in aquaculture

The value of organic wastes

Direct feeding

Concluding remarks

References

Discussion summary

Biogas generation: developments. Problems, and tasks - an overview

(introductory text...)

Introduction

What is biogas?

Microbiology of CH4, or bio-methanogenesis

The biogas plant-some technical considerations

Environmental and operational considerations

Developments and processes for rural areas

Cost-benefit analyses

Health hazards

Bottlenecks, considerations, and research and development

References

Discussion summary

Mushroom production technology for rural development

(introductory text...)

Materials and methods for growing mushrooms under natural or field conditions

Growing mushrooms under semicontrolled conditions

Results and discussion

References

Discussion summary

The combination of algal and anaerobic waste treatment in a bioregenerative farm system

(introductory text...)

Introduction

Algae production on organic wastes

The bioregenerative farm

References

Discussion summary

A continuous composting system for disposal and utilization of animal wastes at the village level

(introductory text...)

Status of land utilization and disposal of animal wastes

A continuous composting system for land utilization of animal wastes at the village level

References

Bioconversion of fruit and vegetable wastes

(introductory text...)

State of the art of bioconversion

Technical transfer

Integrated research on agricultural waste reclamation

(introductory text...)

Introduction

Production of yeast from soybean cooking waste at miso factories

Application of soy waste as koji substrate for rice miso manufacturing (5, 6)

Conclusion

References

Discussion summary

Solid state fermentation of starchy substrates

(introductory text...)

Introduction

Materials and methods

Agro-economic perspectives

Summary

References

Discussion summary

Production of single-cell protein from cellulose

(introductory text...)

Introduction

Experimental results

Discussion

Summary

References

Acknowledgements

Discussion summary

Analysis of energy cost of integrated systems

(introductory text...)

Energy cost and energy requirement

Why energy analysis?

Net energy intensity

What criteria are offered by energy analysis?

Conclusion

References

Analysis of bioconversion systems at the village level

(introductory text...)

Introduction

Approach to bioconversion analysis

Some results and costs from integrated systems

Future development possibilities

Conclusions

Summary

References

Nutritional evaluation of bioconversion products for farm animals

(introductory text...)

Introduction

Testing procedures for determination of nutritional value

Bioconversion products: toxicology - problems and potential

(introductory text...)

Summary

References

Nutritional evaluation in humans

(introductory text...)

Introduction

Evaluation of products of bioconversion for human consumption

Procedures for nutritional evaluation in humans

The evaluation of various food products

Concept of productivity

Conclusions

References

Discussion summary: Papers by van Weerden, Shacklady, and Bressani

Biomass from organic residues for animal and human feeding

(introductory text...)

References

Discussion summary

Appropriate biotechnology - summary remarks

(introductory text...)

References

Other UNU Publications

(introductory text...)

Books

An integrated system for converting tropical feeds and byproducts into milk, beef, and fuel

Having identified the nutritional constraints associated with the use of tropical byproducts, it becomes possible to plan efficient systems for converting these into animal products such as beef and milk. This task also has been facilitated considerably by the recent findings that both by-pass protein and desired roughage characteristics can be provided by such protein-rich tropical forages as the legume shrub Leucaena leucocephala, the leaves of the banana plant, and the aerial forage part of the sweet potato (2, 13, 14). Cassava forage is also effective with one specific tropical by-product, namely molasses (15).

The likely input-output relationships involved in a rural bioconversion unit using cattle can be appreciated from the data in Table 4. It is assumed that a single family unit has 1.5 ha of land and that it will derive its disposable income from the sale of bananas, milk or cheese, and beef. The cattle population comprises five adult cows, four calves, and four steers/heifers. The cattle are confined throughout the year in an open-side building fitted with a partially slatted floor so that the faeces and urine fall directly into a channel below the floor, which, in turn, connects with the inlet of a biogas digester. After partial digestion, the final effluent is pumped onto the crops as a fertilizer (see Figure 4). The same equipment is used to apply irrigation water. The biogas produced from the unit (about 5.7 m³/day) is calculated to be sufficient to provide for cooking in the house and to drive the irrigation/effluent pump and forage chopper.

TABLE 4. Input-Output Relationships in a Rural Bioconversion Unit Using Cattle

Figure. 4. Layout of Proposed Family Unit Incorporating Direct Food Crop Production and Bioconversion of Wastes through Cattle

The cattle are fed a mixture of sugar-cane (high biomass per unit area), and banana forage - i.e., the residue after harvesting the fruit, as the energy source, and sweet potato forage for by-pass protein. No roots are harvested and the plant is managed as a perennial. Some additional nonprotein nitrogen such as urea, and phosphorus-rich minerals and salt are purchased; these are the only imports into the unit. Both the banana forage and sweet potato forage provide desirable roughage characteristics.

The advantages of this particular system are that it:

a. provides a good level of disposable income for the family;
b. is likely to be in energy balance (except for the energy cost of the urea and minerals);
c. avoids erosion by using perennial forages and by recycling organic matter;
d. relies to a minimum on imported fertilizer, yet represents a high level of plant nutrient application because of recycling;
e. reduces environmental contamination; and
f. uses a minimum of land area (1.5 ha), yet produces both a cash crop and animal products.