Bioslurry Utilization and Handling Methods

Transcription

1 Bioslurry Utilization and Handling Methods Fentaw Ejigu (original Amharic) Yoseph Garedew (English translation) Institute for Sustainable Development Addis Ababa in collaboration with Ministry of Water and Energy Alternate Energy Technology Promotion Directorate National Biogas Programme of Ethiopia

2 Publisher Institute for Sustainable Development PO Box 171, code 1110, Addis Ababa, Ethiopia Tel: +251-(0) / Fax: +251-(0) sustaindeveth@ethionet.et Website: Institute for Sustainable Development 2012 This publication can be shared for education and training, but it cannot be used for profit or any other commercial purpose. Acknowledgement of the publisher and associates is appreciated. Support for this publication came from the National Biogas Programme of Ethiopia (NBPE) that receives financial and technical support from SNV, the Netherlands Development Agency. NBPE is based in the Alternate Energy Technology Promotion Directorate of the Ministry of Water and Energy, Federal Democratic Republic of Ethiopia Editors: Hailu Araya, Yosef Garedew & Sue Edwards Artist: Sissay Kebede Cover design: Binyam Woldu

3 W/ro Muchit, W/ro Elfinesh and W/ro Alemitu are discussing how they live and support themselves W/ro Elfinesh W/ro Muchit W/ro Alemitu, you look very happy these days. Can you share with us your secret? W/ro Alemitu Yes, you are right. W/ro Alemitu should share with us the secret of her success. Even her crops have improved. Yes you are right. I m very happy these days. The secret of my happiness is using a biogas digester. After I started using the biogas, I no more suffer from smoke when I am cooking. My children and I no longer have to use our time for collecting dung and firewood to use as fuel. Besides; I saved money from the last two years crop yield. It is because I used the bioslurry as an input for making compost. 1

4 What is biogas and bioslurry? Biogas is produced from mixing equal quantities of animal dung and water, and pouring these through a special opening into the biogas digester where there is no oxygen. In the biogas digester, special bacteria that come from the stomach of the animals and stay in the animal dung break down the dung and produce biogas. The gas is used to cook food and make a light. After the gas is produced, the residue comes out through the outlet. It is called bioslurry. It is very useful., as I will explain to you. 2

5 W/ro W/ro Elfinesh Muchit W/ro Alemitu This is the biogas digester This is where the dung and water are mixed and fed into the inlet This is the biogas burning light This is the biogas cooking stove 3

6 This is the meter to show the amount of gas produced. We control the use of the gas with its gauge meter and know when it is full or empty. When we cook using biogas, the kitchen is free from smoke. Since the biogas digester is connected with the toilet it improves the hygienic conditions for the whole family. This is the bioslurry container. This shows the place of the biogas digester next to the house and toilet 4

7 W/ro Alemitu, what is the use of bioslurry? USES OF BIOSLURRY It provides different kinds of plant foods (nutrients) for the growth of healthy plants It improves the soil structure so that air and water can move through the soil so the plants have healthy roots It improves the fertility of the soil that contributes to better crop yields. How is slurry used? 5

8 BIOSLURRY CAN BE USED IN DIFFERENT WAYS 1. I can use it directly as a liquid and pour it around the base of fruit trees and in between rows and around vegetable plants. Liquid slurry can be applied by using buckets and jerry cans Look, I produced these fruits and vegetables by using bioslurry 6

9 However instead of using fresh bioslurry, it is better to take and store it out of the tank for a few days and then dilute it with water before pouring it on seedlings or young plants. Cover the bioslurry with straw or dried grass to stop the nutrients from evaporation into the open air, particularly after the bioslurry is poured around the plants. In the rainy season or where irrigation is available, the slurry can be mixed with the irrigation water. It can be used to produce many different types of crops and fodder for domestic animals. Mixing bioslurry with water 7

10 The diluted slurry can be used for animal fodder production, different crops, fruits and vegetables. Animal fodder Crops 2. It can be used for controlling pests and diseases in the field Last year my neighbor, Ato Kebede, used it as pest control on his cabbage garden when the cabbages were attacked by aphids and caterpillars. 3. Pelleting/coating seeds with bioslurry before sowing Before sowing, seeds can be dipped into liquid bioslurry and then dried to get a covering of bioslurry. Coating seeds with bioslurry before they are sown helps them germinate faster and get nutrients. Moreover, it helps prevent the seeds and seedlings from being attacked by diseases and pests. 8

11 4. It is used as an accelerator in decomposition for making compost The bacteria and other micro organisms from inside the biogas digester come out with the slurry and help in the fast decomposition of the slurry and other materials added to make quality compost. The time to make compost is also reduced. 5. Bioslurry is changed into quality compost for use in fields and selling to other farmers Transporting bioslurry in liquid form to fields is difficult. We prepare compost by mixing the bioslurry with other farm and households waste materials and then store it for use later or for selling. My husband Beyene can tell you better about the preparation and use of compost. Good! That is the best idea, so why don t we let our husbands meet and talk about it? 9

12 Great! Let them meet at Beyene s farm and exchange ideas. Good morning Beyene, how good your wheat crop is looking! Well, it is indeed good and healthy because I used compost made from bioslurry. What did you use to have such beautiful wheat? 10

13 Ok, please could you tell us about bioslurry compost? The bioslurry compost is prepared by mixing the bioslurry with other wastes from the farm, garden and kitchen. It is changed to compost with the help of bacteria and micro organisms such as earthworms and termites. Is that the only reason for the high performance of the crop? 11

14 Of course yes. But you need to do the composting process in an organized way Surprising! Can you tell us more about how to prepare it? There are two composting methods. One is the conventional composting method and the other one is done by digging two compost pits near to the bioslurry tank. 12

15 Making compost in bioslurry receiving pits Compost making pits The size of the two pits is equal to the size of the biogas digester, for example, for a 6m3 digester, the compost making pits should be 3m3 each. The pits are filled by turns. Each time the bioslurry flows into the pit, other composing materials like left over fodder, animal bedding, weeds, dry plants and other materials are put on top of it. The decomposing material should be enough to absorb the liquid in the bioslurry. This process is repeated until the pit is full to the top and then it can be covered with a layer of soil and large leaves to protect it. When the first pit is full, the bioslurry flow is fed into the second pit. The compost digesting/making process in the first pit is usually finished when the second compost making pit is full. 13

16 What about the second compost making method? We dig one or two pits in a different place and smear the walls and the floor of the pit with the bioslurry. Having done that, we put in the various materials such as old straw, weeds, waste materials from preparing food, etc, in layers and pour the slurry over these. This has to be done in sequence until the pit is full. This is the same as the common compost preparation method except that the bioslurry replaces the mixture of animal dung and water. Pits for conventional compost preparation 14

17 After digging the compost pit, the wall and floor of the pit is plastered with bioslurry. Old sorghum and maize stalks Different materials for making compost Weeds and other green plant material Old animal bedding and straw Breaking up the bigger pieces of plant material 15

18 How much of the wet and how much of the dry materials? The dry materials make up about 2/3rds while the wet materials are about 1/3rd I now understand the compost making process but how do we know whether the compost is well fermented or not? How can we use the matured compost? 16

19 Well fermented compost has the following properties: It is dark brown to black with a good smell like freshly dug fertile soil You cannot see any of the original plant materials It crumbles /breaks into pieces like bread crumbs You find friendly micro-organisms such as earth worms in it Take care to cover the mature compost so it is not exposed to sun or rain before you want to use it The finished compost is under the shade of a tree and/or kept in the pit until it is used 17

20 HOW TO USE THE COMPOST The compost can be scattered on the field like broadcast sowing of crops It can be put in the hole when the fruit and tree seedlings are planted out For crops planted in rows, the compost is put in the row at the same time as the seed 18

21 Ato Beyene, is there any problem if we apply the compost before the sowing date when there is no shortage of people to help? Yes. The nutrients will be lost if you apply the compost earlier than the right time: that is at the same time as planting the crop. This was very good advice for us. The main problem we see is the difficulty in digging the pits. 19

22 Compost can also be prepared without digging a pit. Come and look here. The materials can be piled up on top of the ground like this. The order of the layers of the input material is the same as for making compost in the pit. So why is it necessary to dig a pit? 20

23 Making compost in a pile is possible where water is easily available and it is wet most of the year. But a pit is better where there is a very dry season as it keeps the compost making process moist. It can also protect the compost from flooding when it rains. Thank you. We will start making compost very soon. 21

24 I forgot one thing. When you select a place for preparing compost, it should be protected from wind, sun and floods. If excess water gets in to the pit, the compost materials would not be decomposed and there would be washing out of the nutrients. Wind and sun can dry up the compost and the nutrients also get lost. The preferable place for compost making is in the shade under a tree. 22

25 If there are no good trees, it is necessary to make a shade over the compost pits or piles. The mature compost should be protected in a storage area, even kept inside a small shed or room, until it is used. 23

26 For your own notes 24