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 "worksheets": [

  {

   "cells": [

    {

     "cell_type": "heading",

     "level": 1,

     "metadata": {},

     "source": [

      "Chapter08:Biomass Energy"

     ]

    },

    {

     "cell_type": "heading",

     "level": 2,

     "metadata": {},

     "source": [

      "Ex8.1:pg-271"

     ]

    },

    {

     "cell_type": "code",

     "collapsed": false,

     "input": [

      "import math\n",

      "# given data\n",

      "Gascook=5*0.227 # gas required for cooking in m^3/day\n",

      "Gaslight=0.126*2*3 # gas required for lighting in m^3/day\n",

      "Totalgasreq=Gascook+Gaslight # in m^3/day\n",

      "gasperday=0.34*0.18*7 # in m^3/day\n",

      "\n",

      "n=1+Totalgasreq/gasperday # no. of cows\n",

      "print \"The number of cows is \",int(n)\n",

      "cowfeed=7*n # in kg\n",

      "slurry=cowfeed*2.0/1090 # in m^3\n",

      "totalslurry=50.0*slurry # in m^3\n",

      "reqvolume=totalslurry/0.9 \n",

      "print \"The total volume of digester is \",round(reqvolume,2),\"m^3\""

     ],

     "language": "python",

     "metadata": {},

     "outputs": [

      {

       "output_type": "stream",

       "stream": "stdout",

       "text": [

        "The number of cows is  5\n",

        "The total volume of digester is  3.86 m^3\n"

       ]

      }

     ],

     "prompt_number": 9

    },

    {

     "cell_type": "heading",

     "level": 2,

     "metadata": {},

     "source": [

      "Ex8.2:pg-272"

     ]

    },

    {

     "cell_type": "code",

     "collapsed": false,

     "input": [

      "import math\n",

      "# given data\n",

      "Gaslight=10*0.227*4 # gas required for lighting in m^3/day\n",

      "Eleccomp=10*250*6*60*60/1000000.0 # electrical energy required by computers in MJ\n",

      "effith=0.25 # thermal efficieny\n",

      "efficonv=0.80 # conversion efficiency\n",

      "Heat=23.0 # heating value of biogas in MJ/m^3\n",

      "rho=1090.0 # slurry density in kg/m^3\n",

      "Engineinput=Eleccomp/(effith*efficonv)\n",

      "\n",

      "energypump=746*2*2*60*60/1000000.0 # mechanical energy required for pumping in MJ\n",

      "themalinput=energypump/effith  # required thermal input in MJ\n",

      "totalinput=themalinput+Engineinput # total thermal input required by engine\n",

      "\n",

      "Volreq=totalinput/Heat # volume required per day in m^3/day\n",

      "Totalrq=Volreq+Gaslight # total gas required in m^3 /day\n",

      "\n",

      "n=Totalrq/(7*0.18*0.34) # solid mass is 18% and n is number of cows required\n",

      "n=round(n)\n",

      "print \"The number of cows is\",n\n",

      "feed=7*n # daily feed in kg\n",

      "slurry=2*feed # in kg\n",

      "volslurry=slurry/rho # volume of slurry added per day in m^3\n",

      "totalvol=50*volslurry/0.9 # total volume for 50 days in m^3 when 90 % is occupied by slurry\n",

      "\n",

      "print \"The size of biogas plant is \",round(totalvol,2),\"m^3\"\n",

      "\n",

      "\n",

      "\n",

      "\n"

     ],

     "language": "python",

     "metadata": {},

     "outputs": [

      {

       "output_type": "stream",

       "stream": "stdout",

       "text": [

        "The number of cows is 53.0\n",

        "The size of biogas plant is  37.82 m^3\n"

       ]

      }

     ],

     "prompt_number": 8

    },

    {

     "cell_type": "heading",

     "level": 2,

     "metadata": {},

     "source": [

      "Ex8.3:pg-273"

     ]

    },

    {

     "cell_type": "code",

     "collapsed": false,

     "input": [

      "import math\n",

      "# given data\n",

      "Voldaily=1200 # daily production in m^3/day\n",

      "prodrate=Voldaily/24.0 # gas production rate per hour\n",

      "consrate=Voldaily/6.0 #gas consumtion rate per hour\n",

      "Vg1=(consrate-prodrate)*2 # gas holder size required for 2 hours in litres\n",

      "Vg2=prodrate*9 # gas holder size for 9 hours without consumption in litres\n",

      "if Vg1>Vg2:\n",

      "    Vgmax=Vg1\n",

      "else:\n",

      "    Vgmax=Vg2\n",

      "Vg=Vgmax*1.25 # required gas holder with 25 % safety margin in litres\n",

      "print \"required gas holder size is \",Vg,\"litres\"\n",

      "Capacity=Vg/Voldaily # required gas holder capacity\n",

      "\n",

      "print \"required gas holder capacity is \",round(Capacity*100,2),\"%\"\n",

      "    \n"

     ],

     "language": "python",

     "metadata": {},

     "outputs": [

      {

       "output_type": "stream",

       "stream": "stdout",

       "text": [

        "required gas holder size is  562.5 litres\n",

        "required gas holder capacity is  46.88 %\n"

       ]

      }

     ],

     "prompt_number": 11

    },

    {

     "cell_type": "heading",

     "level": 2,

     "metadata": {},

     "source": [

      "Ex8.4:pg-274"

     ]

    },

    {

     "cell_type": "code",

     "collapsed": false,

     "input": [

      "import math\n",

      "# given data\n",

      "drymattrprd=2 # dry matter produced in kg/day/cow\n",

      "gasyield=0.22 # biogas yield in m^3 /kg\n",

      "drymttr=18/100.0 # dry matter in cowdung\n",

      "rho=1090 # slurry density in kg/m^3\n",

      "effibrnr=0.6 # burner efficiency\n",

      "Heat=23.0 # heating value of biogas in MJ/m^3\n",

      "\n",

      "dungprd=drymattrprd*2/0.18 # dung produce in kg/day by 2 cows\n",

      "slurry=2*dungprd # slurry produce in kg/day\n",

      "volslurry=slurry/rho # volume of slurry in m^3\n",

      "totalslurry=30*volslurry # for 30 days slurry in m^3\n",

      "digestersize=totalslurry/0.85 # in m^3\n",

      "print \"the volume of digester is \",round(digestersize,2),\"m^3\"\n",

      "\n",

      "gasprd=drymattrprd*2*gasyield # gas produced in m^3/day\n",

      "\n",

      "Energytherm=gasprd*Heat*effibrnr # total thermal energy available in MJ/day\n",

      "\n",

      "\n",

      "thermalpower=Energytherm*1000000/(24*60*60) # in watts\n",

      "\n",

      "print \"total thermal power is \",round(thermalpower,3),\"W\"\n",

      "\n",

      "\n",

      "\n",

      "\n",

      "\n"

     ],

     "language": "python",

     "metadata": {},

     "outputs": [

      {

       "output_type": "stream",

       "stream": "stdout",

       "text": [

        "the volume of digester is  1.44 m^3\n",

        "total thermal power is  140.556 W\n"

       ]

      }

     ],

     "prompt_number": 20

    }

   ],

   "metadata": {}

  }

 ]

}