Investigating noxious gas prodn. in waste dump - by tracer gas injection near gas wells

摘要

Process for investigating and consequently improving or optimising disposal of noxious gases or vapours and odorous substances, forming in waste dumps, involves positioning esp. an array of uniformly spaced suction pipes (esp. gas wells) which extend into the dump and which extract the gases for supply by a collection piping system to a destruction or conversion appts. pref. equipped with a heat and/or energy generating device. The novelty is that (a) an inert tracer substance (esp. tracer gas), which is qualitatively and pref. quantitatively detectable even at concns. below 1 ppb., is introduced in the region of at least one gas well in one or more dump regions being investigated; (b) the tracer gas transport or migration rate or rate spectrum from the drum region to the gas well and the ratio of introduced to extracted tracer gas amounts are determined; and (c) by variation of the suction pressure or rate and/or the location and/or immersion depth of the gas wells, optimisation of the individual gas well capacities and pref. stepwise optimisation of the total gas well capacity is carried out. ADVANTAGE - The process allows optimal utilisation of hydrocarbons (esp. methane), formed by anaerobic breakdown of organic matter in the dump, for energy recovery purposes and gives significant redn. in pollution by dump emissions.